use std::fs;

use tauri::{AppHandle, State};

use crate::config;
use crate::ffmpeg::{commands, probe, runner};
use crate::recovery;
use crate::types::*;
use crate::AppState;

#[tauri::command]
pub async fn compress(
    input: String,
    output: String,
    settings: CompressSettings,
    trim: Option<TrimRange>,
    app: AppHandle,
    state: State<'_, AppState>,
) -> Result<OutputInfo, String> {
    let ffmpeg_path = {
        let cfg = state.config.lock().map_err(|e| e.to_string())?;
        cfg.ffmpeg_path.clone()
    };
    let ffmpeg = ffmpeg_path.unwrap_or_else(|| "ffmpeg".into());

    let app_config = {
        let cfg = state.config.lock().map_err(|e| e.to_string())?;
        cfg.clone()
    };

    let hw_info = {
        let hw = state.hw_info.lock().map_err(|e| e.to_string())?;
        hw.clone().unwrap_or(HardwareInfo {
            nvenc: false,
            qsv: false,
            amf: false,
            nvenc_codecs: Vec::new(),
            qsv_codecs: Vec::new(),
            amf_codecs: Vec::new(),
        })
    };

    let job_id = uuid::Uuid::new_v4().to_string();
    let jobs = state.jobs.clone();

    let info = {
        let input = input.clone();
        let ffmpeg = ffmpeg.clone();
        tokio::task::spawn_blocking(move || probe::probe_video(&input, &ffmpeg))
            .await
            .map_err(|e| e.to_string())??
    };

    let duration = match &trim {
        Some(t) => t.end - t.start,
        None => info.duration,
    };

    let has_audio = info.audio_codec.is_some();

    let settings_json = serde_json::to_string(&settings).unwrap_or_default();
    recovery::write_job_info(&config::temp_dir(), &input, &output, "compress", &settings_json);

    let (out_path, attempts) = {
        let input = input.clone();
        let output = output.clone();
        let settings = settings.clone();
        let trim = trim.clone();
        let ffmpeg = ffmpeg.clone();
        let hw = hw_info.clone();
        let cfg = app_config.clone();
        let jid = job_id.clone();
        let app = app.clone();
        let jobs = jobs.clone();

        tokio::task::spawn_blocking(move || {
            runner::run_compress_with_retry(
                &ffmpeg,
                &input,
                &output,
                &settings,
                trim.as_ref(),
                &hw,
                &cfg,
                &jid,
                duration,
                has_audio,
                &app,
                &jobs,
            )
        })
        .await
        .map_err(|e| e.to_string())??
    };

    recovery::delete_job_info(&config::temp_dir());

    let out_info = {
        let path = out_path.clone();
        let ffmpeg = ffmpeg.clone();
        tokio::task::spawn_blocking(move || probe::probe_video(&path, &ffmpeg))
            .await
            .map_err(|e| e.to_string())??
    };

    let file_size = fs::metadata(&out_path).map(|m| m.len()).unwrap_or(0);

    Ok(OutputInfo {
        path: out_path,
        file_size,
        duration: out_info.duration,
        width: out_info.width,
        height: out_info.height,
        video_codec: out_info.video_codec,
        video_bitrate: out_info.video_bitrate,
        audio_codec: out_info.audio_codec,
        audio_bitrate: out_info.audio_bitrate,
        attempts,
    })
}

#[tauri::command]
pub async fn trim(
    input: String,
    output: String,
    range: TrimRange,
    smart_cut: bool,
    strip_audio: Option<bool>,
    app: AppHandle,
    state: State<'_, AppState>,
) -> Result<OutputInfo, String> {
    let ffmpeg_path = {
        let cfg = state.config.lock().map_err(|e| e.to_string())?;
        cfg.ffmpeg_path.clone()
    };
    let ffmpeg = ffmpeg_path.unwrap_or_else(|| "ffmpeg".into());

    let job_id = uuid::Uuid::new_v4().to_string();
    let jobs = state.jobs.clone();

    let range_json = serde_json::to_string(&range).unwrap_or_default();
    recovery::write_job_info(&config::temp_dir(), &input, &output, "trim", &range_json);

    let do_strip = strip_audio.unwrap_or(false);

    if smart_cut {
        do_smart_cut(&input, &output, &range, &ffmpeg, &job_id, &app, &jobs, do_strip).await?;
    } else {
        let cmd = commands::build_trim_keyframe(&input, &output, &range, do_strip);
        let ffmpeg_c = ffmpeg.clone();
        let jid = job_id.clone();
        let duration = range.end - range.start;
        let app_c = app.clone();
        let jobs_c = jobs.clone();

        tokio::task::spawn_blocking(move || {
            runner::run_ffmpeg(&ffmpeg_c, &cmd, &jid, duration, "encoding", &app_c, &jobs_c)
        })
        .await
        .map_err(|e| e.to_string())??;
    }

    recovery::delete_job_info(&config::temp_dir());

    let out_info = {
        let path = output.clone();
        let ffmpeg = ffmpeg.clone();
        tokio::task::spawn_blocking(move || probe::probe_video(&path, &ffmpeg))
            .await
            .map_err(|e| e.to_string())??
    };

    let file_size = fs::metadata(&output).map(|m| m.len()).unwrap_or(0);

