/**
 * Git 服务 - 封装 Tauri Git 操作
 * 通过 invoke() 调用 Rust 层 git 命令
 */

import { invoke } from '@tauri-apps/api/core';

// ==================== 类型定义 ====================

export interface GitFileStatus {
 path: string;
 status: 'modified' | 'added' | 'deleted' | 'untracked';
 staged: boolean;
}

export interface GitStatus {
 branch: string;
 ahead: number;
 behind: number;
 files: GitFileStatus[];
}

export interface GitLogEntry {
 hash: string;
 short_hash: string;
 author: string;
 date: string;
 message: string;
}

export interface DiffLine {
 line: number;
 type: 'added' | 'modified' | 'deleted';
}

// 检测 Tauri 环境
function isTauriEnv(): boolean {
 return typeof window !== 'undefined' &&
 ('__TAURI__' in window || '__TAURI_INTERNALS__' in window);
}

// ==================== Mock 数据 ====================

const mockGitStatus: GitStatus = {
 branch: 'main',
 ahead: 0,
 behind: 0,
 files: [],
};

const mockLog: GitLogEntry[] = [
 {
 hash: 'abc1234567890def1234567890abc1234567890',
 short_hash: 'abc1234',
 author: 'Developer',
 date: '2025年01月01日 12:00:00 +0800',
 message: '初始提交',
 },
];

// ==================== Git 服务 ====================

export const gitService = {
 /**
 * 获取 Git 状态
 */
 async status(cwd: string): Promise<GitStatus> {
 if (!isTauriEnv()) {
 console.warn('[gitService] 非 Tauri 环境,返回 mock 数据');
 return { ...mockGitStatus };
 }

 try {
 const result = await invoke<GitStatus>('git_status', { cwd });
 return result;
 } catch (err) {
 console.error('[gitService] git_status 失败:', err);
 return { ...mockGitStatus, branch: '', files: [] };
 }
 },

 /**
 * 暂存文件
 */
 async add(cwd: string, paths: string[]): Promise<void> {
 if (!isTauriEnv()) {
 console.log('[gitService] mock add:', paths);
 return;
 }
 await invoke('git_add', { cwd, paths });
 },

 /**
 * 取消暂存文件
 */
 async reset(cwd: string, paths: string[]): Promise<void> {
 if (!isTauriEnv()) {
 console.log('[gitService] mock reset:', paths);
 return;
 }
 await invoke('git_reset', { cwd, paths });
 },

 /**
 * 提交更改
 */
 async commit(cwd: string, message: string): Promise<void> {
 if (!isTauriEnv()) {
 console.log('[gitService] mock commit:', message);
 return;
 }
 await invoke('git_commit', { cwd, message });
 },

 /**
 * 推送到远程
 */
 async push(cwd: string): Promise<void> {
 if (!isTauriEnv()) {
 console.log('[gitService] mock push');
 return;
 }
 await invoke('git_push', { cwd });
 },

 /**
 * 拉取远程
 */
 async pull(cwd: string): Promise<void> {
 if (!isTauriEnv()) {
 console.log('[gitService] mock pull');
 return;
 }
 await invoke('git_pull', { cwd });
 },

 /**
 * 获取提交历史
 */
 async log(cwd: string, count: number = 20): Promise<GitLogEntry[]> {
 if (!isTauriEnv()) {
 return [...mockLog];
 }

 try {
 return await invoke<GitLogEntry[]>('git_log', { cwd, count });
 } catch (err) {
 console.error('[gitService] git_log 失败:', err);
 return [];
 }
 },

 /**
 * 获取分支列表
 */
 async branches(cwd: string): Promise<string[]> {
 if (!isTauriEnv()) {
 return ['main'];
 }

 try {
 return await invoke<string[]>('git_branches', { cwd });
 } catch (err) {
 console.error('[gitService] git_branches 失败:', err);
 return [];
 }
 },

 /**
 * 切换分支
 */
 async checkout(cwd: string, branch: string): Promise<void> {
 if (!isTauriEnv()) {
 console.log('[gitService] mock checkout:', branch);
 return;
 }
 await invoke('git_checkout', { cwd, branch });
 },

 /**
 * 丢弃文件更改
 */
 async discard(cwd: string, paths: string[]): Promise<void> {
 if (!isTauriEnv()) {
 console.log('[gitService] mock discard:', paths);
 return;
 }
 await invoke('git_discard', { cwd, paths });
 },

 /**
 * 获取单个文件的 git diff(与 HEAD 比较)
 */
 async diffFile(cwd: string, filePath: string): Promise<DiffLine[]> {
 if (!isTauriEnv()) {
 console.log('[gitService] mock diffFile:', filePath);
 return [];
 }
 try {
 return await invoke<DiffLine[]>('git_diff_file', { cwd, filePath });
 } catch (err) {
 console.error('[gitService] git_diff_file 失败:', err);
 return [];
 }
 },

 /**
 * 获取文件在 HEAD 中的内容(原始版本)
 */
 async showHead(cwd: string, filePath: string): Promise<string> {
 if (!isTauriEnv()) return '';
 try {
 return await invoke<string>('git_show_head', { cwd, filePath });
 } catch (err) {
 console.warn('[gitService] git_show_head 失败:', err);
 return '';
 }
 },

 /**
 * 获取文件的完整 diff 文本
 */
 async diffText(cwd: string, filePath: string): Promise<string> {
 if (!isTauriEnv()) return '';
 try {
 return await invoke<string>('git_diff_text', { cwd, filePath });
 } catch (err) {
 console.warn('[gitService] git_diff_text 失败:', err);
 return '';
 }
 },

 /**
 * 获取所有已暂存文件的 diff 文本(用于 AI 生成 commit message)
 */
 async diffStaged(cwd: string): Promise<string> {
 if (!isTauriEnv()) return '';
 try {
 return await invoke<string>('git_diff_staged', { cwd });
 } catch (err) {
 console.warn('[gitService] git_diff_staged 失败:', err);
 return '';
 }
 },
};

export default gitService;