crosspost command

src/commands/crosspost.rs

@@ -0,0 +1,51 @@
+use crate::util::debug_say;
+use lazy_static::lazy_static;
+use log::error;
+use regex::Regex;
+use serenity::framework::standard::CommandError;
+use serenity::framework::standard::{macros::command, Args, CommandResult};
+use serenity::model::{channel::Message, id::ChannelId};
+use serenity::prelude::Context;
+use std::collections::HashMap;
+use std::str::FromStr;
+
+lazy_static! {
+    static ref CHANNEL_REGEX: Regex = Regex::new(r"<#\d+>").unwrap();
+}
+
+#[command]
+async fn crosspost(ctx: &Context, msg: &Message, mut args: Args) -> CommandResult {
+    let guild_id = msg.guild_id;
+    let guild_id = match guild_id {
+        Some(guild_id) => guild_id,
+        None => return Err(CommandError::from(String::from("Not in guild"))),
+    };
+    let mut avail_channels: HashMap<ChannelId, _> = guild_id.channels(ctx).await?;
+    avail_channels.remove(&msg.channel_id); // Don't crosspost to current channel.
+    let mut channels = vec![];
+    while args.current().is_some() {
+        let arg = args.current().unwrap();
+        if CHANNEL_REGEX.is_match(&arg) {
+            match avail_channels.get(&ChannelId::from_str(arg.as_ref())?) {
+                Some(channel) => channels.push(channel),
+                None => {}
+            }
+            args.advance();
+        } else {
+            // Stop early if we stop getting channel ids
+            break;
+        }
+    }
+
+    let rest = format!(
+        "Crossposted from <#{}> by {}:\n{}",
+        msg.channel_id,
+        msg.author,
+        args.rest()
+    );
+    for channel in channels {
+        channel.say(ctx, &rest).await?;
+    }
+
+    Ok(())
+}

src/commands/mod.rs

@@ -1,13 +1,15 @@
 use crate::commands::{
-    clap::CLAP_COMMAND, cube::CUBE_COMMAND, heck::HECK_COMMAND, source::SOURCE_COMMAND,
+    clap::CLAP_COMMAND, crosspost::CROSSPOST_COMMAND, cube::CUBE_COMMAND, heck::HECK_COMMAND,
+    source::SOURCE_COMMAND,
 };
 use serenity::framework::standard::macros::group;
 
 mod clap;
+mod crosspost;
 mod cube;
 mod heck;
 mod source;
 
 #[group]
-#[commands(heck, clap, cube, source)]
+#[commands(heck, clap, cube, source, crosspost)]
 pub(crate) struct General;