use crate::file_hosting::S3Host;
use crate::ratelimit::errors::ARError;
use crate::ratelimit::memory::{MemoryStore, MemoryStoreActor};
use crate::ratelimit::middleware::RateLimiter;
use crate::util::env::{parse_strings_from_var, parse_var};
use actix_cors::Cors;
use actix_web::{http, web, App, HttpServer};
use env_logger::Env;
use gumdrop::Options;
use log::{error, info, warn};
use search::indexing::index_projects;
use search::indexing::IndexingSettings;
use std::sync::atomic::Ordering;
use std::sync::Arc;

mod database;
mod file_hosting;
mod health;
mod models;
mod ratelimit;
mod routes;
mod scheduler;
mod search;
mod util;
mod validate;

#[derive(Debug, Options)]
struct Config {
    #[options(help = "Print help message")]
    help: bool,

    #[options(no_short, help = "Skip indexing on startup")]
    skip_first_index: bool,
    #[options(no_short, help = "Reset the settings of the indices")]
    reconfigure_indices: bool,
    #[options(no_short, help = "Reset the documents in the indices")]
    reset_indices: bool,

    #[options(
        no_short,
        help = "Allow missing environment variables on startup. This is a bad idea, but it may work in some cases."
    )]
    allow_missing_vars: bool,
}

#[derive(Clone)]
pub struct Pepper {
    pub pepper: String,
}

#[actix_rt::main]
async fn main() -> std::io::Result<()> {
    dotenv::dotenv().ok();
    env_logger::Builder::from_env(Env::default().default_filter_or("info")).init();

    let config = Config::parse_args_default_or_exit();

    if check_env_vars() {
        error!("Some environment variables are missing!");
        if !config.allow_missing_vars {
            return Err(std::io::Error::new(
                std::io::ErrorKind::Other,
                "Missing required environment variables",
            ));
        }
    }

    let search_config = search::SearchConfig {
        address: dotenv::var("MEILISEARCH_ADDR").unwrap(),
        key: dotenv::var("MEILISEARCH_KEY").unwrap(),
    };

    if config.reset_indices {
        info!("Resetting indices");
        search::indexing::reset_indices(&search_config)
            .await
            .unwrap();
        return Ok(());
    } else if config.reconfigure_indices {
        info!("Reconfiguring indices");
        search::indexing::reconfigure_indices(&search_config)
            .await
            .unwrap();
        return Ok(());
    }

    // Allow manually skipping the initial indexing for quicker iteration
    // and startup times.
    let skip_initial = config.skip_first_index;
    if skip_initial {
        info!("Skipping initial indexing");
    }

    database::check_for_migrations()
        .await
        .expect("An error occurred while running migrations.");

    // Database Connector
    let pool = database::connect()
        .await
        .expect("Database connection failed");

    let storage_backend = dotenv::var("STORAGE_BACKEND").unwrap_or_else(|_| "local".to_string());

    let file_host: Arc<dyn file_hosting::FileHost + Send + Sync> = match storage_backend.as_str() {
        "backblaze" => Arc::new(
            file_hosting::BackblazeHost::new(
                &dotenv::var("BACKBLAZE_KEY_ID").unwrap(),
                &dotenv::var("BACKBLAZE_KEY").unwrap(),
                &dotenv::var("BACKBLAZE_BUCKET_ID").unwrap(),
            )
            .await,
        ),
        "s3" => Arc::new(
            S3Host::new(
                &*dotenv::var("S3_BUCKET_NAME").unwrap(),
                &*dotenv::var("S3_REGION").unwrap(),
                &*dotenv::var("S3_URL").unwrap(),
                &*dotenv::var("S3_ACCESS_TOKEN").unwrap(),
                &*dotenv::var("S3_SECRET").unwrap(),
            )
            .unwrap(),
        ),
        "local" => Arc::new(file_hosting::MockHost::new()),
        _ => panic!("Invalid storage backend specified. Aborting startup!"),
    };

    let mut scheduler = scheduler::Scheduler::new();

