// Package pkg /
/*****
@author    Jonas Kaninda
@license   MIT License <https://opensource.org/licenses/MIT>
@Copyright © 2024 Jonas Kaninda
**/
package pkg

import (
	"fmt"
	"github.com/hpcloud/tail"
	"github.com/jkaninda/mysql-bkup/utils"
	"github.com/spf13/cobra"
	"log"
	"os"
	"os/exec"
	"path/filepath"
	"time"
)

func StartBackup(cmd *cobra.Command) {
	intro()
	//Set env
	utils.SetEnv("STORAGE_PATH", storagePath)
	utils.GetEnv(cmd, "period", "BACKUP_CRON_EXPRESSION")

	//Get flag value and set env
	remotePath := utils.GetEnv(cmd, "path", "SSH_REMOTE_PATH")
	storage = utils.GetEnv(cmd, "storage", "STORAGE")
	file = utils.GetEnv(cmd, "file", "FILE_NAME")
	backupRetention, _ := cmd.Flags().GetInt("keep-last")
	prune, _ := cmd.Flags().GetBool("prune")
	disableCompression, _ = cmd.Flags().GetBool("disable-compression")
	executionMode, _ = cmd.Flags().GetString("mode")
	gpqPassphrase := os.Getenv("GPG_PASSPHRASE")
	_ = utils.GetEnv(cmd, "path", "AWS_S3_PATH")

	dbConf = getDbConfig(cmd)

	//
	if gpqPassphrase != "" {
		encryption = true
	}

	//Generate file name
	backupFileName := fmt.Sprintf("%s_%s.sql.gz", dbConf.dbName, time.Now().Format("20060102_150405"))
	if disableCompression {
		backupFileName = fmt.Sprintf("%s_%s.sql", dbConf.dbName, time.Now().Format("20060102_150405"))
	}

	if executionMode == "default" {
		switch storage {
		case "s3":
			s3Backup(dbConf, backupFileName, disableCompression, prune, backupRetention, encryption)
		case "local":
			localBackup(dbConf, backupFileName, disableCompression, prune, backupRetention, encryption)
		case "ssh", "remote":
			sshBackup(dbConf, backupFileName, remotePath, disableCompression, prune, backupRetention, encryption)
		case "ftp":
			utils.Fatal("Not supported storage type: %s", storage)
		default:
			localBackup(dbConf, backupFileName, disableCompression, prune, backupRetention, encryption)
		}

	} else if executionMode == "scheduled" {
		scheduledMode(dbConf, storage)
	} else {
		utils.Fatal("Error, unknown execution mode!")
	}

}

// Run in scheduled mode
func scheduledMode(db *dbConfig, storage string) {

	fmt.Println()
	fmt.Println("**********************************")
	fmt.Println("     Starting MySQL Bkup...       ")
	fmt.Println("***********************************")
	utils.Info("Running in Scheduled mode")
	utils.Info("Execution period  %s", os.Getenv("BACKUP_CRON_EXPRESSION"))
	utils.Info("Storage type %s ", storage)

	//Test database connexion
	testDatabaseConnection(db)

	utils.Info("Creating backup job...")
	CreateCrontabScript(disableCompression, storage)

	supervisorConfig := "/etc/supervisor/supervisord.conf"

	// Start Supervisor
	cmd := exec.Command("supervisord", "-c", supervisorConfig)
	err := cmd.Start()
	if err != nil {
		utils.Fatal(fmt.Sprintf("Failed to start supervisord: %v", err))
	}
	utils.Info("Backup job started")
	defer func() {
		if err := cmd.Process.Kill(); err != nil {
			utils.Info("Failed to kill supervisord process: %v", err)
		} else {
			utils.Info("Supervisor stopped.")
		}
	}()
	if _, err := os.Stat(cronLogFile); os.IsNotExist(err) {
		utils.Fatal(fmt.Sprintf("Log file %s does not exist.", cronLogFile))
	}
	t, err := tail.TailFile(cronLogFile, tail.Config{Follow: true})
	if err != nil {
		utils.Fatal("Failed to tail file: %v", err)
	}

	// Read and print new lines from the log file
	for line := range t.Lines {
		fmt.Println(line.Text)
	}
}
func intro() {
	fmt.Println()
	fmt.Println("**********************************")
	fmt.Println("            MySQL Backup          ")
	fmt.Println("     @Copyright © 2024 jkaninda    ")
	fmt.Println("***********************************")
}

// BackupDatabase backup database
func BackupDatabase(db *dbConfig, backupFileName string, disableCompression bool) {
	storagePath = os.Getenv("STORAGE_PATH")

	err := utils.CheckEnvVars(dbHVars)
	if err != nil {
		utils.Error("Please make sure all required environment variables for database are set")
		utils.Fatal("Error checking environment variables: %s", err)
	}

	utils.Info("Starting database backup...")
	testDatabaseConnection(db)

	// Backup Database database
	utils.Info("Backing up database...")

	if disableCompression {
		// Execute mysqldump
		cmd := exec.Command("mysqldump",
			"-h", db.dbHost,
			"-P", db.dbPort,
			"-u", db.dbUserName,
			"--password="+db.dbPassword,
			db.dbName,
		)
		output, err := cmd.Output()
		if err != nil {
			log.Fatal(err)
		}

