musicutil/src/utils/formats/generic_ffmpeg.rs

use std::{path::{PathBuf, Path}, process::Command};

use serde::Deserialize;
use string_error::static_err;

use crate::types::{AudioFileInfo, ReplayGainData, ReplayGainRawData, Tags};

use super::{AudioContainer, AudioContainerFormat, AudioFormatError, BoxedError};

#[derive(Default)]
struct Changes {
    title: Option<String>,
    artist: Option<String>,
    replaygain_data: Option<ReplayGainRawData>,
}

#[derive(Default)]
struct ExtractedData {
    tags: Tags,
    replaygain_data: Option<ReplayGainData>,
}

#[derive(Debug, Clone, Deserialize)]
struct FFProbeOutput {
    pub format: FFProbeFormat,
}

#[derive(Debug, Clone, Deserialize)]
struct FFProbeFormat {
    pub tags: FFProbeTags,
}

#[derive(Debug, Clone, Deserialize)]
struct FFProbeTags {
    #[serde(alias = "TITLE")]
    pub title: String,
    #[serde(default, alias = "ARTIST")]
    pub artist: String,

    #[serde(default, alias = "REPLAYGAIN_TRACK_PEAK")]
    pub replaygain_track_peak: Option<String>,
    #[serde(default, alias = "REPLAYGAIN_TRACK_GAIN")]
    pub replaygain_track_gain: Option<String>,
}

impl Default for FFProbeTags {
    fn default() -> Self {
        FFProbeTags {
            title: "".to_string(),
            artist: "".to_string(),
            replaygain_track_peak: None,
            replaygain_track_gain: None,
        }
    }
}

pub struct GenericFFMpegAudioFormat {
    container_type: AudioContainer,
    path: Box<PathBuf>,

    extracted_data: ExtractedData,
    changes: Changes,
}

impl GenericFFMpegAudioFormat {
    fn analyze(&mut self) -> Result<(), BoxedError> {
        let output = Command::new(crate::meta::FFPROBE)
            .args([
                "-v",
                "quiet",
                "-print_format",
                "json",
                "-show_format",
                &self.path.to_string_lossy(),
            ])
            .output()?;

        if !output.status.success() {
            print!("{:?}", String::from_utf8(output.stderr).unwrap());
            return Err(static_err("FFprobe Crashed"));
        }

        let output_str = String::from_utf8(output.stdout).unwrap();
        let ffprobe_out: FFProbeOutput = serde_json::from_str(output_str.as_str())?;

        let tags = ffprobe_out.format.tags;

        self.extracted_data.tags = Tags {
            title: tags.title,
            artist: tags.artist,
        };

        if tags.replaygain_track_gain.is_some() && tags.replaygain_track_peak.is_some() {
            self.extracted_data.replaygain_data = Some(ReplayGainData {
                track_gain: tags.replaygain_track_gain.unwrap(),
                track_peak: tags.replaygain_track_peak.unwrap(),
            });
        } else {
            self.extracted_data.replaygain_data = None;
        }

        Ok(())
    }
}

impl AudioContainerFormat for GenericFFMpegAudioFormat {
    fn get_tags(&self, allow_missing: bool) -> Result<Tags, BoxedError> {
        let mut tags = self.extracted_data.tags.clone();

        if let Some(title) = &self.changes.title {
            tags.title = title.clone();
        }

        if let Some(artist) = &self.changes.title {
            tags.artist = artist.clone();
        }

        if !allow_missing {
            if tags.title.is_empty() {
                return Err(Box::new(AudioFormatError::MissingTitle));
            }
            if tags.artist.is_empty() {
                return Err(Box::new(AudioFormatError::MissingArtist));
            }
        }

        Ok(tags)
    }

    fn get_replaygain_data(&self) -> Option<ReplayGainData> {
        if let Some(data) = &self.changes.replaygain_data {
            return Some(data.to_normal());
        }

        self.extracted_data.replaygain_data.clone()
    }

    fn supports_replaygain(&self) -> bool {
        match self.container_type {
            AudioContainer::MP3 => true,
            AudioContainer::FLAC => true,
            AudioContainer::WAV => true,
            AudioContainer::OGG => false, // ffprobe can't do OGG tags
            AudioContainer::AIFF => true,
            AudioContainer::Unknown => false,
        }
    }

    fn set_title(&mut self, title: String) -> Result<(), BoxedError> {
        self.changes.title = Some(title);
        Ok(())
    }

    fn set_artist(&mut self, artist: String) -> Result<(), BoxedError> {
        self.changes.artist = Some(artist);
        Ok(())
    }

    fn set_replaygain_data(&mut self, data: ReplayGainRawData) -> Result<(), BoxedError> {
        self.changes.replaygain_data = Some(data);
        Ok(())
    }

    fn save_changes(&mut self) -> Result<(), BoxedError> {
        let mut args: Vec<String> = Vec::new();

        let tempdir = tempfile::tempdir()?;
        let temp_file = tempdir
            .path()
            .join(PathBuf::from(self.path.file_name().unwrap()));

        args.extend(vec![
            "-i".to_string(),
            self.path.to_string_lossy().to_string(),
        ]);

        args.extend(vec!["-c".to_string(), "copy".to_string()]);

        if let Some(title) = self.changes.title.clone() {
            args.extend(vec![
                "-metadata".to_string(),
                format!("title=\"{}\"", title),
            ])
        }

        if let Some(artist) = self.changes.artist.clone() {
            args.extend(vec!["-metadata".to_string(), format!("artist={}", artist)])
        }

        args.push(temp_file.to_string_lossy().to_string());

        let output = Command::new(crate::meta::FFMPEG).args(args).output()?;

        println!("{:?}", String::from_utf8(output.stderr));

        std::fs::copy(temp_file, self.path.to_path_buf())?;

        Ok(())
    }

    fn get_audio_file_info(&self, allow_missing_tags: bool) -> Result<AudioFileInfo, BoxedError> {
        return Ok(AudioFileInfo {
            tags: self.get_tags(allow_missing_tags)?,
            replaygain: self.get_replaygain_data(),
            supports_replaygain: self.supports_replaygain(),
            container: self.container_type,
        });
    }
}

pub fn new_generic_ffmpeg_format_handler(
    path: &Path,
    container_type: AudioContainer,
) -> Result<GenericFFMpegAudioFormat, BoxedError> {
    let mut handler = GenericFFMpegAudioFormat {
        container_type,
        path: Box::new(path.to_path_buf()),
        extracted_data: ExtractedData::default(),
        changes: Changes::default(),
    };
    handler.analyze()?;

    Ok(handler)
}