    // The interval in seconds at which the local database is indexed
    // for searching.  Defaults to 1 hour if unset.
    let local_index_interval =
        std::time::Duration::from_secs(parse_var("LOCAL_INDEX_INTERVAL").unwrap_or(3600));

    let mut skip = skip_initial;
    let pool_ref = pool.clone();
    let search_config_ref = search_config.clone();
    scheduler.run(local_index_interval, move || {
        let pool_ref = pool_ref.clone();
        let search_config_ref = search_config_ref.clone();
        let local_skip = skip;
        if skip {
            skip = false;
        }
        async move {
            if local_skip {
                return;
            }
            info!("Indexing local database");
            let settings = IndexingSettings { index_local: true };
            let result = index_projects(pool_ref, settings, &search_config_ref).await;
            if let Err(e) = result {
                warn!("Local project indexing failed: {:?}", e);
            }
            info!("Done indexing local database");
        }
    });

    let pool_ref = pool.clone();
    scheduler.run(std::time::Duration::from_secs(15 * 60), move || {
        let pool_ref = pool_ref.clone();
        // Use sqlx to delete records more than an hour old
        info!("Deleting old records from temporary tables");

        async move {
            let downloads_result = sqlx::query!(
                "
                DELETE FROM downloads
                WHERE date < (CURRENT_DATE - INTERVAL '30 minutes ago')
                "
            )
            .execute(&pool_ref)
            .await;

            if let Err(e) = downloads_result {
                warn!(
                    "Deleting old records from temporary table downloads failed: {:?}",
                    e
                );
            }

            let states_result = sqlx::query!(
                "
                DELETE FROM states
                WHERE expires < CURRENT_DATE
                "
            )
            .execute(&pool_ref)
            .await;

            if let Err(e) = states_result {
                warn!(
                    "Deleting old records from temporary table states failed: {:?}",
                    e
                );
            }

            info!("Finished deleting old records from temporary tables");
        }
    });

    let indexing_queue = Arc::new(search::indexing::queue::CreationQueue::new());

    let mut skip = skip_initial;
    let queue_ref = indexing_queue.clone();
    let search_config_ref = search_config.clone();
    scheduler.run(std::time::Duration::from_secs(15 * 60), move || {
        let queue_ref = queue_ref.clone();
        let search_config_ref = search_config_ref.clone();
        let local_skip = skip;
        if skip {
            skip = false;
        }
        async move {
            if local_skip {
                return;
            }
            info!("Indexing created project queue");
            let result = queue_ref.index(&search_config_ref).await;
            if let Err(e) = result {
                warn!("Indexing created projects failed: {:?}", e);
            }
            crate::health::SEARCH_READY.store(true, Ordering::Release);
            info!("Done indexing created project queue");
        }
    });

    scheduler::schedule_versions(&mut scheduler, pool.clone(), skip_initial);

    let ip_salt = Pepper {
        pepper: crate::models::ids::Base62Id(crate::models::ids::random_base62(11)).to_string(),
    };

    let store = MemoryStore::new();

    info!("Starting Actix HTTP server!");

    // Init App
    HttpServer::new(move || {
        App::new()
            .wrap(
                Cors::default()
                    .allowed_methods(["GET", "POST", "DELETE", "PATCH", "PUT"])
                    .allowed_headers([http::header::AUTHORIZATION, http::header::ACCEPT])
                    .allowed_header(http::header::CONTENT_TYPE)
                    .allow_any_origin()
                    .max_age(3600),
            )
            .wrap(
                RateLimiter::new(MemoryStoreActor::from(store.clone()).start())
                    .with_identifier(|req| {
                        let connection_info = req.connection_info();
                        let ip =
                            String::from(if parse_var("CLOUDFLARE_INTEGRATION").unwrap_or(false) {
                                if let Some(header) = req.headers().get("CF-Connecting-IP") {
                                    header.to_str().map_err(|_| ARError::IdentificationError)?
                                } else {
                                    connection_info
                                        .peer_addr()
                                        .ok_or(ARError::IdentificationError)?
                                }
                            } else {
                                connection_info
                                    .peer_addr()
                                    .ok_or(ARError::IdentificationError)?
                            });

