diff --git a/.gitignore b/.gitignore
index 16319d5..c4b1db0 100644
--- a/.gitignore
+++ b/.gitignore
@@ -3,4 +3,6 @@ projects/
 shared_assets/
 black-abode-267208-b3fc82ecef45.json
 black-abode-267208-edc57f25cd47.json
-
+.streamlit/
+.venv/
+.vscode/
\ No newline at end of file
diff --git a/app.py b/app.py
index f40251c..24c92c2 100644
--- a/app.py
+++ b/app.py
@@ -3,31 +3,29 @@ import time
 from pathlib import Path
 import json
 
+from ui_fragments import tab0_data_processing,tab1_asset_generation,tab2_online_video_search,tab3_video_composition
+
 # --- 本地模組匯入 ---
-from utils.paths import get_project_paths, SHARED_ASSETS_DIR, PROJECTS_DIR
-from utils.callbacks import callback_set_project, callback_create_project, callback_run_step,callback_assemble_final_video 
-from utils.helpers import get_notion_page_titles, display_global_status_message
-from ui_fragments.audio_manager import audio_management_fragment
-from ui_fragments.video_manager import video_management_fragment
-from ui_fragments.video_search import video_search_fragment
+from utils.paths import get_project_paths, SHARED_ASSETS_DIR, PROJECTS_DIR,get_project_list
+import callbacks
+from utils.helpers import get_notion_page_titles, display_operation_status
+# from ui_fragments.audio_manager import audio_management_fragment
+# from ui_fragments.video_manager import video_management_fragment
+# from ui_fragments.video_search import video_search_fragment
 
 # --- 匯入外部處理腳本 ---
 # 雖然這些腳本主要在 callbacks 中被呼叫，但在此處匯入有助於理解全貌
-from scripts.step1_notion_sync import update_project_from_notion
-from scripts.step2_translate_ipa import run_step2_translate_ipa
-from scripts.step3_generate_audio import run_step3_generate_audio
-from scripts.step4_concatenate_audio import run_step4_concatenate_audio
-from scripts.step5_generate_ass import run_step5_generate_ass
-from scripts.step6_assemble_video import run_step6_assemble_video
+# from scripts.step1_notion_sync import update_project_from_notion
+# from scripts.step2_translate_ipa import run_step2_translate_ipa
+# from scripts.step3_generate_audio import run_step3_generate_audio
+# from scripts.step4_concatenate_audio import run_step4_concatenate_audio
+# from scripts.step5_generate_ass import run_step5_generate_ass
+# from scripts.step6_assemble_video import run_step6_assemble_video
 
 # --- Streamlit UI 設定 ---
 st.set_page_config(layout="wide", page_title="英語影片自動化工作流程")
 
 # --- 狀態初始化 ---
-if 'current_project' not in st.session_state:
-    st.session_state.current_project = None
-if 'final_video_path' not in st.session_state:
-    st.session_state.final_video_path = None
 if 'show_video' not in st.session_state:
     st.session_state.show_video = False
 if 'operation_status' not in st.session_state:
@@ -41,9 +39,14 @@ if 'selected_videos' not in st.session_state:
 if 'active_preview_id' not in st.session_state:
     st.session_state.active_preview_id = None
 
+if 'project' not in st.session_state:
+    st.session_state.project = None # 'project' 現在儲存的是 Project 物件或 None
+if 'project_selector' not in st.session_state:
+    st.session_state.project_selector = None # 'project_selector' 用來追蹤 selectbox 的狀態
+
 # --- UI 介面 ---
 st.title("🎬 英語影片自動化工作流程")
-display_global_status_message()
+display_operation_status()
 # --- 側邊欄 ---
 with st.sidebar:
     st.header("API & Project Control")
@@ -56,161 +59,126 @@ with st.sidebar:
     st.header("1. 建立新專案")
     try:
         if notion_api_key and notion_database_id:
-            with st.spinner("載入 Notion 頁面..."):
-                page_titles_map = get_notion_page_titles(notion_api_key, notion_database_id)
-                st.session_state.page_titles_map = page_titles_map
-            st.selectbox("選擇一個 Notion 頁面來建立專案:", options=[""] + list(page_titles_map.keys()), index=0, key="selected_title", placeholder="選擇一個頁面...")
+            page_titles_map = get_notion_page_titles(notion_api_key, notion_database_id)
+            st.session_state.page_titles_map = page_titles_map
+            st.selectbox("選擇 Notion 頁面以建立新專案:", 
+                        options=[""] + list(page_titles_map.keys()), 
+                        key="selected_title")
+
             if st.session_state.selected_title:
-                st.button(f"從 '{st.session_state.selected_title}' 建立專案", on_click=callback_create_project)
+                st.button(f"從 '{st.session_state.selected_title}' 建立專案", 
+                        on_click=callbacks.callback_create_project) # 綁定到標準回呼
         else:
             st.warning("請在 Streamlit secrets 中設定 Notion API 金鑰和資料庫 ID。")
     except Exception as e:
         st.error(f"無法載入 Notion 頁面: {e}")
-    
+
     st.divider()
 
     st.header("2. 選擇現有專案")
-    existing_projects = [p.name for p in PROJECTS_DIR.iterdir() if p.is_dir()]
-    selected_project_idx = existing_projects.index(st.session_state.current_project) + 1 if st.session_state.current_project in existing_projects else 0
+
+    # 1. 介面邏輯變得極簡：直接呼叫工具函式
+    existing_projects = get_project_list() 
+
+    # 2. UI 只負責綁定 key 和 on_change 事件
     st.selectbox(
         "或選擇一個現有專案:",
         options=[""] + existing_projects,
-        index=selected_project_idx,
-        key="project_selector",
-        on_change=callback_set_project,
+        key="project_selector", # selectbox 的狀態由 st.session_state.project_selector 控制
+        on_change=callbacks.callback_set_project, # 綁定到標準回呼
         help="選擇您已經建立的專案。"
     )
+# --- 主畫面 ---# 1. 從 session_state 中獲取 Project 物件。這是與專案互動的唯一入口。
+project = st.session_state.get('project')
 
-# --- 主畫面 ---
-if not st.session_state.current_project:
+# 2. 判斷的依據變成了 project 物件是否存在，而不是一個字串。
+if not project:
+    # 如果沒有專案，提示使用者。這部分的邏輯是完美的。
     st.info("👈 請在側邊欄建立新專案或選擇一個現有專案以開始。")
 else:
-    paths = get_project_paths(st.session_state.current_project)
-    project_path = paths["root"] 
+    st.header(f"目前專案：`{project.name}`")
 
-    st.header(f"目前專案：`{st.session_state.current_project}`")
+    tab_names = ["1. 資料處理 & AI 加註", "2. 素材生成", " 線上素材搜尋", "3. 影片合成"]
+    active_tab = st.radio("選擇工作流程步驟:", 
+                          options=tab_names, 
+                          key="main_tabs_radio", 
+                          horizontal=True, 
+                          label_visibility="collapsed")
+    st.markdown("---") 
 
-    tab_names = ["1. 資料處理 & AI 加註", "2. 素材生成", "2.5. 線上素材搜尋", "3. 影片合成"]
-    active_tab = st.radio("選擇工作流程步驟:", options=tab_names, key="main_tabs_radio", horizontal=True, label_visibility="collapsed")
-    st.markdown("---")
-
-    # --- 分頁內容 ---
+#     # --- 分頁內容 ---
     if active_tab == tab_names[0]:
-        data_file = paths["data"]
-        if data_file.exists():
-            with st.container():
-                col1, col2 = st.columns([3, 1])
-                with col1:
-                    st.subheader("專案資料")
-                with col2:
-                    st.button("🔄 從 Notion 同步更新", on_click=callback_run_step, args=(update_project_from_notion,), kwargs={"source": "sync_notion", "spinner_text": "正在同步...", "api_key": notion_api_key, "project_path": project_path}, help="從 Notion 抓取此專案的最新資料並覆寫本地檔案。")
-                with st.expander("預覽專案資料 (data.json)", expanded=False):
-                    st.json(json.loads(data_file.read_text(encoding="utf-8")))
-            st.divider()
-            st.subheader("AI 自動加註")
-            st.button("2. 添加翻譯與 IPA 音標", on_click=callback_run_step, args=(run_step2_translate_ipa,), kwargs={"source": "run_translate", "spinner_text": "正在調用 AI...", "project_path": project_path, "google_creds_path": google_creds_for_translate_path, "notion_api_key": notion_api_key, "notion_database_id": notion_database_id}, disabled=not google_creds_for_translate_path)
-            if not google_creds_for_translate_path:
-                st.warning("請在 secrets.toml 中提供 Google Cloud 翻譯認證檔案的路徑。")
-        else:
-            st.warning("找不到 data.json 檔案。請先從 Notion 同步。")
-        st.divider()
-        st.info("✍️ **人工檢查點**：\n\n1. 請檢查 `Notion` 中的內容是否準確。\n2. 修改完成後，**請務必點擊上方的「從 Notion 同步更新」按鈕**。")
-
-    elif active_tab == tab_names[1]:
         with st.container(border=True):
-            st.subheader("步驟 3.1: 生成單句音訊")
-            st.button("執行生成", on_click=callback_run_step, args=(run_step3_generate_audio,), kwargs={"source": "gen_audio", "spinner_text": "正在生成音訊...", "project_path": project_path, "google_creds_path": google_creds_for_TTS_path}, help="根據 data.json 中的每一句英文，生成對應的 .wav 音訊檔並存放在 audio 資料夾。")
-            
-            st.divider()
+             tab0_data_processing.render_tab(project) 
 
-            st.markdown("##### 步驟 3.2: 組合完整音訊")
-            audio_folder, single_audio_exists = paths["audio"], False
-            if audio_folder.exists() and any(audio_folder.iterdir()):
-                single_audio_exists = True
-            
-            if not single_audio_exists:
-                st.info("請先執行步驟 3.1 以生成單句音訊。")
-            st.button("執行組合", on_click=callback_run_step, args=(run_step4_concatenate_audio,), kwargs={"source": "concat_audio", "spinner_text": "正在組合音訊...", "project_path": project_path}, help="將 audio 資料夾中所有的 .wav 檔，按順序組合成一個名為 combined_audio.wav 的檔案。", disabled=not single_audio_exists)
-            
-            combined_audio_path = paths["combined_audio"]
-            if combined_audio_path.exists():
-                st.success("🎉 完整音訊已組合成功！")
-                st.audio(str(combined_audio_path))
-
-        st.divider()
-
-        with st.container(border=True):
-            st.subheader("步驟 4: 生成 ASS 字幕檔")
-            if not single_audio_exists:
-                st.info("請先執行步驟 3.1 以生成字幕所需的時間戳。")
-            st.button("📝 生成 .ass 字幕檔", on_click=callback_run_step, args=(run_step5_generate_ass,), kwargs={"source": "gen_ass", "spinner_text": "正在生成字幕檔...", "project_path": project_path}, disabled=not single_audio_exists)
-
-        st.divider()
-        audio_management_fragment(paths)
-
-    elif active_tab == tab_names[2]:
-        video_search_fragment(paths)
+    if active_tab == tab_names[1]:
+        tab1_asset_generation.render_tab(project, callbacks)
     
-    elif active_tab == tab_names[3]:
-        video_management_fragment(paths)
+
+    if active_tab == tab_names[2]:
+        tab2_online_video_search.render_tab(project,callbacks)
+    
+    if active_tab == tab_names[3]:
+        tab3_video_composition.render_tab(project, callbacks)
+
         st.divider()
         
-        st.subheader("步驟 6.1: 管理與選擇共享影片素材")
-        shared_videos = [""] + [f.name for f in sorted(SHARED_ASSETS_DIR.glob('*.mp4'))] + [f.name for f in sorted(SHARED_ASSETS_DIR.glob('*.mov'))]
-        with st.container(border=True):
-            st.markdown("##### 從共享素材庫中選擇影片")
-            c1, c2 = st.columns(2)
-            with c1:
-                logo_selection = st.selectbox("選擇 Logo 影片:", shared_videos, key="logo_select")
-                open_selection = st.selectbox("選擇開場影片:", shared_videos, key="open_select")
-            with c2:
-                end_selection = st.selectbox("選擇結尾影片:", shared_videos, key="end_select")
+#         st.subheader("步驟 6.1: 管理與選擇共享影片素材")
+#         shared_videos = [""] + [f.name for f in sorted(SHARED_ASSETS_DIR.glob('*.mp4'))] + [f.name for f in sorted(SHARED_ASSETS_DIR.glob('*.mov'))]
+#         with st.container(border=True):
+#             st.markdown("##### 從共享素材庫中選擇影片")
+#             c1, c2 = st.columns(2)
+#             with c1:
+#                 logo_selection = st.selectbox("選擇 Logo 影片:", shared_videos, key="logo_select")
+#                 open_selection = st.selectbox("選擇開場影片:", shared_videos, key="open_select")
+#             with c2:
+#                 end_selection = st.selectbox("選擇結尾影片:", shared_videos, key="end_select")
             
