#[macro_use]
extern crate diesel;
extern crate rayon;

use actix_web::web::Data;
use actix_web_prom::PrometheusMetricsBuilder;
use diesel_migrations::{EmbeddedMigrations, MigrationHarness, embed_migrations};
use futures::stream::StreamExt;
use lazy_static::lazy_static;
use prometheus::{self, IntGauge};
use std::error::Error;
use std::sync::Mutex;
use std::sync::mpsc::channel;
use std::{collections::HashMap, io::prelude::*};
use std::{env, fs::File};
use std::{
    io::ErrorKind,
    path::{Path, PathBuf},
};
use walkdir::{DirEntry, WalkDir};

use actix_files::NamedFile;
use actix_multipart as mp;
use actix_web::{
    App, HttpRequest, HttpResponse, HttpServer, Responder, delete, get, middleware, post, put,
    web::{self, BufMut, BytesMut},
};
use anyhow::Context;
use chrono::Utc;
use diesel::sqlite::Sqlite;
use notify::{Config, EventKind, RecommendedWatcher, RecursiveMode, Watcher};
use rayon::prelude::*;

use crate::auth::login;
use crate::data::*;
use crate::database::*;
use crate::files::{
    RealFileSystem, RefreshThumbnailsMessage, is_image_or_video, is_valid_full_path, move_file,
};
use crate::otel::{extract_context_from_request, global_tracer};
use crate::service::ServiceBuilder;
use crate::state::AppState;
use crate::tags::*;
use crate::video::actors::{
    ProcessMessage, ScanDirectoryMessage, create_playlist, generate_video_thumbnail,
};
use crate::video::generate_video_gifs;
use log::{debug, error, info, trace, warn};
use opentelemetry::trace::{Span, Status, TraceContextExt, Tracer};
use opentelemetry::{KeyValue, global};

mod auth;
mod data;
mod database;
mod error;
mod files;
mod state;
mod tags;
mod video;

mod memories;
mod otel;
mod service;
#[cfg(test)]
mod testhelpers;

lazy_static! {
    static ref IMAGE_GAUGE: IntGauge = IntGauge::new(
        "imageserver_image_total",
        "Count of the images on the server"
    )
    .unwrap();
    static ref VIDEO_GAUGE: IntGauge = IntGauge::new(
        "imageserver_video_total",
        "Count of the videos on the server"
    )
    .unwrap();
}

pub const MIGRATIONS: EmbeddedMigrations = embed_migrations!();

#[get("/image")]
async fn get_image(
    _claims: Claims,
    request: HttpRequest,
    req: web::Query<ThumbnailRequest>,
    app_state: Data<AppState>,
) -> impl Responder {
    let tracer = global_tracer();
    let context = extract_context_from_request(&request);

    let mut span = tracer.start_with_context("get_image", &context);

    if let Some(path) = is_valid_full_path(&app_state.base_path, &req.path, false) {
        let image_size = req.size.unwrap_or(PhotoSize::Full);
        if image_size == PhotoSize::Thumb {
            let relative_path = path
                .strip_prefix(&app_state.base_path)
                .expect("Error stripping base path prefix from thumbnail");

            let thumbs = &app_state.thumbnail_path;
            let mut thumb_path = Path::new(&thumbs).join(relative_path);

            // If it's a video and GIF format is requested, try to serve GIF thumbnail
            if req.format == Some(ThumbnailFormat::Gif) && is_video_file(&path) {
                thumb_path = Path::new(&app_state.gif_path).join(relative_path);
                thumb_path.set_extension("gif");
            }

            trace!("Thumbnail path: {:?}", thumb_path);
            if let Ok(file) = NamedFile::open(&thumb_path) {
                span.set_status(Status::Ok);
                // The NamedFile will automatically set the correct content-type
                return file.into_response(&request);
            }
        }

        if let Ok(file) = NamedFile::open(&path) {
            span.set_status(Status::Ok);
            return file.into_response(&request);
        }

        span.set_status(Status::error("Not found"));
        HttpResponse::NotFound().finish()
    } else {
        span.set_status(Status::error("Bad photos request"));
        error!("Bad photos request: {}", req.path);
        HttpResponse::BadRequest().finish()
    }
}

fn is_video_file(path: &Path) -> bool {
    if let Some(extension) = path.extension() {
        matches!(
            extension.to_str().unwrap_or("").to_lowercase().as_str(),
            "mp4" | "mov" | "avi" | "mkv"
        )
    } else {
        false
    }
}

