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

use database::{BoardRow, Database, Error as DbError};
use twilight_cache_inmemory::{DefaultInMemoryCache, ResourceType};
use twilight_gateway::{Event, EventTypeFlags, Intents, Shard, ShardId, StreamExt};
use twilight_http::{Client as HttpClient, client::InteractionClient};
use twilight_model::{
	application::{
		command::{Command, CommandType},
		interaction::{
			InteractionData,
			application_command::{CommandData, CommandOptionValue},
		},
	},
	channel::message::MessageFlags,
	gateway::payload::incoming::InteractionCreate,
	http::interaction::{InteractionResponse, InteractionResponseData, InteractionResponseType},
	id::{
		Id,
		marker::{GuildMarker, InteractionMarker, UserMarker},
	},
};
use twilight_util::builder::{
	InteractionResponseDataBuilder,
	command::{CommandBuilder, IntegerBuilder, NumberBuilder, StringBuilder, UserBuilder},
};

mod database;

const APP_ID: u64 = 1363055126264283136;

#[tokio::main]
async fn main() -> anyhow::Result<()> {
	dotenv::dotenv()?;

	let db = Arc::new(Database::new("kindbloot.db"));
	db.create_tables();

	let mut shard = Shard::new(
		ShardId::ONE,
		env::var("DISCORD_TOKEN")?,
		Intents::GUILD_MESSAGES,
	);

	let http = Arc::new(HttpClient::new(env::var("DISCORD_TOKEN")?));

	let mut cache = DefaultInMemoryCache::builder()
		.resource_types(ResourceType::MESSAGE)
		.resource_types(ResourceType::MEMBER)
		.build();

	let iclient = http.interaction(Id::new(APP_ID));
	let commands_vec = commands(&iclient).await;
	iclient.set_global_commands(&commands_vec).await.unwrap();

	println!("Set commands!");

	let cmd_ap = commands_vec[1].clone();
	let cmd_ap_id = cmd_ap.id;

	let cmd_ap_global = iclient
		.global_commands()
		.await
		.unwrap()
		.models()
		.await
		.unwrap();

	for cmd in cmd_ap_global {
		println!("got appoints global? {}: {}", cmd.name, cmd.description);
	}

	while let Some(item) = shard.next_event(EventTypeFlags::all()).await {
		let Ok(event) = item else {
			eprintln!("error receiving event");
			continue;
		};

		cache.update(&event);

		tokio::spawn(handle_event(event, Arc::clone(&http), Arc::clone(&db)));
	}

	Ok(())
}

async fn handle_event(
	event: Event,
	http: Arc<HttpClient>,
	db: Arc<Database>,
) -> Result<(), Box<dyn Error + Send + Sync>> {
	match event {
		Event::InteractionCreate(create) => {
			let data = create.data.as_ref().unwrap();

			if let InteractionData::ApplicationCommand(cmd) = data {
				let guild = create.guild.as_ref().unwrap().id.unwrap();

				let command = match cmd.name.as_str() {
					"leaderboard" => Commands::Leaderboard,
					"addpoints" => Commands::AddPoints,
					_ => panic!("meow"),
				};

				command_handler(&db, http, guild, &create, command, cmd).await;
			}
		}
		Event::GatewayClose(close) => {
			println!("GatewayClose - {close:?}")
		}
		_ => (),
	}

	Ok(())
}

async fn commands(ic: &InteractionClient<'_>) -> Vec<Command> {
	let leaderboard = CommandBuilder::new(
		"leaderboard",
		"View the server leaderboard",
		CommandType::ChatInput,
	)
	.build();

	let addpoints = CommandBuilder::new(
		"addpoints",
		"Give someone, or multiple people, points!",
		CommandType::ChatInput,
	)
	.option(IntegerBuilder::new("points", "number of points").required(true))
	.option(StringBuilder::new("users", "person to give the points").required(true))
	.validate()
	.unwrap()
	.build();

