package db

import (
	"base-framework/pkg/config"
	"base-framework/pkg/router"
	"database/sql"
	"errors"
	"fmt"
)

type Client struct {
	conn *sql.DB
	tx   *sql.Tx
}

// JdbcTemplate 创建 JdbcTemplate
func JdbcTemplate(c *router.Context) (*Client, error) {
	val, ok := c.Get("orgId")
	if !ok {
		return nil, errors.New("missing orgId in context")
	}
	orgId, ok := val.(string)
	if !ok || orgId == "" {
		return nil, errors.New("invalid orgId in context")
	}
	conn, ok := config.GetDB(orgId)
	if !ok || conn == nil {
		return nil, fmt.Errorf("no db connection found for orgId=%s", orgId)
	}
	return &Client{conn: conn}, nil
}

// ------------------------ 内部方法 ------------------------

// 执行查询，返回 *sql.Rows
func (c *Client) query(query string, args ...any) (*sql.Rows, error) {
	if c.tx != nil {
		return c.tx.Query(query, args...)
	}
	return c.conn.Query(query, args...)
}

// 执行执行类语句（insert/update/delete）
func (c *Client) exec(query string, args ...any) (sql.Result, error) {
	if c.tx != nil {
		return c.tx.Exec(query, args...)
	}
	return c.conn.Exec(query, args...)
}

// WithTransaction 自动处理事务提交或回滚
func (c *Client) WithTransaction(fn func(txClient *Client) error) error {
	if c.tx != nil {
		// 已经在事务中，直接执行
		return fn(c)
	}

	tx, err := c.conn.Begin()
	if err != nil {
		return err
	}
	txClient := &Client{conn: c.conn, tx: tx}
	if err := fn(txClient); err != nil {
		_ = tx.Rollback()
		return err
	}
	return tx.Commit()
}