import gradio as gr
import numpy as np
from PIL import Image
import io
import base64
import tempfile
import os

def calculate_crop_box(image, target_ratio=1170/391):
    """
    計算保持目標比例的最大裁切框
    """
    width, height = image.size
    current_ratio = width / height
    
    if current_ratio > target_ratio:
        # 圖片較寬，需要裁切寬度
        new_width = int(height * target_ratio)
        left = (width - new_width) // 2
        top = 0
        right = left + new_width
        bottom = height
    else:
        # 圖片較高，需要裁切高度
        new_height = int(width / target_ratio)
        left = 0
        top = (height - new_height) // 2
        right = width
        bottom = top + new_height
    
    return (left, top, right, bottom)

def process_image(image, crop_data=None):
    """
    處理圖片：裁切並調整為目標尺寸，並保存為 JPG 格式
    """
    if image is None:
        return None, "請上傳圖片"
    
    # 如果有裁切數據，使用用戶選擇的區域
    if crop_data is not None:
        # Gradio 的 Image 組件在編輯模式下會返回包含裁切信息的數據
        # 這裡我們處理裁切後的圖片
        processed_image = image
    else:
        # 如果沒有裁切數據，自動計算最佳裁切區域
        crop_box = calculate_crop_box(image)
        processed_image = image.crop(crop_box)
    
    # 調整為目標尺寸
    target_size = (1170, 391)
    final_image = processed_image.resize(target_size, Image.Resampling.LANCZOS)
    
    # 轉換為 RGB 模式以確保 JPG 格式輸出
    if final_image.mode in ('RGBA', 'LA', 'P'):
        # 創建白色背景
        rgb_image = Image.new('RGB', final_image.size, (255, 255, 255))
        if final_image.mode == 'P':
            final_image = final_image.convert('RGBA')
        rgb_image.paste(final_image, mask=final_image.split()[-1] if final_image.mode == 'RGBA' else None)
        final_image = rgb_image
    
    # 保存為 JPG 格式的臨時檔案
    temp_file = tempfile.NamedTemporaryFile(delete=False, suffix='.jpg')
    final_image.save(temp_file.name, format='JPEG', quality=95, optimize=True)
    temp_file.close()
    
    return temp_file.name, f"圖片已處理完成！尺寸：{final_image.size}，格式：JPG"

def auto_crop_preview(image):
    """
    自動裁切預覽
    """
    if image is None:
        return None, "請上傳圖片"
    
    crop_box = calculate_crop_box(image)
    cropped = image.crop(crop_box)
    
    # 創建預覽圖片，顯示裁切區域
    preview = image.copy()
    from PIL import ImageDraw
    draw = ImageDraw.Draw(preview)
    
    # 繪製裁切框
    draw.rectangle(crop_box, outline="red", width=3)
    
    return preview, f"建議裁切區域：{crop_box}"

def create_crop_interface(image):
    """
    創建裁切界面，顯示帶有裁切框的圖片
    """
    if image is None:
        return None, "請先上傳圖片"
    
    # 計算建議的裁切區域
    crop_box = calculate_crop_box(image)
    left, top, right, bottom = crop_box
    
    # 創建帶有裁切框的預覽圖
    preview = image.copy()
    from PIL import ImageDraw, ImageFont
    draw = ImageDraw.Draw(preview)
    
    # 繪製裁切框
    draw.rectangle(crop_box, outline="red", width=5)
    
    # 添加半透明遮罩到裁切區域外
    overlay = Image.new('RGBA', image.size, (0, 0, 0, 100))
    mask = Image.new('RGBA', image.size, (0, 0, 0, 0))
    mask_draw = ImageDraw.Draw(mask)
    mask_draw.rectangle(crop_box, fill=(255, 255, 255, 255))
    
    # 創建最終預覽
    preview = Image.alpha_composite(preview.convert('RGBA'), overlay)
    preview = Image.alpha_composite(preview, Image.new('RGBA', image.size, (0, 0, 0, 0)))
    
    return preview.convert('RGB'), f"建議裁切區域：{crop_box}\n可以點擊「使用建議區域」或「自定義裁切」"

def custom_crop_with_coordinates(image, x, y, width, height):
    """
    使用自定義座標裁切圖片
    """
    if image is None:
        return None, "請先上傳圖片"
    
    try:
        # 確保座標在圖片範圍內
        img_width, img_height = image.size
        x = max(0, min(x, img_width))
        y = max(0, min(y, img_height))
        width = max(10, min(width, img_width - x))
        height = max(10, min(height, img_height - y))
        