#[get("/image/metadata")]
async fn get_file_metadata(
    _: Claims,
    request: HttpRequest,
    path: web::Query<ThumbnailRequest>,
    app_state: Data<AppState>,
) -> impl Responder {
    let tracer = global_tracer();
    let context = extract_context_from_request(&request);
    let mut span = tracer.start_with_context("get_file_metadata", &context);
    match is_valid_full_path(&app_state.base_path, &path.path, false)
        .ok_or_else(|| ErrorKind::InvalidData.into())
        .and_then(File::open)
        .and_then(|file| file.metadata())
    {
        Ok(metadata) => {
            let response: MetadataResponse = metadata.into();
            span.add_event(
                "Metadata fetched",
                vec![KeyValue::new("file", path.path.clone())],
            );
            span.set_status(Status::Ok);

            HttpResponse::Ok().json(response)
        }
        Err(e) => {
            let message = format!("Error getting metadata for file '{}': {:?}", path.path, e);
            error!("{}", message);
            span.set_status(Status::error(message));

            HttpResponse::InternalServerError().finish()
        }
    }
}

#[post("/image")]
async fn upload_image(
    _: Claims,
    request: HttpRequest,
    mut payload: mp::Multipart,
    app_state: Data<AppState>,
) -> impl Responder {
    let tracer = global_tracer();
    let context = extract_context_from_request(&request);
    let mut span = tracer.start_with_context("upload_image", &context);

    let mut file_content: BytesMut = BytesMut::new();
    let mut file_name: Option<String> = None;
    let mut file_path: Option<String> = None;

    while let Some(Ok(mut part)) = payload.next().await {
        if let Some(content_type) = part.content_disposition() {
            debug!("{:?}", content_type);
            if let Some(filename) = content_type.get_filename() {
                debug!("Name: {:?}", filename);
                file_name = Some(filename.to_string());

                while let Some(Ok(data)) = part.next().await {
                    file_content.put(data);
                }
            } else if content_type.get_name() == Some("path") {
                while let Some(Ok(data)) = part.next().await {
                    if let Ok(path) = std::str::from_utf8(&data) {
                        file_path = Some(path.to_string())
                    }
                }
            }
        }
    }

    let path = file_path.unwrap_or_else(|| app_state.base_path.clone());
    if !file_content.is_empty() {
        let full_path = PathBuf::from(&path).join(file_name.unwrap());
        if let Some(full_path) = is_valid_full_path(
            &app_state.base_path,
            &full_path.to_str().unwrap().to_string(),
            true,
        ) {
            let context =
                opentelemetry::Context::new().with_remote_span_context(span.span_context().clone());
            tracer
                .span_builder("file write")
                .start_with_context(&tracer, &context);

            if !full_path.is_file() && is_image_or_video(&full_path) {
                let mut file = File::create(&full_path).unwrap();
                file.write_all(&file_content).unwrap();

                info!("Uploaded: {:?}", full_path);
            } else {
                warn!("File already exists: {:?}", full_path);

                let new_path = format!(
                    "{}/{}_{}.{}",
                    full_path.parent().unwrap().to_str().unwrap(),
                    full_path.file_stem().unwrap().to_str().unwrap(),
                    Utc::now().timestamp(),
                    full_path
                        .extension()
                        .expect("Uploaded file should have an extension")
                        .to_str()
                        .unwrap()
                );
                info!("Uploaded: {}", new_path);

                let mut file = File::create(new_path).unwrap();
                file.write_all(&file_content).unwrap();
            }
        } else {
            error!("Invalid path for upload: {:?}", full_path);
            span.set_status(Status::error("Invalid path for upload"));
            return HttpResponse::BadRequest().body("Path was not valid");
        }
    } else {
        span.set_status(Status::error("No file body read"));
        return HttpResponse::BadRequest().body("No file body read");
    }

    app_state.stream_manager.do_send(RefreshThumbnailsMessage);
    span.set_status(Status::Ok);

