Add RunConvert method to FFmpegContract and implementation

Extend `FFmpegContract` with `RunConvert` for handling file conversion, including progress tracking and callback support before and after execution.

internal/ffmpeg/ffmpeg.go

@@ -5,13 +5,20 @@ import (
 	"errors"
 	"fyne.io/fyne/v2/lang"
 	"git.kor-elf.net/kor-elf/gui-for-ffmpeg/internal/utils"
+	"io"
 	"os/exec"
 	"strings"
 )
 
+type ProgressContract interface {
+	GetProtocole() string
+	Run(stdOut io.ReadCloser, stdErr io.ReadCloser) error
+}
+
 type FFmpegContract interface {
 	GetPath() string
 	GetEncoders(scanner func(scanner *bufio.Reader)) error
+	RunConvert(setting ConvertSetting, progress ProgressContract, beforeWait func(cmd *exec.Cmd), afterWait func(cmd *exec.Cmd)) error
 }
 
 type ffmpeg struct {
@@ -40,6 +47,51 @@ func (f *ffmpeg) GetPath() string {
 	return f.path
 }
 
+func (f *ffmpeg) RunConvert(setting ConvertSetting, progress ProgressContract, beforeWait func(cmd *exec.Cmd), afterWait func(cmd *exec.Cmd)) error {
+	overwriteOutputFiles := "-n"
+	if setting.OverwriteOutputFiles == true {
+		overwriteOutputFiles = "-y"
+	}
+	args := []string{overwriteOutputFiles, "-i", setting.FileInput.Path}
+	args = append(args, setting.Encoder.GetParams()...)
+	args = append(args, "-progress", progress.GetProtocole(), setting.FileOut.Path)
+	cmd := exec.Command(f.path, args...)
+	utils.PrepareBackgroundCommand(cmd)
+
+	stdOut, err := cmd.StdoutPipe()
+	if err != nil {
+		return err
+	}
+	stdErr, err := cmd.StderrPipe()
+	if err != nil {
+		return err
+	}
+
+	err = cmd.Start()
+	if err != nil {
+		return err
+	}
+
+	if beforeWait != nil {
+		beforeWait(cmd)
+	}
+
+	errProgress := progress.Run(stdOut, stdErr)
+
+	err = cmd.Wait()
+	if afterWait != nil {
+		afterWait(cmd)
+	}
+	if errProgress != nil {
+		return errProgress
+	}
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
 func (f *ffmpeg) GetEncoders(scanner func(scanner *bufio.Reader)) error {
 	cmd := exec.Command(f.path, "-encoders")
 	utils.PrepareBackgroundCommand(cmd)