	vec![leaderboard, addpoints]
}

async fn command_handler(
	db: &Database,
	http: Arc<HttpClient>,
	guild: Id<GuildMarker>,
	create: &InteractionCreate,
	command: Commands,
	command_data: &CommandData,
) {
	match command {
		Commands::Leaderboard => {
			let data = get_leaderboard(&db, guild);

			let response = InteractionResponse {
				kind: InteractionResponseType::ChannelMessageWithSource,
				data: Some(data),
			};

			let iclient = http.interaction(Id::new(APP_ID));
			iclient
				.create_response(create.id, &create.token, &response)
				.await
				.unwrap();
		}
		Commands::AddPoints => {
			let data = add_points(&db, &http, guild, command_data).await;

			let response = InteractionResponse {
				kind: InteractionResponseType::ChannelMessageWithSource,
				data: Some(data),
			};

			let iclient = http.interaction(Id::new(APP_ID));
			iclient
				.create_response(create.id, &create.token, &response)
				.await
				.unwrap();
		}
	}
}

fn get_leaderboard(db: &Database, guild: Id<GuildMarker>) -> InteractionResponseData {
	let board = db.get_leaderboard(guild.get());

	match board {
		Err(DbError::TableNotExist) => InteractionResponseDataBuilder::new()
			.content(
				"❌ No leaderboard exists for this server! Create a leaderboard by giving someone points!",
			)
			.build(),
		Err(DbError::UserNotExist) => unreachable!(),
		Ok(data) => {
			let str = data
				.into_iter()
				.map(|br| format!("{}: {}", br.user_handle, br.points))
				.collect::<Vec<String>>()
				.join("\n");

			InteractionResponseDataBuilder::new().content(str).build()
		}
	}
}

macro_rules! aumau {
	($meow:expr) => {
		$meow.await.unwrap().model().await.unwrap()
	};
}

async fn add_points(
	db: &Database,
	http: &HttpClient,
	guild: Id<GuildMarker>,
	data: &CommandData,
) -> InteractionResponseData {
	let mut points = None;
	let mut users: Vec<Id<UserMarker>> = vec![];

	for opt in &data.options {
		match opt.name.as_str() {
			"points" => match opt.value {
				CommandOptionValue::Integer(num) => points = Some(num),
				_ => unreachable!(),
			},
			"users" => match &opt.value {
				CommandOptionValue::String(raw) => {
					println!("raw: {raw}");
					let mentions = extract_mentions(&raw);
					users = mentions;
				}
				_ => unreachable!(),
			},
			_ => unreachable!(),
		}
	}

	if db.get_leaderboard(guild.get()).is_err() {
		db.create_leaderboard(guild.get()).unwrap();
	}

	for user in &users {
		match db.give_user_points(guild.get(), user.get(), points.unwrap()) {
			Err(DbError::UserNotExist) => {
				let member = aumau!(http.guild_member(guild, *user));
				let row = BoardRow {
					user_id: user.get(),
					user_handle: member.user.name,
					user_nickname: member.nick.or(member.user.global_name),
					points: points.unwrap(),
				};
				db.add_user_to_leaderboard(guild.get(), row).unwrap();
			}
			_ => (),
		}
	}

	let meow = users
		.into_iter()
		.map(|u| format!("<@{u}>"))
		.collect::<Vec<String>>()
		.join(", ");

	InteractionResponseDataBuilder::new()
		.content(format!("added {} points to {meow}", points.unwrap()))
		.build()
}

enum Commands {
	Leaderboard,
	AddPoints,
}

fn extract_mentions(mut raw: &str) -> Vec<Id<UserMarker>> {
	let mut ret = vec![];

	loop {
		let Some(start) = raw.find("<@") else {
			break;
		};

		let Some(end) = raw.find('>') else {
			break;
		};

		let id_str = &raw[start + 2..end];
		raw = &raw[end + 1..];

		let Ok(id) = u64::from_str_radix(id_str, 10) else {
			continue;
		};

		ret.push(Id::new(id));
	}

	ret
}