feat: argparse and dry-run.

src/video_merger.rs

@@ -0,0 +1,49 @@
+use crate::dry_run::ShellScript;
+use crate::ffmpeg::FFmpegCommand;
+use std::io::Result;
+use std::path::{Path, PathBuf};
+use std::fs;
+
+pub fn merge_video_and_audio(video_path: &Path, audio_path: &Path, dry_run: bool, overwrite: bool) -> Result<PathBuf> {
+    let origin_video_extension = video_path.extension().unwrap().to_str().unwrap();
+    let origin_filename = format!("original.{}", &origin_video_extension);
+    let origin_path = video_path.parent().unwrap().join(origin_filename);
+    let output_path = video_path.with_extension("mp4");
+
+    if dry_run {
+        let mut script = ShellScript::new();
+        script.add_comment("Rename original video file");
+        script.add_variable("VIDEO_BACKUP", &origin_path);
+        script.add_variable("VIDEO_OUTPUT", &output_path);
+        script.add_command("mv \"$VIDEO_FILE\" \"$VIDEO_BACKUP\"");
+        script.add_empty_line();
+        script.add_comment("Merge video and audio");
+        crate::dry_run::print_shell_script(&script);
+        FFmpegCommand::new()
+            .overwrite(overwrite)
+            .input_var("VIDEO_BACKUP")
+            .input_var("AUDIO_AAC")
+            .codec("copy")
+            .output_var("VIDEO_OUTPUT")
+            .execute(true)?;
+        return Ok(output_path);
+    }
+
+    println!("Renaming original video: {} -> {}", video_path.display(), origin_path.display());
+    fs::rename(video_path, &origin_path)?;
+
+    println!("Merging video and audio:");
+    println!("  Video: {}", origin_path.display());
+    println!("  Audio: {}", audio_path.display());
+    println!("  Output: {}", output_path.display());
+    FFmpegCommand::new()
+        .overwrite(overwrite)
+        .input(&origin_path)
+        .input(audio_path)
+        .codec("copy")
+        .output(&output_path)
+        .execute(false)?;
+
+    println!("Merge completed: {}", output_path.display());
+    Ok(output_path)
+}