use regex::Regex;

use tokio::stream::StreamExt;
use telegram_bot::*;

use sqlx::postgres::PgPoolOptions;
use sqlx::Row;
use sqlx::Done;

#[macro_use]
extern crate lazy_static;

use anyhow::{anyhow, Context, Result};

type Result<T> = std::result::Result<T, Box<dyn std::error::Error>>;
//type Result<T> = std::result::Result<T, Box<dyn std::error::Error>>;

#[derive(Clone)]
struct Core {
	owner: i64,
	api_key: String,
	owner_chat: UserId,
	tg: telegram_bot::Api,

					Ok(_) => {},
				};
			},
		};
		Ok(())
	}

	async fn enable(&self, source_id: &i32) -> Result<()> {
		match self.pool.acquire().await {
	async fn enable(&self, source_id: &i32, id: telegram_bot::UserId) -> Result<&str> {
		let mut conn = self.pool.acquire().await
			Err(err) => {
				self.debug(&format!("🛑 Enable fetch conn:\n{}\n{:?}", &err, &self.pool))?;
			.with_context(|| format!("🛑 Enable fetch conn:\n{:?}", &self.pool))?;
			},
			Ok(mut conn) => {
				match sqlx::query("update rsstg_source set enabled = true where source_id = $1")
					.bind(source_id)
					.execute(&mut conn).await {
		match sqlx::query("update rsstg_source set enabled = true where source_id = $1 and owner = $2")
			.bind(source_id)
			.bind(i64::from(id))
			.execute(&mut conn).await
					Err(err) => {
						self.debug(&format!("🛑 Enable source:\n{}\n{:?}", &err, &self.pool))?;
					},
					Ok(_) => {},
				}
			.with_context(|| format!("🛑 Enable source:\n\n{:?}", &self.pool))?
			.rows_affected() {
			1 => { Ok("Source disabled\\.") },
			0 => { Ok("Source not found\\.") },
			_ => { Err(anyhow!("Database error.")) },
		}
			},
		};
		Ok(())
	}

	async fn disable(&self, source_id: &i32) -> Result<()> {
		match self.pool.acquire().await {
	async fn disable(&self, source_id: &i32, id: telegram_bot::UserId) -> Result<&str> {
		let mut conn = self.pool.acquire().await
			Err(err) => {
				self.debug(&format!("🛑 Disable fetch conn:\n{}\n{:?}", &err, &self.pool))?;
			.with_context(|| format!("🛑 Disable fetch conn:\n{:?}", &self.pool))?;
			},
			Ok(mut conn) => {
				match sqlx::query("update rsstg_source set enabled = false where source_id = $1")
					.bind(source_id)
					.execute(&mut conn).await {
		match sqlx::query("update rsstg_source set enabled = false where source_id = $1 and owner = $2")
			.bind(source_id)
			.bind(i64::from(id))
			.execute(&mut conn).await
					Err(err) => {
						self.debug(&format!("🛑 Disable source:\n{}\n{:?}", &err, &self.pool))?;
					},
					Ok(_) => {},
				}
			.with_context(|| format!("🛑 Disable source:\n\n{:?}", &self.pool))?
			.rows_affected() {
			1 => { Ok("Source disabled\\.") },
			0 => { Ok("Source not found\\.") },
			_ => { Err(anyhow!("Database error.")) },
		}
			},
		};
		Ok(())
	}

	async fn autofetch(&self) -> Result<()> {
		let mut delay = chrono::Duration::minutes(5);
		let mut now;
		loop {
			match self.pool.acquire().await {

}

#[tokio::main]
async fn main() -> Result<()> {
	let mut settings = config::Config::default();
	settings.merge(config::File::with_name("rsstg"))?;

	let re_username = Regex::new(r"^@[a-zA-Z][a-zA-Z0-9_]+$")?;
	let re_link = Regex::new(r"^https?://[a-zA-Z.0-9-]+/[-_a-zA-Z.0-9/?=]+$")?;
	let re_iv_hash = Regex::new(r"^[a-f0-9]{14}$")?;

	let core = Core::new(settings).await?;

	let mut stream = core.stream();

	while let Some(update) = stream.next().await {
		match update {
		match handle(update?, &core).await {
			Ok(_) => {},
			Err(err) => {
				core.debug(&err.to_string())?;
			}
			},
			Ok(update) => {
				match update.kind {
					UpdateKind::Message(message) => {
						let mut reply: Vec<String> = vec![];
						match message.kind {
							MessageKind::Text { ref data, .. } => {
								let mut words = data.split_whitespace();
								let cmd = words.next().unwrap();
								match cmd {
		};
	}