        # 執行裁切
        cropped = image.crop((x, y, x + width, y + height))
        
        # 調整為目標尺寸
        target_size = (1170, 391)
        final_image = cropped.resize(target_size, Image.Resampling.LANCZOS)
        
        # 轉換為 RGB 並保存為 JPG
        if final_image.mode in ('RGBA', 'LA', 'P'):
            rgb_image = Image.new('RGB', final_image.size, (255, 255, 255))
            if final_image.mode == 'P':
                final_image = final_image.convert('RGBA')
            rgb_image.paste(final_image, mask=final_image.split()[-1] if final_image.mode == 'RGBA' else None)
            final_image = rgb_image
        
        # 保存為 JPG 檔案
        temp_file = tempfile.NamedTemporaryFile(delete=False, suffix='.jpg')
        final_image.save(temp_file.name, format='JPEG', quality=95, optimize=True)
        temp_file.close()
        
        return temp_file.name, f"自定義裁切完成！裁切區域：({x}, {y}, {width}, {height})"
    
    except Exception as e:
        return None, f"裁切失敗：{str(e)}"

def use_suggested_crop(image):
    """
    使用建議的裁切區域
    """
    if image is None:
        return None, "請先上傳圖片"
    
    crop_box = calculate_crop_box(image)
    cropped = image.crop(crop_box)
    
    # 調整為目標尺寸
    target_size = (1170, 391)
    final_image = cropped.resize(target_size, Image.Resampling.LANCZOS)
    
    # 轉換為 RGB 並保存為 JPG
    if final_image.mode in ('RGBA', 'LA', 'P'):
        rgb_image = Image.new('RGB', final_image.size, (255, 255, 255))
        if final_image.mode == 'P':
            final_image = final_image.convert('RGBA')
        rgb_image.paste(final_image, mask=final_image.split()[-1] if final_image.mode == 'RGBA' else None)
        final_image = rgb_image
    
    # 保存為 JPG 檔案
    temp_file = tempfile.NamedTemporaryFile(delete=False, suffix='.jpg')
    final_image.save(temp_file.name, format='JPEG', quality=95, optimize=True)
    temp_file.close()
    
    return temp_file.name, f"使用建議裁切區域完成！區域：{crop_box}"

# 創建 Gradio 界面
with gr.Blocks(title="圖片裁切工具", theme=gr.themes.Soft()) as demo:
    gr.Markdown("# 🖼️ 圖片裁切工具")
    gr.Markdown("### 將任意尺寸的圖片按 1170:391 比例裁切並調整為目標尺寸")
    
    with gr.Row():
        with gr.Column(scale=1):
            # 圖片上傳區域
            input_image = gr.Image(
                label="上傳圖片",
                type="pil",
                height=400,
                interactive=True
            )
            
            # 手動裁切圖片區域
            crop_image = gr.Image(
                label="手動裁切區域（點擊並拖拽選擇裁切區域）",
                type="pil", 
                height=400,
                interactive=True,
                visible=False
            )
            
            # 按鈕區域
            with gr.Row():
                preview_btn = gr.Button("🔍 顯示建議裁切區域", variant="secondary")
                suggest_btn = gr.Button("✅ 使用建議區域", variant="primary")
            
            with gr.Row():
                edit_btn = gr.Button("✏️ 自定義裁切", variant="secondary")
                reset_btn = gr.Button("🔄 重置", variant="secondary")
                
        with gr.Column(scale=1):
            # 輸出區域
            output_image = gr.Image(
                label="處理後圖片 (JPG格式)",
                type="filepath",
                height=400,
                interactive=False
            )
            
            # 下載按鈕
            download_btn = gr.DownloadButton(
                label="📥 下載 JPG 圖片",
                variant="primary",
                visible=False
            )
            
            # 狀態信息
            status_text = gr.Textbox(
                label="狀態",
                value="等待圖片上傳...",
                interactive=False
            )
    
    # 預覽功能
    with gr.Row():
        preview_image = gr.Image(
            label="裁切區域預覽（紅框顯示建議裁切區域）",
            type="pil",
            height=300,
            visible=False
        )
    
    # 使用說明
    with gr.Accordion("📖 使用說明", open=False):
        gr.Markdown("""
        ### 如何使用：
        1. **上傳圖片**：點擊上傳區域選擇您的圖片
        2. **查看建議**：點擊「顯示建議裁切區域」查看系統建議
        3. **選擇方式**：
           - 點擊「使用建議區域」直接使用系統建議
           - 點擊「自定義裁切」手動輸入座標和尺寸
        4. **下載結果**：點擊「下載 JPG 圖片」按鈕下載處理後的圖片
        