-            with st.expander("**上傳新的共享素材**"):
-                st.markdown("上傳的影片將存入 `shared_assets` 公共資料夾，可供所有專案重複使用。")
-                uploaded_files = st.file_uploader("上傳新的影片到共享素材庫", type=["mp4", "mov"], accept_multiple_files=True, label_visibility="collapsed")
-                if uploaded_files:
-                    for uploaded_file in uploaded_files:
-                        with open(SHARED_ASSETS_DIR / uploaded_file.name, "wb") as f:
-                            f.write(uploaded_file.getbuffer())
-                    st.success(f"成功上傳 {len(uploaded_files)} 個檔案到共享素材庫！")
-                    time.sleep(1)
-                    st.rerun()
+#             with st.expander("**上傳新的共享素材**"):
+#                 st.markdown("上傳的影片將存入 `shared_assets` 公共資料夾，可供所有專案重複使用。")
+#                 uploaded_files = st.file_uploader("上傳新的影片到共享素材庫", type=["mp4", "mov"], accept_multiple_files=True, label_visibility="collapsed")
+#                 if uploaded_files:
+#                     for uploaded_file in uploaded_files:
+#                         with open(SHARED_ASSETS_DIR / uploaded_file.name, "wb") as f:
+#                             f.write(uploaded_file.getbuffer())
+#                     st.success(f"成功上傳 {len(uploaded_files)} 個檔案到共享素材庫！")
+#                     time.sleep(1)
+#                     st.rerun()
 
-        st.divider()
-        st.subheader("步驟 6.2: 執行最終影片合成")
-        all_videos_selected = all([logo_selection, open_selection, end_selection])
-        if not all_videos_selected:
-            st.info("請從上方的下拉選單中選擇所有四個影片以啟用合成按鈕。")
+#         st.divider()
+#         st.subheader("步驟 6.2: 執行最終影片合成")
+#         all_videos_selected = all([logo_selection, open_selection, end_selection])
+#         if not all_videos_selected:
+#             st.info("請從上方的下拉選單中選擇所有四個影片以啟用合成按鈕。")
         
-        st.button(
-            "🎬 合成最終影片", 
-            on_click=callback_assemble_final_video, 
-            kwargs={
-                "paths": paths,
-                "source": "assemble_video", 
-                "spinner_text": "影片合成中，請稍候...", 
-                "project_path": paths['root'], # 傳遞給 run_step6_assemble_video
-                "logo_video": SHARED_ASSETS_DIR / logo_selection if logo_selection else None, 
-                "open_video": SHARED_ASSETS_DIR / open_selection if open_selection else None, 
-                "end_video": SHARED_ASSETS_DIR / end_selection if end_selection else None
-            }, 
-            disabled=not all_videos_selected
-        )
+#         st.button(
+#             "🎬 合成最終影片", 
+#             on_click=callback_assemble_final_video, 
+#             kwargs={
+#                 "paths": paths,
+#                 "source": "assemble_video", 
+#                 "spinner_text": "影片合成中，請稍候...", 
+#                 "project_path": paths['root'], # 傳遞給 run_step6_assemble_video
+#                 "logo_video": SHARED_ASSETS_DIR / logo_selection if logo_selection else None, 
+#                 "open_video": SHARED_ASSETS_DIR / open_selection if open_selection else None, 
+#                 "end_video": SHARED_ASSETS_DIR / end_selection if end_selection else None
+#             }, 
+#             disabled=not all_videos_selected
+#         )
 
 
-        if st.session_state.final_video_path and Path(st.session_state.final_video_path).exists():
-            st.divider()
-            st.header("🎉 影片製作完成！")
-            st.checkbox("顯示/隱藏影片", key="show_video", value=True)
-            if st.session_state.show_video:
-                st.video(st.session_state.final_video_path)
+#         if st.session_state.final_video_path and Path(st.session_state.final_video_path).exists():
+#             st.divider()
+#             st.header("🎉 影片製作完成！")
+#             st.checkbox("顯示/隱藏影片", key="show_video", value=True)
+#             if st.session_state.show_video:
+#                 st.video(st.session_state.final_video_path)
 