	Ok(())
}

async fn handle(update: telegram_bot::Update, core: &Core) -> Result<()> {
	lazy_static! {
		static ref RE_USERNAME: Regex = Regex::new(r"^@[a-zA-Z][a-zA-Z0-9_]+$").unwrap();
		static ref RE_LINK: Regex = Regex::new(r"^https?://[a-zA-Z.0-9-]+/[-_a-zA-Z.0-9/?=]+$").unwrap();
		static ref RE_IV_HASH: Regex = Regex::new(r"^[a-f0-9]{14}$").unwrap();
	}

	match update.kind {
		UpdateKind::Message(message) => {
			let mut reply: Vec<String> = vec![];
			match message.kind {
				MessageKind::Text { ref data, .. } => {
					let mut words = data.split_whitespace();
					let cmd = words.next().unwrap();
					match cmd {

		// start
// start

									"/start" => {
										reply.push("We are open\\. Probably\\. Visit [channel](https://t.me/rsstg_bot_help/3) for details\\.".to_string());
									},
						"/start" => {
							reply.push("We are open\\. Probably\\. Visit [channel](https://t.me/rsstg_bot_help/3) for details\\.".to_string());
						},

		// list
// list

									"/list" => {
										match core.pool.acquire().await {
											Err(err) => {
												core.debug(&format!("🛑 Disable fetch conn:\n{}\n{:?}", &err, &core.pool))?;
											},
											Ok(mut conn) => {
												reply.push("Channels:".to_string());
												let rows = sqlx::query("select source_id, username, enabled, url, iv_hash from rsstg_source left join rsstg_channel using (channel_id) where owner = $1 order by source_id")
													.bind(i64::from(message.from.id))
													.fetch_all(&mut conn).await?;
												for row in rows.iter() {
												//while let Some(row) = rows.try_next().await? {
													let source_id: i32 = row.try_get("source_id")?;
													let username: &str = row.try_get("username")?;
													let enabled: bool = row.try_get("enabled")?;
													let url: &str = row.try_get("url")?;
													let iv_hash: Option<&str> = row.try_get("iv_hash")?;
													reply.push(format!("\n\\#️⃣ {} \\*️⃣ `{}` {}\n🔗 `{}`", source_id, username,  
														match enabled {
															true  => "🔄 enabled",
															false => "⛔ disabled",
														}, url));
													if let Some(hash) = iv_hash {
														reply.push(format!("IV `{}`", hash));
													}
												}
											},
										};
									},
						"/list" => {
							match core.pool.acquire().await {
								Err(err) => {
									core.debug(&format!("🛑 Disable fetch conn:\n{}\n{:?}", &err, &core.pool))?;
								},
								Ok(mut conn) => {
									reply.push("Channels:".to_string());
									let rows = sqlx::query("select source_id, username, enabled, url, iv_hash from rsstg_source left join rsstg_channel using (channel_id) where owner = $1 order by source_id")
										.bind(i64::from(message.from.id))
										.fetch_all(&mut conn).await?;
									for row in rows.iter() {
									//while let Some(row) = rows.try_next().await? {
										let source_id: i32 = row.try_get("source_id")?;
										let username: &str = row.try_get("username")?;
										let enabled: bool = row.try_get("enabled")?;
										let url: &str = row.try_get("url")?;
										let iv_hash: Option<&str> = row.try_get("iv_hash")?;
										reply.push(format!("\n\\#️⃣ {} \\*️⃣ `{}` {}\n🔗 `{}`", source_id, username,  
											match enabled {
												true  => "🔄 enabled",
												false => "⛔ disabled",
											}, url));
										if let Some(hash) = iv_hash {
											reply.push(format!("IV `{}`", hash));
										}
									}
								},
							};
						},

