use async_trait::async_trait;
use inbox::*;
use lazy_static::lazy_static;
use serenity::client::Client;
use serenity::framework::standard::{
    macros::{command, group},
    CommandResult, StandardFramework,
};
use serenity::model::channel::{Reaction, ReactionType};
use serenity::model::{
    channel::Message,
    id::{ChannelId, GuildId, UserId},
    prelude::User,
};
use serenity::prelude::*;
use std::fs::File;
use std::io::{self, BufRead, BufReader};
use time::Duration;
mod inbox;

const APPLICATION_NAME: &str = "didgeridoo";
const INBOX_OWNER: UserId = UserId(354694403798990848);

lazy_static! {
    static ref INBOX: Inbox = Inbox(redis::Client::open("redis://127.0.0.1/").unwrap());
}

macro_rules! send_or_log {
    ($e: expr) => {
        if let Err(e) = $e {
            eprintln!("Couldn’t send message because {:?}", e);
        }
    };
}

#[group]
#[commands(name, message, question, inbox)]
struct Fluff;
struct Handler;
#[async_trait]
impl EventHandler for Handler {
    async fn guild_ban_addition(&self, ctx: Context, guild_id: GuildId, _: User) {
        if guild_id == 427456811973738498 {
            send_or_log!({
                ChannelId(562731470423064587)
                    .say(&ctx, "Dies ist eine flauschige Diktatur!")
                    .await
            });
        }
    }

    async fn reaction_add(&self, ctx: Context, reaction: Reaction) {
        if reaction.message_id == 911630315376738384
            && reaction.emoji == ReactionType::Unicode(String::from("🧪"))
        {
            reaction
                .guild_id
                .unwrap()
                .member(&ctx, reaction.user_id.unwrap())
                .await
                .unwrap()
                .add_role(&ctx, 356421827708321795)
                .await
                .unwrap()
        }
    }

    async fn reaction_remove(&self, ctx: Context, reaction: Reaction) {
        if reaction.message_id == 911630315376738384
            && reaction.emoji == ReactionType::Unicode(String::from("🧪"))
        {
            reaction
                .guild_id
                .unwrap()
                .member(&ctx, reaction.user_id.unwrap())
                .await
                .unwrap()
                .remove_role(&ctx, 356421827708321795)
                .await
                .unwrap()
        }
    }
}

fn read_token() -> io::Result<String> {
    let reader = BufReader::new(File::open("secret")?);
    reader.lines().next().unwrap()
}

#[tokio::main]
async fn main() {
    let mut client = Client::builder(&read_token().expect("no secret file"))
        .event_handler(Handler)
        .framework(
            StandardFramework::new()
                .configure(|c| c.prefix("!"))
                .group(&FLUFF_GROUP),
        )
        .await
        .expect("Error creating client");

    INBOX.count_messages("test"); // initialize the lazy static so we know if redis is unavailable
    if let Err(why) = client.start().await {
        println!("An error occurred while running the client: {:?}", why);
    }
}

#[command]
async fn name(ctx: &Context, msg: &Message) -> CommandResult {
    if let Some((_, name)) = msg.content.split_once(' ') {
        let (name, adjustment) = name.split_once(" -").unwrap_or((name, "0"));
        let adjustment = adjustment.strip_suffix("h").unwrap_or(adjustment);
        msg.guild(&ctx)
            .await
            .unwrap()
            .edit_member(&ctx, msg.author.id, |m| m.nickname(name))
            .await?;
        let now = time::OffsetDateTime::now_utc()
            - adjustment
                .parse::<f32>()
                .map(|a| (a * 3600.0) as i64)
                .map(Duration::seconds)
                .ok()
                .unwrap_or_else(Duration::zero);
        println!(
            "{},{},{},{},{}",
            now.format("%d.%m.%Y %H:%M"),
            name,
            now.format("%y%m"),
            msg.author.id,
            now.unix_timestamp()
        );
        if msg.author.id == INBOX_OWNER {
            let msg_count = INBOX.count_messages(name);
            if msg_count > 0 {
                send_or_log!(
                    msg.reply(&ctx, format!("{} neue Nachrichten für {}", msg_count, name))
                        .await
                );
            } else {
                send_or_log!(
                    msg.reply(&ctx, format!("Keine neuen Nachrichten für {}", name))
                        .await
                );
            }
        }
    } else {
        send_or_log!(msg.reply(&ctx, "Please specify a new name.").await);
    }
    Ok(())
}

#[command]
async fn inbox(ctx: &Context, msg: &Message) -> CommandResult {
    if msg.author.id != INBOX_OWNER || !msg.is_private() {
        send_or_log!(
            msg.reply(&ctx, "You don’t have the permission to do that")
                .await
        );
        return Ok(());
    }
    if let Some((_, name)) = msg.content.split_once(' ') {
        let messages = INBOX.fetch_messages(name);
        if messages.is_empty() {
            send_or_log!(
                msg.reply(&ctx, format!("Keine neuen Nachrichten für {}.", name))
                    .await
            );
            return Ok(());
        }
        for message in &messages {
            let content = message.to_string();
            // Since we’re prepending a name (and later a time) to the message,
            // it could go over the limit of 2000 characters.
            // There is some leniency in the numbers here because unicode codepoints are meh.
            if content.len() > 1900 {
                let (first, second) = content.split_at(1500);
                send_or_log!(msg.channel_id.say(&ctx, &first).await);
                send_or_log!(msg.channel_id.say(&ctx, &second).await);
            } else {
                send_or_log!(msg.channel_id.say(&ctx, &content).await);
            }
        }
        println!("{:?}", messages); // paranoia for now so the messages aren’t lost
        if let Err(e) = INBOX.clear_messages(name) {
            eprintln!("Could not clear inbox of user {} because {}", name, e);
        }
    } else {
        send_or_log!(msg.reply(&ctx, "Kein Name für die Abfrage.").await);
    }
    Ok(())
}

#[command]
async fn message(ctx: &Context, msg: &Message) -> CommandResult {
    message_internal(ctx, msg, &msg.content).await
}

#[command]
async fn question(ctx: &Context, msg: &Message) -> CommandResult {
    message_internal(
        ctx,
        msg,
        &msg.content.replacen("!question", "!message Stream:", 1),
    )
    .await
}

async fn message_internal(ctx: &Context, msg: &Message, content: &str) -> CommandResult {
    let result = InboxMessage::parse(content, msg.author.id)
        .ok_or_else(|| {
            String::from(
                "Nachricht konnte nicht gesendet werden.
Bitte achte auf die richtige Formulierung: “!message <name>: <text>”,
z.B. “!message Lana: Hawwu!”",
            )
        })
        .and_then(|m| INBOX.queue_message(&m));
    match result {
        Ok(name) => send_or_log!(
            msg.reply(
                &ctx,
                format!("Deine Nachricht wurde erfolgreich an {} gesendet", name),
            )
            .await
        ),
        Err(e) => send_or_log!(msg.reply(&ctx, e).await),
    };
    Ok(())
}