-            with open(st.session_state.final_video_path, "rb") as file:
-                st.download_button(
-                    "📥 下載專案影片", 
-                    data=file, 
-                    file_name=Path(st.session_state.final_video_path).name,
-                    mime="video/mp4",
-                    use_container_width=True
-                )
+#             with open(st.session_state.final_video_path, "rb") as file:
+#                 st.download_button(
+#                     "📥 下載專案影片", 
+#                     data=file, 
+#                     file_name=Path(st.session_state.final_video_path).name,
+#                     mime="video/mp4",
+#                     use_container_width=True
+#                 )
diff --git a/callbacks.py b/callbacks.py
new file mode 100644
index 0000000..9c93617
--- /dev/null
+++ b/callbacks.py
@@ -0,0 +1,329 @@
+import streamlit as st
+from pathlib import Path
+from scripts.step1_notion_sync import create_project_from_page
+from scripts.step6_assemble_video import run_step6_assemble_video
+from utils.paths import PROJECTS_DIR ,get_project_list
+from utils import asset_manager
+import requests
+from project_model import Project 
+from config import SHARED_ASSETS_DIR 
+
+# --- 專案與流程控制 Callbacks ---
+def callback_set_project():
+    """當使用者從下拉選單選擇一個現有專案時，設定當前的 Project 物件。"""
+    selected_name = st.session_state.get("project_selector")
+    if selected_name:
+        with st.spinner(f"正在載入專案 '{selected_name}'..."):
+            st.session_state.project = Project(project_name=selected_name)
+            # 【新】回報操作狀態
+            st.session_state.operation_status = {
+                "type": "success", 
+                "message": f"專案 '{selected_name}' 已成功載入。"
+            }
+    else:
+        st.session_state.project = None
+
+def callback_create_project():
+    """從 Notion 頁面建立一個新專案的回呼函式。"""
+    project_name = st.session_state.get("selected_title")
+    if not project_name:
+        # 【改動】不再呼叫 st.warning，而是設定狀態
+        st.session_state.operation_status = {"type": "warning", "message": "請先選擇一個 Notion 頁面。"}
+        return
+
+    if project_name in get_project_list():
+        # 【改動】不再呼叫 st.error，而是設定狀態
+        st.session_state.operation_status = {
+            "type": "error", 
+            "message": f"專案 '{project_name}' 已存在。請從下方的選單選擇它。"
+        }
+        st.session_state.project_selector = project_name
+        callback_set_project()
+        st.rerun() # 此處的 rerun 用於強制更新 selectbox，是可接受的進階用法
+        return
+    
+    page_titles_map = st.session_state.get("page_titles_map", {})
+    page_id_to_create = page_titles_map.get(project_name)
+
+    if not page_id_to_create:
+        st.session_state.operation_status = {
+            "type": "error", 
+            "message": f"內部錯誤：找不到 '{project_name}' 的 Notion 頁面 ID。"
+        }
+        return
+        
+    try:
+        new_project = Project.create_new(project_name=project_name, notion_page_id=page_id_to_create)
+        st.session_state.project = new_project
+        st.session_state.project_selector = new_project.name
+        # 【改動】不再呼叫 st.success，而是設定狀態
+        st.session_state.operation_status = {
+            "type": "success", 
+            "message": f"專案 '{project_name}' 的框架已成功建立！"
+        }
+        st.session_state.selected_title = ""
+        
+    except Exception as e:
+        st.session_state.operation_status = {"type": "error", "message": f"建立專案時發生錯誤: {e}"}
+
+def _execute_project_method(method_name: str, spinner_text: str):
+    """(新) 輔助函式，用於執行 Project 方法並處理回傳的狀態。"""
+    project = st.session_state.get('project')
+    if not project:
+        st.session_state.operation_status = {"type": "warning", "message": "請先選擇一個專案。"}
+        return
+
+    method_to_call = getattr(project, method_name, None)
+    if not method_to_call:
+        st.session_state.operation_status = {"type": "error", "message": f"內部錯誤：找不到方法 {method_name}。"}
+        return
+    
+    with st.spinner(spinner_text):
+        success= method_to_call()
+        st.session_state.operation_status = {"type": "success" if success else "error"}
+
+# --- 所有後續的 Callback 現在都變得極其簡潔 ---
+
+def callback_sync_notion():
+    """回呼：執行 Notion 同步。"""
+    _execute_project_method("sync_from_notion", "正在從 Notion 同步...")
+
+def callback_add_zh_ipa():
+    """回呼：執行 AI 加註（翻譯與 IPA）。"""
+    _execute_project_method("add_translation_and_ipa", "正在呼叫 AI 進行翻譯與音標加註...")
+
+def callback_generate_sentence_audio():
+    """回呼：生成音訊片段。"""
+    _execute_project_method("generate_sentence_audio", "正在生成音訊片段...")
+
+def callback_concatenate_audio():
+    """回呼：組合完整音訊。"""
+    _execute_project_method("concatenate_audio", "正在組合完整音訊...")
+
+def callback_generate_subtitles():
+    """回呼：生成 ASS 字幕檔。"""
+    _execute_project_method("generate_ass_subtitles", "正在生成 ASS 字幕檔...")
+
+
+def assemble_final_video(logo_video_name, open_video_name, end_video_name):
+    """
+    【新】回呼：執行最終影片的合成。
+    只接收檔名，內部處理路徑和業務邏輯。
+    """
+    try:
+        project = st.session_state.get('project')
+        if not project:
+            # 如果找不到專案，立即更新狀態並終止函式，避免錯誤
+            st.session_state.operation_status = {
+                "type": "error", 
+                "message": "操作失敗：找不到有效的專案。請重新選擇或建立一個專案。"
+            }
+            return # 提前退出函式
+        # 1. 在回呼函式內部，根據檔名組合出完整的路徑
+        logo_path = SHARED_ASSETS_DIR / logo_video_name if logo_video_name else None
+        open_path = SHARED_ASSETS_DIR / open_video_name if open_video_name else None
+        end_path = SHARED_ASSETS_DIR / end_video_name if end_video_name else None
+
+        # 2. 將核心業務邏輯委派給 Project 物件
+        #    我們將在這裡呼叫一個新的 project.assemble_video 方法
+        with st.spinner("影片合成中，這可能需要幾分鐘，請耐心等候..."):
+            project.assemble_video(
+                logo_video=logo_path,
+                open_video=open_path,
+                end_video=end_path
+            )
+
+    except Exception as e:
+        # 無論是上面的 ValueError，還是 project.assemble_video 中未被捕捉的錯誤
+        error_message = f"執行影片合成時發生錯誤: {e}"
+        
+        
+        # 將統一格式的錯誤訊息回報給 UI，讓使用者知道發生了什麼
+        st.session_state.operation_status = {
+            "type": "error", 
+            "message": error_message
+        }
+
+def callback_run_step(step_function, source="unknown", **kwargs):
+    spinner_text = kwargs.pop("spinner_text", "正在處理中，請稍候...")
+    with st.spinner(spinner_text):
+        result = step_function(**kwargs)
+        if len(result) == 2: success, msg = result
+        elif len(result) == 3: success, msg, _ = result
+        else: success, msg = False, "步驟函式回傳格式不符！"
+        st.session_state.operation_status = {"success": success, "message": msg, "source": source}
+        if step_function == run_step6_assemble_video and success:
+            st.session_state.final_video_path = str(result[2])
+            st.session_state.show_video = True
+
+def toggle_all_video_checkboxes(self, video_files):
+    """【新】切換所有影片核取方塊的選取狀態。"""
+    select_all_state = st.session_state.get('select_all_videos', False)
+    for video_file in video_files:
+        st.session_state[f"delete_cb_{video_file.name}"] = select_all_state
+
+def delete_selected_videos(self):
+    """【新】刪除在 UI 中選取的影片。"""
+    if not self.project:
+        st.session_state.operation_status = {"type": "warning", "message": "請先選擇一個專案。"}
+        return
+
+    output_dir = self.project.paths["output"]
+    deleted_files_count = 0
+    errors = []
+    files_to_delete = [
+        key.replace("delete_cb_", "", 1) 
+        for key, value in st.session_state.items() 
+        if key.startswith("delete_cb_") and value
+    ]
+
+    if not files_to_delete:
+        st.session_state.operation_status = {"type": "info", "message": "沒有選擇任何要刪除的影片。"}
+        return
+
+    for filename in files_to_delete:
+        try:
+            file_path = output_dir / filename
+            if file_path.exists():
+                if st.session_state.get("final_video_path") and Path(st.session_state.final_video_path) == file_path:
+                    st.session_state.final_video_path = None
+                file_path.unlink()
+                deleted_files_count += 1
+                del st.session_state[f"delete_cb_{filename}"]
+        except Exception as e:
+            errors.append(f"刪除 {filename} 時出錯: {e}")
+
+    if errors:
+        message = f"刪除操作有誤。成功刪除 {deleted_files_count} 個檔案，但發生以下錯誤: " + ", ".join(errors)
+        st.session_state.operation_status = {"type": "error", "message": message}
+    else:
+        message = f"成功刪除 {deleted_files_count} 個影片。"
+        st.session_state.operation_status = {"type": "success", "message": message}
+
+def upload_shared_videos():
+    """
+    回呼：處理共享影片的上傳請求。
+    """
+    uploaded_files = st.session_state.get("shared_video_uploader", [])
+    
+    # 委派任務給 asset_manager
+    saved_count, errors = asset_manager.save_uploaded_shared_videos(uploaded_files)
+
+    # 根據結果更新 UI 狀態
+    if errors:
+        message = f"處理完成。成功 {saved_count} 個，失敗 {len(errors)} 個。錯誤: {', '.join(errors)}"
+        st.session_state.operation_status = {"type": "error", "message": message}
+    elif saved_count > 0:
+        message = f"成功上傳 {saved_count} 個新素材到共享庫！"
+        st.session_state.operation_status = {"type": "success", "message": message}
+    
+    st.session_state.shared_video_uploader = []
+
+def callback_download_videos(paths: dict):
+    with st.spinner("正在下載影片，請稍候..."):
+        videos_to_download = {vid: info for vid, info in st.session_state.selected_videos.items() if info['selected']}
+        if not videos_to_download:
+            st.session_state.operation_status = {"success": False, "message": "尚未選擇任何影片。", "source": "download_videos"}
+            return
+
+        download_dir = paths["output"] / "test"
+        download_dir.mkdir(parents=True, exist_ok=True)
+        
+        # --- 循序命名邏輯 START ---
+        existing_files = list(download_dir.glob('*.mp4')) + list(download_dir.glob('*.mov'))
+        existing_numbers = []
+        for f in existing_files:
+            try:
+                # 從檔名 (不含副檔名) 中提取數字
+                existing_numbers.append(int(f.stem))
+            except ValueError:
+                # 忽略那些不是純數字的檔名
+                continue
+        
+        # 決定起始編號
+        start_counter = max(existing_numbers) + 1 if existing_numbers else 1
+        counter = start_counter
+        # --- 循序命名邏輯 END ---
+
+        total, download_count, errors = len(videos_to_download), 0, []
+        
+        for i, (video_id, info) in enumerate(videos_to_download.items()):
+            url = info['url']
+            original_path = Path(url)
+            
+            # 使用循序命名
+            new_video_name = f"{counter}{original_path.suffix}"
+            save_path = download_dir / new_video_name
+            
+            try:
+                if not save_path.exists():
+                    response = requests.get(url, stream=True)
+                    response.raise_for_status()
+                    with open(save_path, 'wb') as f:
+                        f.write(response.content)
+                    download_count += 1
+                    counter += 1 # 只有在成功下載後才增加計數器
+            except Exception as e:
+                errors.append(f"下載影片 {original_path.name} 失敗: {e}")
+        
+        if errors:
+            final_message = f"任務完成，但有 {len(errors)} 個錯誤。成功處理 {download_count}/{total} 個影片。\n" + "\n".join(errors)
+            st.session_state.operation_status = {"success": False, "message": final_message, "source": "download_videos"}
+        else:
+            final_message = f"任務完成！成功下載 {download_count}/{total} 個影片到專案的 `output/test` 資料夾，並已自動循序命名。"
+            st.session_state.operation_status = {"success": True, "message": final_message, "source": "download_videos"}
+
+def callback_toggle_preview(video_id):
+    if st.session_state.active_preview_id == video_id: st.session_state.active_preview_id = None
+    else: st.session_state.active_preview_id = video_id
+
+
+def callback_delete_selected_audios(paths: dict):
+    deleted_files_count = 0
+    errors = []
+    
+    files_to_delete_names = []
+    for key, value in st.session_state.items():
+        if key.startswith("delete_audio_cb_") and value:
+            filename = key.replace("delete_audio_cb_", "", 1)
+            files_to_delete_names.append(filename)
+
+    if not files_to_delete_names:
+        st.session_state.operation_status = {"success": True, "message": "🤔 沒有選擇任何要刪除的音訊。", "source": "delete_audios"}
+        return
+
+    audio_dir = paths["audio"]
+    output_dir = paths["output"]
+
+    for filename in files_to_delete_names:
+        try:
+            file_path_audio = audio_dir / filename
+            file_path_output = output_dir / filename
+            
+            file_path_to_delete = None
+            if file_path_audio.exists():
+                file_path_to_delete = file_path_audio
+            elif file_path_output.exists():
+                file_path_to_delete = file_path_output
+
+            if file_path_to_delete:
+                file_path_to_delete.unlink()
+                deleted_files_count += 1
+                del st.session_state[f"delete_audio_cb_{filename}"]
+            else:
+                errors.append(f"找不到檔案 {filename}。")
+
+        except Exception as e:
+            errors.append(f"刪除 {filename} 時出錯: {e}")
+
+    if errors:
+        message = f"❌ 刪除操作有誤。成功刪除 {deleted_files_count} 個檔案，但發生以下錯誤: " + ", ".join(errors)
+        st.session_state.operation_status = {"success": False, "message": message, "source": "delete_audios"}
+    else:
+        message = f"✅ 成功刪除 {deleted_files_count} 個音訊。"
+        st.session_state.operation_status = {"success": True, "message": message, "source": "delete_audios"}
+
+def toggle_all_audio_checkboxes(audio_files):
+    select_all_state = st.session_state.get('select_all_audios', False)
+    for audio_file in audio_files:
+        st.session_state[f"delete_audio_cb_{audio_file.name}"] = select_all_state
\ No newline at end of file
diff --git a/config.py b/config.py
new file mode 100644
index 0000000..baf78e6
--- /dev/null
+++ b/config.py
@@ -0,0 +1,15 @@
+# config.py
+
+from pathlib import Path
+
+# 專案的根目錄，可以根據您的實際結構調整
+# __file__ 是目前檔案 (config.py) 的路徑
+# .parent 會取得其所在的目錄
+# .parent.parent 會取得上上層目錄
+APP_ROOT = Path(__file__).parent 
+
+# 所有專案的根目錄
+PROJECTS_DIR = APP_ROOT / "projects"
+
+# 共享素材庫的目錄
+SHARED_ASSETS_DIR = APP_ROOT / "shared_assets"
\ No newline at end of file
diff --git a/project_model.py b/project_model.py
new file mode 100644
index 0000000..7a06b17
--- /dev/null
+++ b/project_model.py
@@ -0,0 +1,916 @@
+from utils.paths import PROJECTS_DIR,get_project_paths
+from utils.helpers import get_media_duration,get_media_info
+from pathlib import Path
+from typing import List, Dict, Optional
+import streamlit as st # 為了存取 secrets
+from scripts import step1_notion_sync, step2_translate_ipa
+import json
+from notion_client import Client
+from google.cloud import translate_v2 as translate
+import eng_to_ipa 
+from google.cloud import texttospeech 
+from pydub import AudioSegment 
+from google.api_core.exceptions import GoogleAPICallError
+
+import re # 用於正規表示式匹配檔案名稱
+import pysubs2 # 專業字幕處理函式庫
+import librosa # 專業音訊分析函式庫
+import subprocess 
+import logging
+import math
+import os
+# 設定日誌
+logging.basicConfig(level=logging.INFO, format='%(asctime)s - %(levelname)s - %(message)s')
+class Project:
+    """
+    代表一個獨立的影片專案，封裝其檔案結構和資料。
+    """
+    def __init__(self, project_name: str, page_id: str | None = None):
+        """
+        初始化一個 Project 實例。注意：這不會在磁碟上建立檔案。
+        若要建立新專案，請使用 Project.create_new()。
+
+        Args:
+            project_name (str): 專案的名稱，對應其目錄名稱。
+        """
+        if not project_name or not isinstance(project_name, str):
+            raise ValueError("專案名稱必須是一個非空的字串。")
+        self.name = project_name
+        self.root_path: Path = PROJECTS_DIR / self.name
+        self.paths: dict[str, Path] = get_project_paths(self.name)
+        self.data = self._load_data()
+        if page_id:
+            self.page_id = page_id
+        elif self.data and 'id' in self.data:
+            self.page_id = self.data['id']
+        else:
+            self.page_id = None 
+        
+
+    def _load_data(self) -> dict | None:
+        """嘗試從 data.json 載入資料，若失敗則回傳 None。"""
+        data_path = self.paths.get('data')
+        if data_path and data_path.exists():
+            try:
+                return json.loads(data_path.read_text(encoding="utf-8"))
+            except (json.JSONDecodeError, FileNotFoundError):
+                return None
+        return None
+    
+    def create_directories(self):
+        """
+        確保專案所需的所有目錄都存在。
+        這個方法是「冪等」的，即使目錄已存在，重複呼叫也不會出錯。
+        """
+        print(f"正在為專案 '{self.name}' 檢查並建立目錄結構...")
+        
+        # 根據 get_project_paths 的定義，我們知道 'audio' 和 'output' 是需要建立的目錄
+        # 將需要建立的目錄鍵名放入一個列表中，方便管理
+        required_dirs = ['root','audio', 'output']
+        
+        for dir_key in required_dirs:
+            directory_path = self.paths.get(dir_key)
+            if directory_path:
+                # 使用 exist_ok=True 避免在目錄已存在時拋出錯誤
+                # 使用 parents=True 確保即使未來路徑變為巢狀結構也能成功建立
+                directory_path.mkdir(parents=True, exist_ok=True)
+                print(f"  - 目錄 '{directory_path}' 已確認存在。")
+            else:
