//! Subtitle management for video media items.

use std::path::PathBuf;

use chrono::{DateTime, Utc};
use serde::{Deserialize, Serialize};
use uuid::Uuid;

use crate::model::MediaId;

/// A subtitle track associated with a media item.
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct Subtitle {
  pub id:          Uuid,
  pub media_id:    MediaId,
  pub language:    Option<String>,
  pub format:      SubtitleFormat,
  pub file_path:   Option<PathBuf>,
  pub is_embedded: bool,
  pub track_index: Option<usize>,
  pub offset_ms:   i64,
  pub created_at:  DateTime<Utc>,
}

/// Supported subtitle formats.
#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize)]
#[serde(rename_all = "lowercase")]
pub enum SubtitleFormat {
  Srt,
  Vtt,
  Ass,
  Ssa,
  Pgs,
}

impl std::fmt::Display for SubtitleFormat {
  fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
    let s = match self {
      Self::Srt => "srt",
      Self::Vtt => "vtt",
      Self::Ass => "ass",
      Self::Ssa => "ssa",
      Self::Pgs => "pgs",
    };
    write!(f, "{s}")
  }
}

impl std::str::FromStr for SubtitleFormat {
  type Err = String;

  fn from_str(s: &str) -> std::result::Result<Self, Self::Err> {
    match s {
      "srt" => Ok(Self::Srt),
      "vtt" => Ok(Self::Vtt),
      "ass" => Ok(Self::Ass),
      "ssa" => Ok(Self::Ssa),
      "pgs" => Ok(Self::Pgs),
      _ => Err(format!("unknown subtitle format: {s}")),
    }
  }
}