package db

import (
	"database/sql"
	_ "embed"
	"fmt"

	_ "modernc.org/sqlite"

	"golang.org/x/crypto/bcrypt"
	"qbank/internal/config"
)

//go:embed schema.sql
var schema string

func Open(path string) (*sql.DB, error) {
	db, err := sql.Open("sqlite", path)
	if err != nil {
		return nil, fmt.Errorf("open sqlite: %w", err)
	}
	db.SetMaxOpenConns(1)
	for _, stmt := range []string{
		"PRAGMA journal_mode=WAL",
		"PRAGMA foreign_keys=ON",
	} {
		if _, err := db.Exec(stmt); err != nil {
			db.Close()
			return nil, fmt.Errorf("pragma %q: %w", stmt, err)
		}
	}
	if _, err := db.Exec(schema); err != nil {
		db.Close()
		return nil, fmt.Errorf("apply schema: %w", err)
	}
	return db, nil
}

func Seed(db *sql.DB, users []config.AdminUser) error {
	var count int
	if err := db.QueryRow("SELECT COUNT(*) FROM users").Scan(&count); err != nil {
		return fmt.Errorf("count users: %w", err)
	}
	if count > 0 {
		return nil
	}
	for _, u := range users {
		hash, err := bcrypt.GenerateFromPassword([]byte(u.Password), bcrypt.DefaultCost)
		if err != nil {
			return fmt.Errorf("hash password for %q: %w", u.Name, err)
		}
		if _, err := db.Exec("INSERT INTO users (name, password_hash) VALUES (?, ?)", u.Name, string(hash)); err != nil {
			return fmt.Errorf("insert user %q: %w", u.Name, err)
		}
	}
	return nil
}