/*
    Undercooked - a game about cooking
    Copyright 2024 metamuffin
    
    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU Affero General Public License as published by
    the Free Software Foundation, version 3 of the License only.
    
    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU Affero General Public License for more details.
    
    You should have received a copy of the GNU Affero General Public License
    along with this program.  If not, see <https://www.gnu.org/licenses/>.
    
*/
/// <reference lib="dom" />

import { MovementBase, update_movement } from "./movement.ts";
import { Gamedata, ItemIndex, Message, PacketC, PacketS, PlayerID, TileIndex } from "./protocol.ts";
import { V2, add_v2, lerp_exp_v2_mut, normalize, lerp_exp, sub_v2, length } from "./util.ts";
import { draw_ingame, draw_wait } from "./visual.ts";

const KEY_INTERACT = "KeyJ"
const KEY_BOOST = "KeyK"
const KEY_UP = "KeyW"
const KEY_DOWN = "KeyS"
const KEY_LEFT = "KeyA"
const KEY_RIGHT = "KeyD"
const KEY_CHAT = "Enter"
const KEY_CLOSE = "Escape"
const HANDLED_KEYS = [KEY_BOOST, KEY_CHAT, KEY_CLOSE, KEY_DOWN, KEY_UP, KEY_LEFT, KEY_RIGHT]

export let ctx: CanvasRenderingContext2D;
export let canvas: HTMLCanvasElement;
let ws: WebSocket;
document.addEventListener("DOMContentLoaded", () => {
    const ws_uri = window.location.protocol.endsWith("s:")
        ? `wss://${window.location.host}/`
        : `ws://${window.location.hostname}:27032/`
    ws = new WebSocket(ws_uri)
    ws.onerror = console.error
    ws.onmessage = m => {
        packet(JSON.parse(m.data) as PacketC);
    }
    ws.onclose = () => console.log("close")
    ws.onopen = () => {
        console.log("open")
        send({ type: "join", name: "test", character: Math.floor(Math.random() * 255) })
    }

    canvas = document.createElement("canvas");
    document.body.append(canvas)
    ctx = canvas.getContext("2d")!
    resize()
    globalThis.addEventListener("resize", resize)
    draw()

    document.addEventListener("keydown", ev => keyboard(ev, true))
    document.addEventListener("keyup", ev => keyboard(ev, false))
    document.addEventListener("contextmenu", ev => ev.preventDefault())
    setInterval(tick_update, 1000 / 25);
})

export interface ItemData {
    kind: ItemIndex,
    x: number,
    y: number,
    tracking?: V2,
    progress?: number
    progress_warn?: boolean
    remove_anim?: number
}
export interface PlayerData extends MovementBase {
    name: string,
    item?: ItemData,
    character: number,
    anim_position: V2,
    message?: MessageData,
}

export interface TileData {
    x: number
    y: number
    kind: TileIndex
    item?: ItemData
}
export interface MessageData {
    inner: Message
    anim_position: V2,
    anim_size: number,
}

export const players = new Map<PlayerID, PlayerData>()
export const tiles = new Map<string, TileData>()
export const items_removed = new Set<ItemData>()

export let data: Gamedata = { item_names: [], tile_names: [], spawn: [0, 0], tile_collide: [], tile_interact: [] }

export let my_id: PlayerID = -1
export const camera: V2 = { x: 0, y: 0 }
export let camera_scale = 0.05;
export const interact_target_anim: V2 = { x: 0, y: 0 }
export let interact_possible_anim: number = 0
export let interact_active_anim: number = 0
let interacting: V2 | undefined;

