use serenity::all::{ChannelId, Context, Guild, GuildId, PartialGuild, UserId, VoiceState};
use std::collections::HashMap;

/// Request a guild by id, get it from cache
pub fn request_guild(ctx: &Context, guild_id: &GuildId) -> Guild {
    match guild_id.to_guild_cached(&ctx.cache) {
        Some(guild) => guild.clone(),
        None => {
            panic!("Cannot get guild with id {:?}!", guild_id);
        }
    }
}

/// Request a guild by id, get it from Discord, not from cache, this is a partial guild
#[allow(dead_code)]
pub async fn request_partial_guild(ctx: &Context, guild_id: &GuildId) -> PartialGuild {
    match ctx.http.get_guild(*guild_id).await {
        Ok(guild) => guild,
        Err(error) => {
            panic!("error whilest getting guild from Discord {}", error);
        }
    }
}

/// Get the voice channel id of a user
pub async fn get_vc_id(ctx: &Context, guild_id: &GuildId, user_id: &UserId) -> Option<ChannelId> {
    let guild = request_guild(ctx, guild_id);
    guild
        .voice_states
        .get(user_id)
        .and_then(|voice_state| voice_state.channel_id)
}

/// Check if the bot is connected to a voice channel
pub async fn is_self_connected_to_vc(ctx: &Context, guild_id: &GuildId) -> bool {
    get_self_vc_id(ctx, guild_id).await.is_some()
}

/// Check if a user is connected to a voice channel
pub async fn is_user_connected_to_vc(ctx: &Context, guild_id: &GuildId, user_id: &UserId) -> bool {
    get_vc_id(ctx, guild_id, user_id).await.is_some()
}

/// Get the voice channel id of the bot
pub async fn get_self_vc_id(ctx: &Context, guild_id: &GuildId) -> Option<ChannelId> {
    let user_id = ctx.cache.current_user().id;

    get_vc_id(ctx, guild_id, &user_id).await
}

/// Get all voice states of a guild
pub async fn get_voice_states(ctx: &Context, guild_id: &GuildId) -> HashMap<UserId, VoiceState> {
    let guild = request_guild(ctx, guild_id);
    guild.voice_states.clone()
}

/// Get the amount of members in a voice channel
pub async fn get_amount_of_members_in_vc(
    ctx: &Context,
    guild_id: &GuildId,
    channel_id: &ChannelId,
) -> usize {
    let voice_states = get_voice_states(ctx, guild_id).await;
    let amount = voice_states
        .iter()
        .filter(|(_, voice_state)| voice_state.channel_id == Some(*channel_id))
        .count();
    amount
}