feat: Generate Northstar release notes (#277)

* feat: Allow selecting project
to generate release notes for

* fix: Add missing TypeScript bindings

* feat: Pass project to backend on tag compare

* fix: Check for unsupported project

* feat: Allow fetching tags from Northstar repo

* fix: Formatting and fixing typo

* feat: Copy over Northstar release note generation
from previous PR

* refactor: Use Tag struct instead of string
Allows for extendability in the future

* fix: Use proper user-agent for web request

* fix: Remove debug log prints

* refactor: Use separete function for FlightCore
release note generation

One function for each FlightCore and Northstar

* feat: Make CommitAuthor optional
to deal with rebase commits that don't have a PR linked

* fix: Address clippy issues

* fix: Remove debug prints

* docs: Add comments

* refactor: Move import to top of source file

2 files changed, 134 insertions, 4 deletions

diff --git a/src-tauri/src/constants.rs b/src-tauri/src/constants.rs
index 8c88df1e..6e294e55 100644
--- a/src-tauri/src/constants.rs
+++ b/src-tauri/src/constants.rs
@@ -48,3 +48,6 @@ pub const REFRESH_DELAY: Duration = Duration::from_secs(5 * 60);
 
 // Flightcore repo name and org name on GitHub
 pub const FLIGHTCORE_REPO_NAME: &str = "R2NorthstarTools/FlightCore";
+
+// Northstar release repo name and org name on GitHub
+pub const NORTHSTAR_RELEASE_REPO_NAME: &str = "R2Northstar/Northstar";
diff --git a/src-tauri/src/github/mod.rs b/src-tauri/src/github/mod.rs
index b336ab5c..12729de2 100644
--- a/src-tauri/src/github/mod.rs
+++ b/src-tauri/src/github/mod.rs
@@ -1,7 +1,10 @@
 pub mod pull_requests;
 pub mod release_notes;
 
-use app::constants::{APP_USER_AGENT, FLIGHTCORE_REPO_NAME, SECTION_ORDER};
+use app::constants::{
+    APP_USER_AGENT, FLIGHTCORE_REPO_NAME, NORTHSTAR_RELEASE_REPO_NAME, SECTION_ORDER,
+};
+use regex::Regex;
 use serde::{Deserialize, Serialize};
 use std::collections::HashMap;
 use ts_rs::TS;
@@ -12,6 +15,13 @@ pub struct Tag {
     name: String,
 }
 
+#[derive(Serialize, Deserialize, Debug, Clone, PartialEq, TS)]
+#[ts(export)]
+pub enum Project {
+    FlightCore,
+    Northstar,
+}
+
 /// Wrapper type needed for frontend
 #[derive(Serialize, Deserialize, Debug, Clone, TS)]
 #[ts(export)]
@@ -24,6 +34,7 @@ pub struct TagWrapper {
 struct CommitInfo {
     sha: String,
     commit: Commit,
+    author: Option<CommitAuthor>,
 }
 
 #[derive(Debug, Deserialize)]
@@ -32,13 +43,18 @@ struct Commit {
 }
 
 #[derive(Debug, Deserialize)]
+struct CommitAuthor {
+    login: String,
+}
+
+#[derive(Debug, Deserialize)]
 struct Comparison {
     commits: Vec<CommitInfo>,
 }
 
 /// Get a list of tags on the FlightCore repo
 #[tauri::command]
-pub fn get_list_of_tags() -> Result<Vec<TagWrapper>, String> {
+pub fn get_list_of_tags(project: Project) -> Result<Vec<TagWrapper>, String> {
     // Set the repository name.
 
     // Create a `reqwest` client with a user agent.
@@ -47,8 +63,14 @@ pub fn get_list_of_tags() -> Result<Vec<TagWrapper>, String> {
         .build()
         .unwrap();
 
+    // Switch repo to fetch from based on project
+    let repo_name = match project {
+        Project::FlightCore => FLIGHTCORE_REPO_NAME,
+        Project::Northstar => NORTHSTAR_RELEASE_REPO_NAME,
+    };
+
     // Fetch the list of tags for the repository as a `Vec<Tag>`.
-    let tags_url = format!("https://api.github.com/repos/{}/tags", FLIGHTCORE_REPO_NAME);
+    let tags_url = format!("https://api.github.com/repos/{}/tags", repo_name);
     let tags: Vec<Tag> = client.get(tags_url).send().unwrap().json().unwrap();
 
     // Map each `Tag` element to a `TagWrapper` element with the desired label and `Tag` value.
@@ -65,7 +87,14 @@ pub fn get_list_of_tags() -> Result<Vec<TagWrapper>, String> {
 
