import openai
import gradio as gr
import fitz  # PyMuPDF
from openai import OpenAI
import os
import tempfile
import traceback

# 全域變數
api_key = ""
selected_model = "gpt-4"
summary_text = ""
client = None
pdf_text = ""

def set_api_key(user_api_key):
    """設定 OpenAI API Key 並初始化客戶端"""
    global api_key, client
    try:
        api_key = user_api_key.strip()
        if not api_key:
            return "❌ API Key 不能為空"
        
        client = OpenAI(api_key=api_key)
        
        # 測試 API Key 是否有效
        test_response = client.chat.completions.create(
            model="gpt-4",
            messages=[{"role": "user", "content": "你好"}],
            max_tokens=5
        )
        
        return "✅ API Key 已設定並驗證成功"
    except Exception as e:
        return f"❌ API Key 設定失敗: {str(e)}"

def set_model(model_name):
    """設定選擇的模型"""
    global selected_model
    selected_model = model_name
    return f"✅ 模型已選擇：{model_name}"

def extract_pdf_text(file_path):
    """從 PDF 文件中提取文字"""
    try:
        doc = fitz.open(file_path)
        text = ""
        for page_num, page in enumerate(doc):
            page_text = page.get_text()
            if page_text.strip():  # 只添加非空白頁面
                text += f"\n--- 第 {page_num + 1} 頁 ---\n"
                text += page_text
        doc.close()
        return text
    except Exception as e:
        return f"❌ PDF 解析錯誤: {str(e)}"

def generate_summary(pdf_file):
    """從 PDF 內容生成摘要"""
    global summary_text, pdf_text
    
    if not client:
        return "❌ 請先設定 OpenAI API Key"
    
    if not pdf_file:
        return "❌ 請先上傳 PDF 文件"
    
    try:
        # 從 PDF 提取文字
        pdf_text = extract_pdf_text(pdf_file.name)
        
        if not pdf_text.strip():
            return "⚠️ 無法解析 PDF 文字，可能為純圖片 PDF 或空白文件。"
        
        # 檢查文字長度，必要時截斷
        max_chars = 8000  # 為系統提示留出空間
        if len(pdf_text) > max_chars:
            pdf_text_truncated = pdf_text[:max_chars] + "\n\n[文本已截斷，僅顯示前 8000 字符]"
        else:
            pdf_text_truncated = pdf_text
        
        # 生成摘要
        response = client.chat.completions.create(
            model=selected_model,
            messages=[
                {
                    "role": "system", 
                    "content": """你是一個專業的文檔摘要助手。請將以下 PDF 內容整理為結構化的摘要：

1. 首先提供一個簡短的總體概述
2. 然後按照重要性列出主要重點（使用項目符號）
3. 如果有數據或統計信息，請特別標注
4. 如果有結論或建議，請單獨列出

請用繁體中文回答，保持專業且易於理解的語調。"""
                },
                {"role": "user", "content": pdf_text_truncated}
            ],
            temperature=0.3
        )
        
        summary_text = response.choices[0].message.content
        return summary_text
        
    except Exception as e:
        error_msg = f"❌ 摘要生成失敗: {str(e)}"
        print(f"錯誤詳情: {traceback.format_exc()}")
        return error_msg

def ask_question(user_question):
    """基於 PDF 內容回答問題"""
    if not client:
        return "❌ 請先設定 OpenAI API Key"
    
    if not summary_text and not pdf_text:
        return "❌ 請先生成 PDF 摘要"
    
    if not user_question.strip():
        return "❌ 請輸入問題"
    
    try:
        # 使用摘要和原始文本來提供更好的上下文
        context = f"PDF 摘要:\n{summary_text}\n\n原始內容（部分）:\n{pdf_text[:2000]}"
        
        response = client.chat.completions.create(
            model=selected_model,
            messages=[
                {
                    "role": "system", 
                    "content": f"""你是一個專業的文檔問答助手。請基於提供的 PDF 內容回答用戶問題。

規則：
1. 只根據提供的文檔內容回答
2. 如果文檔中沒有相關信息，請明確說明
3. 引用具體的文檔內容來支持你的回答
4. 用繁體中文回答
5. 保持客觀和準確

文檔內容：
{context}"""
                },
                {"role": "user", "content": user_question}
            ],
            temperature=0.2
        )
        
        return response.choices[0].message.content
        
    except Exception as e:
        error_msg = f"❌ 問答生成失敗: {str(e)}"
        print(f"錯誤詳情: {traceback.format_exc()}")
        return error_msg

def clear_all():
    """清除所有資料"""
    global summary_text, pdf_text
    summary_text = ""
    pdf_text = ""
    return "", "", ""