+                print(f"  - 警告：在路徑設定中找不到鍵名 '{dir_key}'。")
+            
+    @classmethod
+    def create_new(cls, project_name: str, notion_page_id: str) -> 'Project':
+        """
+        在檔案系統上建立一個新的專案目錄結構。
+
+        Args:
+            project_name (str): 新專案的名稱。
+
+        Returns:
+            Project: 新建立專案的實例。
+
+        Raises:
+            FileExistsError: 如果同名專案已存在。
+        """
+        project = cls(project_name, page_id=notion_page_id)
+        project.create_directories()
+        return project
+
+    def __repr__(self) -> str:
+        return f"<Project(name='{self.name}')>"
+
+    def __str__(self) -> str:
+        return self.name
+
+    def sync_from_notion(self) -> bool:
+        """
+        從 Notion 同步更新專案的 data.json 檔案。
+        這個方法是自給自足的，它知道自己的 page_id 和如何獲取 API Key。
+        """
+        if not self.page_id:
+            st.session_state.operation_status = {
+                "type": "error",
+                "message": "內部錯誤：此專案沒有關聯的 Notion 頁面 ID。"
+            }
+            return False  
+        target_page_id = self.page_id
+
+        api_key = st.secrets.get("NOTION_API_KEY")
+        if not api_key:
+            st.session_state.operation_status = {
+                "type": "error",
+                "message": "錯誤：找不到 Notion API Key。"
+            }
+            return False
+
+        try:
+            client = Client(auth=api_key)
+            print(f"正在從 Notion 更新頁面 ID: {target_page_id}")
+            page_data = client.pages.retrieve(page_id=target_page_id)
+            
+            # 這裡可以重用 step1 中的 extract_property_value 邏輯
+            # 最好是將該函式也移入 Project 類別作為一個私有方法 _extract_property_value
+            properties = page_data['properties']
+            updated_entry = {"id": page_data['id']}
+            for prop_name, prop_data in properties.items():
+                updated_entry[prop_name] = self._extract_property_value(prop_data)
+
+            # 更新 data.json 檔案
+            with open(self.paths['data'], 'w', encoding='utf-8') as f:
+                json.dump(updated_entry, f, ensure_ascii=False, indent=2)
+            
+            # 同時更新記憶體中的資料，保持同步
+            self.data = updated_entry
+            self.data = self._load_data() 
+            st.session_state.operation_status = {
+                "type": "success",
+                "message": f"專案 '{self.name}' 已成功從 Notion 同步更新。"
+            }            
+            return True
+
+        except Exception as e:
+            st.session_state.operation_status = {
+                "type": "error",
+                "message": f"更新專案 '{self.name}' 時發生錯誤: {e}"
+            }
+            return False
+        
+    def _extract_property_value(self,property_data):
+        """從 Notion 頁面屬性中提取純文字值。"""
+        prop_type = property_data.get('type')
+        if prop_type == 'title':
+            return property_data['title'][0]['plain_text'] if property_data.get('title') else ""
+        elif prop_type == 'rich_text':
+            return "\n".join([text['plain_text'] for text in property_data.get('rich_text', [])])
+        elif prop_type == 'select' and property_data.get('select'):
+            return property_data['select']['name']
+        elif prop_type == 'date' and property_data.get('date'):
+            return property_data['date']['start']
+        return None
+      
+    @classmethod
+    def create_from_notion(cls, page_id: str, page_title: str):
+        """
+        工廠方法：從一個 Notion 頁面完整建立一個新專案。
+        """
+        api_key = st.secrets.get("NOTION_API_KEY")
+        if not api_key:
+            raise ValueError("無法建立專案，缺少 Notion API Key。")
+
+        # 1. 先使用既有的 create_new 建立專案實體和目錄結構
+        project = cls.create_new(project_name=page_title)
+
+        # 2. 執行從 Notion 抓取資料並寫入 data.json 的邏輯
+        try:
+            client = Client(auth=api_key)
+            page_data = client.pages.retrieve(page_id=page_id)
+            properties = page_data['properties']
+            
+            # 使用 _extract_property_value 來解析資料
+            page_entry = {"id": page_data['id']}
+            for prop_name, prop_data in properties.items():
+                page_entry[prop_name] = project._extract_property_value(prop_data)
+
+            # 將資料寫入檔案並更新物件狀態
+            with open(project.paths['data'], 'w', encoding='utf-8') as f:
+                json.dump(page_entry, f, ensure_ascii=False, indent=2)
+            project.data = page_entry
+            
+            return project # 回傳完整初始化的專案物件
+
+        except Exception as e:
+            # 如果出錯，可能需要考慮刪除已建立的空資料夾，以保持系統乾淨
+            # (這部分屬於錯誤處理的細化)
+            raise IOError(f"從 Notion 頁面 (ID: {page_id}) 抓取資料時失敗: {e}")
+        
+ 
+    _translate_client = None
+
+    @property
+    def translate_client(self):
+        """
+        延遲初始化 (Lazy Initialization) Google Translate 客戶端。
+        只有在第一次真正需要翻譯時，才會建立客戶端實例，
+        並將其儲存起來以供後續重複使用，避免重複認證。
+        """
+        if self._translate_client is None:
+            creds_path = st.secrets.get("GOOGLE_CREDS_TRANSLATE_PATH")
+            if not creds_path:
+                raise ValueError("未在 secrets 中設定 Google Cloud 翻譯認證檔案路徑。")
+            
+            print("正在初始化 Google Translate 客戶端...")
+            self._translate_client = translate.Client.from_service_account_json(creds_path)
+            
+        return self._translate_client
+
+    def add_translation_and_ipa(self) -> bool:
+        """
+        為專案資料添加翻譯和 IPA 音標。
+        這是協調器，負責整個流程的控制。
+        """
+        # 1. 檢查前置條件：確保核心資料已存在
+        if not self.data or "en" not in self.data:
+            st.session_state.operation_status = {
+                "type": "error",
+                "message": "錯誤：專案資料不完整或缺少英文原文 ('en')。"
+            }
+            return False
+
+        # 2. 準備處理資料
+        # 從 `data.json` 讀取英文句子列表[1]
+        english_sentences = self.data["en"].strip().split('\n')
+        
+        translated_sentences = []
+        ipa_sentences = []
+        
+        # 3. 遍歷每一句，呼叫輔助方法進行處理
+        for sentence in english_sentences:
+            if not sentence:
+                continue
+            
+            # 呼叫封裝好的翻譯方法
+            translated = self._call_google_translate(sentence)
+            translated_sentences.append(translated if translated is not None else "[翻譯失敗]")
+            
+            # 呼叫封裝好的 IPA 轉換方法
+            ipa = self._get_ipa_for_text(sentence)
+            ipa_sentences.append(ipa if ipa is not None else "[轉換失敗]")
+
+        # 4. 將處理結果更新回 self.data
+        self.data['zh'] = "\n".join(translated_sentences)
+        self.data['ipa'] = "\n".join(ipa_sentences)
+
+        try:
+            # 首先，將更新後的資料寫回本地 data.json
+            with open(self.paths['data'], 'w', encoding='utf-8') as f:
+                json.dump(self.data, f, ensure_ascii=False, indent=2)
+            
+            # 然後，呼叫新方法將結果同步回 Notion
+            if self._update_single_notion_page():
+                st.session_state.operation_status = {
+                    "type": "success",
+                    "message": "AI 加註完成，並已成功寫回 Notion！🚀"
+                }
+                return True
+            else:
+                st.session_state.operation_status = {
+                    "type": "warning",
+                    "message": "AI 加註已完成，但寫回 Notion 時失敗。請稍後手動同步。"
+                }
+                return False
+            
+        except IOError as e:
+            st.session_state.operation_status = {
+                "type": "error",
+                "message": f"寫入本地 data.json 時發生錯誤: {e}"
+            }
+            return False        
+
+    def _update_single_notion_page(self) -> bool:
+        """
+        (私有方法) 將 self.data 中的 'zh' 和 'ipa' 欄位更新回對應的 Notion 頁面。
+        """
+        if not self.page_id:
+            st.session_state.operation_status = {
+                "type": "error",
+                "message": "無法更新 Notion：專案缺少 page_id。"
+            }
+            return False
+
+        api_key = st.secrets.get("NOTION_API_KEY")
+        if not api_key:
+            st.session_state.operation_status = {
+                "type": "error",
+                "message": "無法更新 Notion：缺少 API Key。"
+            }
+            return False
+
+        try:
+            client = Client(auth=api_key)
+            
+            # 準備要更新的屬性
+            # 注意：這裡的 "中文翻譯" 和 "IPA音標" 必須與您 Notion Database 中的欄位名稱完全一致！
+
+            properties_to_update = {
+                # 假設您在 Notion 中的欄位名稱就是 "zh"
+                # 如果不是，請修改 "zh" 為您實際的欄位名稱，例如 "中文翻譯"
+                "zh": {
+                    "rich_text": [
+                        {
+                            "type": "text",
+                            "text": {
+                                "content": self.data.get('zh', '')
+                            }
+                        }
+                    ]
+                },
+                # 假設您在 Notion 中的欄位名稱就是 "ipa"
+                # 如果不是，請修改 "ipa" 為您實際的欄位名稱，例如 "IPA"
+                "ipa": {
+                    "rich_text": [
+                        {
+                            "type": "text",
+                            "text": {
+                                "content": self.data.get('ipa', '')
+                            }
+                        }
+                    ]
+                }
+            }            
+            print(f"正在將 AI 加註結果寫回 Notion 頁面: {self.page_id}")
+            client.pages.update(page_id=self.page_id, properties=properties_to_update)
+            return True
+
+        except Exception as e:
+            st.session_state.operation_status = {
+                "type": "error",
+                "message": f"更新 Notion 頁面時發生 API 錯誤: {e}"
+            }
+            return False
+        
+    def _call_google_translate(self, text: str) -> str | None:
+        """
+        (輔助) 呼叫 Google Translate API。
+        成功時返回翻譯字串，失敗時在後台記錄錯誤並返回 None。
+        """
+        try:
+            result = self.translate_client.translate(text, target_language="zh-TW")
+            return result.get('translatedText')
+        except GoogleAPICallError as e:
+            # 不直接顯示 UI 警告，改為在後台記錄，讓呼叫者決定如何處理
+            print(f"警告：Google API 呼叫失敗 - {e.message}")
+            return None
+        except Exception as e:
+            # 同上，記錄詳細錯誤
+            print(f"錯誤：翻譯 '{text[:20]}...' 時發生未預期的錯誤: {e}")
+            return None
+
+
+    def _get_ipa_for_text(self, text: str) -> str | None:
+        """
+        為給定的英文文字獲取 IPA 音標。
+        失敗時在後台記錄錯誤並返回 None。
+        """
+        if not text:
+            return ""
+
+        try:
+            # ... (您原有的 IPA 轉換邏輯保持不變) ...
+            ipa_word_list = eng_to_ipa.convert(text, keep_punct=True)
+            if not isinstance(ipa_word_list, list):
+                return str(ipa_word_list)
+            
+            final_ipa_string = ' '.join(ipa_word_list)
+            final_ipa_string = final_ipa_string.replace('*', '')
+            final_ipa_string = final_ipa_string.replace(' ,', ',').replace(' .', '.').replace(' ?', '?').replace(' !', '!')
+            
+            return final_ipa_string
+
+        except Exception as e:
+            print(f"警告：無法為 '{text[:20]}...' 獲取 IPA 音標: {e}")
+            return None
+        
+
+
+    _tts_client = None # 為 TTS Client 新增一個儲存屬性
+
+    @property
+    def tts_client(self):
+        """延遲初始化 Google Text-to-Speech 客戶端，高效且僅在需要時執行一次。"""
+        if self._tts_client is None:
+            creds_path = st.secrets.get("GOOGLE_CREDS_TTS_PATH")
+            if not creds_path:
+                raise ValueError("未在 secrets 中設定 Google Cloud TTS 認證檔案路徑。")
+            self._tts_client = texttospeech.TextToSpeechClient.from_service_account_json(creds_path)
+        return self._tts_client
+    
+    def generate_sentence_audio(self) -> bool:
+        """
+        為專案中每一對中英文句子，生成一個包含多種聲音的「教學音訊片段」。
+        """
+        # 1. 檢查前置條件
+        if not self.data or "en" not in self.data or "zh" not in self.data:
+            st.session_state.operation_status = {
+                "type": "error",
+                "message": "錯誤：專案資料不完整，必須同時包含 'en' 和 'zh' 欄位。"
+            }
+            return False
+
+        # 2. 讀取並配對中英文句子
+        english_sentences = [line for line in self.data["en"].strip().split('\n') if line]
+        chinese_sentences = [line for line in self.data["zh"].strip().split('\n') if line]
+
+        if len(english_sentences) != len(chinese_sentences):
+            st.session_state.operation_status = {
+                "type": "error",
+                "message": "en zh數量不符合。"
+            }
+            return False        
+        # 3. 從 data.json 讀取 voice 設定，如果沒有則使用預設值
+        voice_config = {
+            'english_voice_1': self.data.get("english_voice_1", "en-US-Wavenet-I"),
+            'english_voice_2': self.data.get("english_voice_2", "en-US-Wavenet-F"),
+            'chinese_voice': self.data.get("chinese_voice", "cmn-TW-Wavenet-B")
+        }
+        print("使用的語音設定：", voice_config) # 提供除錯資訊
+
+        audio_dir = self.paths['audio']
+        audio_dir.mkdir(parents=True, exist_ok=True)
+
+        success_count = 0
+        total_count = min(len(english_sentences), len(chinese_sentences))
+        if total_count == 0:
+            print("沒有找到任何可處理的句子對。")
+            return False
+            
+        progress_bar = st.progress(0, text="正在生成教學音訊片段...")
+
+        for i in range(total_count):
+            item_en = english_sentences[i]
+            item_zh = chinese_sentences[i]
+            output_path = audio_dir / f"{i:03d}.wav"
+            
+            # 4. 呼叫新的 SSML 生成器
+            ssml_content = self._generate_ssml(item_en, item_zh, voice_config)
+            
+            # 5. 呼叫 TTS API (無需修改)
+            if self._call_google_tts(ssml_content, output_path,default_voice_name=voice_config['english_voice_1']):
+                success_count += 1
+            
+            progress_bar.progress((i + 1) / total_count, text=f"正在生成教學音訊... ({i+1}/{total_count})")
+        
+        progress_bar.empty()
+
+        if success_count > 0:
+            st.session_state.operation_status = {
+                "type": "success",
+                "message": "音訊生成成功！。"
+            }
+            return True
+        else:
+            st.session_state.operation_status = {
+                "type": "error",
+                "message": "音訊生成失敗！。"
+            }
+            return False
+
+
+    def _generate_ssml(self, item_en: str, item_zh: str, voice_config: dict) -> str:
+        """
+        (新輔助方法) 根據模板，生成包含多種聲音的教學 SSML。
+        """
+        # 對文本進行 XML 轉義，防止特殊字元破壞 SSML 結構
+        safe_en = item_en.replace('&', '&amp;').replace('<', '&lt;').replace('>', '&gt;')
+        safe_zh = item_zh.replace('&', '&amp;').replace('<', '&lt;').replace('>', '&gt;')
+
+        return f"""
+<speak>
+    <break time="2s"/>
+    <voice name="{voice_config['english_voice_1']}">
+        <prosody rate="medium" pitch="medium">{safe_en}</prosody>
+    </voice>
+    <break time="2s"/>
+    <voice name="{voice_config['english_voice_2']}">
+        <prosody rate="70%" pitch="medium">{safe_en}</prosody>
+    </voice>
+    <break time="2s"/>
+    <voice name="{voice_config['chinese_voice']}">
+        <prosody rate="medium" pitch="+2st">{safe_zh}</prosody>
+    </voice>
+    <break time="1.5s"/>
+    <voice name="{voice_config['english_voice_2']}">
+        <prosody rate="110%" pitch="medium">{safe_en}</prosody>
+    </voice>
+    <break time="1s"/>
+</speak>
+"""
+
+    def _call_google_tts(self, ssml_content: str, output_path: Path, default_voice_name: str) -> bool:
+        """
+        (輔助方法已更新) 現在只接收 SSML 內容，不再需要 voice_name 參數。
+        """
+        try:
+            synthesis_input = texttospeech.SynthesisInput(ssml=ssml_content)
+            
+            voice_params = texttospeech.VoiceSelectionParams(
+                # 從 'en-US-Wavenet-D' 中提取 'en-US'
+                language_code='-'.join(default_voice_name.split('-')[:2]),
+                name=default_voice_name
+            )
+            audio_config = texttospeech.AudioConfig(
+                audio_encoding=texttospeech.AudioEncoding.LINEAR16,
+                sample_rate_hertz=24000
+            )
+
+            response = self.tts_client.synthesize_speech(
+                input=synthesis_input, 
+                voice=voice_params,
+                audio_config=audio_config
+            )
+            with open(output_path, "wb") as out:
+                out.write(response.audio_content)
+            return True
+        except Exception as e:
+            st.session_state.operation_status = {
+                "type": "error",
+                "message": "音訊生成發生錯誤！"
+            }
+            return False
+
+    def concatenate_audio(self) -> bool:
+        """
+        將 audio 資料夾中所有獨立的 .wav 檔，按檔名順序拼接成一個完整的音訊檔。
+        """
+        # 1. 檢查前置條件：使用我們之前建立的狀態檢查方法
+        if not self.has_sentence_audio():
+            st.session_state.operation_status = {
+                "type": "error",
+                "message": "錯誤：在 audio 資料夾中找不到任何 .wav 檔案，無法進行組合。"
+            }
+            return False
+
+        audio_dir = self.paths['audio']
+        output_path = self.paths['combined_audio']
+
+        try:
+            # 2. 獲取所有 .wav 檔案並進行排序
+            # 使用 sorted() 確保檔案是按字母順序（例如 000.wav, 001.wav, ...）處理的
+            wav_files = sorted(audio_dir.glob("*.wav"))
+            
+            if not wav_files:
+                st.session_state.operation_status = {
+                    "type": "error",
+                    "message": " audio 資料夾中找到了目錄，但沒有找到 .wav 檔案。"
+                }                
+                return False
+
+            # 3. 初始化一個空的 AudioSegment 作為拼接的基礎
+            # 這是比「拿第一個檔案當基礎」更穩健的做法
+            combined_audio = AudioSegment.empty()
+            
+            # 4. 遍歷所有音訊檔並依次拼接
+            for wav_file in wav_files:
+                # 讀取單個 .wav 檔案
+                segment = AudioSegment.from_wav(wav_file)
+                
+                # 使用 `+` 運算子將音訊片段拼接到末尾
+                combined_audio += segment
+
+            # 5. 匯出拼接好的完整音訊檔
+            # format="wav" 明確指定輸出格式
+            print(f"正在將組合音訊匯出到: {output_path}")
+            combined_audio.export(output_path, format="wav")
+            
+            return True
+
+        except FileNotFoundError:
+            st.session_state.operation_status = {
+                "type": "error",
+                "message": "FFmpeg 未安裝或未在系統路徑中。Pydub 需要它來處理音訊。"
+            }                
+            print("Pydub 錯誤：請確保 FFmpeg 已安裝並在系統的 PATH 環境變數中。")
+            return False
+        except Exception as e:
+            st.session_state.operation_status = {
+                "type": "error",
+                "message": f"組合音訊時發生未預期的錯誤: {e}"
+            }    
+            print(f"組合音訊時出錯: {e}")
+            return False
+
+    def generate_ass_subtitles(self) -> bool:
+        """
+        根據 data.json 的內容和 audio/ 目錄中每個音訊檔的時長，
+        生成一個包含多種樣式和四層字幕的 .ass 檔案。
+        此版本精確複製了新的 step5_generate_ass.py 的邏輯[1]。
+        """
+        # 1. 檢查前置條件
+        if not self.has_sentence_audio():
+            st.session_state.operation_status = {
+                "type": "error",
+                "message": "錯誤：找不到單句音訊檔，無法生成字幕。"
+            }
+            return False
+            
+        if not self.data:
+            st.session_state.operation_status = {
+                "type": "error",
+                "message": "錯誤：專案資料未載入。"
+            }
+            return False
+
+        # 2. 準備路徑和資料
+        ass_path = self.paths['ass_file']
+        audio_dir = self.paths['audio']
+
+        try:
+            # 從 self.data 讀取各語言的文本行
+            en_lines = [line.strip() for line in self.data.get("en", "").split('\n') if line.strip()]
+            zh_lines = [line.strip() for line in self.data.get("zh", "").split('\n') if line.strip()]
+            ipa_lines = [line.strip() for line in self.data.get("ipa", "").split('\n') if line.strip()]
+
+            # 3. 使用正規表示式獲取並排序音訊檔案
+            file_pattern = r"(\d{3})\.wav" # 根據您的腳本，檔名應為 vocab_00.wav, vocab_01.wav 等
+            pattern = re.compile(file_pattern)
+            wav_files = sorted(
+                [p for p in audio_dir.iterdir() if p.is_file() and pattern.fullmatch(p.name)],
+                key=lambda p: int(pattern.fullmatch(p.name).group(1))
+            )
+
+            # 4. 嚴格檢查資料數量是否一致
+            if not (len(wav_files) == len(en_lines) == len(zh_lines) == len(ipa_lines)):
+                msg = f"錯誤：資料數量不一致！音訊({len(wav_files)}), EN({len(en_lines)}), ZH({len(zh_lines)}), IPA({len(ipa_lines)})"
+                st.session_state.operation_status = {"type": "error", "message": msg}
+                return False
+
+            total_files = len(wav_files)
+            if total_files == 0:
+                st.session_state.operation_status = {"type": "warning", "message": "找不到任何匹配的音訊檔來生成字幕。"}
+                return False
+
+            # 5. 使用 pysubs2 建立 .ass 檔案物件
+            subs = pysubs2.SSAFile()
+            subs.info["PlayResX"] = "1920"
+            subs.info["PlayResY"] = "1080"
+            subs.info["Title"] = self.name
+
+            # 6. 定義所有需要的樣式 (從您的腳本中精確複製)[1]
+            subs.styles["EN"] = pysubs2.SSAStyle(fontname="Noto Sans", fontsize=140, primarycolor=pysubs2.Color(255, 248, 231), outlinecolor=pysubs2.Color(255, 248, 231), outline=2, alignment=pysubs2.Alignment.TOP_CENTER, marginv=280)
+            subs.styles["IPA"] = pysubs2.SSAStyle(fontname="Noto Sans", fontsize=110, primarycolor=pysubs2.Color(255, 140, 0), outlinecolor=pysubs2.Color(255, 140, 0), outline=1, alignment=pysubs2.Alignment.TOP_CENTER, marginv=340)
+            subs.styles["ZH"] = pysubs2.SSAStyle(fontname="Noto Sans TC", fontsize=140, primarycolor=pysubs2.Color(102, 128, 153), outlinecolor=pysubs2.Color(102, 128, 153), outline=1, alignment=pysubs2.Alignment.TOP_CENTER, marginv=440)
+            subs.styles["NUMBER"] = pysubs2.SSAStyle(fontname="Segoe UI Symbol", fontsize=120, primarycolor=pysubs2.Color(144, 144, 144), outlinecolor=pysubs2.Color(144, 144, 144), bold=True, outline=1, borderstyle=1,alignment=pysubs2.Alignment.TOP_RIGHT, marginl=0, marginr=260, marginv=160)
+
+            # 7. 遍歷音訊檔，生成四層字幕事件
+            st.session_state.operation_status = {
+                "type": "progress", "value": 0, "message": "正在準備生成字幕..."
+            }
+            current_time_ms = 0
+            for i, wav_path in enumerate(wav_files):
+                # 使用 librosa 獲取精確時長 (秒)，並轉換為毫秒
+                duration_ms = int(librosa.get_duration(path=str(wav_path)) * 1000)
+                
+                start_time = current_time_ms
+                end_time = current_time_ms + duration_ms
+
+                # 為每一層字幕建立一個事件
+                subs.append(pysubs2.SSAEvent(start=start_time, end=end_time, text=en_lines[i], style="EN"))
+                subs.append(pysubs2.SSAEvent(start=start_time, end=end_time, text=f"[{ipa_lines[i]}]", style="IPA"))
+                subs.append(pysubs2.SSAEvent(start=start_time, end=end_time, text=zh_lines[i], style="ZH"))
+                subs.append(pysubs2.SSAEvent(start=start_time, end=end_time, text=i, style="NUMBER"))
+
+                current_time_ms = end_time
+                st.session_state.operation_status = {
+                    "type": "progress",
+                    "value": (i + 1) / total_files,
+                    "message": f"正在處理字幕... ({i+1}/{total_files})"
+                }
+            # 8. 儲存 .ass 檔案
+            subs.save(str(ass_path))
+            st.session_state.operation_status = {
+                "type": "success",
+                "message": f"ASS 字幕檔已成功生成並儲存於 {ass_path.name}！🎉"
+            }
+            return True
+
+        except Exception as e:
+            st.session_state.operation_status = {
+                "type": "error",
+                "message": f"生成 ASS 字幕時發生未預期的錯誤: {e}"
+            }
+            return False
+
+    def has_sentence_audio(self) -> bool:
+        """檢查 audio 資料夾是否存在且包含 .wav 檔案。"""
+        audio_dir = self.paths.get('audio')
+        return audio_dir and audio_dir.exists() and any(f.suffix == '.wav' for f in audio_dir.iterdir())
+
+    def has_combined_audio(self) -> bool:
+        """檢查組合後的音訊檔是否存在。"""
+        combined_path = self.paths.get('combined_audio')
+        return combined_path and combined_path.exists()
+
+
+
+    def assemble_video(self, logo_video: Path, open_video: Path, end_video: Path):
+        """
+        使用 FFmpeg 的 xfade 濾鏡組裝最終影片，並在過程中統一影片屬性與進行色彩校正。
+        """
+        # --- 標準化設定 ---
+        TARGET_WIDTH = 1920
+        TARGET_HEIGHT = 1080
+        TARGET_FPS = 30
+
+        def escape_ffmpeg_path_for_filter(path: Path) -> str:
+            """為在 FFmpeg 濾鏡圖中安全使用而轉義路徑。"""
+            path_str = str(path.resolve())
+            if os.name == 'nt':
+                return path_str.replace('\\', '\\\\').replace(':', '\\:')
+            else:
+                return path_str.replace("'", "'\\\\\\''")    
+        try:
+            # --- 1. 路徑與檔案檢查 ---
+            output_dir = self.paths['output'] 
+            temp_video_dir = self.paths['temp_video'] 
+            audio_path =  self.paths['combined_audio']
+            ass_path = self.paths['ass_file']
+            final_video_path = self.paths['final_video']
+            bg_final_path = output_dir / "bg_final.mp4"
+            transition_duration = 1.0
+            print("111")
+            for file_path in [logo_video, open_video, end_video, audio_path, ass_path]:
+                if not file_path or not file_path.exists():
+                    st.session_state.operation_status = {
+                        "type": "error",
+                        "message": f"缺少必需的檔案: {e}"
+                    }
+                    return
+            print("222")
+            
+            base_videos = sorted([p for p in temp_video_dir.iterdir() if p.is_file() and p.suffix.lower() in ['.mp4', '.mov']])
+            if not base_videos:
+                st.session_state.operation_status = {
+                        "type": "error",
+                        "message": f"資料夾中沒有影片可供合成。: {e}"
+                    }
+                return 
+            print("333")
+            
+            
+            p_loop_count, error_msg = self.calculate_loop_count(transition_duration=transition_duration)
+            if error_msg:
+                # 如果計算出錯，拋出一個錯誤讓外層的 except 捕捉
+                raise ValueError(f"計算循環次數時失敗: {error_msg}")
+
+            print("444")
+            # --- 2. 一步式生成主要內容影片 (bg_final.mp4) ---
+            if not bg_final_path.exists():
+                print(f"⚙️ 準備一步式生成主要內容影片 (循環 {p_loop_count} 次)...")
+                
+                looped_video_list = base_videos * p_loop_count
+                inputs_cmd = []
+                for video_path in looped_video_list:
+                    inputs_cmd.extend(["-i", str(video_path)])
+                
+                inputs_cmd.extend(["-i", str(audio_path)])
+                ass_path_str = escape_ffmpeg_path_for_filter(ass_path)
+                
+                filter_parts = []
+                stream_count = len(looped_video_list)
+                
+                # 【核心修改】定義色彩校正濾鏡
+                color_correction_filter = "eq=brightness=-0.05:contrast=0.95:saturation=0.7"
+
+                # 將標準化 (尺寸、影格率) 與色彩校正合併
+                for i in range(stream_count):
+                    filter_parts.append(
+                        f"[{i}:v]scale={TARGET_WIDTH}:{TARGET_HEIGHT}:force_original_aspect_ratio=decrease,pad={TARGET_WIDTH}:{TARGET_HEIGHT}:(ow-iw)/2:(oh-ih)/2,setsar=1,fps={TARGET_FPS},{color_correction_filter}[v_scaled_{i}]"
+                    )
+                
+                last_v_out = "[v_scaled_0]"
+                for i in range(stream_count - 1):
+                    offset = sum(get_media_duration(v) for v in looped_video_list[:i+1]) - (i + 1) * transition_duration
+                    v_in_next = f"[v_scaled_{i+1}]"
+                    v_out_current = f"[v_out{i+1}]" if i < stream_count - 2 else "[bg_video_stream]"
+                    filter_parts.append(f"{last_v_out}{v_in_next}xfade=transition=fade:duration={transition_duration}:offset={offset:.4f}{v_out_current}")
+                    last_v_out = v_out_current
+
+                drawbox_filter = "drawbox=w=iw*0.8:h=ih*0.8:x=(iw-iw*0.8)/2:y=(ih-ih*0.8)/2:color=0x808080@0.7:t=fill"
+                filter_parts.append(f"[bg_video_stream]{drawbox_filter}[v_with_mask]")
+                filter_parts.append(f"[v_with_mask]ass=filename='{ass_path_str}'[final_v]")
+                filter_complex_str = ";".join(filter_parts)
+
+                ffmpeg_main_content_cmd = [
+                    "ffmpeg", "-y", *inputs_cmd,
+                    "-filter_complex", filter_complex_str,
+                    "-map", "[final_v]",
+                    "-map", f"{stream_count}:a:0",
+                    "-c:v", "libx264", "-pix_fmt", "yuv420p", "-preset", "fast",
+                    "-c:a", "aac", "-b:a", "192k",
+                    "-shortest",
+                    str(bg_final_path)
+                ]
+                
+                print("🚀 正在執行 FFmpeg 主要內容合成指令 (含色彩校正)...")
+                result = subprocess.run(ffmpeg_main_content_cmd, check=True, capture_output=True, text=True, encoding='utf-8')
+                if result.returncode != 0:
+                    raise subprocess.CalledProcessError(result.returncode, result.args, stderr=result.stderr)
+                print(f"✅ 主要內容影片已生成: {bg_final_path}")
+
+            # --- 3. 合成最終的影片序列 (logo -> open -> bg_final -> end) ---
+            if final_video_path.exists():
+                print(f"✅ 最終影片已存在，跳過組裝: {final_video_path}")
+                return True, f"✅ 影片已存在於 {final_video_path}", final_video_path
+
+            print("🎬 開始動態生成 xfade 合成指令...")
+            videos_to_concat = [logo_video, open_video, bg_final_path, end_video]
+            final_inputs_cmd, final_filter_parts, video_infos = [], [], []
+
+            for video_path in videos_to_concat:
+                final_inputs_cmd.extend(["-i", str(video_path)])
+                info = get_media_info(video_path)
+                video_infos.append(info)
+            
+            for i, info in enumerate(video_infos):
+                if not info["has_audio"]:
+                    duration = info['duration']
+                    final_filter_parts.append(f"anullsrc=r=44100:cl=stereo:d={duration:.4f}[silent_a_{i}]")
+
+            for i in range(len(videos_to_concat)):
+                # 注意：這裡我們不對 logo/open/end 影片進行調色，以保留它們的原始風格
+                final_filter_parts.append(
+                    f"[{i}:v]scale={TARGET_WIDTH}:{TARGET_HEIGHT}:force_original_aspect_ratio=decrease,pad={TARGET_WIDTH}:{TARGET_HEIGHT}:(ow-iw)/2:(oh-ih)/2,setsar=1,fps={TARGET_FPS}[v_final_scaled_{i}]"
+                )
+            
+            last_v_out = "[v_final_scaled_0]"
+            last_a_out = "[0:a]" if video_infos[0]["has_audio"] else "[silent_a_0]"
+
+            for i in range(len(videos_to_concat) - 1):
+                offset = sum(info['duration'] for info in video_infos[:i+1]) - (i + 1) * transition_duration
+                v_in_next = f"[v_final_scaled_{i+1}]"
+                a_in_next = f"[{i+1}:a]" if video_infos[i+1]["has_audio"] else f"[silent_a_{i+1}]"
+                
+                v_out_current = f"[v_out{i+1}]" if i < len(videos_to_concat) - 2 else "[video]"
+                a_out_current = f"[a_out{i+1}]" if i < len(videos_to_concat) - 2 else "[audio]"
+                
+                final_filter_parts.append(f"{last_v_out}{v_in_next}xfade=transition=fade:duration={transition_duration}:offset={offset:.4f}{v_out_current}")
+                final_filter_parts.append(f"{last_a_out}{a_in_next}acrossfade=d={transition_duration}{a_out_current}")
+                
+                last_v_out, last_a_out = v_out_current, a_out_current
+
+            final_filter_complex_str = ";".join(final_filter_parts)
+
+            ffmpeg_concat_cmd = [
+                "ffmpeg", "-y", *final_inputs_cmd,
+                "-filter_complex", final_filter_complex_str,
+                "-map", "[video]", "-map", "[audio]",
+                "-c:v", "libx264", "-pix_fmt", "yuv420p", "-preset", "fast",
+                "-movflags", "+faststart",
+                "-c:a", "aac", "-b:a", "192k",
+                str(final_video_path)
+            ]
+
+            print("🚀 執行 FFmpeg 最終序列合成指令...")
+            result = subprocess.run(ffmpeg_concat_cmd, check=True, capture_output=True, text=True, encoding='utf-8')
+            if result.returncode != 0:
+                raise subprocess.CalledProcessError(result.returncode, result.args, stderr=result.stderr)
+
+            print(f"✅ 影片已成功組裝並儲存至 {final_video_path}")
+            return True, f"✅ 影片已成功組裝並儲存至 {final_video_path}", final_video_path
+
+        except subprocess.CalledProcessError as e:
+            error_output = e.stderr if e.stderr else str(e)
+            return False, f"❌ FFmpeg 執行失敗:\n{error_output}", None
+        except Exception as e:
+            return False, f"❌ 發生未預期錯誤: {e}", None
+
+
+    # 【新增】計算循環次數 p 的函式
+    def calculate_loop_count(self, transition_duration: float) -> tuple[int | None, str | None]:
+        """
+        根據音訊長度和一系列影片，計算所需的最小循環次數 p。
+        成功時回傳 (p, None)，失敗時回傳 (None, error_message)。
+        """
+        print("aaa")
+        m_prime = get_media_duration(self.paths['combined_audio'])
+        if m_prime is None:
+            return None, "無法讀取音訊檔案長度。"
+        print("bbb")
+        video_folder=self.paths['temp_video']
+        video_paths = [p for p in video_folder.iterdir() if p.is_file() and p.suffix.lower() in ['.mp4', '.mov']]
+        video_lengths = [get_media_duration(p) for p in video_paths]
+        video_lengths = [l for l in video_lengths if l is not None and l > 0]
+        print("ccc")
+        if not video_lengths:
+            return None, "在 `test` 資料夾中找不到有效的影片檔案。"
+        print("ddd")
+        n = len(video_lengths)
+        m = sum(video_lengths)
+        tr = transition_duration
+
+        denominator = m - (n - 1) * tr
+        
+        if denominator <= 0:
+            return None, f"影片的有效長度 ({denominator:.2f}s) 小於或等於零，無法進行循環。請增加影片時長或減少轉場時間。"
+
+        p = math.ceil(m_prime / denominator)
+        return p, None
diff --git a/ui_fragments/audio_manager.py b/ui_fragments/audio_manager.py
index a1fce8f..433bb39 100644
--- a/ui_fragments/audio_manager.py
+++ b/ui_fragments/audio_manager.py
@@ -1,5 +1,5 @@
 import streamlit as st
-from utils.callbacks import toggle_all_audio_checkboxes, callback_delete_selected_audios
+from callbacks import toggle_all_audio_checkboxes, callback_delete_selected_audios
 
