feat: graceful shutdown, try making join and leave work (but some bug fixes are still needed)

src/command/leave.rs

@@ -1,12 +1,23 @@
-use std::sync::LazyLock;
-
-use twilight_model::application::{
-    command::{Command, CommandType},
-    interaction::Interaction,
-};
-use twilight_util::builder::command::CommandBuilder;
-
+use crate::VCs;
 use crate::command::State;
+use snafu::{OptionExt, Snafu};
+use std::sync::LazyLock;
+use twilight_model::channel::message::{Embed, MessageFlags};
+use twilight_model::http::interaction::{InteractionResponse, InteractionResponseType};
+use twilight_model::id::marker::UserMarker;
+use twilight_model::{
+    application::{
+        command::{Command, CommandType},
+        interaction::Interaction,
+    },
+    id::{
+        Id,
+        marker::{ChannelMarker, GuildMarker},
+    },
+};
+use twilight_util::builder::InteractionResponseDataBuilder;
+use twilight_util::builder::command::CommandBuilder;
+use twilight_util::builder::embed::EmbedBuilder;
 
 const NAME: &str = "leave";
 const DESCRIPTION: &str = "The bot will leave the VC it's in (so it won't record anyone anymore)";
@@ -18,7 +29,96 @@ pub static COMMAND: LazyLock<Command> = LazyLock::new(|| {
         .build()
 });
 
+#[derive(Debug, Snafu)]
+pub enum GetGuildAndVoiceChannelIdError {
+    /// this command was not used inside a guild (Discord server)
+    NotInGuild,
+
+    /// there are no voice chats in this guild
+    NoVCsInGuild,
+
+    /// the bot is not in a voice chat in this guild
+    BotNotInVC,
+}
+
+#[tracing::instrument]
+pub fn get_guild_and_voice_channel_id(
+    bot_user_id: Id<UserMarker>,
+    interaction: &Interaction,
+    vcs: &VCs,
+) -> Result<(Id<GuildMarker>, Id<ChannelMarker>), GetGuildAndVoiceChannelIdError> {
+    let guild_id = interaction.guild_id.context(NotInGuildSnafu)?;
+
+    let guild_vcs = vcs.get(&guild_id).context(NoVCsInGuildSnafu)?;
+
+    let &voice_channel_id = guild_vcs
+        .get_left_for(&bot_user_id)
+        .context(BotNotInVCSnafu)?;
+
+    Ok((guild_id, voice_channel_id))
+}
+
+fn get_guild_and_vc_error_to_embed(error: GetGuildAndVoiceChannelIdError) -> Embed {
+    match error {
+        GetGuildAndVoiceChannelIdError::NotInGuild => {
+            EmbedBuilder::new().title("Use this in a server").description("This bot can't tell which VC to leave if the command is used outside of a server (you might've used it in a DM?).").validate().unwrap().build()
+        }
+        GetGuildAndVoiceChannelIdError::NoVCsInGuild => {
+            EmbedBuilder::new().title("No VCs in this server").description("This bot can't leave VC because there aren't any in this server right now (therefore the bot must not be in any).").validate().unwrap().build()
+        },
+        GetGuildAndVoiceChannelIdError::BotNotInVC => {
+            EmbedBuilder::new().title("Not in a VC").description("This bot can't leave VC if it isn't in one in this server.").validate().unwrap().build()
+        },
+    }
+}
+
 #[tracing::instrument]
 pub async fn handle(state: State, interaction: Interaction) {
-    todo!();
+    let (guild_id, voice_channel_id) =
+        match get_guild_and_voice_channel_id(state.discord_user_id, &interaction, &state.vcs) {
+            Ok((guild_id, voice_channel_id)) => (guild_id, voice_channel_id),
+            Err(error) => {
+                state
+                    .discord_client
+                    .interaction(state.discord_application_id)
+                    .create_response(
+                        interaction.id,
+                        &interaction.token,
+                        &InteractionResponse {
+                            kind: InteractionResponseType::ChannelMessageWithSource,
+                            data: Some(
+                                InteractionResponseDataBuilder::new()
+                                    .embeds([get_guild_and_vc_error_to_embed(error)])
+                                    .flags(MessageFlags::EPHEMERAL)
+                                    .build(),
+                            ),
+                        },
+                    )
+                    .await
+                    .expect("TODO");
+
+                return;
+            }
+        };
+
+    state.songbird.leave(guild_id).await.expect("TODO");
+
+    tracing::error!("TODO: successfully left the call");
+
+    let channel_mention = format!("<#{voice_channel_id}>");
+
+    state
+        .discord_client
+        .interaction(state.discord_application_id)
+        .update_response(&interaction.token)
+        .embeds(Some(&[EmbedBuilder::new()
+            .title("Left VC")
+            .description(format!(
+                "This bot left {channel_mention} (and is thereby unable to record anymore)."
+            ))
+            .validate()
+            .unwrap()
+            .build()]))
+        .await
+        .expect("TODO");
 }