		// add
// add

									"/add" | "/update" => {
										let mut source_id: i32 = 0;
										if cmd == "/update" {
											source_id = words.next().unwrap().parse::<i32>()?;
										}
										let (channel, url, iv_hash) = (words.next().unwrap(), words.next().unwrap(), words.next());
										let ok_link = re_link.is_match(&url);
										let ok_hash = match iv_hash {
											Some(hash) => re_iv_hash.is_match(&hash),
											None => true,
										};
										if ! ok_link {
											reply.push("Link should be link to atom/rss feed, something like \"https://domain/path\"\\.".to_string());
											core.debug(&format!("Url: {:?}", &url))?;
										}
										if ! ok_hash {
											reply.push("IV hash should be 14 hex digits.".to_string());
											core.debug(&format!("IV: {:?}", &iv_hash))?;
										}
										if ok_link && ok_hash {
											let chan: Option<i64> = match sqlx::query("select channel_id from rsstg_channel where username = $1")
												.bind(channel)
												.fetch_one(&core.pool).await {
													Ok(chan) => Some(chan.try_get("channel_id")?),
													Err(sqlx::Error::RowNotFound) => {
														reply.push("Sorry, I don't know about that channel. Please, add a channel with /addchan.".to_string());
														None
													},
													Err(err) => {
														reply.push("Sorry, unknown error\\.".to_string());
														core.debug(&format!("Sorry, unknown error:\n{:#?}\n", err))?;
														None
													},
											};
											if let Some(chan) = chan {
												match if cmd == "/update" {
														sqlx::query("update rsstg_source set channel_id = $2, url = $3, iv_hash = $4, owner = $4 where source_id = $1").bind(source_id)
													} else {
														sqlx::query("insert into rsstg_source (channel_id, url, iv_hash, owner) values ($1, $2, $3, $4)")
													}
													.bind(chan)
													.bind(url)
													.bind(iv_hash)
													.bind(i64::from(message.from.id))
													.execute(&core.pool).await {
													Ok(_) => reply.push("Channel added\\.".to_string()),
													Err(sqlx::Error::Database(err)) => {
														match err.downcast::<sqlx::postgres::PgDatabaseError>().routine() {
															Some("_bt_check_unique", ) => {
																reply.push("Duplicate key\\.".to_string());
															},
															Some(_) => {
																reply.push("Database error\\.".to_string());
															},
															None => {
																reply.push("No database error extracted\\.".to_string());
															},
														};
													},
													Err(err) => {
														reply.push("Sorry, unknown error\\.".to_string());
														core.debug(&format!("Sorry, unknown error:\n{:#?}\n", err))?;
													},
												};
											};
										};
									},
						"/add" | "/update" => {
							let mut source_id: i32 = 0;
							if cmd == "/update" {
								source_id = words.next().unwrap().parse::<i32>()?;
							}
							let (channel, url, iv_hash) = (words.next().unwrap(), words.next().unwrap(), words.next());
							let ok_link = RE_LINK.is_match(&url);
							let ok_hash = match iv_hash {
								Some(hash) => RE_IV_HASH.is_match(&hash),
								None => true,
							};
							if ! ok_link {
								reply.push("Link should be link to atom/rss feed, something like \"https://domain/path\"\\.".to_string());
								core.debug(&format!("Url: {:?}", &url))?;
							}
							if ! ok_hash {
								reply.push("IV hash should be 14 hex digits.".to_string());
								core.debug(&format!("IV: {:?}", &iv_hash))?;
							}
							if ok_link && ok_hash {
								let chan: Option<i64> = match sqlx::query("select channel_id from rsstg_channel where username = $1")
									.bind(channel)
									.fetch_one(&core.pool).await {
										Ok(chan) => Some(chan.try_get("channel_id")?),
										Err(sqlx::Error::RowNotFound) => {
											let chan_id = i64::from(core.tg.send(telegram_bot::GetChat::new(telegram_bot::types::ChatRef::ChannelUsername(channel.to_string()))).await?.id());
											sqlx::query("insert into rsstg_channel (channel_id, username) values ($1, $2);")
												.bind(chan_id)
												.bind(channel)
												.execute(&core.pool).await?;
											Some(chan_id)
										},
										Err(err) => {
											reply.push("Sorry, unknown error\\.".to_string());
											core.debug(&format!("Sorry, unknown error:\n{:#?}\n", err))?;
											None
										},
								};
								if let Some(chan) = chan {
									match if cmd == "/update" {
											sqlx::query("update rsstg_source set channel_id = $2, url = $3, iv_hash = $4, owner = $4 where source_id = $1").bind(source_id)
										} else {
											sqlx::query("insert into rsstg_source (channel_id, url, iv_hash, owner) values ($1, $2, $3, $4)")
										}
										.bind(chan)
										.bind(url)
										.bind(iv_hash)
										.bind(i64::from(message.from.id))
										.execute(&core.pool).await {
										Ok(_) => reply.push("Channel added\\.".to_string()),
										Err(sqlx::Error::Database(err)) => {
											match err.downcast::<sqlx::postgres::PgDatabaseError>().routine() {
												Some("_bt_check_unique", ) => {
													reply.push("Duplicate key\\.".to_string());
												},
												Some(_) => {
													reply.push("Database error\\.".to_string());
												},
												None => {
													reply.push("No database error extracted\\.".to_string());
												},
											};
										},
										Err(err) => {
											reply.push("Sorry, unknown error\\.".to_string());
											core.debug(&format!("Sorry, unknown error:\n{:#?}\n", err))?;
										},
									};
								};
							};
						},

