package task

import (
	"bufio"
	"bytes"
	"context"
	"os/exec"
	"sync"

	"git.lastassault.de/speatzle/morffix/config"
	"git.lastassault.de/speatzle/morffix/constants"
	"git.lastassault.de/speatzle/morffix/task/log"
	"git.lastassault.de/speatzle/morffix/types"
)

// dropCR drops a terminal \r from the data.
func dropCR(data []byte) []byte {
	if len(data) > 0 && data[len(data)-1] == '\r' {
		return data[0 : len(data)-1]
	}
	return data
}

func scanLines(data []byte, atEOF bool) (advance int, token []byte, err error) {
	if atEOF && len(data) == 0 {
		return 0, nil, nil
	}
	if i := bytes.IndexByte(data, '\n'); i >= 0 {
		// We have a full newline-terminated line.
		return i + 1, dropCR(data[0:i]), nil
	}
	if i := bytes.IndexByte(data, '\r'); i >= 0 {
		// We have a return line.
		return i + 1, dropCR(data[0:i]), nil
	}
	// If we're at EOF, we have a final, non-terminated line. Return it.
	if atEOF {
		return len(data), dropCR(data), nil
	}
	// Request more data.
	return 0, nil, nil
}

func RunHealthCheck(conf config.Config, t *types.Task, data types.HealthCheckData) {
	ctx := context.TODO()
	l := log.GetTaskLogger(t)
	l.InfoContext(ctx, "Running ffmpeg", "args", data.Command.GetArgs())
	path := conf.Worker.FFmpegPath
	if path == "" {
		path = "ffmpeg"
	}
	cmd := exec.CommandContext(ctx, path, data.Command.GetArgs()...)

	var wg sync.WaitGroup

	stdout, err := cmd.StdoutPipe()
	if err != nil {
		l.ErrorContext(ctx, "Error getting StdoutPipe", "err", err)
		return
	}

	wg.Add(1)
	outScanner := bufio.NewScanner(stdout)
	outScanner.Split(scanLines)
	go func() {
		for outScanner.Scan() {
			l.InfoContext(ctx, outScanner.Text())
		}
		wg.Done()
	}()

	stderr, err := cmd.StderrPipe()
	if err != nil {
		l.ErrorContext(ctx, "Error getting StderrPipe", "err", err)
		return
	}
	wg.Add(1)
	errScanner := bufio.NewScanner(stderr)
	errScanner.Split(scanLines)
	go func() {
		for errScanner.Scan() {
			l.InfoContext(ctx, errScanner.Text())
		}
		wg.Done()
	}()

	err = cmd.Start()
	if err != nil {
		l.ErrorContext(ctx, "Error Starting ffmpeg", "err", err)
		return
	}

	wg.Wait()

	err = cmd.Wait()
	if err != nil {
		l.ErrorContext(ctx, "Error Running ffmpeg", "err", err)
		return
	}

	l.InfoContext(ctx, "Task Success")
	t.Status = constants.TASK_STATUS_SUCCESS
}