//! Streams a Radio Paradise block via HTTP using pmoserver
//!
//! This example demonstrates streaming a single Radio Paradise block
//! using the StreamingFlacSink over HTTP via pmoserver. Perfect for
//! testing with VLC or other media players that support HTTP streaming.
//!
//! Architecture:
//! ```text
//! RadioParadiseStreamSource → StreamingFlacSink
//!                                    ↓
//!                              StreamHandle
//!                                    ↓
//!                            pmoserver (Axum)
//!                                    ↓
//!                        VLC / Media Player Client
//! ```
//!
//! Usage:
//!   cargo run --example stream_block --features full -- <channel_id>
//!
//! Example:
//!   cargo run --example stream_block --features full -- 0    # Main Mix
//!
//! Then open in VLC:
//!   vlc http://localhost:8080/test/stream
//!
//! For ICY metadata (Now Playing):
//!   vlc --http-continuous --icy-metadata http://localhost:8080/test/stream

use axum::{
    body::Body,
    extract::State,
    http::{HeaderMap, StatusCode},
    response::{IntoResponse, Response},
};
use pmoaudio::AudioPipelineNode;
use pmoaudio_ext::StreamingFlacSink;
use pmoflac::EncoderOptions;
use pmoparadise::{RadioParadiseClient, RadioParadiseStreamSource};
use pmoserver::{ServerBuilder, init_logging, LoggingOptions};
use std::env;
use std::sync::Arc;
use tokio_util::io::ReaderStream;
use tokio_util::sync::CancellationToken;

/// Shared application state
struct AppState {
    stream_handle: pmoaudio_ext::StreamHandle,
}

/// Main HTTP handler for streaming
async fn stream_handler(
    State(state): State<Arc<AppState>>,
    headers: HeaderMap,
) -> Result<Response, StatusCode> {
    tracing::info!("New client connected");

    // Check if client wants ICY metadata (VLC with --icy-metadata flag)
    let want_icy = headers
        .get("Icy-MetaData")
        .and_then(|v| v.to_str().ok())
        .map(|v| v == "1")
        .unwrap_or(false);

    if want_icy {
        tracing::info!("Client requested ICY metadata mode");

        // Subscribe to ICY stream
        let icy_stream = state.stream_handle.subscribe_icy();

        // Build response with ICY headers
        Ok(Response::builder()
            .status(StatusCode::OK)
            .header("Content-Type", "audio/flac")
            .header("icy-metaint", "16000")
            .header("icy-name", "Radio Paradise Stream Test")
            .header("Cache-Control", "no-cache, no-store")
            .body(Body::from_stream(ReaderStream::new(icy_stream)))
            .unwrap())
    } else {
        tracing::info!("Client requested pure FLAC mode");

        // Subscribe to pure FLAC stream
        let flac_stream = state.stream_handle.subscribe_flac();

        // Build response
        Ok(Response::builder()
            .status(StatusCode::OK)
            .header("Content-Type", "audio/flac")
            .header("Cache-Control", "no-cache, no-store")
            .body(Body::from_stream(ReaderStream::new(flac_stream)))
            .unwrap())
    }
}

/// Metadata endpoint (JSON)
async fn metadata_handler(State(state): State<Arc<AppState>>) -> impl IntoResponse {
    let metadata = state.stream_handle.get_metadata().await;
    axum::Json(metadata)
}

/// Health check endpoint
async fn health_handler() -> &'static str {
    "OK"
}

#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
    // Initialize logging via pmoserver
    init_logging(LoggingOptions {
        console_json: false,
        console_level: "info",
        file_json: false,
        file_level: "debug",
        file_path: None,
        directives: vec![
            "pmoaudio=debug".to_string(),
            "pmoaudio_ext=debug".to_string(),
            "pmoparadise=debug".to_string(),
        ],
    })?;

    tracing::info!("=== Radio Paradise HTTP Streaming Test ===");

    // Parse arguments
    let args: Vec<String> = env::args().collect();
    if args.len() < 2 {
        eprintln!("Usage: {} <channel_id>", args[0]);
        eprintln!();
        eprintln!("Streams a Radio Paradise block via HTTP for testing.");
        eprintln!();
        eprintln!("Channel IDs:");
        eprintln!("  0 - Main Mix (eclectic, diverse mix)");
        eprintln!("  1 - Mellow Mix (smooth, chilled music)");
        eprintln!("  2 - Rock Mix (classic & modern rock)");
        eprintln!("  3 - World/Etc Mix (global sounds)");
        eprintln!();
        eprintln!("After starting, open in VLC:");
        eprintln!("  vlc http://localhost:8080/stream");
        eprintln!();
        eprintln!("For ICY metadata (Now Playing):");
        eprintln!("  vlc --http-continuous --icy-metadata http://localhost:8080/stream");
        std::process::exit(1);
    }

    let channel_id: u8 = match args[1].parse() {
        Ok(id) if id <= 3 => id,
        _ => {
            eprintln!("Error: channel_id must be a number between 0 and 3");
            std::process::exit(1);
        }
    };

    tracing::info!("Channel ID: {}", channel_id);