		// addchan
// addchan

									"/addchan" => {
										let channel = words.next().unwrap();
										if ! re_username.is_match(&channel) {
											reply.push("Usernames should be something like \"@\\[a\\-zA\\-Z]\\[a\\-zA\\-Z0\\-9\\_]+\", aren't they?".to_string());
										} else {
											let chan: Option<i64> = match sqlx::query("select channel_id from rsstg_channel where username = $1")
												.bind(channel)
												.fetch_one(&core.pool).await {
													Ok(chan) => Some(chan.try_get("channel_id")?),
													Err(sqlx::Error::RowNotFound) => None,
													Err(err) => {
														reply.push("Sorry, unknown error\\.".to_string());
														core.debug(&format!("Sorry, unknown error:\n{:#?}\n", err))?;
														None
													},
											};
											match chan {
												Some(chan) => {
													let new_chan = core.tg.send(telegram_bot::GetChat::new(telegram_bot::types::ChatId::new(chan))).await?;
													if i64::from(new_chan.id()) == chan {
														reply.push("I already know that channel\\.".to_string());
													} else {
														reply.push("Hmm, channel has changed… I'll fix it later\\.".to_string());
													};
												},
												None => {
													match core.tg.send(telegram_bot::GetChatAdministrators::new(telegram_bot::types::ChatRef::ChannelUsername(channel.to_string()))).await {
														Ok(chan_adm) => {
															let (mut me, mut user) = (false, false);
															for admin in &chan_adm {
																if admin.user.id == core.my.id {
																	me = true;
																};
																if admin.user.id == message.from.id {
																	user = true;
																};
															};
															if ! me   { reply.push("I need to be admin on that channel\\.".to_string()); };
															if ! user { reply.push("You should be admin on that channel\\.".to_string()); };
															if me && user {
																let chan_id = core.tg.send(telegram_bot::GetChat::new(telegram_bot::types::ChatRef::ChannelUsername(channel.to_string()))).await?;
																sqlx::query("insert into rsstg_channel (channel_id, username) values ($1, $2);")
																	.bind(i64::from(chan_id.id()))
																	.bind(channel)
																	.execute(&core.pool).await?;
																reply.push("Good, I know that channel now\\.\n".to_string());
															};
														},
														Err(_) => {
															reply.push("Sorry, I have no access to that chat\\.".to_string());
														},
													};
												},
											};
										};
									},
						"/addchan" => {
							let channel = words.next().unwrap();
							if ! RE_USERNAME.is_match(&channel) {
								reply.push("Usernames should be something like \"@\\[a\\-zA\\-Z]\\[a\\-zA\\-Z0\\-9\\_]+\", aren't they?".to_string());
							} else {
								let chan: Option<i64> = match sqlx::query("select channel_id from rsstg_channel where username = $1")
									.bind(channel)
									.fetch_one(&core.pool).await {
										Ok(chan) => Some(chan.try_get("channel_id")?),
										Err(sqlx::Error::RowNotFound) => None,
										Err(err) => {
											reply.push("Sorry, unknown error\\.".to_string());
											core.debug(&format!("Sorry, unknown error:\n{:#?}", err))?;
											None
										},
								};
								match chan {
									Some(chan) => {
										let new_chan = core.tg.send(telegram_bot::GetChat::new(telegram_bot::types::ChatId::new(chan))).await?;
										if i64::from(new_chan.id()) == chan {
											reply.push("I already know that channel\\.".to_string());
										} else {
											reply.push("Hmm, channel has changed… I'll fix it later\\.".to_string());
										};
									},
									None => {
										match core.tg.send(telegram_bot::GetChatAdministrators::new(telegram_bot::types::ChatRef::ChannelUsername(channel.to_string()))).await {
											Ok(chan_adm) => {
												let (mut me, mut user) = (false, false);
												for admin in &chan_adm {
													if admin.user.id == core.my.id {
														me = true;
													};
													if admin.user.id == message.from.id {
														user = true;
													};
												};
												if ! me   { reply.push("I need to be admin on that channel\\.".to_string()); };
												if ! user { reply.push("You should be admin on that channel\\.".to_string()); };
												if me && user {
													let chan_id = core.tg.send(telegram_bot::GetChat::new(telegram_bot::types::ChatRef::ChannelUsername(channel.to_string()))).await?;
													sqlx::query("insert into rsstg_channel (channel_id, username) values ($1, $2);")
														.bind(i64::from(chan_id.id()))
														.bind(channel)
														.execute(&core.pool).await?;
													reply.push("Good, I know that channel now\\.\n".to_string());
												};
											},
											Err(_) => {
												reply.push("Sorry, I have no access to that chat\\.".to_string());
											},
										};
									},
								};
							};
						},