function send(p: PacketS) { ws.send(JSON.stringify(p)) }
function packet(p: PacketC) {
    if (!["position", "set_active", "update_map"].includes(p.type))
        console.log(p);
    switch (p.type) {
        case "init":
            my_id = p.id
            break;
        case "data":
            data = p.data
            break;
        case "add_player": {
            players.set(p.id, {
                position: { x: p.position[0], y: p.position[1], },
                anim_position: { x: p.position[0], y: p.position[1] },
                character: p.character,
                name: p.name,
                rot: 0,
                facing: { x: 0, y: 1 },
                vel: { x: 0, y: 0 },
                stamina: 0,
                boosting: false,
            })
            break;
        }
        case "remove_player":
            players.delete(p.id)
            break;
        case "position": {
            const pl = players.get(p.player)!
            const pos = { x: p.pos[0], y: p.pos[1] }
            const dist = length(sub_v2(pl.position, pos));
            // TODO this is actually not a good idea if latency is too high
            if (p.player == my_id && dist < 3) return; // we know better where we are
            pl.position.x = pos.x
            pl.position.y = pos.y
            pl.rot = p.rot
            break;
        }
        case "take_item": {
            const player = players.get(p.player)!
            const tile = tiles.get(p.tile.toString())!
            player.item = tile.item;
            player.item!.tracking = player.position
            tile.item = undefined
            break;
        }
        case "put_item": {
            const player = players.get(p.player)!
            const tile = tiles.get(p.tile.toString())!
            tile.item = player.item
            tile.item!.tracking = add_v2(tile, 0.5)
            player.item = undefined
            break;
        }
        case "set_tile_item": {
            const tile = tiles.get(p.tile.toString())!
            if (tile.item !== undefined && tile.item !== null) items_removed.add(tile.item)
            tile.item = undefined
            if (p.item !== undefined && p.item !== null) tile.item = { kind: p.item, x: p.tile[0] + 0.5, y: p.tile[1] + 0.5 }
            break;
        }
        case "set_player_item": {
            const player = players.get(p.player)!
            if (player.item !== undefined && player.item !== null) items_removed.add(player.item)
            player.item = undefined
            if (p.item !== undefined && p.item !== null) player.item = { kind: p.item, x: player.position.x + 0.5, y: player.position.y + 0.5 }
            break;
        }
        case "set_active": {
            const item = tiles.get(p.tile.toString())!.item!;
            item.progress = p.progress
            item.progress_warn = p.warn
            break;
        }
        case "update_map":
            if (p.kind !== undefined && p.kind !== null) tiles.set(p.tile.toString(), { x: p.tile[0], y: p.tile[1], kind: p.kind })
            else tiles.delete(p.tile.toString())
            break;
        case "communicate": {
            const player = players.get(p.player)!
            if (p.message) player.message = { inner: p.message, anim_size: 0., anim_position: player.anim_position }
            else player.message = undefined
            break;
        }
        case "error":
            console.warn(p.message)
            break;
        default:
            console.warn("unknown packet", p);
    }
}

export let chat: null | HTMLInputElement = null;

export const keys_down = new Set();
function keyboard(ev: KeyboardEvent, down: boolean) {
    if (down && ev.code == KEY_CHAT) return toggle_chat()
    else if (down && ev.code == KEY_CLOSE && chat) return close_chat()
    else if (chat) return
    if (HANDLED_KEYS.includes(ev.code)) ev.preventDefault()
    if (!keys_down.has(KEY_INTERACT) && ev.code == KEY_INTERACT && down) set_interact(true)
    if (keys_down.has(KEY_INTERACT) && ev.code == KEY_INTERACT && !down) set_interact(false)
    if (down && ev.code == "Numpad1") send({ type: "communicate", message: { text: "/start default-small-default" } })
    if (down && ev.code == "Numpad2") send({ type: "communicate", message: { text: "/start default-big-default" } })
    if (down && ev.code == "Numpad0") send({ type: "communicate", message: { text: "/end" } })
    if (down) keys_down.add(ev.code)
    else keys_down.delete(ev.code)
}