    // ═══════════════════════════════════════════════════════════════════════════
    // Fetch block metadata
    // ═══════════════════════════════════════════════════════════════════════════

    tracing::info!("Fetching current block metadata...");
    let client = RadioParadiseClient::builder()
        .channel(channel_id)
        .build()
        .await?;

    let block = client.get_block(None).await?;

    tracing::info!("Block Information:");
    tracing::info!("  Event ID: {}", block.event);
    tracing::info!("  Songs: {}", block.song_count());
    tracing::info!("  Duration: {:.1} minutes", block.length as f64 / 60000.0);
    tracing::info!("");

    tracing::info!("Tracklist:");
    for (index, song) in block.songs_ordered() {
        tracing::info!(
            "  {:2}. {} - {} ({})",
            index + 1,
            song.artist,
            song.title,
            song.album.as_deref().unwrap_or("Unknown Album")
        );
    }
    tracing::info!("");

    // ═══════════════════════════════════════════════════════════════════════════
    // Create streaming pipeline
    // ═══════════════════════════════════════════════════════════════════════════

    tracing::info!("Creating streaming pipeline...");

    // Create Radio Paradise source
    let mut source = RadioParadiseStreamSource::new(client);
    source.push_block_id(block.event);
    tracing::debug!("RadioParadiseStreamSource created with block {}", block.event);

    // Create streaming FLAC sink
    let encoder_options = EncoderOptions {
        compression_level: 5,
        verify: false,
        ..Default::default()
    };

    let (streaming_sink, stream_handle) = StreamingFlacSink::new(encoder_options, 16);
    tracing::debug!("StreamingFlacSink created");

    // Connect source → sink
    source.register(Box::new(streaming_sink));
    tracing::info!("Pipeline connected: RadioParadiseStreamSource → StreamingFlacSink");

    // ═══════════════════════════════════════════════════════════════════════════
    // Setup pmoserver with streaming routes
    // ═══════════════════════════════════════════════════════════════════════════

    tracing::info!("Setting up pmoserver...");

    let mut server = ServerBuilder::new("RadioParadiseStreamTest", "http://localhost", 8080)
        .build();

    let app_state = Arc::new(AppState { stream_handle });

    // Add streaming route
    server.add_handler_with_state("/test/stream", stream_handler, app_state.clone()).await;

    // Add metadata route
    server.add_handler_with_state("/test/metadata", metadata_handler, app_state.clone()).await;

    // Add health check
    server.add_handler("/test/health", health_handler).await;

    tracing::info!("");
    tracing::info!("========================================");
    tracing::info!("Ready to stream!");
    tracing::info!("");
    tracing::info!("Open in VLC:");
    tracing::info!("  vlc http://localhost:8080/test/stream");
    tracing::info!("");
    tracing::info!("For ICY metadata:");
    tracing::info!("  vlc --http-continuous --icy-metadata http://localhost:8080/test/stream");
    tracing::info!("");
    tracing::info!("Metadata endpoint:");
    tracing::info!("  curl http://localhost:8080/test/metadata");
    tracing::info!("========================================");
    tracing::info!("");

    // ═══════════════════════════════════════════════════════════════════════════
    // Start pipeline and server
    // ═══════════════════════════════════════════════════════════════════════════

    let stop_token = CancellationToken::new();
    let stop_token_pipeline = stop_token.clone();

    // Start pipeline in background
    let pipeline_handle = tokio::spawn(async move {
        tracing::info!("[PIPELINE] Starting...");
        let result = Box::new(source).run(stop_token_pipeline).await;
        match &result {
            Ok(()) => tracing::info!("[PIPELINE] Completed successfully"),
            Err(e) => tracing::error!("[PIPELINE] Error: {}", e),
        }
        result
    });

    // Start pmoserver (blocks until Ctrl+C)
    tracing::info!("[SERVER] Starting pmoserver...");
    server.start().await;

    // Server stopped, cancel pipeline
    tracing::info!("Server stopped, canceling pipeline...");
    stop_token.cancel();

    // Wait for pipeline to finish
    match pipeline_handle.await {
        Ok(Ok(())) => tracing::info!("Pipeline completed successfully"),
        Ok(Err(e)) => tracing::error!("Pipeline error: {}", e),
        Err(e) => tracing::error!("Pipeline task error: {}", e),
    }

    tracing::info!("Shutdown complete");
    Ok(())
}