        ### 功能特色：
        - ✨ 自動計算最佳裁切比例 (1170:391)
        - 🎯 支援自定義座標裁切
        - 📏 保持目標比例的精確輸出
        - 🖼️ 輸出高品質 JPG 格式圖片
        - 💾 簡單的一鍵下載功能
        - 🔄 重置功能方便重新開始
        
        ### 自定義裁切說明：
        - **X, Y 座標**：裁切區域的左上角位置
        - **寬度, 高度**：裁切區域的大小
        - 最終輸出會調整為 1170×391 像素
        """)
    
    # 自定義裁切參數區域
    with gr.Row(visible=False) as custom_crop_row:
        gr.Markdown("### 🎯 自定義裁切參數")
        
    with gr.Row(visible=False) as crop_controls:
        with gr.Column():
            crop_x = gr.Number(
                label="X 座標 (左上角)",
                value=0,
                precision=0,
                minimum=0
            )
            crop_y = gr.Number(
                label="Y 座標 (左上角)", 
                value=0,
                precision=0,
                minimum=0
            )
        with gr.Column():
            crop_width = gr.Number(
                label="寬度",
                value=300,
                precision=0,
                minimum=10
            )
            crop_height = gr.Number(
                label="高度",
                value=100,
                precision=0,
                minimum=10
            )
        with gr.Column():
            apply_crop_btn = gr.Button("🎯 套用自定義裁切", variant="primary")
        
    
    # 事件綁定
    
    # 顯示建議裁切區域
    preview_btn.click(
        fn=create_crop_interface,
        inputs=[input_image],
        outputs=[preview_image, status_text]
    ).then(
        fn=lambda: gr.update(visible=True),
        outputs=[preview_image]
    )
    
    # 使用建議區域直接處理
    def suggest_and_download(image):
        if image is None:
            return None, "請先上傳圖片", gr.update(visible=False)
        
        result_path, status = use_suggested_crop(image)
        if result_path:
            return result_path, status, gr.update(visible=True, value=result_path)
        else:
            return None, status, gr.update(visible=False)
    
    suggest_btn.click(
        fn=suggest_and_download,
        inputs=[input_image],
        outputs=[output_image, status_text, download_btn]
    )
    
    # 顯示/隱藏自定義裁切控制項
    def toggle_custom_controls(image):
        if image is None:
            return gr.update(visible=False), gr.update(visible=False)
        
        # 獲取圖片尺寸以設定預設值
        width, height = image.size
        suggested_crop = calculate_crop_box(image)
        
        return (
            gr.update(visible=True),
            gr.update(visible=True)
        )
    
    edit_btn.click(
        fn=toggle_custom_controls,
        inputs=[input_image],
        outputs=[custom_crop_row, crop_controls]
    )
    
    # 套用自定義裁切
    def apply_custom_crop(image, x, y, width, height):
        if image is None:
            return None, "請先上傳圖片", gr.update(visible=False)
        
        result_path, status = custom_crop_with_coordinates(image, x, y, width, height)
        if result_path:
            return result_path, status, gr.update(visible=True, value=result_path)
        else:
            return None, status, gr.update(visible=False)
    
    apply_crop_btn.click(
        fn=apply_custom_crop,
        inputs=[input_image, crop_x, crop_y, crop_width, crop_height],
        outputs=[output_image, status_text, download_btn]
    )
    
    # 重置功能
    reset_btn.click(
        fn=lambda: (
            None, None, None, 
            gr.update(visible=False), 
            gr.update(visible=False), 
            gr.update(visible=False),
            gr.update(visible=False),
            "請上傳圖片"
        ),
        outputs=[
            input_image, crop_image, output_image, 
            preview_image, custom_crop_row, crop_controls,
            download_btn, status_text
        ]
    )
    
    # 當圖片上傳時自動更新狀態和建議值
    def update_on_upload(image):
        if image is None:
            return "請上傳圖片", 0, 0, 300, 100
        
        # 計算建議的裁切區域
        crop_box = calculate_crop_box(image)
        left, top, right, bottom = crop_box
        width = right - left
        height = bottom - top
        
        return (
            f"圖片已上傳！尺寸：{image.size[0]}×{image.size[1]}",
            left, top, width, height
        )
    
    input_image.change(
        fn=update_on_upload,
        inputs=[input_image],
        outputs=[status_text, crop_x, crop_y, crop_width, crop_height]
    )

# 啟動應用程式
if __name__ == "__main__":
    demo.launch(
        server_name="0.0.0.0",
        server_port=7860,
        share=True
    )