package db

import (
	"database/sql"
	"os"
	"scrap/internal/config"
	"strings"

	_ "github.com/mattn/go-sqlite3"
)

var dbInstance *sql.DB

func Setup() {
	db, err := sql.Open("sqlite3", "./example.db")
	if err != nil {
		panic(err)
	}

	dbInstance = db

	tableFilenames := getTableFilenames()
	createTablesFromSQLFiles(tableFilenames)
}

func GetInstance() *sql.DB { return dbInstance }

func Close() { dbInstance.Close() }

func getTableFilenames() []string {
	appConfig := config.GetAppConfig()

	files, err := os.ReadDir(appConfig.SqlTablesDir)
	if err != nil {
		panic(err)
	}

	filenames := []string{}
	for _, f := range files {
		fName := f.Name()
		if !strings.HasSuffix(fName, ".sql") {
			continue
		}

		filenames = append(filenames, fName)
	}

	return filenames
}

func createTablesFromSQLFiles(filenames []string) {
	appConfig := config.GetAppConfig()

	for _, fName := range filenames {
		tableBytes, err := os.ReadFile(appConfig.SqlTablesDir + fName)
		if err != nil {
			panic(err)
		}

		tableQuery := string(tableBytes)
		if _, err = dbInstance.Exec(tableQuery); err != nil {
			panic(err)
		}
	}
}