    HttpResponse::Ok().finish()
}

#[post("/video/generate")]
async fn generate_video(
    _claims: Claims,
    request: HttpRequest,
    app_state: Data<AppState>,
    body: web::Json<ThumbnailRequest>,
) -> impl Responder {
    let tracer = global_tracer();

    let context = extract_context_from_request(&request);
    let mut span = tracer.start_with_context("generate_video", &context);

    let filename = PathBuf::from(&body.path);

    if let Some(name) = filename.file_name() {
        let filename = name.to_str().expect("Filename should convert to string");
        let playlist = format!("{}/{}.m3u8", app_state.video_path, filename);
        if let Some(path) = is_valid_full_path(&app_state.base_path, &body.path, false) {
            if let Ok(child) = create_playlist(path.to_str().unwrap(), &playlist).await {
                span.add_event(
                    "playlist_created".to_string(),
                    vec![KeyValue::new("playlist-name", filename.to_string())],
                );

                span.set_status(Status::Ok);
                app_state.stream_manager.do_send(ProcessMessage(
                    playlist.clone(),
                    child,
                    // opentelemetry::Context::new().with_span(span),
                ));
            }
        } else {
            span.set_status(Status::error(format!("invalid path {:?}", &body.path)));
            return HttpResponse::BadRequest().finish();
        }

        HttpResponse::Ok().json(playlist)
    } else {
        let message = format!("Unable to get file name: {:?}", filename);
        error!("{}", message);
        span.set_status(Status::error(message));

        HttpResponse::BadRequest().finish()
    }
}

#[get("/video/stream")]
async fn stream_video(
    request: HttpRequest,
    _: Claims,
    path: web::Query<ThumbnailRequest>,
    app_state: Data<AppState>,
) -> impl Responder {
    let tracer = global::tracer("image-server");
    let context = extract_context_from_request(&request);
    let mut span = tracer.start_with_context("stream_video", &context);

    let playlist = &path.path;
    debug!("Playlist: {}", playlist);

    // Extract video playlist dir to dotenv
    if !playlist.starts_with(&app_state.video_path)
        && is_valid_full_path(&app_state.base_path, playlist, false).is_some()
    {
        span.set_status(Status::error(format!("playlist not valid {}", playlist)));

        HttpResponse::BadRequest().finish()
    } else {
        match NamedFile::open(playlist) {
            Ok(file) => {
                span.set_status(Status::Ok);
                file.into_response(&request)
            }
            _ => {
                span.set_status(Status::error(format!("playlist not found {}", playlist)));
                HttpResponse::NotFound().finish()
            }
        }
    }
}

#[get("/video/{path}")]
async fn get_video_part(
    request: HttpRequest,
    _: Claims,
    path: web::Path<ThumbnailRequest>,
    app_state: Data<AppState>,
) -> impl Responder {
    let tracer = global_tracer();
    let context = extract_context_from_request(&request);
    let mut span = tracer.start_with_context("get_video_part", &context);

    let part = &path.path;
    debug!("Video part: {}", part);

    let mut file_part = PathBuf::new();
    file_part.push(app_state.video_path.clone());
    file_part.push(part);
    // TODO: Do we need to guard against directory attacks here?
    match NamedFile::open(&file_part) {
        Ok(file) => {
            span.set_status(Status::Ok);
            file.into_response(&request)
        }
        _ => {
            error!("Video part not found: {:?}", file_part);
            span.set_status(Status::error(format!(
                "Video part not found '{}'",
                file_part.to_str().unwrap()
            )));
            HttpResponse::NotFound().finish()
        }
    }
}