                        Ok(ip)
                    })
                    .with_interval(std::time::Duration::from_secs(60))
                    .with_max_requests(300)
                    .with_ignore_ips(
                        parse_strings_from_var("RATE_LIMIT_IGNORE_IPS").unwrap_or_default(),
                    ),
            )
            .app_data(web::Data::new(pool.clone()))
            .app_data(web::Data::new(file_host.clone()))
            .app_data(web::Data::new(indexing_queue.clone()))
            .app_data(web::Data::new(search_config.clone()))
            .app_data(web::Data::new(ip_salt.clone()))
            .configure(routes::v1_config)
            .configure(routes::v2_config)
            .service(routes::index_get)
            .service(routes::health_get)
            .service(web::scope("/maven/").configure(routes::maven_config))
            .default_service(web::get().to(routes::not_found))
    })
    .bind(dotenv::var("BIND_ADDR").unwrap())?
    .run()
    .await
}

// This is so that env vars not used immediately don't panic at runtime
fn check_env_vars() -> bool {
    let mut failed = false;

    fn check_var<T: std::str::FromStr>(var: &'static str) -> bool {
        let check = parse_var::<T>(var).is_none();
        if check {
            warn!(
                "Variable `{}` missing in dotenv or not of type `{}`",
                var,
                std::any::type_name::<T>()
            );
        }
        check
    }

    if parse_strings_from_var("RATE_LIMIT_IGNORE_IPS").is_none() {
        warn!("Variable `RATE_LIMIT_IGNORE_IPS` missing in dotenv or not a json array of strings");
        failed |= true;
    }

    if parse_strings_from_var("WHITELISTED_MODPACK_DOMAINS").is_none() {
        warn!("Variable `WHITELISTED_MODPACK_DOMAINS` missing in dotenv or not a json array of strings");
        failed |= true;
    }

    failed |= check_var::<String>("SITE_URL");
    failed |= check_var::<String>("CDN_URL");
    failed |= check_var::<String>("DATABASE_URL");
    failed |= check_var::<String>("MEILISEARCH_ADDR");
    failed |= check_var::<String>("MEILISEARCH_KEY");
    failed |= check_var::<String>("BIND_ADDR");

    failed |= check_var::<String>("STORAGE_BACKEND");

    let storage_backend = dotenv::var("STORAGE_BACKEND").ok();
    match storage_backend.as_deref() {
        Some("backblaze") => {
            failed |= check_var::<String>("BACKBLAZE_KEY_ID");
            failed |= check_var::<String>("BACKBLAZE_KEY");
            failed |= check_var::<String>("BACKBLAZE_BUCKET_ID");
        }
        Some("s3") => {
            failed |= check_var::<String>("S3_ACCESS_TOKEN");
            failed |= check_var::<String>("S3_SECRET");
            failed |= check_var::<String>("S3_URL");
            failed |= check_var::<String>("S3_REGION");
            failed |= check_var::<String>("S3_BUCKET_NAME");
        }
        Some("local") => {
            failed |= check_var::<String>("MOCK_FILE_PATH");
        }
        Some(backend) => {
            warn!("Variable `STORAGE_BACKEND` contains an invalid value: {}. Expected \"backblaze\", \"s3\", or \"local\".", backend);
            failed |= true;
        }
        _ => {
            warn!("Variable `STORAGE_BACKEND` is not set!");
            failed |= true;
        }
    }
    failed |= check_var::<usize>("LOCAL_INDEX_INTERVAL");

    failed |= check_var::<usize>("VERSION_INDEX_INTERVAL");

    failed |= check_var::<String>("GITHUB_CLIENT_ID");
    failed |= check_var::<String>("GITHUB_CLIENT_SECRET");

    failed
}