package database

import (
	"database/sql"
	"fmt"
	"os"
	"path/filepath"

	_ "modernc.org/sqlite"
)

// DB 数据库实例
type DB struct {
	*sql.DB
}

// InitDB 初始化数据库
func InitDB(dbPath string) (*DB, error) {
	// 确保数据库目录存在
	dbDir := filepath.Dir(dbPath)
	if err := os.MkdirAll(dbDir, 0755); err != nil {
		return nil, fmt.Errorf("创建数据库目录失败: %v", err)
	}

	// 打开数据库连接（使用modernc.org/sqlite驱动）
	db, err := sql.Open("sqlite", dbPath)
	if err != nil {
		return nil, fmt.Errorf("打开数据库失败: %v", err)
	}

	// 测试连接
	if err := db.Ping(); err != nil {
		return nil, fmt.Errorf("数据库连接测试失败: %v", err)
	}

	// 创建表
	if err := createTables(db); err != nil {
		return nil, fmt.Errorf("创建数据表失败: %v", err)
	}

	fmt.Println("✅ 数据库初始化成功:", dbPath)
	return &DB{db}, nil
}

// createTables 创建数据表
func createTables(db *sql.DB) error {
	// 公众号表
	officialAccountTable := `
	CREATE TABLE IF NOT EXISTS official_accounts (
		id INTEGER PRIMARY KEY AUTOINCREMENT,
		biz TEXT NOT NULL UNIQUE,
		nickname TEXT NOT NULL,
		homepage TEXT,
		description TEXT,
		created_at DATETIME DEFAULT CURRENT_TIMESTAMP,
		updated_at DATETIME DEFAULT CURRENT_TIMESTAMP
	);
	CREATE INDEX IF NOT EXISTS idx_biz ON official_accounts(biz);
	CREATE INDEX IF NOT EXISTS idx_nickname ON official_accounts(nickname);
	`

	// 文章表
	articleTable := `
	CREATE TABLE IF NOT EXISTS articles (
		id INTEGER PRIMARY KEY AUTOINCREMENT,
		official_id INTEGER NOT NULL,
		title TEXT NOT NULL,
		author TEXT,
		link TEXT UNIQUE,
		publish_time TEXT,
		create_time TEXT,
		comment_id TEXT,
		read_num INTEGER DEFAULT 0,
		like_num INTEGER DEFAULT 0,
		share_num INTEGER DEFAULT 0,
		content_preview TEXT,
		paragraph_count INTEGER DEFAULT 0,
		created_at DATETIME DEFAULT CURRENT_TIMESTAMP,
		updated_at DATETIME DEFAULT CURRENT_TIMESTAMP,
		FOREIGN KEY (official_id) REFERENCES official_accounts(id)
	);
	CREATE INDEX IF NOT EXISTS idx_official_id ON articles(official_id);
	CREATE INDEX IF NOT EXISTS idx_title ON articles(title);
	CREATE INDEX IF NOT EXISTS idx_publish_time ON articles(publish_time);
	CREATE INDEX IF NOT EXISTS idx_link ON articles(link);
	`

	// 文章内容表
	articleContentTable := `
	CREATE TABLE IF NOT EXISTS article_contents (
		id INTEGER PRIMARY KEY AUTOINCREMENT,
		article_id INTEGER NOT NULL UNIQUE,
		html_content TEXT,
		text_content TEXT,
		paragraphs TEXT,
		images TEXT,
		created_at DATETIME DEFAULT CURRENT_TIMESTAMP,
		FOREIGN KEY (article_id) REFERENCES articles(id) ON DELETE CASCADE
	);
	CREATE INDEX IF NOT EXISTS idx_article_id ON article_contents(article_id);
	`

	// 执行创建表语句
	tables := []string{officialAccountTable, articleTable, articleContentTable}
	for _, table := range tables {
		if _, err := db.Exec(table); err != nil {
			return err
		}
	}

	return nil
}

// Close 关闭数据库连接
func (db *DB) Close() error {
	return db.DB.Close()
}