 @st.fragment
 def audio_management_fragment(paths: dict):
diff --git a/ui_fragments/tab0_data_processing.py b/ui_fragments/tab0_data_processing.py
new file mode 100644
index 0000000..3eb0d2c
--- /dev/null
+++ b/ui_fragments/tab0_data_processing.py
@@ -0,0 +1,38 @@
+# ui_fragments/tab_data_processing.py
+
+import streamlit as st
+import callbacks
+from project_model import Project # 引入 Project 以便進行型別註記
+
+@st.fragment
+def render_tab(project: Project):
+    """
+    負責顯示「1. 資料處理 & AI 加註」Tab 的所有 UI 元件和邏輯。
+    """
+    # 根據 project.data 的狀態來決定顯示哪個 UI
+    if project.data:
+        # --- 狀態一：專案「已同步」---
+        st.session_state.operation_status = {
+            "success": True, 
+            "message": "✅ 專案資料已就緒。"
+        }
+        with st.container(border=True):
+            col1, col2 = st.columns([3, 1])
+            with col1:
+                st.subheader("專案資料與 AI 加註")
+            with col2:
+                st.button("🔄 從 Notion 同步更新", on_click=callbacks.callback_sync_notion)
+            with st.expander("預覽專案資料", expanded=False):
+                st.json(project.data)
+        st.divider()
+        st.subheader("AI 自動加註")
+        # ... (AI 加註的按鈕和邏輯) ...
+        st.button("執行 AI 翻譯與音標加註並寫回 Notion", on_click=callbacks.callback_add_zh_ipa)
+
+    else:
+        # --- 狀態二：專案「僅初始化」---
+        st.info("ℹ️ 這個專案的框架已建立，請執行第一步來同步核心資料。")
+        st.button("🚀 步驟一：從 Notion 抓取專案資料", on_click=callbacks.callback_sync_notion, type="primary")
+
+    st.divider()
+    st.info("✍️ **人工檢查點**：\n\n1. 請確保 `Notion` 中的內容是您想要的最終版本。\n2. 修改完成後，記得點擊上方的同步按鈕。")
\ No newline at end of file
diff --git a/ui_fragments/tab1_asset_generation.py b/ui_fragments/tab1_asset_generation.py
new file mode 100644
index 0000000..9457024
--- /dev/null
+++ b/ui_fragments/tab1_asset_generation.py
@@ -0,0 +1,101 @@
+# utils/tab1_asset_generation.py
+
+import streamlit as st
+
+
+@st.fragment
+def render_tab(project, callbacks):
+    """
+    渲染「素材生成」標籤頁的 UI。
+
+    這個函式負責處理所有與音效生成和字幕檔生成相關的介面元件。
+
+    Args:
+        project: 存放專案狀態和路徑的物件。
+        callbacks: 存放按鈕回呼函式的物件。
+    """
+    # --- 音效生成區塊 ---
+    with st.container(border=True):
+        st.subheader("音效生成")
+        
+        # 步驟 3.1
+        st.markdown("##### 步驟 3.1: 生成單句音訊")
+        st.button("執行生成", on_click=callbacks.callback_generate_sentence_audio)
+        
+        st.divider()
+
+        # 步驟 3.2
+        st.markdown("##### 步驟 3.2: 組合完整音訊")
+        can_concatenate = project.has_sentence_audio()
+        
+        if not can_concatenate:
+            st.info("請先執行步驟 3.1 以生成單句音訊。")
+        
+        st.button("執行組合", on_click=callbacks.callback_concatenate_audio, disabled=not can_concatenate)
+        
+        if project.has_combined_audio():
+            st.session_state.operation_status = {
+                "success": True, 
+                "message": "🎉 完整音訊已組合成功！"
+            }
+            st.audio(str(project.paths['combined_audio']))
+        
+        audio_management_fragment(project,callbacks)
+
+    st.divider()
+
+    # --- 字幕生成區塊 ---
+    with st.container(border=True):
+        st.subheader("步驟 4: 生成 ASS 字幕檔")
+        can_generate_ass = project.has_sentence_audio()
+
+        if not can_generate_ass:
+            st.info("請先執行步驟 3.1 以生成字幕所需的時間戳。")
+        
+        st.button("📝 生成 .ass 字幕檔", on_click=callbacks.callback_generate_subtitles, disabled=not can_generate_ass)
+
+    st.divider()
+
+
+@st.fragment
+def audio_management_fragment(project,callbacks):
+    """A self-contained fragment for managing and deleting project audio files."""
+    with st.expander("🎧 管理專案音訊素材"):
+        paths = project.paths
+
+        audio_dir = paths["audio"]
+        output_dir = paths["output"]
+        
+        audio_files = []
+        if audio_dir.exists():
+            audio_files.extend(sorted(audio_dir.glob('*.wav')))
+        if output_dir.exists():
+            audio_files.extend(sorted(output_dir.glob('*.wav')))
+
+        if not audio_files:
+            st.info("專案的 `audio` 和 `output` 資料夾中目前沒有音訊檔。")
+        else:
+            all_selected = all(st.session_state.get(f"delete_audio_cb_{f.name}", False) for f in audio_files)
+            if st.session_state.get('select_all_audios', False) != all_selected:
+                st.session_state.select_all_audios = all_selected
+            
+            st.markdown("勾選您想要刪除的音訊檔案，然後點擊下方的按鈕。")
+            
+            st.checkbox(
+                "全選/取消全選",
+                key="select_all_audios",
+                on_change=callbacks.toggle_all_audio_checkboxes,
+                args=(audio_files,)
+            )
+            
+            with st.form("delete_audios_form"):
+                for audio_file in audio_files:
+                    file_size_kb = audio_file.stat().st_size / 1024
+                    label = f"**{audio_file.parent.name}/{audio_file.name}** ({file_size_kb:.2f} KB)"
+                    st.checkbox(label, key=f"delete_audio_cb_{audio_file.name}")
+                
+                submitted = st.form_submit_button("🟥 確認刪除選取的音訊", use_container_width=True, type="primary")
+
+                if submitted:
+                    callbacks.callback_delete_selected_audios(paths)
+                    st.rerun(scope="fragment")
\ No newline at end of file
diff --git a/ui_fragments/tab2_online_video_search.py b/ui_fragments/tab2_online_video_search.py
new file mode 100644
index 0000000..08bee38
--- /dev/null
+++ b/ui_fragments/tab2_online_video_search.py
@@ -0,0 +1,142 @@
+# utils/tab2_search_video.py
+
+import streamlit as st
+import os
+from pathlib import Path
+from utils.helpers import  analyze_ass_for_keywords, search_pixabay_videos, search_pexels_videos
+
+@st.fragment
+def render_tab(project,callbacks):
+    """一個用於從多個來源搜尋並下載影片的獨立UI片段。"""
+    paths = project.paths
+    st.header("步驟 5: 從線上圖庫搜尋影片素材")
+    pixabay_api_key = st.secrets.get("PIXABAY_API_KEY")
+    pexels_api_key = st.secrets.get("PEXELS_API_KEY")
+
+    if not pixabay_api_key and not pexels_api_key:
+        st.warning("請至少在 Streamlit secrets 中設定 `PIXABAY_API_KEY` 或 `PEXELS_API_KEY` 以使用此功能。")
+        return
+
+    st.subheader("5.1 搜尋影片")
+
+    # 【新增】影片來源選擇
+    available_sources = []
+    if pixabay_api_key: available_sources.append("Pixabay")
+    if pexels_api_key: available_sources.append("Pexels")
+    
+    if not available_sources:
+        st.session_state.operation_status = {
+            "success": False, 
+            "message": "沒有可用的影片來源 API 金鑰。"
+        }        
+        return
+
+    source_choice = st.radio(
+        "選擇影片來源:",
+        options=available_sources,
+        horizontal=True,
+        key="video_source_choice"
+    )
+
+    keywords = analyze_ass_for_keywords(paths)
+    default_query = keywords[0] if keywords else ""
+    
+    with st.form(key="search_form"):
+        col1, col2 = st.columns([4, 1])
+        with col1:
+            st.text_input(
+                "Search Videos", 
+                value=default_query,
+                key="search_query_input", 
+                placeholder="輸入關鍵字後按 Enter 或點擊右側按鈕搜尋",
+                label_visibility="collapsed"
+            )
+        with col2:
+            submitted = st.form_submit_button("🔍 搜尋影片", use_container_width=True)
+
+    if submitted:
+        with st.spinner("正在搜尋並過濾影片..."):
+            query = st.session_state.get("search_query_input", "")
+            
+            # 【修改】根據選擇呼叫對應的 API
+            if source_choice == "Pixabay":
+                success, message, results = search_pixabay_videos(pixabay_api_key, query)
+            elif source_choice == "Pexels":
+                success, message, results = search_pexels_videos(pexels_api_key, query)
+            else:
+                success, message, results = False, "未知的影片來源", []
+
+            st.session_state.operation_status = {"success": success, "message": message, "source": "search_videos"}
+            
+            # --- 【修改】資料標準化 ---
+            standardized_results = []
+            if success and results:
+                if source_choice == "Pixabay":
+                    for v in results:
+                        try:
+                            standardized_results.append({
+                                'id': f"pixabay-{v['id']}",
+                                'thumbnail_url': v['videos']['tiny']['thumbnail'],
+                                'video_url': v['videos']['large']['url'],
+                                'preview_url': v['videos']['tiny']['url'],
+                                'width': v['videos']['large']['width'],
+                                'height': v['videos']['large']['height']
+                            })
+                        except KeyError: continue
+                elif source_choice == "Pexels":
+                    for v in results:
+                        try:
+                            # 尋找合適的影片檔案連結
+                            video_link_hd = next((f['link'] for f in v['video_files'] if f.get('quality') == 'hd'), None)
+                            video_link_sd = next((f['link'] for f in v['video_files'] if f.get('quality') == 'sd'), None)
+                            
+                            # 優先使用 HD 畫質，若無則用 SD，再沒有就用第一個
+                            final_video_url = video_link_hd or video_link_sd or v['video_files'][0]['link']
+                            
+                            standardized_results.append({
+                                'id': f"pexels-{v['id']}",
+                                'thumbnail_url': v['image'],
+                                'video_url': final_video_url,
+                                'preview_url': video_link_sd or final_video_url, # 預覽用 SD 或更高畫質
+                                'width': v['width'],
+                                'height': v['height']
+                            })
+                        except (KeyError, IndexError): continue
+            
+            st.session_state.search_results = standardized_results
+            st.session_state.selected_videos = {str(v['id']): {"url": v['video_url'], "selected": False} for v in standardized_results}
+            st.session_state.active_preview_id = None
+    
+    if keywords and (keywords[1] or keywords[2]):
+        st.caption(f"建議關鍵字: `{keywords[1]}` `{keywords[2]}`")
+
+    st.divider()
+
+    if st.session_state.search_results:
+        st.subheader("5.2 選擇影片並下載")
+        st.button("📥 下載選取的影片到專案素材庫", on_click=callbacks.callback_download_videos, args=(paths,), help="將下方勾選的影片下載至目前專案的 `output/test` 資料夾，並自動循序命名。")
+ 
+        num_cols = 5
+        cols = st.columns(num_cols)
+        # 【修改】使用標準化後的結果進行渲染
+        for i, video in enumerate(st.session_state.search_results):
+            with cols[i % num_cols]:
+                with st.container(border=True):
+                    media_placeholder = st.empty()
+                    video_id_str = str(video['id'])
+                    
+                    if st.session_state.active_preview_id == video_id_str:
+                        media_placeholder.video(video['preview_url'])
+                        preview_button_text, preview_button_type = "⏹️ 停止預覽", "secondary"
+                    else:
+                        media_placeholder.image(video['thumbnail_url'], use_container_width=True)
+                        preview_button_text, preview_button_type = "▶️ 預覽", "primary"
+                    
+                    st.caption(f"ID: {video_id_str}")
+                    st.caption(f"尺寸: {video['width']}x{video['height']}")
+                        
+                    is_selected = st.checkbox("選取", key=f"select_{video_id_str}", value=st.session_state.selected_videos.get(video_id_str, {}).get('selected', False))
+                    if video_id_str in st.session_state.selected_videos:
+                        st.session_state.selected_videos[video_id_str]['selected'] = is_selected
+                        
+                    st.button(preview_button_text, key=f"preview_{video_id_str}", on_click=callbacks.callback_toggle_preview, args=(video_id_str,), use_container_width=True, type=preview_button_type)
\ No newline at end of file
diff --git a/ui_fragments/tab3_video_composition.py b/ui_fragments/tab3_video_composition.py
new file mode 100644
index 0000000..415e9ab
--- /dev/null
+++ b/ui_fragments/tab3_video_composition.py
@@ -0,0 +1,124 @@
+
+import streamlit as st
+from pathlib import Path
+from config import SHARED_ASSETS_DIR 
+
+@st.fragment
+def render_tab(project, callbacks):
+    """渲染「最終影片合成」標籤頁的 UI。"""
+    
+    _render_video_management_section(project, callbacks)
+    _render_shared_asset_uploader(callbacks)    
+    _render_shared_asset_selection(callbacks)
+
+    st.divider()
+
+@st.fragment
+def _render_video_management_section(project, callbacks):
+    """
+    一個私有的輔助函式，用於渲染影片管理的 UI 部分。
+    """
+    with st.expander("🎬 管理專案影片素材", expanded=False):
+        paths = project.paths
+        output_dir = paths.get("output", Path("./output")) # 使用 .get 提供預設值
+        video_files = []
+
+        if output_dir.exists():
+            video_files = sorted(
+                [f for f in output_dir.iterdir() if f.suffix.lower() in ['.mp4', '.mov']],
+                key=lambda f: f.stat().st_mtime,
+                reverse=True
+            )
+
+        if not video_files:
+            st.info("專案輸出資料夾 (`/output`) 中目前沒有影片檔。")
+        else:
+            st.markdown("勾選您想要刪除的影片，然後點擊下方的按鈕。")
+            
+            st.checkbox(
+                "全選/取消全選",
+                key="select_all_videos",
+                on_change=callbacks.toggle_all_video_checkboxes,
+                args=(video_files,)
+            )
+
+            for video_file in video_files:
+                file_size_mb = video_file.stat().st_size / (1024 * 1024)
+                st.checkbox(
+                    f"**{video_file.name}** ({file_size_mb:.2f} MB)",
+                    key=f"delete_cb_{video_file.name}"
+                )
+
+            st.button(
+                "🟥 確認刪除選取的影片",
+                on_click=callbacks.delete_selected_videos,
+                use_container_width=True,
+                type="primary"
+            )
+
+def _render_shared_asset_selection(callbacks):
+    """
+    一個私有的輔助函式，用於渲染共享素材選擇和上傳的 UI。
+    """
+    st.subheader("步驟 3.2: 選擇共享影片素材")
+    st.subheader("輔助工具")
+
+    
+    # 【改動 1】更健壯的檔案列表讀取方式
+    try:
+        shared_videos = [""] + sorted(
+            [f.name for f in SHARED_ASSETS_DIR.glob('*') if f.suffix.lower() in ['.mp4', '.mov']]
+        )
+    except Exception as e:
+        st.error(f"無法讀取共享素材庫 '{SHARED_ASSETS_DIR}': {e}")
+        shared_videos = [""]
+
+    with st.container(border=True):
+        st.markdown("##### 從共享素材庫中選擇影片")
+        c1, c2 = st.columns(2)
+        with c1:
+            logo_selection = st.selectbox("選擇 Logo 影片:", shared_videos, key="logo_select")
+            open_selection = st.selectbox("選擇開場影片:", shared_videos, key="open_select")
+        with c2:
+            end_selection = st.selectbox("選擇結尾影片:", shared_videos, key="end_select")
+        
+    st.subheader("步驟 3.2: 執行最終影片合成")
+    all_videos_selected = all([logo_selection, open_selection, end_selection])
+
+    if not all_videos_selected:
+        st.info("請從上方的下拉選單中選擇所有 Logo、開場和結尾影片以啟用合成按鈕。")
+
+
+    # 【核心改動】st.button 的呼叫現在非常簡潔
+    st.button(
+        "🎬 合成最終影片", 
+        on_click=callbacks.assemble_final_video, 
+        kwargs={
+            # 只傳遞 UI 直接相關的、最少的資訊 (檔名)
+            "logo_video_name": logo_selection,
+            "open_video_name": open_selection,
+            "end_video_name": end_selection
+        }, 
+        disabled=not all_videos_selected,
+        use_container_width=True
+    )
+
+            
+    # 將選擇的結果回傳給主函式
+    return logo_selection, open_selection, end_selection
+
+def _render_shared_asset_uploader(callbacks):
+    """一個私有的輔助函式，用於渲染共享素材上傳工具。"""
+    with st.expander("📂 管理與上傳共享素材", expanded=False):
+        st.markdown("這裡上傳的影片將存入 `shared_assets` 公共資料夾，可供所有專案重複使用。")
+        
+        st.file_uploader(
+            "上傳新的影片到共享素材庫",
+            type=["mp4", "mov"],
+            accept_multiple_files=True,
+            label_visibility="collapsed",
+            key="shared_video_uploader",
+            on_change=callbacks.upload_shared_videos
+        )
+ 
+        
\ No newline at end of file
diff --git a/ui_fragments/video_manager.py b/ui_fragments/video_manager.py
index 6994908..19cd429 100644
--- a/ui_fragments/video_manager.py
+++ b/ui_fragments/video_manager.py
@@ -1,5 +1,5 @@
 import streamlit as st
-from utils.callbacks import toggle_all_video_checkboxes, callback_delete_selected_videos
+from callbacks import toggle_all_video_checkboxes, callback_delete_selected_videos
 