# 創建 Gradio 介面
with gr.Blocks(
    theme=gr.themes.Soft(), 
    title="PDF 摘要助手",
    css="""
    /* 修復頁面大小問題 */
    .gradio-container {
        max-width: none !important;
        width: 100% !important;
        background: linear-gradient(135deg, #667eea 0%, #764ba2 100%) !important;
        min-height: 100vh !important;
        padding: 0 !important;
        margin: 0 !important;
    }
    
    /* 主要內容區域 - 修復大小問題 */
    .main-content {
        background: rgba(255, 255, 255, 0.95) !important;
        border-radius: 20px !important;
        margin: 20px auto !important;
        padding: 30px !important;
        box-shadow: 0 20px 40px rgba(0, 0, 0, 0.1) !important;
        backdrop-filter: blur(10px) !important;
        max-width: 1400px !important;
        width: calc(100% - 40px) !important;
    }
    
    /* 標題樣式 */
    .main-header {
        background: linear-gradient(135deg, #667eea 0%, #764ba2 100%) !important;
        -webkit-background-clip: text !important;
        -webkit-text-fill-color: transparent !important;
        background-clip: text !important;
        text-align: center !important;
        font-size: 2.5em !important;
        font-weight: bold !important;
        margin-bottom: 20px !important;
    }
    
    /* 分頁導航 - 修復點擊問題 */
    .gradio-tabs {
        border-radius: 15px !important;
        overflow: hidden !important;
    }
    
    .gradio-tabitem {
        padding: 25px !important;
        background: white !important;
        border-radius: 0 0 15px 15px !important;
    }
    
    /* 輸入框樣式 - 修復交互問題 */
    input[type="text"], 
    input[type="password"], 
    textarea {
        border: 2px solid #e0e6ff !important;
        border-radius: 12px !important;
        padding: 15px !important;
        font-size: 16px !important;
        transition: all 0.3s ease !important;
        width: 100% !important;
        box-sizing: border-box !important;
    }
    
    input[type="text"]:focus, 
    input[type="password"]:focus, 
    textarea:focus {
        border-color: #667eea !important;
        box-shadow: 0 0 20px rgba(102, 126, 234, 0.3) !important;
        outline: none !important;
    }
    
    /* 按鈕樣式 - 修復點擊問題 */
    button, 
    .gr-button,
    input[type="submit"],
    input[type="button"] {
        background: linear-gradient(135deg, #667eea 0%, #764ba2 100%) !important;
        border: none !important;
        border-radius: 12px !important;
        color: white !important;
        font-weight: 600 !important;
        padding: 15px 30px !important;
        font-size: 16px !important;
        transition: all 0.3s ease !important;
        box-shadow: 0 5px 15px rgba(102, 126, 234, 0.4) !important;
        cursor: pointer !important;
        pointer-events: auto !important;
        z-index: 1000 !important;
        position: relative !important;
        display: inline-block !important;
        min-height: 44px !important;
        line-height: normal !important;
    }
    
    button:hover, 
    .gr-button:hover,
    input[type="submit"]:hover,
    input[type="button"]:hover {
        transform: translateY(-2px) !important;
        box-shadow: 0 8px 25px rgba(102, 126, 234, 0.6) !important;
        background: linear-gradient(135deg, #5a6fd8 0%, #6a4190 100%) !important;
    }
    
    button:active, 
    .gr-button:active,
    input[type="submit"]:active,
    input[type="button"]:active {
        transform: translateY(0px) !important;
        box-shadow: 0 3px 10px rgba(102, 126, 234, 0.4) !important;
    }
    
    /* 次要按鈕樣式 */
    button[data-testid*="secondary"],
    .gr-button.secondary,
    button.secondary {
        background: linear-gradient(135deg, #f093fb 0%, #f5576c 100%) !important;
    }
    
    button[data-testid*="secondary"]:hover,
    .gr-button.secondary:hover,
    button.secondary:hover {
        background: linear-gradient(135deg, #e081e9 0%, #e3455a 100%) !important;
    }
    
    /* 修復 Gradio 特定的按鈕容器 */
    .gr-form > div,
    .gr-button-group,
    div[data-testid="button"] {
        pointer-events: auto !important;
        z-index: 999 !important;
    }
    
    /* 確保按鈕內的文字可點擊 */
    button span,
    .gr-button span {
        pointer-events: none !important;
        user-select: none !important;
    }
    
    /* 文件上傳區域 */
    .file-upload-area {
        border: 3px dashed #667eea !important;
        border-radius: 15px !important;
        background: rgba(102, 126, 234, 0.05) !important;
        padding: 40px !important;
        text-align: center !important;
        transition: all 0.3s ease !important;
        min-height: 120px !important;
    }
    
    .file-upload-area:hover {
        background: rgba(102, 126, 234, 0.1) !important;
        border-color: #764ba2 !important;
    }
    
