use std::{env, error::Error};

use poem::{EndpointExt, Route, Server, listener::TcpListener};
use poem_openapi::{
    ApiResponse, Object, OpenApi, OpenApiService, SecurityScheme,
    auth::{Basic, Bearer},
    payload::{Json, PlainText},
};
use tokio::task::spawn_blocking;

struct Bookmark {
    #[allow(unused)]
    id: i32,
    title: String,
    url: String,
    description: String,
}

#[derive(SecurityScheme)]
#[oai(ty = "bearer", key_name = "X-Minibookfluxmark-Auth", key_in = "header")]
struct BearerAuth(Bearer);

impl BearerAuth {
    fn check(&self) -> bool {
        self.0.token == std::env::var("MINIBOOKFLUXMARK_ACCESS_TOKEN").unwrap()
    }
}

#[derive(SecurityScheme)]
#[oai(ty = "basic")]
struct BasicAuth(Basic);

impl BasicAuth {
    fn check(&self) -> bool {
        self.0.password == std::env::var("MINIBOOKFLUXMARK_ACCESS_TOKEN").unwrap()
    }
}

#[derive(SecurityScheme)]
enum Auth {
    BearerAuth(BearerAuth),
    BasicAuth(BasicAuth),
}

impl Auth {
    fn check(&self) -> bool {
        match self {
            Self::BasicAuth(a) => a.check(),
            Self::BearerAuth(a) => a.check(),
        }
    }
}

#[derive(Object, Clone)]
struct BookmarkRequest {
    title: String,
    url: String,
    description: String,
}

#[derive(ApiResponse)]
enum AddBookmarkResponse {
    #[oai(status = 200)]
    Ok,
    #[oai(status = 403)]
    NotAuthorized,
    #[oai(status = 500)]
    ServerError,
}

#[derive(ApiResponse)]
enum FeedResponse {
    #[oai(status = 200)]
    Ok(PlainText<String>),
    #[oai(status = 403)]
    NotAuthorized,
    #[oai(status = 500)]
    ServerError,
}

struct Api;

#[OpenApi]
impl Api {
    #[oai(path = "/add", method = "post")]
    async fn post_bookmark(&self, body: Json<BookmarkRequest>, auth: Auth) -> AddBookmarkResponse {
        if !auth.check() {
            return AddBookmarkResponse::NotAuthorized;
        }

        if let Err(e) = spawn_blocking(move || {
            let db_conn = match rusqlite::Connection::open(
                env::var("MINIBOOKFLUXMARK_DB_PATH").unwrap_or(String::from("db.sqlite")),
            ) {
                Ok(c) => c,
                Err(e) => {
                    println!("Failde to open db: {e}");
                    return Err(e);
                }
            };
            db_conn.execute(
                "insert into bookmarks (title, url, description) values (?1, ?2, ?3)",
                (&body.title, &body.url, &body.description),
            )?;

            Ok(())
        })
        .await
        {
            println!("Failed to spawn database save: {e}");
            return AddBookmarkResponse::ServerError;
        }

        AddBookmarkResponse::Ok
    }

    #[oai(path = "/feed", method = "get")]
    async fn get_feed(&self, auth: Auth) -> FeedResponse {
        if !auth.check() {
            return FeedResponse::NotAuthorized;
        }

        let mut resp = String::new();
        resp.push_str(
            "<?xml version=\"1.0\" encoding=\"UTF-8\" ?>\n<rss version=\"2.0\">\n<channel>",
        );

        match spawn_blocking(move || {
            let db_conn = match rusqlite::Connection::open(
                env::var("MINIBOOKFLUXMARK_DB_PATH").unwrap_or(String::from("db.sqlite")),
            ) {
                Ok(c) => c,
                Err(e) => {
                    println!("Failde to open db: {e}");
                    return Err(e);
                }
            };
            let mut query = db_conn.prepare("select id, title, url, description from bookmarks")?;
            let bookmark_iter = query.query_map([], |row| {
                Ok(Bookmark {
                    id: row.get(0)?,
                    title: row.get(1)?,
                    url: row.get(2)?,
                    description: row.get(3)?,
                })
            })?;
            let bookmarks = Vec::from_iter(bookmark_iter.flatten());
            Ok(bookmarks)
        })
        .await
        {
            Ok(Ok(bookmarks)) => {
                for b in bookmarks {
                    resp.push_str(&format!(
                            "<item>\n<title>{}</title>\n<link>{}</link>\n<description>{}</description>\n</item>",
                            xml::escape::escape_str_attribute(&b.title),
                            xml::escape::escape_str_attribute(&b.url),
                            xml::escape::escape_str_attribute(&b.description)));
                }
            }
            Ok(Err(e)) => {
                println!("Failed to read database: {e}");
                return FeedResponse::ServerError;
            }
            Err(e) => {
                println!("Failed to spawn database read: {e}");
                return FeedResponse::ServerError;
            }
        }

        resp.push_str("</channel>\n</rss>");

        FeedResponse::Ok(PlainText(resp))
    }
}

#[tokio::main]
async fn main() -> Result<(), Box<dyn Error>> {
    match spawn_blocking(move || {
            let db_conn = match rusqlite::Connection::open(
                env::var("MINIBOOKFLUXMARK_DB_PATH").unwrap_or(String::from("db.sqlite")),
            ) {
                Ok(c) => c,
                Err(e) => {
                    println!("Failde to open db: {e}");
                    return;
                }
            };
            db_conn
                .execute(
                    "create table if not exists bookmarks (id integer primary key, title text not null, url text not null, description text not null)", ()
                )
                .unwrap();
        })
        .await
        {
            Ok(_) => (),
            Err(e) => println!("Failed to spawn database save: {e}"),
        }
    let api_service = OpenApiService::new(Api, "minibookfluxmark", "0.1").server("/api/v1");
    let ui = api_service.swagger_ui();
    let app = Route::new()
        .nest("/api/v1/", api_service)
        .nest("/ui/v1/", ui)
        .with(poem::middleware::Cors::new());

    Server::new(TcpListener::bind("0.0.0.0:3000"))
        .run(app)
        .await?;

    Ok(())
}