 @st.fragment
 def video_management_fragment(paths):
diff --git a/ui_fragments/video_search.py b/ui_fragments/video_search.py
index 320f89f..290a2e4 100644
--- a/ui_fragments/video_search.py
+++ b/ui_fragments/video_search.py
@@ -1,6 +1,6 @@
 import streamlit as st
 from utils.helpers import  analyze_ass_for_keywords, search_pixabay_videos, search_pexels_videos
-from utils.callbacks import callback_download_videos, callback_toggle_preview
+from callbacks import callback_download_videos, callback_toggle_preview
 
 
 @st.fragment
diff --git a/utils/asset_manager.py b/utils/asset_manager.py
new file mode 100644
index 0000000..a4ee9ec
--- /dev/null
+++ b/utils/asset_manager.py
@@ -0,0 +1,45 @@
+# utils/asset_manager.py
+
+import streamlit as st
+from pathlib import Path
+from config import SHARED_ASSETS_DIR 
+
+
+def list_shared_videos() -> list[str]:
+    """列出所有共享影片的檔案名稱。"""
+    try:
+        if not SHARED_ASSETS_DIR.exists():
+            return []
+        
+        return sorted(
+            [f.name for f in SHARED_ASSETS_DIR.glob('*') if f.suffix.lower() in ['.mp4', '.mov']]
+        )
+    except Exception as e:
+        # 可以在這裡記錄錯誤日誌
+        st.error(f"讀取共享素材庫時出錯: {e}")
+        return []
+
+def save_uploaded_shared_videos(uploaded_files: list) -> tuple[int, list[str]]:
+    """
+    將上傳的檔案儲存到共享素材庫。
+    回傳 (成功數量, 錯誤訊息列表)。
+    """
+    if not uploaded_files:
+        return 0, []
+
+    saved_count = 0
+    errors = []
+    
+    try:
+        SHARED_ASSETS_DIR.mkdir(parents=True, exist_ok=True)
+        for uploaded_file in uploaded_files:
+            try:
+                with open(SHARED_ASSETS_DIR / uploaded_file.name, "wb") as f:
+                    f.write(uploaded_file.getbuffer())
+                saved_count += 1
+            except Exception as e:
+                errors.append(f"儲存 '{uploaded_file.name}' 時出錯: {e}")
+    except Exception as e:
+        errors.append(f"無法建立共享資料夾 '{SHARED_ASSETS_DIR}': {e}")
+        
+    return saved_count, errors
diff --git a/utils/callbacks.py b/utils/callbacks.py
deleted file mode 100644
index 73875b4..0000000
--- a/utils/callbacks.py
+++ /dev/null
@@ -1,251 +0,0 @@
-import streamlit as st
-from pathlib import Path
-from scripts.step1_notion_sync import create_project_from_page
-from utils.helpers import calculate_loop_count
-from scripts.step6_assemble_video import run_step6_assemble_video
-from utils.paths import PROJECTS_DIR
-import requests
-
-# --- 專案與流程控制 Callbacks ---
-def callback_set_project():
-    st.session_state.current_project = st.session_state.project_selector
-    st.session_state.final_video_path = None
-    st.session_state.show_video = False
-    st.session_state.operation_status = {}
-    st.session_state.active_preview_id = None
-
-def callback_create_project():
-    page_id = st.session_state.page_titles_map[st.session_state.selected_title]
-    with st.spinner("正在建立專案..."):
-        success, msg, new_project_name = create_project_from_page(api_key=st.secrets.get("NOTION_API_KEY"), page_id=page_id, project_name=st.session_state.selected_title, projects_dir=PROJECTS_DIR)
-        if success:
-            st.session_state.current_project = new_project_name
-            st.session_state.selected_title = ""
-            st.session_state.operation_status = {"success": success, "message": msg, "source": "create_project"}
-
-def callback_assemble_final_video(paths, **kwargs):
-    """
-    影片合成的專用「準備」回呼。
-    它會先計算循環次數 p，然後將任務轉交給通用的 callback_run_step。
-    """
-    # 步驟 1: 執行前置計算
-    st.write("⏳ 正在計算影片循環次數...") # 提供即時回饋
-    audio_path = paths["combined_audio"]
-    video_folder = paths["output"] / "test"
-    
-    p, error_msg = calculate_loop_count(audio_path, video_folder, 1.0)
-    
-    # 步驟 2: 檢查前置計算的結果
-    if error_msg:
-        st.session_state.operation_status = {"success": False, "message": f"❌ 無法合成影片: {error_msg}", "source": "assemble_video"}
-        return # 如果計算失敗，直接終止流程
-
-    # 步驟 3: 將計算結果加入到參數中，並轉交給通用執行器
-    kwargs["p_loop_count"] = p
-    
-    # 現在，我們呼叫標準的執行回呼，讓它來處理 spinner 和後續流程
-    callback_run_step(run_step6_assemble_video, **kwargs)
-
-def callback_run_step(step_function, source="unknown", **kwargs):
-    spinner_text = kwargs.pop("spinner_text", "正在處理中，請稍候...")
-    with st.spinner(spinner_text):
-        result = step_function(**kwargs)
-        if len(result) == 2: success, msg = result
-        elif len(result) == 3: success, msg, _ = result
-        else: success, msg = False, "步驟函式回傳格式不符！"
-        st.session_state.operation_status = {"success": success, "message": msg, "source": source}
-        if step_function == run_step6_assemble_video and success:
-            st.session_state.final_video_path = str(result[2])
-            st.session_state.show_video = True
-
-def callback_delete_selected_videos(paths: dict):
-    output_dir = paths["output"]
-    deleted_files_count = 0
-    errors = []
-    
-    files_to_delete = []
-    for key, value in st.session_state.items():
-        if key.startswith("delete_cb_") and value:
-            filename = key.replace("delete_cb_", "", 1)
-            files_to_delete.append(filename)
-
-    if not files_to_delete:
-        st.session_state.operation_status = {"success": True, "message": "🤔 沒有選擇任何要刪除的影片。", "source": "delete_videos"}
-        return
-
-    for filename in files_to_delete:
-        try:
-            file_path = output_dir / filename
-            if file_path.exists():
-                if st.session_state.get("final_video_path") and Path(st.session_state.final_video_path) == file_path:
-                    st.session_state.final_video_path = None
-                    st.session_state.show_video = False
-                
-                file_path.unlink()
-                deleted_files_count += 1
-                del st.session_state[f"delete_cb_{filename}"]
-        except Exception as e:
-            errors.append(f"刪除 {filename} 時出錯: {e}")
-
-    if errors:
-        message = f"❌ 刪除操作有誤。成功刪除 {deleted_files_count} 個檔案，但發生以下錯誤: " + ", ".join(errors)
-        st.session_state.operation_status = {"success": False, "message": message, "source": "delete_videos"}
-    else:
-        message = f"✅ 成功刪除 {deleted_files_count} 個影片。"
-        st.session_state.operation_status = {"success": True, "message": message, "source": "delete_videos"}
-
-def toggle_all_video_checkboxes(video_files):
-    select_all_state = st.session_state.get('select_all_videos', False)
-    for video_file in video_files:
-        st.session_state[f"delete_cb_{video_file.name}"] = select_all_state
-
-def callback_delete_selected_audios(paths: dict):
-    deleted_files_count = 0
-    errors = []
-    
-    files_to_delete_names = []
-    for key, value in st.session_state.items():
-        if key.startswith("delete_audio_cb_") and value:
-            filename = key.replace("delete_audio_cb_", "", 1)
-            files_to_delete_names.append(filename)
-
-    if not files_to_delete_names:
-        st.session_state.operation_status = {"success": True, "message": "🤔 沒有選擇任何要刪除的音訊。", "source": "delete_audios"}
-        return
-
-    audio_dir = paths["audio"]
-    output_dir = paths["output"]
-
-    for filename in files_to_delete_names:
-        try:
-            file_path_audio = audio_dir / filename
-            file_path_output = output_dir / filename
-            
-            file_path_to_delete = None
-            if file_path_audio.exists():
-                file_path_to_delete = file_path_audio
-            elif file_path_output.exists():
-                file_path_to_delete = file_path_output
-
-            if file_path_to_delete:
-                file_path_to_delete.unlink()
-                deleted_files_count += 1
-                del st.session_state[f"delete_audio_cb_{filename}"]
-            else:
-                errors.append(f"找不到檔案 {filename}。")
-
-        except Exception as e:
-            errors.append(f"刪除 {filename} 時出錯: {e}")
-
-    if errors:
-        message = f"❌ 刪除操作有誤。成功刪除 {deleted_files_count} 個檔案，但發生以下錯誤: " + ", ".join(errors)
-        st.session_state.operation_status = {"success": False, "message": message, "source": "delete_audios"}
-    else:
-        message = f"✅ 成功刪除 {deleted_files_count} 個音訊。"
-        st.session_state.operation_status = {"success": True, "message": message, "source": "delete_audios"}
-
-def toggle_all_audio_checkboxes(audio_files):
-    select_all_state = st.session_state.get('select_all_audios', False)
-    for audio_file in audio_files:
-        st.session_state[f"delete_audio_cb_{audio_file.name}"] = select_all_state
-
-def callback_toggle_preview(video_id):
-    if st.session_state.active_preview_id == video_id: st.session_state.active_preview_id = None
-    else: st.session_state.active_preview_id = video_id
-
-def callback_download_videos(paths: dict):
-    with st.spinner("正在下載影片，請稍候..."):
-        videos_to_download = {vid: info for vid, info in st.session_state.selected_videos.items() if info['selected']}
-        if not videos_to_download:
-            st.session_state.operation_status = {"success": False, "message": "尚未選擇任何影片。", "source": "download_videos"}
-            return
-
-        download_dir = paths["output"] / "test"
-        download_dir.mkdir(parents=True, exist_ok=True)
-        
-        # --- 循序命名邏輯 START ---
-        existing_files = list(download_dir.glob('*.mp4')) + list(download_dir.glob('*.mov'))
-        existing_numbers = []
-        for f in existing_files:
-            try:
-                # 從檔名 (不含副檔名) 中提取數字
-                existing_numbers.append(int(f.stem))
-            except ValueError:
-                # 忽略那些不是純數字的檔名
-                continue
-        
-        # 決定起始編號
-        start_counter = max(existing_numbers) + 1 if existing_numbers else 1
-        counter = start_counter
-        # --- 循序命名邏輯 END ---
-
-        total, download_count, errors = len(videos_to_download), 0, []
-        
-        for i, (video_id, info) in enumerate(videos_to_download.items()):
-            url = info['url']
-            original_path = Path(url)
-            
-            # 使用循序命名
-            new_video_name = f"{counter}{original_path.suffix}"
-            save_path = download_dir / new_video_name
-            
-            try:
-                if not save_path.exists():
-                    response = requests.get(url, stream=True)
-                    response.raise_for_status()
-                    with open(save_path, 'wb') as f:
-                        f.write(response.content)
-                    download_count += 1
-                    counter += 1 # 只有在成功下載後才增加計數器
-            except Exception as e:
-                errors.append(f"下載影片 {original_path.name} 失敗: {e}")
-        
-        if errors:
-            final_message = f"任務完成，但有 {len(errors)} 個錯誤。成功處理 {download_count}/{total} 個影片。\n" + "\n".join(errors)
-            st.session_state.operation_status = {"success": False, "message": final_message, "source": "download_videos"}
-        else:
-            final_message = f"任務完成！成功下載 {download_count}/{total} 個影片到專案的 `output/test` 資料夾，並已自動循序命名。"
-            st.session_state.operation_status = {"success": True, "message": final_message, "source": "download_videos"}
-
-@st.fragment
-def video_management_fragment(paths: dict):
-    """A self-contained fragment for managing and deleting project videos."""
-    with st.expander("🎬 管理專案影片素材"):
-        output_dir = paths["output"]
-        video_files = []
-        if output_dir.exists():
-            video_files = sorted(
-                [f for f in output_dir.iterdir() if f.suffix.lower() in ['.mp4', '.mov']],
-                key=lambda f: f.stat().st_mtime,
-                reverse=True
-            )
-
-        if not video_files:
-            st.info("專案輸出資料夾 (`/output`) 中目前沒有影片檔。")
-        else:
-            all_selected = all(st.session_state.get(f"delete_cb_{f.name}", False) for f in video_files)
-            if st.session_state.get('select_all_videos', False) != all_selected:
-                st.session_state.select_all_videos = all_selected
-
-            st.markdown("勾選您想要刪除的影片，然後點擊下方的按鈕。")
-            
-            st.checkbox(
-                "全選/取消全選", 
-                key="select_all_videos", 
-                on_change=toggle_all_video_checkboxes, 
-                args=(video_files,)
-            )
-            
-            with st.form("delete_videos_form"):
-                for video_file in video_files:
-                    file_size_mb = video_file.stat().st_size / (1024 * 1024)
-                    st.checkbox(
-                        f"**{video_file.name}** ({file_size_mb:.2f} MB)",
-                        key=f"delete_cb_{video_file.name}"
-                    )
-
-                submitted = st.form_submit_button("🟥 確認刪除選取的影片", use_container_width=True, type="primary")
-                
-                if submitted:
-                    callback_delete_selected_videos(paths)
-                    st.rerun(scope="fragment")
diff --git a/utils/helpers.py b/utils/helpers.py
index a6243d8..1a532dc 100644
--- a/utils/helpers.py
+++ b/utils/helpers.py
@@ -6,7 +6,7 @@ from pathlib import Path
 from notion_client import Client
 from notion_client.helpers import iterate_paginated_api
 import subprocess
-import math
+
 import librosa
 
