use libgit2 to track PRs (#10)v0.2.0

* nix: don't depend on registry for nixpkgs input

* use libgit2 to track PRs

* nix: don't use ci devShell as defaul

* crates: bump serenity from `9ad74d4` to `0.12.2

* nix: fix cross compiled builds

* crates: split more from client

* bot-jobs: update remote refs more efficiently

* git-tracker: account for HEAD commits

* bot-config: use nixpkgs branches from environment

* bot-commands: don't display branches prs haven't landed in

* git-tracker: return false when commits aren't found

this is annoying as a hard error since it turns out github will report
garbage merge commit SHAs for PRs that *haven't* been merged yet. yay

* bot: improve docs in some places

* bot-client: display invite link on start

* bot-http: add TeawieClientExt

* bot-commands: add /about

* docs: update readme todos

* nix: enable StateDirectory in module

* crates: bump to 0.2.0

4 files changed, 135 insertions, 0 deletions

diff --git a/crates/bot-http/src/github.rs b/crates/bot-http/src/github.rs
new file mode 100644
index 0000000..7822eb8
--- /dev/null
+++ b/crates/bot-http/src/github.rs
@@ -0,0 +1,35 @@
+use super::{ClientExt as _, Error};
+use crate::model::PullRequest;
+
+use std::future::Future;
+
+const GITHUB_API: &str = "https://api.github.com";
+
+pub trait ClientExt {
+	/// Get the commit that merged [`pr`] in [`repo_owner`]/[`repo_name`]
+	///
+	/// # Errors
+	///
+	/// Will return [`Err`] if the merge commit cannot be found
+	fn merge_commit_for(
+		&self,
+		repo_owner: &str,
+		repo_name: &str,
+		pr: u64,
+	) -> impl Future<Output = Result<Option<String>, Error>> + Send;
+}
+
+impl ClientExt for super::Client {
+	async fn merge_commit_for(
+		&self,
+		repo_owner: &str,
+		repo_name: &str,
+		pr: u64,
+	) -> Result<Option<String>, Error> {
+		let url = format!("{GITHUB_API}/repos/{repo_owner}/{repo_name}/pulls/{pr}");
+		let resp: PullRequest = self.get_json(&url).await?;
+		let merge_commit = resp.merge_commit_sha;
+
+		Ok(merge_commit)
+	}
+}
diff --git a/crates/bot-http/src/lib.rs b/crates/bot-http/src/lib.rs
new file mode 100644
index 0000000..ab32cd4
--- /dev/null
+++ b/crates/bot-http/src/lib.rs
@@ -0,0 +1,63 @@
+use std::future::Future;
+
+use log::trace;
+use serde::de::DeserializeOwned;
+
+mod github;
+mod model;
+mod teawie;
+
+pub use github::ClientExt as GithubClientExt;
+pub use teawie::ClientExt as TeawieClientExt;
+
+pub type Client = reqwest::Client;
+pub type Response = reqwest::Response;
+pub type Error = reqwest::Error;
+
+/// Fun trait for functions we use with [Client]
+pub trait ClientExt {
+	fn default() -> Self;
+	fn get_request(&self, url: &str) -> impl Future<Output = Result<Response, Error>> + Send;
+	fn get_json<T: DeserializeOwned>(
+		&self,
+		url: &str,
+	) -> impl Future<Output = Result<T, Error>> + Send;
+}
+
+impl ClientExt for Client {
+	/// Create the default [`Client`]
+	fn default() -> Self {
+		reqwest::Client::builder()
+			.user_agent(format!(
+				"nixpkgs-tracker-bot/{}",
+				option_env!("CARGO_PKG_VERSION").unwrap_or_else(|| "development")
+			))
+			.build()
+			.unwrap()
+	}
+
+	/// Perform a GET request to [`url`]
+	///
+	/// # Errors
+	///
+	/// Will return [`Err`] if the request fails
+	async fn get_request(&self, url: &str) -> Result<Response, Error> {
+		trace!("Making GET request to {url}");
+
+		let resp = self.get(url).send().await?;
+		resp.error_for_status_ref()?;
+
+		Ok(resp)
+	}
+
+	/// Perform a GET request to [`url`] and decode the json response
+	///
+	/// # Errors
+	///
+	/// Will return [`Err`] if the request fails or cannot be deserialized
+	async fn get_json<T: DeserializeOwned>(&self, url: &str) -> Result<T, Error> {
+		let resp = self.get_request(url).await?;
+		let json = resp.json().await?;
+		Ok(json)
+	}
+}
diff --git a/crates/bot-http/src/model.rs b/crates/bot-http/src/model.rs
new file mode 100644
index 0000000..afd4717
--- /dev/null
+++ b/crates/bot-http/src/model.rs
@@ -0,0 +1,13 @@
+use serde::Deserialize;
+
+/// Bad version of `/repos/{owner}/{repo}/pulls/{pull_number}` for Github's api
+#[derive(Clone, Debug, Deserialize)]
+pub struct PullRequest {
+	pub merge_commit_sha: Option<String>,
+}
+
+/// `/random_teawie` for the teawieAPI
+#[derive(Clone, Debug, Deserialize)]
+pub struct RandomTeawie {
+	pub url: Option<String>,
+}
diff --git a/crates/bot-http/src/teawie.rs b/crates/bot-http/src/teawie.rs
new file mode 100644
index 0000000..ea4f53e
--- /dev/null
+++ b/crates/bot-http/src/teawie.rs
@@ -0,0 +1,24 @@
+use super::{ClientExt as _, Error};
+use crate::model::RandomTeawie;
+
+use std::future::Future;
+
+const TEAWIE_API: &str = "https://api.getchoo.com";
+
+pub trait ClientExt {
+	/// Get a random teawie
+	///
+	/// # Errors
+	///
+	/// Will return [`Err`] if the request fails or the response cannot be deserialized
+	fn random_teawie(&self) -> impl Future<Output = Result<Option<String>, Error>> + Send;
+}
+
+impl ClientExt for super::Client {
+	async fn random_teawie(&self) -> Result<Option<String>, Error> {
+		let url = format!("{TEAWIE_API}/random_teawie");
+		let resp: RandomTeawie = self.get_json(&url).await?;
+
+		Ok(resp.url)
+	}
+}