#!/usr/bin/env python
# -*- coding: utf-8 -*-
"""
文件编码转换工具
功能：检测并转换GBK/GB2312编码的源代码文件为UTF-8(无BOM)格式
使用方法：
  python convert_encoding.py
"""

import os
import sys
from pathlib import Path
from datetime import datetime

# 需要处理的文件扩展名
SOURCE_EXTENSIONS = ['.cpp', '.c', '.h', '.hpp', '.cc', '.cxx']

# 转换列表文件名
CONVERSION_LIST_FILE = 'encoding_conversion_list.txt'

# 要尝试的编码列表（按优先级）
ENCODINGS_TO_TRY = ['gbk', 'gb2312', 'gb18030', 'utf-8', 'utf-8-sig']


class EncodingConverter:
    """编码转换器类"""
    
    def __init__(self, root_dir):
        self.root_dir = Path(root_dir)
        self.conversion_list = []
        self.list_file = self.root_dir / CONVERSION_LIST_FILE
        
    def detect_encoding(self, file_path):
        """检测文件编码（通过尝试不同编码读取）"""
        for encoding in ENCODINGS_TO_TRY:
            try:
                with open(file_path, 'r', encoding=encoding) as f:
                    content = f.read()
                    # 检查是否包含中文字符
                    has_chinese = any('\u4e00' <= char <= '\u9fff' for char in content)
                    return encoding, has_chinese, content
            except (UnicodeDecodeError, LookupError):
                continue
        return None, False, None
    
    def has_bom(self, file_path):
        """检查文件是否有BOM标记"""
        try:
            with open(file_path, 'rb') as f:
                header = f.read(3)
                # UTF-8 BOM: EF BB BF
                return header == b'\xef\xbb\xbf'
        except:
            return False
    
    def scan_files(self):
        """扫描所有源代码文件"""
        print(f"开始扫描目录: {self.root_dir}")
        print(f"搜索文件类型: {', '.join(SOURCE_EXTENSIONS)}")
        print("-" * 80)
        
        file_count = 0
        for ext in SOURCE_EXTENSIONS:
            for file_path in self.root_dir.rglob(f"*{ext}"):
                # 跳过特定目录
                str_path = str(file_path)
                if any(skip in str_path for skip in ['.git', '__pycache__', 'node_modules', '.vs']):
                    continue
                
                file_count += 1
                if file_count % 50 == 0:
                    print(f"已扫描 {file_count} 个文件...", end='\r')
                
                encoding, has_chinese, content = self.detect_encoding(file_path)
                
                if encoding:
                    needs_conversion = False
                    reason = ""
                    
                    # 判断是否需要转换
                    if encoding in ['gbk', 'gb2312', 'gb18030']:
                        needs_conversion = True
                        reason = f"{encoding.upper()}"
                    elif encoding == 'utf-8-sig' or (encoding == 'utf-8' and self.has_bom(file_path)):
                        needs_conversion = True
                        reason = "UTF-8 with BOM"
                    
                    if needs_conversion:
                        relative_path = file_path.relative_to(self.root_dir)
                        self.conversion_list.append({
                            'path': str(file_path),
                            'relative_path': str(relative_path),
                            'encoding': encoding,
                            'reason': reason,
                            'has_chinese': has_chinese,
                            'converted': False,
                            'content': content
                        })
                        print(f"\n找到待转换: {relative_path} [{reason}]")
        
        print("\n" + "-" * 80)
        print(f"扫描完成！共扫描 {file_count} 个文件，找到 {len(self.conversion_list)} 个需要转换")
        return len(self.conversion_list)
    
    def save_list(self):
        """保存转换列表到文件"""
        try:
            with open(self.list_file, 'w', encoding='utf-8') as f:
                f.write(f"# 文件编码转换列表\n")
                f.write(f"# 生成时间: {datetime.now().strftime('%Y-%m-%d %H:%M:%S')}\n")
                f.write(f"# 总计: {len(self.conversion_list)} 个文件\n")
                f.write(f"# 格式: 相对路径 | 原编码 | 状态\n")
                f.write("#" + "=" * 78 + "\n\n")
                
                for item in self.conversion_list:
                    status = "✓ 已转换" if item['converted'] else "✗ 待转换"
                    f.write(f"{item['relative_path']} | {item['reason']} | {status}\n")
            
            print(f"转换列表已保存: {self.list_file}")
            return True
        except Exception as e:
            print(f"保存列表失败: {e}")
            return False
    
    def load_list(self):
        """加载转换列表"""
        if not self.list_file.exists():
            return False
        
        try:
            self.conversion_list = []
            with open(self.list_file, 'r', encoding='utf-8') as f:
                for line in f:
                    line = line.strip()
                    if not line or line.startswith('#'):
                        continue
                    
                    parts = [p.strip() for p in line.split('|')]
                    if len(parts) >= 3:
                        relative_path = parts[0]
                        file_path = self.root_dir / relative_path
                        
