package db

import (
	"fmt"
	"log"
	"os"

	"gorm.io/driver/sqlite"
	"gorm.io/gorm"

	"git.artlef.fr/PersonalLibraryManager/internal/model"
)

func Initdb(databaseDir string, demoDataPath string) *gorm.DB {
	createDbFolderIfMissing(databaseDir)
	db, err := gorm.Open(
		sqlite.Open(
			fmt.Sprintf(
				"%s/plm.db", databaseDir)), &gorm.Config{})
	if err != nil {
		log.Fatal(err)
	}
	// Migrate the schema
	db.AutoMigrate(&model.Book{})
	var book model.Book
	queryResult := db.Limit(1).Find(&book)
	if queryResult.RowsAffected == 0 && demoDataPath != "" {
		migrateSchema(db, demoDataPath)
	}
	return db
}

func migrateSchema(db *gorm.DB, demoDataPath string) {
	log.Printf("Loading demo data file %s\n", demoDataPath)
	data, err := os.ReadFile(demoDataPath)
	if err != nil {
		log.Fatal(err)
	}
	db.Exec(string(data))
}

func createDbFolderIfMissing(databaseDir string) {
	_, openFileErr := os.Open(databaseDir)
	if os.IsNotExist(openFileErr) {
		createNonExistingDbFolder(databaseDir)
	} else if openFileErr != nil {
		log.Fatal(openFileErr)
	}
}

func createNonExistingDbFolder(databaseDir string) {
	log.Printf("Creating missing folder %s\n", databaseDir)
	err := os.MkdirAll(databaseDir, 0700)
	if err != nil {
		log.Fatal(err)
	}
}