#[get("image/favorites")]
async fn favorites(
    claims: Claims,
    request: HttpRequest,
    favorites_dao: Data<Mutex<Box<dyn FavoriteDao>>>,
) -> impl Responder {
    let tracer = global_tracer();
    let context = extract_context_from_request(&request);
    let mut span = tracer.start_with_context("get favorites", &context);

    match web::block(move || {
        favorites_dao
            .lock()
            .expect("Unable to get FavoritesDao")
            .get_favorites(claims.sub.parse::<i32>().unwrap())
    })
    .await
    {
        Ok(Ok(favorites)) => {
            let favorites = favorites
                .into_iter()
                .map(|favorite| favorite.path)
                .collect::<Vec<String>>();

            span.set_status(Status::Ok);
            HttpResponse::Ok().json(PhotosResponse {
                photos: favorites,
                dirs: Vec::new(),
            })
        }
        Ok(Err(e)) => {
            span.set_status(Status::error(format!("Error getting favorites: {:?}", e)));
            error!("Error getting favorites: {:?}", e);
            HttpResponse::InternalServerError().finish()
        }
        Err(_) => HttpResponse::InternalServerError().finish(),
    }
}

#[put("image/favorites")]
async fn put_add_favorite(
    claims: Claims,
    body: web::Json<AddFavoriteRequest>,
    favorites_dao: Data<Mutex<Box<dyn FavoriteDao>>>,
) -> impl Responder {
    if let Ok(user_id) = claims.sub.parse::<i32>() {
        let path = body.path.clone();
        match web::block::<_, Result<usize, DbError>>(move || {
            favorites_dao
                .lock()
                .expect("Unable to get FavoritesDao")
                .add_favorite(user_id, &path)
        })
        .await
        {
            Ok(Err(e)) if e.kind == DbErrorKind::AlreadyExists => {
                warn!("Favorite: {} exists for user: {}", &body.path, user_id);
                HttpResponse::Ok()
            }
            Ok(Err(e)) => {
                error!("{:?} {}. for user: {}", e, body.path, user_id);
                HttpResponse::BadRequest()
            }
            Ok(Ok(_)) => {
                info!("Adding favorite \"{}\" for userid: {}", body.path, user_id);
                HttpResponse::Created()
            }
            Err(e) => {
                error!("Blocking error while inserting favorite: {:?}", e);
                HttpResponse::InternalServerError()
            }
        }
    } else {
        error!("Unable to parse sub as i32: {}", claims.sub);
        HttpResponse::BadRequest()
    }
}

#[delete("image/favorites")]
async fn delete_favorite(
    claims: Claims,
    body: web::Query<AddFavoriteRequest>,
    favorites_dao: Data<Mutex<Box<dyn FavoriteDao>>>,
) -> impl Responder {
    if let Ok(user_id) = claims.sub.parse::<i32>() {
        let path = body.path.clone();
        web::block(move || {
            favorites_dao
                .lock()
                .expect("Unable to get favorites dao")
                .remove_favorite(user_id, path);
        })
        .await
        .unwrap();

        info!(
            "Removing favorite \"{}\" for userid: {}",
            body.path, user_id
        );
        HttpResponse::Ok()
    } else {
        error!("Unable to parse sub as i32: {}", claims.sub);
        HttpResponse::BadRequest()
    }
}

fn create_thumbnails() {
    let tracer = global_tracer();
    let span = tracer.start("creating thumbnails");

    let thumbs = &dotenv::var("THUMBNAILS").expect("THUMBNAILS not defined");
    let thumbnail_directory: &Path = Path::new(thumbs);

    let images = PathBuf::from(dotenv::var("BASE_PATH").unwrap());

