feat(prs-create) find commits and create events

 - identify commits
 - create pull request event
 - create patch events

3 files changed, 394 insertions, 0 deletions

diff --git a/src/sub_commands/mod.rs b/src/sub_commands/mod.rs
index 320cbbb..3c3da1d 100644
--- a/src/sub_commands/mod.rs
+++ b/src/sub_commands/mod.rs
@@ -1 +1,2 @@
 pub mod login;
+pub mod prs;
diff --git a/src/sub_commands/prs/create.rs b/src/sub_commands/prs/create.rs
new file mode 100644
index 0000000..dd32c65
--- /dev/null
+++ b/src/sub_commands/prs/create.rs
@@ -0,0 +1,371 @@
+use anyhow::{bail, Context, Result};
+use nostr::{prelude::sha1::Hash as Sha1Hash, EventBuilder, Marker, Tag, TagKind};
+
+use crate::{
+    cli_interactor::{Interactor, InteractorPrompt, PromptConfirmParms, PromptInputParms},
+    git::{Repo, RepoActions},
+    login, Cli,
+};
+
+#[derive(Debug, clap::Args)]
+pub struct SubCommandArgs {
+    #[clap(short, long)]
+    /// title of pull request (defaults to first line of first commit)
+    title: Option<String>,
+    #[clap(short, long)]
+    /// optional description
+    description: Option<String>,
+    #[clap(long)]
+    /// branch to get changes from (defaults to head)
+    from_branch: Option<String>,
+    #[clap(long)]
+    /// destination branch (defaults to main or master)
+    to_branch: Option<String>,
+}
+
+pub fn launch(
+    cli_args: &Cli,
+    _pr_args: &super::SubCommandArgs,
+    args: &SubCommandArgs,
+) -> Result<()> {
+    let git_repo = Repo::discover().context("cannot find a git repository")?;
+
+    let (from_branch, to_branch, ahead, behind) =
+        identify_ahead_behind(&git_repo, &args.from_branch, &args.to_branch)?;
+
+    if ahead.is_empty() {
+        bail!(format!(
+            "'{from_branch}' is 0 commits ahead of '{to_branch}' so no patches were created"
+        ));
+    }
+
+    if behind.is_empty() {
+        println!(
+            "creating patch for {} commits from '{from_branch}' that can be merged into '{to_branch}'",
+            ahead.len(),
+        );
+    } else {
+        if !Interactor::default().confirm(
+            PromptConfirmParms::default()
+                .with_prompt(
+                    format!(
+                        "'{from_branch}' is {} commits behind '{to_branch}' and {} ahead. Consider rebasing before sending patches. Proceed anyway?",
+                        behind.len(),
+                        ahead.len(),
+                    )
+                )
+                .with_default(false)
+        ).context("failed to get confirmation response from interactor confirm")? {
+            bail!("aborting so branch can be rebased");
+        }
+        println!(
+            "creating patch for {} commit{} from '{from_branch}' that {} {} behind '{to_branch}'",
+            ahead.len(),
+            if ahead.len() > 1 { "s" } else { "" },
+            if ahead.len() > 1 { "are" } else { "is" },
+            behind.len(),
+        );
+    }
+
+    let title = match &args.title {
+        Some(t) => t.clone(),
+        None => Interactor::default().input(PromptInputParms::default().with_prompt("title"))?,
+    };
+
+    let description = match &args.description {
+        Some(t) => t.clone(),
+        None => Interactor::default()
+            .input(PromptInputParms::default().with_prompt("description (Optional)"))?,
+    };
+
+    let root_commit = git_repo
+        .get_root_commit(to_branch.as_str())
+        .context("failed to get root commit of the repository")?;
+    // create PR event
+
+    let keys = login::launch(&cli_args.nsec, &cli_args.password)?;
+
+    let pr_event = EventBuilder::new(
+        nostr::event::Kind::Custom(318),
+        format!("{title}\r\n\r\n{description}"),
+        &[Tag::Hashtag(format!("r-{root_commit}"))],
+        // TODO: suggested branch name
+        // Tag::Generic(
+        //     TagKind::Custom("suggested-branch-name".to_string()),
+        //     vec![],
+        // ),
+        // TODO: add Repo event as root
+        // TODO: people tag maintainers
+        // TODO: add relay tags
+    )
+    .to_event(&keys)
+    .context("failed to create pr event")?;
+
+    let mut patch_events = vec![];
+    for commit in &ahead {
+        let commit_parent = git_repo
+            .get_commit_parent(commit)
+            .context("failed to create patch event")?;
+        patch_events.push(
+            EventBuilder::new(
+                nostr::event::Kind::Custom(317),
+                git_repo
+                    .make_patch_from_commit(commit)
+                    .context(format!("cannot make patch for commit {commit}"))?,
+                &[
+                    Tag::Hashtag(format!("r-{root_commit}")),
+                    Tag::Hashtag(commit.to_string()),
+                    Tag::Hashtag(commit_parent.to_string()),
+                    Tag::Event(