    Ok(OutputInfo {
        path: output,
        file_size,
        duration: out_info.duration,
        width: out_info.width,
        height: out_info.height,
        video_codec: out_info.video_codec,
        video_bitrate: out_info.video_bitrate,
        audio_codec: out_info.audio_codec,
        audio_bitrate: out_info.audio_bitrate,
        attempts: 1,
    })
}

async fn do_smart_cut(
    input: &str,
    output: &str,
    range: &TrimRange,
    ffmpeg: &str,
    job_id: &str,
    app: &AppHandle,
    jobs: &runner::JobMap,
    strip_audio: bool,
) -> Result<(), String> {
    let info = {
        let input = input.to_string();
        let ffmpeg = ffmpeg.to_string();
        tokio::task::spawn_blocking(move || probe::probe_video(&input, &ffmpeg))
            .await
            .map_err(|e| e.to_string())??
    };

    let keyframes = &info.keyframe_times;

    let first_kf = keyframes
        .iter()
        .find(|&&t| t >= range.start)
        .copied()
        .unwrap_or(range.start);

    let last_kf = keyframes
        .iter()
        .rev()
        .find(|&&t| t <= range.end)
        .copied()
        .unwrap_or(range.end);

    let has_audio = info.audio_codec.is_some() && !strip_audio;

    if first_kf >= last_kf || (range.end - range.start) < 5.0 {
        let cmd = commands::build_trim_keyframe(input, output, range, strip_audio);
        let ffmpeg = ffmpeg.to_string();
        let jid = job_id.to_string();
        let dur = range.end - range.start;
        let app = app.clone();
        let jobs = jobs.clone();
        tokio::task::spawn_blocking(move || {
            runner::run_ffmpeg(&ffmpeg, &cmd, &jid, dur, "encoding", &app, &jobs)
        })
        .await
        .map_err(|e| e.to_string())??;
        return Ok(());
    }

    let work_dir = config::ensure_temp_subdir(&format!("smartcut/{}", job_id));
    let head_path = work_dir.join("head.mp4").to_string_lossy().to_string();
    let middle_path = work_dir.join("middle.mp4").to_string_lossy().to_string();
    let tail_path = work_dir.join("tail.mp4").to_string_lossy().to_string();
    let filelist_path = work_dir.join("filelist.txt").to_string_lossy().to_string();

    // head
    {
        let cmd = commands::build_smart_cut_head(input, &head_path, range.start, first_kf, has_audio);
        let ffmpeg = ffmpeg.to_string();
        let jid = job_id.to_string();
        let dur = first_kf - range.start;
        let app = app.clone();
        let jobs = jobs.clone();
        tokio::task::spawn_blocking(move || {
            runner::run_ffmpeg(&ffmpeg, &cmd, &jid, dur, "encoding", &app, &jobs)
        })
        .await
        .map_err(|e| e.to_string())??;
    }

    // middle
    {
        let cmd = commands::build_smart_cut_middle(input, &middle_path, first_kf, last_kf);
        let ffmpeg = ffmpeg.to_string();
        tokio::task::spawn_blocking(move || runner::run_ffmpeg_silent(&ffmpeg, &cmd))
            .await
            .map_err(|e| e.to_string())??;
    }

    // tail
    {
        let cmd = commands::build_smart_cut_tail(input, &tail_path, last_kf, range.end, has_audio);
        let ffmpeg = ffmpeg.to_string();
        let jid = job_id.to_string();
        let dur = range.end - last_kf;
        let app = app.clone();
        let jobs = jobs.clone();
        tokio::task::spawn_blocking(move || {
            runner::run_ffmpeg(&ffmpeg, &cmd, &jid, dur, "encoding", &app, &jobs)
        })
        .await
        .map_err(|e| e.to_string())??;
    }

    // concat
    let filelist_content = format!(
        "file '{}'\nfile '{}'\nfile '{}'",
        head_path.replace('\\', "/"),
        middle_path.replace('\\', "/"),
        tail_path.replace('\\', "/"),
    );
    fs::write(&filelist_path, &filelist_content).map_err(|e| e.to_string())?;

    {
        let cmd = commands::build_concat(&filelist_path, output);
        let ffmpeg = ffmpeg.to_string();
        tokio::task::spawn_blocking(move || runner::run_ffmpeg_silent(&ffmpeg, &cmd))
            .await
            .map_err(|e| e.to_string())??;
    }

    // cleanup temp
    let _ = fs::remove_dir_all(&work_dir);

    Ok(())
}

#[tauri::command]
pub async fn cancel_job(job_id: String, state: State<'_, AppState>) -> Result<(), String> {
    let result = runner::cancel_job(&job_id, &state.jobs);
    recovery::delete_job_info(&config::temp_dir());
    result
}