    WalkDir::new(&images)
        .into_iter()
        .collect::<Vec<Result<_, _>>>()
        .into_par_iter()
        .filter_map(|entry| entry.ok())
        .filter(|entry| entry.file_type().is_file())
        .filter(|entry| {
            if is_video(entry) {
                let relative_path = &entry.path().strip_prefix(&images).unwrap();
                let thumb_path = Path::new(thumbnail_directory).join(relative_path);
                std::fs::create_dir_all(
                    thumb_path
                        .parent()
                        .unwrap_or_else(|| panic!("Thumbnail {:?} has no parent?", thumb_path)),
                )
                .expect("Error creating directory");

                let mut video_span = tracer.start_with_context(
                    "generate_video_thumbnail",
                    &opentelemetry::Context::new()
                        .with_remote_span_context(span.span_context().clone()),
                );
                video_span.set_attributes(vec![
                    KeyValue::new("type", "video"),
                    KeyValue::new("file-name", thumb_path.display().to_string()),
                ]);

                debug!("Generating video thumbnail: {:?}", thumb_path);
                generate_video_thumbnail(entry.path(), &thumb_path);
                video_span.end();
                false
            } else {
                is_image(entry)
            }
        })
        .filter(|entry| {
            let path = entry.path();
            let relative_path = &path.strip_prefix(&images).unwrap();
            let thumb_path = Path::new(thumbnail_directory).join(relative_path);
            !thumb_path.exists()
        })
        .map(|entry| (image::open(entry.path()), entry.path().to_path_buf()))
        .filter(|(img, path)| {
            if let Err(e) = img {
                error!("Unable to open image: {:?}. {}", path, e);
            }
            img.is_ok()
        })
        .map(|(img, path)| (img.unwrap(), path))
        .map(|(image, path)| (image.thumbnail(200, u32::MAX), path))
        .map(|(image, path)| {
            let relative_path = &path.strip_prefix(&images).unwrap();
            let thumb_path = Path::new(thumbnail_directory).join(relative_path);
            std::fs::create_dir_all(thumb_path.parent().unwrap())
                .expect("There was an issue creating directory");
            info!("Saving thumbnail: {:?}", thumb_path);
            image.save(thumb_path).expect("Failure saving thumbnail");
        })
        .for_each(drop);

    debug!("Finished making thumbnails");

    update_media_counts(&images);
}

fn update_media_counts(media_dir: &Path) {
    let mut image_count = 0;
    let mut video_count = 0;
    for ref entry in WalkDir::new(media_dir).into_iter().filter_map(|e| e.ok()) {
        if is_image(entry) {
            image_count += 1;
        } else if is_video(entry) {
            video_count += 1;
        }
    }

    IMAGE_GAUGE.set(image_count);
    VIDEO_GAUGE.set(video_count);
}

fn is_image(entry: &DirEntry) -> bool {
    entry
        .path()
        .extension()
        .and_then(|ext| ext.to_str())
        .map(|ext| ext.to_lowercase())
        .map(|ext| ext == "jpg" || ext == "jpeg" || ext == "png" || ext == "nef")
        .unwrap_or(false)
}

fn is_video(entry: &DirEntry) -> bool {
    entry
        .path()
        .extension()
        .and_then(|ext| ext.to_str())
        .map(|ext| ext.to_lowercase())
        .map(|ext| ext == "mp4" || ext == "mov")
        .unwrap_or(false)
}

fn main() -> std::io::Result<()> {
    if let Err(err) = dotenv::dotenv() {
        println!("Error parsing .env {:?}", err);
    }

    run_migrations(&mut connect()).expect("Failed to run migrations");

    watch_files();

    let system = actix::System::new();
    system.block_on(async {
        // Just use basic logger when running a non-release build
        #[cfg(debug_assertions)]
        {
            env_logger::init();
        }
        #[cfg(not(debug_assertions))]
        {
            otel::init_logs();
            otel::init_tracing();
        }

        create_thumbnails();
        generate_video_gifs().await;

        let app_data = Data::new(AppState::default());

        let labels = HashMap::new();
        let prometheus = PrometheusMetricsBuilder::new("api")
            .const_labels(labels)
            .build()
            .expect("Unable to build prometheus metrics middleware");

        prometheus
            .registry
            .register(Box::new(IMAGE_GAUGE.clone()))
            .unwrap();
        prometheus
            .registry
            .register(Box::new(VIDEO_GAUGE.clone()))
            .unwrap();

        let app_state = app_data.clone();
        app_state.playlist_manager.do_send(ScanDirectoryMessage {
            directory: app_state.base_path.clone(),
        });