                        if file_path.exists():
                            encoding, has_chinese, content = self.detect_encoding(file_path)
                            self.conversion_list.append({
                                'path': str(file_path),
                                'relative_path': relative_path,
                                'encoding': encoding if encoding else 'unknown',
                                'reason': parts[1],
                                'has_chinese': has_chinese,
                                'converted': '已转换' in parts[2],
                                'content': content
                            })
            
            print(f"已加载转换列表: {len(self.conversion_list)} 个文件")
            return True
        except Exception as e:
            print(f"加载列表失败: {e}")
            return False
    
    def convert_file(self, file_info):
        """转换单个文件"""
        file_path = Path(file_info['path'])
        
        try:
            # 使用已读取的内容或重新读取
            content = file_info.get('content')
            if content is None:
                encoding = file_info['encoding']
                with open(file_path, 'r', encoding=encoding) as f:
                    content = f.read()
            
            # 写为UTF-8无BOM
            with open(file_path, 'w', encoding='utf-8') as f:
                f.write(content)
            
            # 验证
            try:
                with open(file_path, 'r', encoding='utf-8') as f:
                    f.read()
                
                # 检查是否还有BOM
                if not self.has_bom(file_path):
                    file_info['converted'] = True
                    return True, "成功"
                else:
                    return False, "仍有BOM"
            except UnicodeDecodeError:
                return False, "无法用UTF-8读取"
        
        except Exception as e:
            return False, str(e)
    
    def convert_one(self, index=0):
        """转换单个文件（测试用）"""
        if index >= len(self.conversion_list):
            print("索引超出范围")
            return False
        
        file_info = self.conversion_list[index]
        
        if file_info['converted']:
            print(f"\n文件已转换: {file_info['relative_path']}")
            return True
        
        print(f"\n准备转换测试文件:")
        print(f"  路径: {file_info['relative_path']}")
        print(f"  编码: {file_info['reason']}")
        print(f"  包含中文: {'是' if file_info['has_chinese'] else '否'}")
        
        success, msg = self.convert_file(file_info)
        
        if success:
            print(f"  ✓ 转换{msg}")
            self.save_list()
            print(f"\n请用 Visual Studio 打开以下文件检查:")
            print(f"  {file_info['path']}")
            return True
        else:
            print(f"  ✗ 转换失败: {msg}")
            return False
    
    def convert_all(self, skip_converted=True):
        """批量转换所有文件"""
        total = len(self.conversion_list)
        success_count = 0
        fail_count = 0
        skip_count = 0
        
        print(f"\n开始批量转换 {total} 个文件...")
        print("=" * 80)
        
        for i, file_info in enumerate(self.conversion_list, 1):
            rel_path = file_info['relative_path']
            
            if skip_converted and file_info['converted']:
                print(f"[{i}/{total}] 跳过: {rel_path}")
                skip_count += 1
                continue
            
            print(f"[{i}/{total}] 转换: {rel_path}", end=" ... ")
            success, msg = self.convert_file(file_info)
            
            if success:
                print("✓")
                success_count += 1
            else:
                print(f"✗ {msg}")
                fail_count += 1
        
        print("=" * 80)
        print(f"转换完成！")
        print(f"  成功: {success_count}")
        print(f"  失败: {fail_count}")
        print(f"  跳过: {skip_count}")
        
        self.save_list()
        return success_count, fail_count


def main():
    """主函数"""
    script_dir = Path(__file__).parent
    root_dir = script_dir.parent  # GeomativeStudio目录
    
    print("=" * 80)
    print("文件编码转换工具 - GBK/GB2312 转 UTF-8(无BOM)")
    print("=" * 80)
    print(f"项目根目录: {root_dir}\n")
    
    converter = EncodingConverter(root_dir)
    
    # 尝试加载已有列表
    list_loaded = converter.load_list()
    
    if not list_loaded:
        print("未找到转换列表，开始扫描...\n")
        count = converter.scan_files()
        
        if count == 0:
            print("\n未找到需要转换的文件！")
            return
        
        converter.save_list()
    
    # 主菜单
    while True:
        print("\n" + "=" * 80)
        print("请选择操作:")
        print("  1. 转换一个文件（测试）")
        print("  2. 批量转换所有文件")
        print("  3. 重新扫描")
        print("  4. 查看待转换列表")
        print("  0. 退出")
        print("=" * 80)
        
        choice = input("\n输入选项 (0-4): ").strip()
        
        if choice == '1':
            # 找第一个未转换的
            index = -1
            for i, item in enumerate(converter.conversion_list):
                if not item['converted']:
                    index = i
                    break
            
            if index == -1:
                print("\n所有文件都已转换！")
            else:
                converter.convert_one(index)
        
        elif choice == '2':
            print("\n⚠️  警告: 即将批量转换所有文件！")
            confirm = input("确认继续? (输入 yes 确认): ").strip().lower()
            if confirm == 'yes':
                converter.convert_all()
            else:
                print("已取消")
        
        elif choice == '3':
            print("\n重新扫描...")
            converter.conversion_list = []
            converter.scan_files()
            converter.save_list()
        
        elif choice == '4':
            print("\n待转换文件列表:")
            print("-" * 80)
            for i, item in enumerate(converter.conversion_list, 1):
                status = "✓" if item['converted'] else "✗"
                print(f"{status} [{i}] {item['relative_path']} ({item['reason']})")
            print("-" * 80)
        
        elif choice == '0':
            print("\n退出程序")
            break
        
        else:
            print("\n无效选项！")


if __name__ == '__main__':
    try:
        main()
    except KeyboardInterrupt:
        print("\n\n程序被中断")
        sys.exit(0)
    except Exception as e:
        print(f"\n程序出错: {e}")
        import traceback
        traceback.print_exc()
        sys.exit(1)