// what server scripts get, see "Server scripts" in MODS.md
import type { EventSignal, Face, Id, ItemStack, ModInfo, Position } from "./shared.ts";

export type { EventSignal, Face, Id, ItemStack, ModInfo, Position } from "./shared.ts";

export interface ServerContext {
	mod: ModInfo;
	components: ComponentRegistry; // only during setup
	commands: CommandRegistry; // only during setup
	events: { before: ServerBeforeEvents; after: ServerAfterEvents };
	system: System;
	world: ServerWorld;
	players: PlayerList;
	containers: ContainerApi;
	recipes: RecipeApi;
	ui: ServerUi;
	net: ServerNet;
	storage: ModStorage;
	log(...args: unknown[]): void;
}

// components

export interface BlockRef {
	readonly id: Id;
	readonly x: number;
	readonly y: number;
	readonly z: number;
	// tile data, any json value. saved with the world, never sent to clients
	// deno-lint-ignore no-explicit-any
	data: any;
}

// P is the component's params from the block json
// deno-lint-ignore no-explicit-any
export interface BlockComponent<P = any> {
	on_create?(block: BlockRef, params: P): void;
	on_break?(block: BlockRef, params: P, player: Player | undefined): void;
	on_click?(block: BlockRef, params: P, player: Player): void;
	// return true if it did something, so no block gets placed
	on_interact?(block: BlockRef, params: P, player: Player): boolean;
	on_tick?(block: BlockRef, params: P, dt: number): void;
	on_second?(block: BlockRef, params: P, dt: number): void;
}

// deno-lint-ignore no-explicit-any
export interface ItemComponent<P = any> {
	on_create?(item: ItemStack, params: P): void;
	get_lore?(item: ItemStack, params: P): string;
	on_use?(item: ItemStack, params: P, player: Player): void;
}

export interface ComponentRegistry {
	register_block<P>(id: Id, component: BlockComponent<P>): void;
	register_item<P>(id: Id, component: ItemComponent<P>): void;
}

// commands

export interface Command {
	description: string;
	usage: string;
	run(args: string[], player: Player): void;
}

export interface CommandRegistry {
	register(name: string, command: Command): void;
}

// events

export interface Cancelable {
	cancel: boolean;
}

export interface BlockBreakEvent {
	readonly player: Player;
	readonly block: BlockRef;
	readonly item: ItemStack | undefined;
}

export interface BlockPlaceEvent {
	readonly player: Player;
	readonly block: { readonly id: Id } & Position;
	readonly face: Face;
	readonly item: ItemStack | undefined;
}

export interface BlockInteractEvent {
	readonly player: Player;
	readonly block: BlockRef;
	readonly item: ItemStack | undefined;
}

export interface ChatSendEvent {
	readonly player: Player;
	message: string;
}

export interface ServerBeforeEvents {
	block_break: EventSignal<BlockBreakEvent & Cancelable>;
	block_place: EventSignal<BlockPlaceEvent & Cancelable>;
	block_interact: EventSignal<BlockInteractEvent & Cancelable>;
	chat_send: EventSignal<ChatSendEvent & Cancelable>;
}

export interface ServerAfterEvents {
	block_break: EventSignal<BlockBreakEvent>;
	block_place: EventSignal<BlockPlaceEvent>;
	block_interact: EventSignal<BlockInteractEvent>;
	chat_send: EventSignal<Readonly<ChatSendEvent>>;
	player_join: EventSignal<{ readonly player: Player }>;
	player_leave: EventSignal<{ readonly player: Player }>;
	server_start: EventSignal<Record<never, never>>;
	tick: EventSignal<{ readonly dt: number }>;
}

