package utils

import (
	"path/filepath"
	"time"

	logger "git.site.quack-lab.dev/dave/cylogger"
	"gorm.io/driver/sqlite"
	"gorm.io/gorm"
	gormlogger "gorm.io/gorm/logger"
)

// dbLogger is a scoped logger for the utils/db package.
var dbLogger = logger.Default.WithPrefix("utils/db")

type DB interface {
	DB() *gorm.DB
	Raw(sql string, args ...any) *gorm.DB
	SaveFile(filePath string, fileData []byte) error
	GetFile(filePath string) ([]byte, error)
	GetAllFiles() ([]FileSnapshot, error)
	RemoveAllFiles() error
}

type FileSnapshot struct {
	Date     time.Time `gorm:"primaryKey"`
	FilePath string    `gorm:"primaryKey"`
	FileData []byte    `gorm:"type:blob"`
}

type DBWrapper struct {
	db *gorm.DB
}

var globalDB *DBWrapper

func GetDB() (DB, error) {
	getDBLogger := dbLogger.WithPrefix("GetDB")
	getDBLogger.Debug("Attempting to get database connection")
	var err error

	dbFile := filepath.Join("data.sqlite")
	getDBLogger.Debug("Opening database file: %q", dbFile)
	db, err := gorm.Open(sqlite.Open(dbFile), &gorm.Config{
		// SkipDefaultTransaction: true,
		PrepareStmt: true,
		Logger:      gormlogger.Default.LogMode(gormlogger.Silent),
	})
	if err != nil {
		getDBLogger.Error("Failed to open database: %v", err)
		return nil, err
	}
	getDBLogger.Debug("Database opened successfully, running auto migration")
	if err := db.AutoMigrate(&FileSnapshot{}); err != nil {
		getDBLogger.Error("Auto migration failed: %v", err)
		return nil, err
	}
	getDBLogger.Debug("Auto migration completed")

	globalDB = &DBWrapper{db: db}
	getDBLogger.Debug("Database wrapper initialized")
	return globalDB, nil
}

// Just a wrapper
func (db *DBWrapper) Raw(sql string, args ...any) *gorm.DB {
	rawLogger := dbLogger.WithPrefix("Raw").WithField("sql", sql)
	rawLogger.Debug("Executing raw SQL query with args: %v", args)
	return db.db.Raw(sql, args...)
}

func (db *DBWrapper) DB() *gorm.DB {
	dbLogger.WithPrefix("DB").Debug("Returning GORM DB instance")
	return db.db
}

func (db *DBWrapper) FileExists(filePath string) (bool, error) {
	fileExistsLogger := dbLogger.WithPrefix("FileExists").WithField("filePath", filePath)
	fileExistsLogger.Debug("Checking if file exists in database")
	var count int64
	err := db.db.Model(&FileSnapshot{}).Where("file_path = ?", filePath).Count(&count).Error
	if err != nil {
		fileExistsLogger.Error("Error checking if file exists: %v", err)
		return false, err
	}
	fileExistsLogger.Debug("File exists: %t", count > 0)
	return count > 0, err
}

func (db *DBWrapper) SaveFile(filePath string, fileData []byte) error {
	saveFileLogger := dbLogger.WithPrefix("SaveFile").WithField("filePath", filePath)
	saveFileLogger.Debug("Attempting to save file to database")
	saveFileLogger.Trace("File data length: %d", len(fileData))

	exists, err := db.FileExists(filePath)
	if err != nil {
		saveFileLogger.Error("Error checking if file exists: %v", err)
		return err
	}
	if exists {
		saveFileLogger.Debug("File already exists, skipping save")
		return nil
	}
	saveFileLogger.Debug("Creating new file snapshot in database")
	err = db.db.Create(&FileSnapshot{
		Date:     time.Now(),
		FilePath: filePath,
		FileData: fileData,
	}).Error
	if err != nil {
		saveFileLogger.Error("Failed to create file snapshot: %v", err)
	} else {
		saveFileLogger.Debug("File saved successfully to database")
	}
	return err
}

func (db *DBWrapper) GetFile(filePath string) ([]byte, error) {
	getFileLogger := dbLogger.WithPrefix("GetFile").WithField("filePath", filePath)
	getFileLogger.Debug("Getting file from database")
	var fileSnapshot FileSnapshot
	err := db.db.Model(&FileSnapshot{}).Where("file_path = ?", filePath).First(&fileSnapshot).Error
	if err != nil {
		// Downgrade not-found to warning to avoid noisy errors during first run
		getFileLogger.Warning("Failed to get file from database: %v", err)
		return nil, err
	}
	getFileLogger.Debug("File found in database")
	getFileLogger.Trace("Retrieved file data length: %d", len(fileSnapshot.FileData))
	return fileSnapshot.FileData, nil
}

func (db *DBWrapper) GetAllFiles() ([]FileSnapshot, error) {
	getAllFilesLogger := dbLogger.WithPrefix("GetAllFiles")
	getAllFilesLogger.Debug("Getting all files from database")
	var fileSnapshots []FileSnapshot
	err := db.db.Model(&FileSnapshot{}).Find(&fileSnapshots).Error
	if err != nil {
		getAllFilesLogger.Error("Failed to get all files from database: %v", err)
		return nil, err
	}
	getAllFilesLogger.Debug("Found %d files in database", len(fileSnapshots))
	getAllFilesLogger.Trace("File snapshots retrieved: %v", fileSnapshots)
	return fileSnapshots, nil
}

func (db *DBWrapper) RemoveAllFiles() error {
	removeAllFilesLogger := dbLogger.WithPrefix("RemoveAllFiles")
	removeAllFilesLogger.Debug("Removing all files from database")
	err := db.db.Exec("DELETE FROM file_snapshots").Error
	if err != nil {
		removeAllFilesLogger.Error("Failed to remove all files from database: %v", err)
	} else {
		removeAllFilesLogger.Debug("All files removed from database")
	}
	return err
}