"""Obsidian KB - Git 同步"""

import os
import subprocess
from pathlib import Path
from typing import Optional, List
from datetime import datetime

from .config import get_config


class GitSync:
    """Git仓库同步管理"""
    
    def __init__(self, repo_path: Optional[str] = None):
        config = get_config()
        self.repo_path = repo_path or config.obsidian_path
        self.git_url = config.git_repo
        self.git_token = config.git_token
    
    def _run_git(self, args: List[str], cwd: Optional[str] = None) -> tuple[int, str, str]:
        """运行git命令"""
        cmd = ['git'] + args
        try:
            result = subprocess.run(
                cmd,
                cwd=cwd or self.repo_path,
                capture_output=True,
                text=True,
                encoding='utf-8'
            )
            return result.returncode, result.stdout, result.stderr
        except Exception as e:
            return -1, "", str(e)
    
    def is_git_repo(self) -> bool:
        """检查是否为git仓库"""
        git_dir = os.path.join(self.repo_path, '.git')
        return os.path.isdir(git_dir)
    
    def init_repo(self) -> bool:
        """初始化git仓库"""
        if self.is_git_repo():
            return True
        
        os.makedirs(self.repo_path, exist_ok=True)
        
        # git init
        code, _, _ = self._run_git(['init'])
        if code != 0:
            return False
        
        # 配置git用户（使用默认值）
        self._run_git(['config', 'user.email', 'obsidian-kb@localhost'])
        self._run_git(['config', 'user.name', 'Obsidian KB'])
        
        # 添加remote
        if self.git_url:
            # 如果提供了token，构建带认证的URL
            if self.git_token:
                auth_url = self._build_auth_url(self.git_url, self.git_token)
                self._run_git(['remote', 'add', 'origin', auth_url])
            else:
                self._run_git(['remote', 'add', 'origin', self.git_url])
        
        return True
    
    def _build_auth_url(self, url: str, token: str) -> str:
        """构建带认证的git URL"""
        if url.startswith('https://github.com/'):
            return url.replace('https://', f'https://x-access-token:{token}@')
        elif url.startswith('https://'):
            return url.replace('https://', f'https://oauth2:{token}@')
        return url
    
    def add_files(self, files: List[str]) -> bool:
        """添加文件到暂存区"""
        if not files:
            return True
        
        # 添加所有指定文件
        for file_path in files:
            # 转换为相对路径
            rel_path = os.path.relpath(file_path, self.repo_path)
            code, _, _ = self._run_git(['add', rel_path])
            if code != 0:
                return False
        
        return True
    
    def add_all(self) -> bool:
        """添加所有变更"""
        code, _, _ = self._run_git(['add', '.'])
        return code == 0
    
    def has_changes(self) -> bool:
        """检查是否有未提交的变更"""
        code, stdout, _ = self._run_git(['status', '--porcelain'])
        if code != 0:
            return False
        return bool(stdout.strip())
    
    def commit(self, message: Optional[str] = None, content_title: Optional[str] = None) -> bool:
        """提交变更"""
        if not self.has_changes():
            return True
        
        if not message:
            message = self._generate_commit_message(content_title)
        
        code, _, _ = self._run_git(['commit', '-m', message])
        return code == 0
    
    def _generate_commit_message(self, content_title: Optional[str] = None) -> str:
        """生成提交信息"""
        timestamp = datetime.now().strftime('%Y-%m-%d %H:%M')
        if content_title:
            return f"Add: {content_title[:50]}" + ("..." if len(content_title) > 50 else "") + f" [{timestamp}]"
        return f"Update KB notes [{timestamp}]"
    
    def push(self, branch: str = 'main') -> bool:
        """推送到远程"""
        # 检查是否有origin
        code, stdout, _ = self._run_git(['remote'])
        if code != 0 or 'origin' not in stdout:
            return False
        
        # 检查分支是否存在，不存在则创建
        code, stdout, _ = self._run_git(['branch', '--show-current'])
        current_branch = stdout.strip()
        
        if not current_branch:
            # 创建初始分支
            self._run_git(['checkout', '-b', branch])
        
        # 推送
        code, _, _ = self._run_git(['push', '-u', 'origin', branch])
        return code == 0
    
    def pull(self, branch: str = 'main') -> bool:
        """从远程拉取"""
        code, _, _ = self._run_git(['pull', 'origin', branch])
        return code == 0
    
    def sync(self, files: Optional[List[str]] = None, content_title: Optional[str] = None) -> tuple[bool, str]:
        """完整同步流程"""
        # 初始化仓库
        if not self.init_repo():
            return False, "Failed to initialize git repository"
        
        # 添加文件
        if files:
            if not self.add_files(files):
                return False, "Failed to add files"
        else:
            if not self.add_all():
                return False, "Failed to add files"
        
        # 提交
        if not self.commit(content_title=content_title):
            if not self.has_changes():
                return True, "No changes to commit"
            return False, "Failed to commit"
        
        # 推送
        if self.git_url and not self.push():
            return False, "Failed to push"
        
        return True, "Sync completed successfully"
    
    def get_status(self) -> dict:
        """获取仓库状态"""
        status = {
            'is_repo': self.is_git_repo(),
            'has_changes': False,
            'branch': '',
            'remote': ''
        }
        
        if not status['is_repo']:
            return status
        
        status['has_changes'] = self.has_changes()
        
        _, stdout, _ = self._run_git(['branch', '--show-current'])
        status['branch'] = stdout.strip()
        
        _, stdout, _ = self._run_git(['remote', 'get-url', 'origin'])
        url = stdout.strip()
        # 隐藏token
        if '@' in url:
            url = 'https://' + url.split('@', 1)[1]
        status['remote'] = url
        
        return status