 def get_media_info(media_path: Path) -> dict:
@@ -42,48 +42,26 @@ def get_media_duration(file_path: Path) -> float | None:
         print(f"無法讀取檔案 {file_path} 的時長: {e}")
         return None
 
-# 【新增】計算循環次數 p 的函式
-def calculate_loop_count(audio_path: Path, video_folder: Path, transition_duration: float) -> tuple[int | None, str | None]:
+
+def display_operation_status():
     """
-    根據音訊長度和一系列影片，計算所需的最小循環次數 p。
-    成功時回傳 (p, None)，失敗時回傳 (None, error_message)。
+    檢查 session_state 中是否有操作狀態訊息，
+    並使用 st.toast 顯示它，然後清除。
     """
-    m_prime = get_media_duration(audio_path)
-    if m_prime is None:
-        return None, "無法讀取音訊檔案長度。"
-
-    video_paths = [p for p in video_folder.iterdir() if p.is_file() and p.suffix.lower() in ['.mp4', '.mov']]
-    video_lengths = [get_media_duration(p) for p in video_paths]
-    video_lengths = [l for l in video_lengths if l is not None and l > 0]
-
-    if not video_lengths:
-        return None, "在 `test` 資料夾中找不到有效的影片檔案。"
-
-    n = len(video_lengths)
-    m = sum(video_lengths)
-    tr = transition_duration
-
-    denominator = m - (n - 1) * tr
-    
-    if denominator <= 0:
-        return None, f"影片的有效長度 ({denominator:.2f}s) 小於或等於零，無法進行循環。請增加影片時長或減少轉場時間。"
-
-    p = math.ceil(m_prime / denominator)
-    return p, None
-def display_global_status_message():
-    """
-    檢查會話狀態中是否存在任何操作狀態，如果存在則顯示它。
-    顯示後會立即清除狀態，以確保訊息只顯示一次。
-    """
-    if 'operation_status' in st.session_state and st.session_state.operation_status:
+    if "operation_status" in st.session_state and st.session_state.operation_status:
         status = st.session_state.operation_status
-        # 根據成功與否，選擇對應的訊息元件
-        if status.get("success"):
-            st.success(status["message"], icon="✅")
+        message_type = status.get("type", "info")
+        message = status.get("message", "")
+        
+        if message_type == "success":
+            st.toast(f"✅ {message}")
+        elif message_type == "error":
+            st.toast(f"❌ {message}")
         else:
-            st.error(status["message"], icon="❌")
-        # 清除狀態，避免在下一次刷新時重複顯示
-        st.session_state.operation_status = {}
+            st.toast(f"ℹ️ {message}")
+        
+        # 清除狀態，防止重複顯示
+        del st.session_state.operation_status
 
 
 def analyze_ass_for_keywords(paths: dict) -> list:
diff --git a/utils/paths.py b/utils/paths.py
index 4fed02e..1a2f55e 100644
--- a/utils/paths.py
+++ b/utils/paths.py
@@ -7,15 +7,35 @@ PROJECTS_DIR.mkdir(exist_ok=True)
 SHARED_ASSETS_DIR.mkdir(exist_ok=True)
 
 def get_project_paths(project_name: str) -> dict:
-    """為給定專案回傳一個包含所有重要路徑的字典。"""
+    """
+    為給定專案回傳一個包含所有重要路徑的字典。
+    這是一個純粹的、無副作用的函式，是路徑規則的「單一事實來源」。
+    """
     if not project_name:
         return {}
+    
     project_root = PROJECTS_DIR / project_name
+    output_dir = project_root / "output" # 將所有生成物放在 output 資料夾
+    
     return {
         "root": project_root,
         "data": project_root / "data.json",
-        "audio": project_root / "audio",
-        "output": project_root / "output",
-        "combined_audio": project_root / "output" / "combined_audio.wav",
-        "ass_file": project_root / "output" / f"{project_name}.ass"
-    }
\ No newline at end of file
+        "audio": project_root / "audio", # 原始音訊片段
+        "output": output_dir, # 輸出的根目錄
+        "temp_video":output_dir / "temp_video",
+        "combined_audio": output_dir / "combined_audio.wav",
+        "ass_file": output_dir / "subtitles.ass",
+        "final_video": output_dir / f"{project_name}_final_video.mp4"
+    }
+def get_project_list() -> list[str]:
+    """
+    掃描專案根目錄並回傳所有專案名稱的列表。
+    這將成為獲取專案列表的「單一事實來源」。
+    """
+    if not PROJECTS_DIR.is_dir():
+        PROJECTS_DIR.mkdir() # 如果根目錄不存在，就建立它
+        return []
+    # 確保只回傳目錄，並過濾掉像 .DS_Store 這樣的隱藏檔案
+    project_names = [d.name for d in PROJECTS_DIR.iterdir() if d.is_dir() and not d.name.startswith('.')]
+    project_names.sort() # 排序以獲得一致的顯示順序
+    return project_names
\ No newline at end of file