// world and players

export interface ServerWorld {
	get_block(x: number, y: number, z: number): Id | undefined; // undefined when the chunk isn't loaded
	set_block(x: number, y: number, z: number, id: Id): boolean; // runs on_break / on_create, synced to everyone
	get_state(x: number, y: number, z: number, name: string): number | undefined;
	set_state(x: number, y: number, z: number, name: string, value: number): boolean;
	get_block_data<T>(x: number, y: number, z: number): T | undefined;
	is_loaded(x: number, z: number): boolean;
	readonly seed: string;
}

export interface Player {
	readonly id: string;
	readonly name: string;
	readonly position: Readonly<Position>;
	readonly inventory: Container; // 36 slots, hotbar is 0-8
	readonly selected_slot: number;
	readonly held_item: ItemStack | undefined;
	give_item(id: Id, count?: number, data?: unknown): void;
	send_message(text: string): void;
	teleport(x: number, y: number, z: number): void;
}

export interface PlayerList {
	all(): Player[];
	get(id: string): Player | undefined;
	by_name(name: string): Player | undefined;
}

export interface System {
	run_timeout(fn: () => void, ticks: number): number;
	run_interval(fn: () => void, ticks: number): number;
	clear_run(handle: number): void;
	readonly current_tick: number;
}

// small key value store per mod, saved with the world
export interface ModStorage {
	get<T>(key: string): T | undefined;
	set(key: string, value: unknown): void; // json values only
	delete(key: string): void;
}

// containers and recipes

export interface Container {
	readonly id: string;
	readonly size: number;
	get(slot: number): ItemStack | undefined;
	set(slot: number, item: ItemStack | undefined): void;
	add(item: ItemStack): ItemStack | undefined; // returns what didn't fit
	on_change(fn: (slot: number) => void): () => void;
}

export interface ContainerApi {
	create(size: number): Container; // saved with the world
	get(id: string): Container | undefined;
	delete(id: string): void;
}

export interface RecipeApi {
	furnace_result(input: Id): { output: ItemStack; cook_time: number } | undefined;
	fuel_value(item: Id): number; // burn time in ticks, 0 if it isn't fuel
	is_fuel(item: Id): boolean;
	is_smeltable(item: Id): boolean;
}

// guis

export interface ActionForm {
	title: string;
	body?: string;
	buttons: { text: string; icon?: Id }[];
}

export interface MessageForm {
	title: string;
	body: string;
	buttons: [string, string];
}

export type FormField =
	| { type: "toggle"; label: string; default?: boolean }
	| { type: "slider"; label: string; min: number; max: number; step?: number; default?: number }
	| { type: "dropdown"; label: string; options: string[]; default?: number }
	| { type: "text"; label: string; placeholder?: string; default?: string; max_length?: number };

export interface ModalForm {
	title: string;
	fields: FormField[];
}

export type FormResult<T> = ({ canceled: true } & Partial<T>) | ({ canceled: false } & T);

export type SlotFilter = "smeltable" | "fuel" | ((item: ItemStack) => boolean);

export interface ContainerScreenOptions {
	title: string;
	container: Container;
	// x and y in slot units
	layout: { slot: number; x: number; y: number; filter?: SlotFilter; output_only?: boolean }[];
	player_inventory?: boolean;
	bars?: { id: string; x: number; y: number; texture: Id }[];
	labels?: { x: number; y: number; property: string }[];
}

export interface ScreenHandle<Props = unknown> {
	readonly player: Player;
	set_property(id: string, value: number): void;
	update(props: Props): void; // custom screens only
	close(): void;
	on_close(fn: () => void): void;
}

export interface ServerUi {
	message_form(player: Player, form: MessageForm): Promise<FormResult<{ selection: 0 | 1 }>>;
	action_form(player: Player, form: ActionForm): Promise<FormResult<{ selection: number }>>;
	modal_form(player: Player, form: ModalForm): Promise<FormResult<{ values: (boolean | number | string)[] }>>;
	open_container(player: Player, options: ContainerScreenOptions): ScreenHandle;
	open_screen<Props>(
		player: Player,
		id: Id,
		props: Props,
		options?: { containers?: Record<string, Container> },
	): ScreenHandle<Props>;
}

// mod channels

export interface ServerNet {
	on<T = unknown>(channel: Id, handler: (player: Player, data: T) => void): void;
	send(player: Player, channel: Id, data: unknown): void;
	broadcast(channel: Id, data: unknown): void;
}