#[macro_use]
extern crate rocket;

use rocket::fairing::{self, AdHoc};
use rocket::form::{Context, Form};
use rocket::fs::{relative, FileServer};
use rocket::request::FlashMessage;
use rocket::response::{Flash, Redirect};
use rocket::{Build, Request, Rocket};
use rocket_dyn_templates::{context, Template};

use sea_orm::{entity::*, query::*};
use sea_orm_rocket::{Connection, Database};

mod pool;
use pool::Db;

mod setup;

mod post;
pub use post::Entity as Post;

const DEFAULT_POSTS_PER_PAGE: usize = 5;

#[get("/new")]
async fn new() -> Template {
    Template::render("new", &Context::default())
}

#[post("/", data = "<post_form>")]
async fn create(conn: Connection<'_, Db>, post_form: Form<post::Model>) -> Flash<Redirect> {
    let db = conn.into_inner();

    let form = post_form.into_inner();

    post::ActiveModel {
        title: Set(form.title.to_owned()),
        text: Set(form.text.to_owned()),
        ..Default::default()
    }
    .save(db)
    .await
    .expect("could not insert post");

    Flash::success(Redirect::to("/"), "Post successfully added.")
}

#[post("/<id>", data = "<post_form>")]
async fn update(
    conn: Connection<'_, Db>,
    id: i32,
    post_form: Form<post::Model>,
) -> Flash<Redirect> {
    let db = conn.into_inner();

    let post: post::ActiveModel = Post::find_by_id(id).one(db).await.unwrap().unwrap().into();

    let form = post_form.into_inner();

    db.transaction::<_, (), sea_orm::DbErr>(|txn| {
        Box::pin(async move {
            post::ActiveModel {
                id: post.id,
                title: Set(form.title.to_owned()),
                text: Set(form.text.to_owned()),
            }
            .save(txn)
            .await
            .expect("could not edit post");

            Ok(())
        })
    })
    .await
    .unwrap();

    Flash::success(Redirect::to("/"), "Post successfully edited.")
}

#[get("/?<page>&<posts_per_page>")]
async fn list(
    conn: Connection<'_, Db>,
    page: Option<usize>,
    posts_per_page: Option<usize>,
    flash: Option<FlashMessage<'_>>,
) -> Template {
    let db = conn.into_inner();

    // Set page number and items per page
    let page = page.unwrap_or(1);
    let posts_per_page = posts_per_page.unwrap_or(DEFAULT_POSTS_PER_PAGE);
    if page == 0 {
        panic!("Page number cannot be zero");
    }

    // Setup paginator
    let paginator = Post::find()
        .order_by_asc(post::Column::Id)
        .paginate(db, posts_per_page);
    let num_pages = paginator.num_pages().await.ok().unwrap();

    // Fetch paginated posts
    let posts = paginator
        .fetch_page(page - 1)
        .await
        .expect("could not retrieve posts");

    Template::render(
        "index",
        context! {
            page: page,
            posts_per_page: posts_per_page,
            num_pages: num_pages,
            posts: posts,
            flash: flash.map(FlashMessage::into_inner),
        },
    )
}

#[get("/<id>")]
async fn edit(conn: Connection<'_, Db>, id: i32) -> Template {
    let db = conn.into_inner();

    let post: Option<post::Model> = Post::find_by_id(id)
        .one(db)
        .await
        .expect("could not find post");

    Template::render(
        "edit",
        context! {
            post: post,
        },
    )
}

#[delete("/<id>")]
async fn delete(conn: Connection<'_, Db>, id: i32) -> Flash<Redirect> {
    let db = conn.into_inner();

    let post: post::ActiveModel = Post::find_by_id(id).one(db).await.unwrap().unwrap().into();

    post.delete(db).await.unwrap();

    Flash::success(Redirect::to("/"), "Post successfully deleted.")
}

#[delete("/")]
async fn destroy(conn: Connection<'_, Db>) -> Result<(), rocket::response::Debug<sea_orm::DbErr>> {
    let db = conn.into_inner();

    Post::delete_many().exec(db).await.unwrap();
    Ok(())
}

#[catch(404)]
pub fn not_found(req: &Request<'_>) -> Template {
    Template::render(
        "error/404",
        context! {
            uri: req.uri()
        },
    )
}

async fn run_migrations(rocket: Rocket<Build>) -> fairing::Result {
    let conn = &Db::fetch(&rocket).unwrap().conn;
    let _ = setup::create_post_table(conn).await;
    Ok(rocket)
}

#[launch]
fn rocket() -> _ {
    rocket::build()
        .attach(Db::init())
        .attach(AdHoc::try_on_ignite("Migrations", run_migrations))
        .mount("/", FileServer::from(relative!("/static")))
        .mount(
            "/",
            routes![new, create, delete, destroy, list, edit, update],
        )
        .register("/", catchers![not_found])
        .attach(Template::fairing())
}