function close_chat() {
    if (!chat) return
    chat.remove()
    canvas.focus()
    chat = null;
}
function toggle_chat() {
    if (chat) {
        if (chat.value.length) send({ type: "communicate", message: { text: chat.value } })
        else send({ type: "communicate" })
        chat.remove()
        canvas.focus()
        chat = null;
    } else {
        chat = document.createElement("input")
        chat.type = "text"
        chat.placeholder = "Message"
        document.body.append(chat)
        chat.focus()
    }
}

export function get_interact_target(): V2 | undefined {
    if (interacting) return interacting
    const me = players.get(my_id)
    if (!me) return
    return {
        x: Math.floor(me.position.x + Math.sin(me.rot)),
        y: Math.floor(me.position.y + Math.cos(me.rot))
    }
}

function set_interact(edge: boolean) {
    if (edge) interacting = get_interact_target()
    if (interacting) send({ type: "interact", pos: [interacting.x, interacting.y], edge })
    if (!edge) interacting = undefined
}

function tick_update() {
    const p = players.get(my_id)
    if (!p) return
    send({ type: "position", pos: [p.position.x, p.position.y], rot: p.rot })
}

function frame_update(dt: number) {
    const p = players.get(my_id)
    if (!p) return

    const input = normalize({
        x: (+keys_down.has(KEY_RIGHT) - +keys_down.has(KEY_LEFT)),
        y: (+keys_down.has(KEY_DOWN) - +keys_down.has(KEY_UP))
    })
    if (interacting) input.x *= 0, input.y *= 0
    update_movement(p, dt, input, keys_down.has("KeyK"))

    const update_item = (item: ItemData) => {
        if (item.tracking) lerp_exp_v2_mut(item, item.tracking, dt * 10.)
    }
    for (const [pid, player] of players) {
        if (pid == my_id) player.anim_position.x = player.position.x, player.anim_position.y = player.position.y
        else lerp_exp_v2_mut(player.anim_position, player.position, dt * 15)
        if (player.item !== undefined && player.item !== null) update_item(player.item)
        if (player.message) player.message.anim_size = lerp_exp(player.message.anim_size, 1, dt * 3)
    }
    for (const [_, tile] of tiles) {
        if (tile.item !== undefined && tile.item !== null) update_item(tile.item)
    }

    const remove = []
    for (const item of items_removed) {
        update_item(item)
        if (item.remove_anim === undefined) item.remove_anim = 0
        item.remove_anim += dt * 4.
        if (item.remove_anim > 1.) remove.push(item)
    }
    remove.forEach(i => items_removed.delete(i))

    lerp_exp_v2_mut(camera, p.position, dt * 10.)

    const it = get_interact_target() ?? { x: 0, y: 0 };
    const possible = data.tile_interact[tiles.get([it.x, it.y].toString())?.kind ?? 0] ?? false
    lerp_exp_v2_mut(interact_target_anim, it, dt * 15.)
    interact_possible_anim = lerp_exp(interact_possible_anim, +possible, dt * 18.)
    interact_active_anim = lerp_exp(interact_active_anim, +!!interacting, dt * 15.)

    const zoom_target = Math.min(canvas.width, canvas.height) * (keys_down.has("KeyL") ? 0.05 : 0.1)
    camera_scale = lerp_exp(camera_scale, zoom_target, dt * 5)
}

function resize() {
    canvas.width = globalThis.innerWidth
    canvas.height = globalThis.innerHeight
}

let last_frame = performance.now()
function draw() {
    const now = performance.now()
    frame_update((now - last_frame) / 1000)
    last_frame = now;
    if (ws.readyState == ws.CONNECTING) draw_wait("Connecting...")
    else if (ws.readyState == ws.CLOSING) draw_wait("Closing...")
    else if (ws.readyState == ws.CLOSED) draw_wait("Disconnected")
    else if (ws.readyState == ws.OPEN) draw_ingame()
    else throw new Error(`ws state invalid`);
    requestAnimationFrame(draw)
}