 /// Use GitHub API to compare two tags of the same repo against each other and get the resulting changes
 #[tauri::command]
-pub fn compare_tags(first_tag: Tag, second_tag: Tag) -> Result<String, String> {
+pub fn compare_tags(project: Project, first_tag: Tag, second_tag: Tag) -> Result<String, String> {
+    match project {
+        Project::FlightCore => compare_tags_flightcore(first_tag, second_tag),
+        Project::Northstar => compare_tags_northstar(first_tag, second_tag),
+    }
+}
+
+pub fn compare_tags_flightcore(first_tag: Tag, second_tag: Tag) -> Result<String, String> {
     // Fetch the list of commits between the two tags.
 
     // Create a `reqwest` client with a user agent.
@@ -181,3 +210,101 @@ fn group_commits_by_type(commits: Vec<String>) -> HashMap<String, Vec<String>> {
 
     grouped_commits
 }
+
+/// Compares two tags on Northstar repo and generates release notes over the diff in tags
+/// over the 3 major repos (Northstar, NorthstarLauncher, NorthstarMods)
+pub fn compare_tags_northstar(first_tag: Tag, second_tag: Tag) -> Result<String, String> {
+    // Fetch the list of commits between the two tags.
+
+    // Create a `reqwest` client with a user agent.
+    let client = reqwest::blocking::Client::builder()
+        .user_agent(APP_USER_AGENT)
+        .build()
+        .unwrap();
+
+    let repos = [
+        "R2Northstar/Northstar",
+        "R2Northstar/NorthstarLauncher",
+        "R2Northstar/NorthstarMods",
+    ];
+
+    let mut full_patch_notes = "".to_string();
+    let mut authors_set = std::collections::HashSet::new();
+
+    for repo in repos {
+        full_patch_notes += &format!("{}\n\n", repo);
+
+        let mut patch_notes: Vec<String> = [].to_vec();
+        println!("{}", repo);
+        // let repo = "R2Northstar/NorthstarLauncher";
+        let comparison_url = format!(
+            "https://api.github.com/repos/{}/compare/{}...{}",
+            repo, first_tag.name, second_tag.name
+        );
+
+        log::info!("Compare URL: {}", comparison_url.clone());
+        let comparison: Comparison = client.get(&comparison_url).send().unwrap().json().unwrap();
+        let commits = comparison.commits;
+
+        // Display the list of commits.
+        println!(
+            "Commits between {} and {}:",
+            first_tag.name, second_tag.name
+        );
+
+        //
+        for commit in commits {
+            println!(
+                "  * {} : {}",
+                commit.sha,
+                turn_pr_number_into_link(commit.commit.message.split('\n').next().unwrap(), repo)
+            );
+            patch_notes.push(turn_pr_number_into_link(
+                commit.commit.message.split('\n').next().unwrap(),
+                repo,
+            ));
+
+            // Store authors in set
+            if commit.author.is_some() {
+                authors_set.insert(commit.author.unwrap().login);
+            }
+        }
+
+        full_patch_notes += &patch_notes.join("\n");
+        full_patch_notes += "\n\n\n";
+    }
+
+    // Convert the set to a sorted vector.
+    let mut sorted_vec: Vec<String> = authors_set.into_iter().collect();
+    sorted_vec.sort();
+
+    // Define a string to prepend to each element.
+    let prefix = "@";
+
+    // Create a new list with the prefix prepended to each element.
+    let prefixed_list: Vec<String> = sorted_vec.iter().map(|s| prefix.to_owned() + s).collect();
+
+    full_patch_notes += "**Contributors:**\n";
+    full_patch_notes += &prefixed_list.join(" ");
+
+    Ok(full_patch_notes.to_string())
+}
+
+/// Takes the commit title and repo slug and formats it as
+/// `[commit title(SHORTENED_REPO#NUMBER)](LINK)`
+fn turn_pr_number_into_link(input: &str, repo: &str) -> String {
+    // Extract `Mods/Launcher` from repo title
+    let last_line = repo
+        .split('/')
+        .rev()
+        .next()
+        .unwrap()
+        .trim_start_matches("Northstar");
+    // Extract PR number
+    let re = Regex::new(r"#(\d+)").unwrap();
+
+    // Generate pull request link
+    let pull_link = format!("https://github.com/{}/pull/", repo);
+    re.replace_all(input, format!("[{}#$1]({}$1)", last_line, pull_link))
+        .to_string()
+}