    /* 單選按鈕容器 */
    .radio-group {
        background: rgba(102, 126, 234, 0.05) !important;
        border-radius: 12px !important;
        padding: 20px !important;
        margin: 10px 0 !important;
    }
    
    /* 輸出文本區域 */
    .output-text {
        background: #f8f9ff !important;
        border: 1px solid #e0e6ff !important;
        border-radius: 12px !important;
        padding: 20px !important;
        min-height: 200px !important;
    }
    
    /* 隱藏 Gradio logo 和 footer */
    footer,
    .gradio-container footer,
    div[class*="footer"],
    div[class*="Footer"],
    .gr-footer {
        display: none !important;
    }
    
    /* 修復響應式問題 */
    .gr-row {
        display: flex !important;
        gap: 20px !important;
        width: 100% !important;
    }
    
    .gr-column {
        flex: 1 !important;
        min-width: 0 !important;
    }
    
    /* 確保所有交互元素正常工作 */
    * {
        pointer-events: auto !important;
    }
    
    /* 特殊修復：覆蓋可能的 Gradio 樣式衝突 */
    .gradio-container * {
        pointer-events: auto !important;
    }
    
    /* 修復單選按鈕 */
    input[type="radio"] {
        pointer-events: auto !important;
        cursor: pointer !important;
        z-index: 1000 !important;
        position: relative !important;
    }
    
    /* 修復文件上傳 */
    input[type="file"] {
        pointer-events: auto !important;
        cursor: pointer !important;
        z-index: 1000 !important;
    }
    
    /* 添加 JavaScript 來確保按鈕響應 */
    </style>
    <script>
    document.addEventListener('DOMContentLoaded', function() {
        // 確保所有按鈕都可以點擊
        function fixButtons() {
            const buttons = document.querySelectorAll('button, input[type="submit"], input[type="button"]');
            buttons.forEach(btn => {
                btn.style.pointerEvents = 'auto';
                btn.style.cursor = 'pointer';
                btn.style.zIndex = '1000';
                btn.style.position = 'relative';
            });
        }
        
        // 初始修復
        fixButtons();
        
        // 定期檢查並修復新出現的按鈕
        setInterval(fixButtons, 1000);
        
        // 監聽 DOM 變化
        const observer = new MutationObserver(fixButtons);
        observer.observe(document.body, { 
            childList: true, 
            subtree: true 
        });
    });
    </script>
    <style>
    
    /* 響應式設計 */
    @media (max-width: 768px) {
        .main-content {
            margin: 10px !important;
            padding: 20px !important;
            width: calc(100% - 20px) !important;
        }
        
        .main-header {
            font-size: 1.8em !important;
        }
        
        .gr-row {
            flex-direction: column !important;
        }
        
        button {
            width: 100% !important;
            margin: 5px 0 !important;
        }
    }
    """
) as demo:
    with gr.Column(elem_classes="main-content"):
        gr.HTML("""
        <div class="main-header">📄 PDF 摘要 & 問答助手</div>
        
        <div style="text-align: center; margin-bottom: 30px; padding: 25px; background: linear-gradient(135deg, rgba(102, 126, 234, 0.1) 0%, rgba(118, 75, 162, 0.1) 100%); border-radius: 15px; border-left: 5px solid #667eea;">
            <h3 style="color: #667eea; margin-bottom: 15px;">🚀 歡迎使用 PDF 智能分析工具！</h3>
            <div style="display: flex; justify-content: space-around; flex-wrap: wrap; margin: 20px 0;">
                <div style="margin: 10px; padding: 15px; background: white; border-radius: 10px; box-shadow: 0 3px 10px rgba(0,0,0,0.1); min-width: 200px;">
                    <div style="font-size: 24px; margin-bottom: 10px;">📋</div>
                    <strong>智能摘要生成</strong><br>
                    <span style="color: #666;">自動分析 PDF 內容並生成結構化摘要</span>
                </div>
                <div style="margin: 10px; padding: 15px; background: white; border-radius: 10px; box-shadow: 0 3px 10px rgba(0,0,0,0.1); min-width: 200px;">
                    <div style="font-size: 24px; margin-bottom: 10px;">🤖</div>
                    <strong>AI 問答系統</strong><br>
                    <span style="color: #666;">基於文檔內容回答您的問題</span>
                </div>
                <div style="margin: 10px; padding: 15px; background: white; border-radius: 10px; box-shadow: 0 3px 10px rgba(0,0,0,0.1); min-width: 200px;">
                    <div style="font-size: 24px; margin-bottom: 10px;">💡</div>
                    <strong>快速理解</strong><br>
                    <span style="color: #666;">快速掌握長篇文檔的核心內容</span>
                </div>
            </div>
            <div style="background: rgba(255, 193, 7, 0.1); padding: 15px; border-radius: 10px; border-left: 4px solid #ffc107; margin-top: 20px;">
                <strong style="color: #e65100;">⚠️ 重要提醒：</strong> 使用前請先在「🔧 設定」頁面輸入您的 OpenAI API Key
            </div>
        </div>
        """)
    
