use std::fs::File;
use std::io::prelude::*;

use rand::Rng;
use serenity::framework::standard::CommandResult;
use serenity::model::channel::{PermissionOverwrite, PermissionOverwriteType};
use serenity::model::guild::Member;
use serenity::model::id::UserId;
use serenity::model::prelude::ChannelId;
use serenity::model::prelude::Guild;
use serenity::model::Permissions;
use serenity::prelude::Context;
use serenity::utils::MessageBuilder;

use crate::data::{BotConfig, GameState, GlobalData, MessageSource, PlayerData};
use std::time::UNIX_EPOCH;

pub async fn send_msg_to_player_channels(
    ctx: &Context,
    guild: &Guild,
    global_data: &GlobalData,
    msg_source: MessageSource,
    msg: &str,
    pin: bool,
) {
    for player_data in &global_data.game_state.player_data {
        if let MessageSource::Player(channel_id) = msg_source {
            if channel_id == player_data.channel {
                continue;
            }
        }

        let channel = guild
            .channels
            .get(&ChannelId::from(player_data.channel))
            .unwrap();

        let msg = channel
            .send_message(&ctx.http, |m| m.content(&msg))
            .await
            .unwrap();

        if pin {
            // pin system messages
            msg.pin(&ctx.http).await.unwrap();
        }
    }

    let host_channel = guild
        .channels
        .get(&ChannelId::from(global_data.cfg.host_channel))
        .unwrap();

    let source = match msg_source {
        MessageSource::Player(channel_id) => {
            let discord_id = global_data
                .game_state
                .get_player_from_channel(channel_id)
                .unwrap()
                .discord_id;
            let name = guild
                .members
                .get(&UserId::from(discord_id))
                .unwrap()
                .display_name();

            name.to_string()
        }
        MessageSource::Host => "Host".to_string(),
        MessageSource::Automated => "Automated".to_string(),
    };

    host_channel
        .send_message(&ctx.http, |m| m.content(format!("({}): {}", source, msg)))
        .await
        .unwrap();
}

pub fn save_game_state(global_data: &GlobalData) -> std::io::Result<()> {
    let s = toml::to_string_pretty(&global_data.game_state).unwrap();

    let mut file = File::create(global_data.cfg.get_game_state_path())?;

    file.write_all(s.as_bytes())
}

pub fn get_game_state(global_data: &mut GlobalData) -> std::io::Result<()> {
    let mut file = File::open(global_data.cfg.get_game_state_path())?;

    let mut data = String::new();

    file.read_to_string(&mut data)?;

    global_data.game_state = toml::from_str(&data).unwrap();

    Ok(())
}

pub fn clear_game_state(global_data: &mut GlobalData) -> std::io::Result<()> {
    global_data.game_state.clear();

    let state_path = global_data.cfg.get_game_state_path();
    if state_path.exists() {
        std::fs::remove_file(global_data.cfg.get_game_state_path())?;
    }

    Ok(())
}

pub fn generate_codename(config: &BotConfig) -> String {
    let mut rng = rand::thread_rng();

    let occupation = &config.occupation[rng.gen_range(0..config.occupation.len())];
    let adj = &config.adjective[rng.gen_range(0..config.adjective.len())];

    format!("{} {}", adj, occupation)
}

pub async fn add_user_to_game(
    ctx: &Context,
    guild: &Guild,
    global_data: &mut GlobalData,
    discord_user: &Member,
) -> CommandResult {
    let mut codename = generate_codename(&global_data.cfg);

    while global_data.game_state.codename_exists(&codename) {
        codename = generate_codename(&global_data.cfg);
    }

    let channel = guild
        .create_channel(&ctx.http, |c| {
            c.category(&ChannelId::from(global_data.cfg.category))
                .name(format!("{}'s Channel", discord_user.display_name()))
        })
        .await?;

    let allow =
        Permissions::SEND_MESSAGES | Permissions::READ_MESSAGE_HISTORY | Permissions::READ_MESSAGES;

    let overwrite = PermissionOverwrite {
        allow,
        deny: Default::default(),
        kind: PermissionOverwriteType::Member(discord_user.user.id),
    };

    channel.create_permission(&ctx.http, &overwrite).await?;

    let msg = channel.send_message(&ctx.http, |m| {
        m.content(MessageBuilder::new()
            .push("Welcome ")
            .mention(discord_user)
            .push_line(" to your WOxlf Terminal. You may use this terminal to communicate to other subjects.")
            .push_line("You will also use this terminal for choosing one of your fellow subjects for termination.")
            .push_line("Happy testing :)")
            .push_line("")
            .push("SUBJECT CODENAME: ")
            .push_line(&codename)
            .push(print_game_status(&global_data.game_state))
        )
    }).await?;

    channel.pin(&ctx.http, msg.id).await?;

    let player_data = PlayerData {
        channel: channel.id.0,
        discord_id: discord_user.user.id.0,
        vote_target: None,
        codename,
    };

    global_data.game_state.player_data.push(player_data);

    Ok(())
}

pub fn build_system_message(msg: &str) -> String {
    MessageBuilder::new()
        .push_bold_line("\\*\\*IMPORTANT wOxlf SYSTEM MESSAGE\\*\\*")
        .push_line("")
        .push_line(msg)
        .push_line("")
        .push_bold_line("\\*\\*END OF SYSTEM MESSAGE\\*\\*")
        .build()
}

pub fn print_game_status(game_state: &GameState) -> String {
    MessageBuilder::new()
        .push_line(format!(
            "CURRENT EXPERIMENT PHASE: {} {}",
            game_state.current_phase, game_state.phase_number
        ))
        .push_line(format!(
            "PHASE END TIME: {}",
            game_state.get_phase_end_time()
        ))
        .push_line(format!("PHASE ENDING {}", game_state.get_phase_countdown()))
        .build()
}

pub fn get_phase_end_timestamp(hours: u64) -> u64 {
    let end_time = std::time::SystemTime::now() + std::time::Duration::from_secs(hours * 60 * 60);
    end_time.duration_since(UNIX_EPOCH).unwrap().as_secs()
}