#![feature(proc_macro_hygiene, decl_macro)]

#[macro_use]
extern crate rocket;
#[macro_use]
extern crate serde;

use serde_json::Value;

//use rocket::request::FromSegments;
//use rocket::http::uri::Segments;
use rocket_contrib::serve::StaticFiles;
use rocket_contrib::templates::Template;

mod store;

use crate::store::form::{render_card_fields, render_empty_fields, RenderedCard, RenderedField, MapFromForm, collect_card_form};
use crate::store::Store;
use parking_lot::RwLock;

use rocket::request::Form;
use rocket::response::Redirect;
use rocket::State;
use std::env;

#[derive(Serialize, Debug)]
pub struct ListContext<'a> {
    pub fields: Vec<RenderedField<'a>>,
    pub cards: Vec<RenderedCard<'a>>,
    pub page: usize,
    pub pages: usize,
}

const PER_PAGE: usize = 20; // TODO configurable

fn find_page_with_card(store: &Store, card_id: usize) -> Option<usize> {
    if let Some((n, _)) = store
        .data
        .cards
        .iter()
        .enumerate()
        .find(|(_n, (id, _card))| **id == card_id)
    {
        Some(n / PER_PAGE)
    } else {
        None
    }
}

#[get("/?<page>")]
fn route_index(store: State<RwLock<Store>>, page: Option<usize>) -> Template {
    let rg = store.read();

    let mut page = page.unwrap_or_default();
    let n_pages = (rg.data.cards.len() as f64 / PER_PAGE as f64).ceil() as usize;

    if page >= n_pages {
        page = n_pages - 1;
    }

    let context = ListContext {
        fields: render_empty_fields(&rg),
        pages: n_pages,
        page,
        cards: rg
            .data
            .cards
            .iter()
            .skip(page * PER_PAGE)
            .take(PER_PAGE)
            .filter_map(|(id, card)| {
                if let Value::Object(ref map) = card {
                    Some(RenderedCard {
                        fields: render_card_fields(&rg, map),
                        id: *id,
                    })
                } else {
                    None
                }
            })
            .collect(),
    };

    Template::render("index", context)
}

#[derive(Serialize)]
struct AddCardContext<'a> {
    pub fields: Vec<RenderedField<'a>>,
}

#[derive(Serialize)]
struct EditCardContext<'a> {
    pub fields: Vec<RenderedField<'a>>,
    pub id: usize,
}

#[get("/add")]
fn route_add(store: State<RwLock<Store>>) -> Template {
    let rg = store.read();

    let context = AddCardContext {
        fields: render_empty_fields(&rg),
    };

    Template::render("add", context)
}

#[post("/add", data = "<form>")]
fn route_add_save(form: Form<MapFromForm>, store: State<RwLock<Store>>) -> Redirect {
    let mut wg = store.write();

    let card = collect_card_form(&wg, form.into_inner());
    let id = wg.add_card(card);

    let page = find_page_with_card(&wg, id).unwrap_or(0);
    Redirect::found(uri!(route_index: page))
}

#[get("/edit/<id>")]
fn route_edit(id: usize, store: State<RwLock<Store>>) -> Option<Template> {
    let rg = store.read();

    if let Some(Value::Object(ref map)) = rg.data.cards.get(&id) {
        let context = EditCardContext {
            fields: render_card_fields(&rg, map),
            id,
        };

        Some(Template::render("edit", context))
    } else {
        None
    }
}

#[post("/edit/<id>", data = "<form>")]
fn route_edit_save(
    id: usize,
    form: Form<MapFromForm>,
    store: State<RwLock<Store>>,
) -> Option<Redirect> {
    let mut wg = store.write();

    let card = collect_card_form(&wg, form.into_inner());
    wg.update_card(id, card);

    let page = find_page_with_card(&wg, id).unwrap_or(0);
    Some(Redirect::found(uri!(route_index: page)))
}

#[get("/delete/<id>")]
fn route_delete(id: usize, store: State<RwLock<Store>>) -> Redirect {
    let mut wg = store.write();

    // must find page before deleting
    let page = find_page_with_card(&wg, id).unwrap_or(0);
    wg.delete_card(id);

    Redirect::found(uri!(route_index: page))
}

#[get("/maintenance/reindex")]
fn route_reindex(store: State<RwLock<Store>>) -> Redirect {
    let mut wg = store.write();
    wg.rebuild_indexes();
    wg.persist();
    Redirect::found(uri!(route_index: _))
}

fn main() {
    let cwd = env::current_dir().unwrap();
    let data_dir = cwd.join("data");
    let store = Store::new(data_dir);

    rocket::ignite()
        .attach(Template::fairing())
        .manage(RwLock::new(store))
        .mount("/", StaticFiles::from(cwd.join("templates/static/")))
        .mount(
            "/",
            routes![
                route_index,
                route_add,
                route_add_save,
                route_edit,
                route_edit_save,
                route_delete,
                route_reindex,
            ],
        )
        .launch();
}