        with gr.Tab("🔧 設定", elem_classes="settings-tab"):
            gr.Markdown("### ⚙️ 基本設定")
            with gr.Row():
                with gr.Column():
                    api_key_input = gr.Textbox(
                        label="🔑 輸入 OpenAI API Key", 
                        type="password",
                        placeholder="請輸入您的 OpenAI API Key (sk-...)",
                        elem_classes="api-input"
                    )
                    api_key_status = gr.Textbox(
                        label="📊 API 連接狀態", 
                        interactive=False,
                        value="🔄 等待設定 API Key...",
                        elem_classes="status-display"
                    )
                
                with gr.Column():
                    model_choice = gr.Radio(
                        ["gpt-4", "gpt-4.1", "gpt-4.5"], 
                        label="🤖 選擇 AI 模型",
                        value="gpt-4",
                        elem_classes="model-selector"
                    )
                    model_status = gr.Textbox(
                        label="🎯 當前模型", 
                        interactive=False,
                        value="✅ 已選擇：gpt-4",
                        elem_classes="status-display"
                    )
            
            # 添加測試按鈕
            gr.HTML("<div style='margin: 20px 0; padding: 15px; background: rgba(102, 126, 234, 0.1); border-radius: 10px;'><strong>💡 提示：</strong> 設定完成後，請前往「PDF 處理」頁面上傳文件開始使用！</div>")
    
        with gr.Tab("📄 PDF 處理", elem_classes="pdf-tab"):
            gr.Markdown("### 📁 文件上傳與摘要生成")
            with gr.Row():
                with gr.Column():
                    pdf_upload = gr.File(
                        label="📎 選擇 PDF 文件",
                        file_types=[".pdf"],
                        elem_classes="file-upload"
                    )
                    gr.Markdown("**支援格式**：PDF 文件 (建議 < 10MB)")
                    
                    with gr.Row():
                        summary_btn = gr.Button(
                            "🔄 開始生成摘要", 
                            variant="primary",
                            elem_classes="primary-btn"
                        )
                        clear_btn = gr.Button(
                            "🗑️ 清除所有資料", 
                            variant="secondary",
                            elem_classes="secondary-btn"
                        )
                
                with gr.Column():
                    summary_output = gr.Textbox(
                        label="📋 AI 生成的文檔摘要",
                        lines=15,
                        placeholder="📄 上傳 PDF 文件並點擊「開始生成摘要」按鈕，AI 將為您分析文檔內容...",
                        elem_classes="summary-output"
                    )
    
        with gr.Tab("❓ 智能問答", elem_classes="qa-tab"):
            gr.Markdown("### 💬 基於文檔內容的 AI 問答")
            with gr.Row():
                with gr.Column():
                    question_input = gr.Textbox(
                        label="💭 請輸入您的問題",
                        placeholder="例如：這份文件的主要結論是什麼？文中提到的關鍵數據有哪些？",
                        lines=3,
                        elem_classes="question-input"
                    )
                    question_btn = gr.Button(
                        "📤 發送問題", 
                        variant="primary",
                        elem_classes="primary-btn"
                    )
                    
                    gr.Markdown("""
                    **💡 問題範例：**
                    - 這份文件討論的主要議題是什麼？
                    - 文中有哪些重要的統計數據？
                    - 作者的主要觀點和結論是什麼？
                    - 文件中提到的建議有哪些？
                    """)
                
                with gr.Column():
                    answer_output = gr.Textbox(
                        label="🤖 AI 智能回答",
                        lines=12,
                        placeholder="🤖 請先上傳並生成 PDF 摘要，然後在左側輸入問題，AI 將基於文檔內容為您提供詳細回答...",
                        elem_classes="answer-output"
                    )
    
    # 事件處理器
    api_key_input.submit(set_api_key, inputs=api_key_input, outputs=api_key_status)
    model_choice.change(set_model, inputs=model_choice, outputs=model_status)
    summary_btn.click(generate_summary, inputs=pdf_upload, outputs=summary_output)
    question_btn.click(ask_question, inputs=question_input, outputs=answer_output)
    question_input.submit(ask_question, inputs=question_input, outputs=answer_output)
    clear_btn.click(clear_all, outputs=[summary_output, question_input, answer_output])

if __name__ == "__main__":
    # Hugging Face Spaces 部署設定
    demo.launch(
        share=False,  # Hugging Face Spaces 不需要 share
        show_api=False,
        show_error=True
    )