        HttpServer::new(move || {
            let user_dao = SqliteUserDao::new();
            let favorites_dao = SqliteFavoriteDao::new();
            let tag_dao = SqliteTagDao::default();
            App::new()
                .wrap(middleware::Logger::default())
                .service(web::resource("/login").route(web::post().to(login::<SqliteUserDao>)))
                .service(
                    web::resource("/photos")
                        .route(web::get().to(files::list_photos::<SqliteTagDao, RealFileSystem>)),
                )
                .service(web::resource("/file/move").post(move_file::<RealFileSystem>))
                .service(get_image)
                .service(upload_image)
                .service(generate_video)
                .service(stream_video)
                .service(get_video_part)
                .service(favorites)
                .service(put_add_favorite)
                .service(delete_favorite)
                .service(get_file_metadata)
                .service(memories::list_memories)
                .add_feature(add_tag_services::<_, SqliteTagDao>)
                .app_data(app_data.clone())
                .app_data::<Data<RealFileSystem>>(Data::new(RealFileSystem::new(
                    app_data.base_path.clone(),
                )))
                .app_data::<Data<Mutex<SqliteUserDao>>>(Data::new(Mutex::new(user_dao)))
                .app_data::<Data<Mutex<Box<dyn FavoriteDao>>>>(Data::new(Mutex::new(Box::new(
                    favorites_dao,
                ))))
                .app_data::<Data<Mutex<SqliteTagDao>>>(Data::new(Mutex::new(tag_dao)))
                .wrap(prometheus.clone())
        })
        .bind(dotenv::var("BIND_URL").unwrap())?
        .bind("localhost:8088")?
        .run()
        .await
    })
}

fn run_migrations(
    connection: &mut impl MigrationHarness<Sqlite>,
) -> Result<(), Box<dyn Error + Send + Sync + 'static>> {
    connection.run_pending_migrations(MIGRATIONS)?;

    Ok(())
}

fn watch_files() {
    std::thread::spawn(|| {
        let (wtx, wrx) = channel();
        let mut watcher = RecommendedWatcher::new(wtx, Config::default()).unwrap();
        let base_str = dotenv::var("BASE_PATH").unwrap();
        let base_path = Path::new(&base_str);

        watcher
            .watch(base_path, RecursiveMode::Recursive)
            .context(format!("Unable to watch BASE_PATH: '{}'", base_str))
            .unwrap();

        loop {
            let ev = wrx.recv();
            if let Ok(Ok(event)) = ev {
                match event.kind {
                    EventKind::Create(create_kind) => {
                        info!(
                            "Creating thumbnails {:?} create event kind: {:?}",
                            event.paths, create_kind
                        );
                        create_thumbnails();
                    }
                    EventKind::Modify(kind) => {
                        debug!("All modified paths: {:?}", event.paths);
                        debug!("Modify kind: {:?}", kind);

                        if let Some(orig) = event.paths.first() {
                            let image_base_path = PathBuf::from(env::var("BASE_PATH").unwrap());
                            let image_relative = orig.strip_prefix(&image_base_path).unwrap();
                            if let Ok(old_thumbnail) =
                                env::var("THUMBNAILS").map(PathBuf::from).map(|mut base| {
                                    base.push(image_relative);
                                    base
                                })
                            {
                                if let Err(e) = std::fs::remove_file(&old_thumbnail) {
                                    error!(
                                        "Error removing thumbnail: {}\n{}",
                                        old_thumbnail.display(),
                                        e
                                    );
                                } else {
                                    info!("Deleted moved thumbnail: {}", old_thumbnail.display());

                                    create_thumbnails();
                                }
                            }
                        }
                    }

                    EventKind::Remove(_) => {
                        update_media_counts(&PathBuf::from(env::var("BASE_PATH").unwrap()))
                    }

                    _ => {}
                }
            };
        }
    });
}