		// check
// check

									"/check" => {
										match &words.next().unwrap().parse::<i32>() {
											Err(err) => {
												reply.push(format!("I need a number\\.\n{}", &err));
											},
											Ok(number) => {
												match &core.check(number, false).await {
													Ok(_) => {
														reply.push("Channel enabled\\.".to_string());
													}
													Err(err) => {
														core.debug(&format!("🛑 Channel check failed:\n{}", &err))?;
													},
												};
											},
										};
									},
						"/check" => {
							match &words.next().unwrap().parse::<i32>() {
								Err(err) => {
									reply.push(format!("I need a number\\.\n{}", &err));
								},
								Ok(number) => {
									match &core.check(number, false).await {
										Ok(_) => {
											reply.push("Channel enabled\\.".to_string());
										}
										Err(err) => {
											core.debug(&format!("🛑 Channel check failed:\n{}", &err))?;
										},
									};
								},
							};
						},

		// clean
// clean

									"/clean" => {
										if core.owner != i64::from(message.from.id) {
											reply.push("Reserved for testing\\.".to_string());
										} else {
											let source_id = words.next().unwrap().parse::<i32>().unwrap_or(0);
											&core.clean(source_id).await?;
										}
									},
						"/clean" => {
							if core.owner != i64::from(message.from.id) {
								reply.push("Reserved for testing\\.".to_string());
							} else {
								let source_id = words.next().unwrap().parse::<i32>().unwrap_or(0);
								&core.clean(source_id).await?;
							}
						},

		// enable
// enable

									"/enable" => {
										match &words.next().unwrap().parse::<i32>() {
											Err(err) => {
												reply.push(format!("I need a number\\.\n{}", &err));
											},
											Ok(number) => {
												match core.enable(&number).await {
						"/enable" => {
							match &words.next().unwrap().parse::<i32>() {
								Err(err) => {
									reply.push(format!("I need a number\\.\n{}", &err));
								},
								Ok(number) => {
									let result = core.enable(&number, message.from.id).await?;
													Ok(_) => {
														reply.push("Channel enabled\\.".to_string());
													}
													Err(err) => {
														core.debug(&err.to_string())?;
									reply.push(result.to_string());
													},
												};
											},
										};
									},
								},
							};
						},

		// disable
// disable

									"/disable" => {
										match &words.next().unwrap().parse::<i32>() {
											Err(err) => {
												reply.push(format!("I need a number\\.\n{}", &err));
											},
											Ok(number) => {
												match core.disable(&number).await {
						"/disable" => {
							match &words.next().unwrap().parse::<i32>() {
								Err(err) => {
									reply.push(format!("I need a number\\.\n{}", &err));
								},
								Ok(number) => {
									let result = core.disable(&number, message.from.id).await?;
													Ok(_) => {
														reply.push("Channel disabled\\.".to_string());
													}
													Err(err) => {
														core.debug(&err.to_string())?;
													},
												};
											},
									reply.push(result.to_string());
								},
							};
						},
										};
									},

									_ => {
									},
								};
							},
							_ => {
							},
						};
						if reply.len() > 0 {
							match core.tg.send(message.text_reply(reply.join("\n")).parse_mode(types::ParseMode::MarkdownV2)).await {
								Ok(_) => {},
								Err(err) => {
									dbg!(reply.join("\n"));
									println!("{}", err);
								},
							}
						}
					},
					_ => {},
				};
						_ => {
						},
					};
				},
				_ => {
				},
			};

			if reply.len() > 0 {
				match core.tg.send(message.text_reply(reply.join("\n")).parse_mode(types::ParseMode::MarkdownV2)).await {
					Ok(_) => {},
					Err(err) => {
						dbg!(reply.join("\n"));
						println!("{}", err);
					},
				}
			}
		},
		_ => {},
	};
			},

		};
	}

	Ok(())
}