		// save output
		file, err := os.Create(fmt.Sprintf("%s/%s", tmpPath, backupFileName))
		if err != nil {
			log.Fatal(err)
		}
		defer file.Close()

		_, err = file.Write(output)
		if err != nil {
			log.Fatal(err)
		}
		utils.Done("Database has been backed up")

	} else {
		// Execute mysqldump
		cmd := exec.Command("mysqldump", "-h", db.dbHost, "-P", db.dbPort, "-u", db.dbUserName, "--password="+db.dbPassword, db.dbName)
		stdout, err := cmd.StdoutPipe()
		if err != nil {
			log.Fatal(err)
		}
		gzipCmd := exec.Command("gzip")
		gzipCmd.Stdin = stdout
		gzipCmd.Stdout, err = os.Create(fmt.Sprintf("%s/%s", tmpPath, backupFileName))
		gzipCmd.Start()
		if err != nil {
			log.Fatal(err)
		}
		if err := cmd.Run(); err != nil {
			log.Fatal(err)
		}
		if err := gzipCmd.Wait(); err != nil {
			log.Fatal(err)
		}
		utils.Done("Database has been backed up")

	}

}
func localBackup(db *dbConfig, backupFileName string, disableCompression bool, prune bool, backupRetention int, encrypt bool) {
	utils.Info("Backup database to local storage")
	BackupDatabase(db, backupFileName, disableCompression)
	finalFileName := backupFileName
	if encrypt {
		encryptBackup(backupFileName)
		finalFileName = fmt.Sprintf("%s.%s", backupFileName, gpgExtension)
	}
	utils.Info("Backup name is %s", finalFileName)
	moveToBackup(finalFileName, storagePath)
	//Send notification
	utils.NotifySuccess(finalFileName)
	//Delete old backup
	if prune {
		deleteOldBackup(backupRetention)
	}
	//Delete temp
	deleteTemp()
}

func s3Backup(db *dbConfig, backupFileName string, disableCompression bool, prune bool, backupRetention int, encrypt bool) {
	bucket := utils.GetEnvVariable("AWS_S3_BUCKET_NAME", "BUCKET_NAME")
	s3Path := utils.GetEnvVariable("AWS_S3_PATH", "S3_PATH")
	utils.Info("Backup database to s3 storage")
	//Backup database
	BackupDatabase(db, backupFileName, disableCompression)
	finalFileName := backupFileName
	if encrypt {
		encryptBackup(backupFileName)
		finalFileName = fmt.Sprintf("%s.%s", backupFileName, "gpg")
	}
	utils.Info("Uploading backup archive to remote storage S3 ... ")
	utils.Info("Backup name is %s", finalFileName)
	err := utils.UploadFileToS3(tmpPath, finalFileName, bucket, s3Path)
	if err != nil {
		utils.Fatal("Error uploading file to S3: %s ", err)

	}

	//Delete backup file from tmp folder
	err = utils.DeleteFile(filepath.Join(tmpPath, backupFileName))
	if err != nil {
		fmt.Println("Error deleting file: ", err)

	}
	// Delete old backup
	if prune {
		err := utils.DeleteOldBackup(bucket, s3Path, backupRetention)
		if err != nil {
			utils.Fatal("Error deleting old backup from S3: %s ", err)
		}
	}
	utils.Done("Uploading backup archive to remote storage S3 ... done ")
	//Send notification
	utils.NotifySuccess(finalFileName)
	//Delete temp
	deleteTemp()
}
func sshBackup(db *dbConfig, backupFileName, remotePath string, disableCompression bool, prune bool, backupRetention int, encrypt bool) {
	utils.Info("Backup database to Remote server")
	//Backup database
	BackupDatabase(db, backupFileName, disableCompression)
	finalFileName := backupFileName
	if encrypt {
		encryptBackup(backupFileName)
		finalFileName = fmt.Sprintf("%s.%s", backupFileName, "gpg")
	}
	utils.Info("Uploading backup archive to remote storage ... ")
	utils.Info("Backup name is %s", finalFileName)
	err := CopyToRemote(finalFileName, remotePath)
	if err != nil {
		utils.Fatal("Error uploading file to the remote server: %s ", err)

	}

	//Delete backup file from tmp folder
	err = utils.DeleteFile(filepath.Join(tmpPath, finalFileName))
	if err != nil {
		fmt.Println("Error deleting file: ", err)

	}
	if prune {
		//TODO: Delete old backup from remote server
		utils.Info("Deleting old backup from a remote server is not implemented yet")

	}

	utils.Done("Uploading backup archive to remote storage ... done ")
	//Send notification
	utils.NotifySuccess(finalFileName)
	//Delete temp
	deleteTemp()
}
func encryptBackup(backupFileName string) {
	gpgPassphrase := os.Getenv("GPG_PASSPHRASE")
	err := Encrypt(filepath.Join(tmpPath, backupFileName), gpgPassphrase)
	if err != nil {
		utils.Fatal("Error during encrypting backup %s", err)
	}

}