+                        pr_event.id,
+                        None, // TODO: add relay
+                        Some(Marker::Root),
+                    ),
+                    Tag::Generic(
+                        TagKind::Custom("commit".to_string()),
+                        vec![commit.to_string()],
+                    ),
+                    Tag::Generic(
+                        TagKind::Custom("parent-commit".to_string()),
+                        vec![commit_parent.to_string()],
+                    ),
+                    // TODO: add Repo event tags
+                    // TODO: people tag maintainers
+                    // TODO: add relay tags
+                ],
+            )
+            .to_event(&keys),
+        );
+    }
+
+    // TODO check if there is already a similarly named PR
+    // TODO connect to relays and post
+
+    Ok(())
+}
+
+// TODO
+// - find profile
+// - file relays
+// - find repo events
+// -
+
+/**
+ * returns `(from_branch,to_branch,ahead,behind)`
+ */
+fn identify_ahead_behind(
+    git_repo: &Repo,
+    from_branch: &Option<String>,
+    to_branch: &Option<String>,
+) -> Result<(String, String, Vec<Sha1Hash>, Vec<Sha1Hash>)> {
+    let (from_branch, from_tip) = match from_branch {
+        Some(name) => (
+            name.to_string(),
+            git_repo
+                .get_tip_of_local_branch(name)
+                .context(format!("cannot find from_branch '{name}'"))?,
+        ),
+        None => (
+            "head".to_string(),
+            git_repo
+                .get_head_commit()
+                .context("failed to get head commit")
+                .context(
+                    "checkout a commit or specify a from_branch. head does not reveal a commit",
+                )?,
+        ),
+    };
+
+    let (to_branch, to_tip) = match to_branch {
+        Some(name) => (
+            name.to_string(),
+            git_repo
+                .get_tip_of_local_branch(name)
+                .context(format!("cannot find to_branch '{name}'"))?,
+        ),
+        None => {
+            let (name, commit) = git_repo
+                .get_main_or_master_branch()
+                .context("a destination branch (to_branch) is not specified and the defaults (main or master) do not exist")?;
+            (name.to_string(), commit)
+        }
+    };
+
+    match git_repo.get_commits_ahead_behind(&to_tip, &from_tip) {
+        Err(e) => {
+            if e.to_string().contains("is not an ancestor of") {
+                return Err(e).context(format!(
+                    "'{from_branch}' is not branched from '{to_branch}'"
+                ));
+            }
+            Err(e).context(format!(
+                "failed to get commits ahead and behind from '{from_branch}' to '{to_branch}'"
+            ))
+        }
+        Ok((ahead, behind)) => Ok((from_branch, to_branch, ahead, behind)),
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use test_utils::git::GitTestRepo;
+
+    use super::*;
+    mod identify_ahead_behind {
+
+        use super::*;
+        use crate::git::oid_to_sha1;
+
+        #[test]
+        fn when_from_branch_doesnt_exist_return_error() -> Result<()> {
+            let test_repo = GitTestRepo::default();
+            let git_repo = Repo::from_path(&test_repo.dir)?;
+
+            test_repo.populate()?;
+            let branch_name = "doesnt_exist";
+            assert_eq!(
+                identify_ahead_behind(&git_repo, &Some(branch_name.to_string()), &None)
+                    .unwrap_err()
+                    .to_string(),
+                format!("cannot find from_branch '{}'", &branch_name),
+            );
+            Ok(())
+        }
+
+        #[test]
+        fn when_to_branch_doesnt_exist_return_error() -> Result<()> {
+            let test_repo = GitTestRepo::default();
+            let git_repo = Repo::from_path(&test_repo.dir)?;
+
+            test_repo.populate()?;
+            let branch_name = "doesnt_exist";
+            assert_eq!(
+                identify_ahead_behind(&git_repo, &None, &Some(branch_name.to_string()))
+                    .unwrap_err()
+                    .to_string(),
+                format!("cannot find to_branch '{}'", &branch_name),
+            );
+            Ok(())
+        }
+
+        #[test]
+        fn when_to_branch_is_none_and_no_main_or_master_branch_return_error() -> Result<()> {
+            let test_repo = GitTestRepo::new("notmain")?;
+            let git_repo = Repo::from_path(&test_repo.dir)?;
+
+            test_repo.populate()?;
+
+            assert_eq!(
+                identify_ahead_behind(&git_repo, &None, &None)
+                    .unwrap_err()
+                    .to_string(),
+                "a destination branch (to_branch) is not specified and the defaults (main or master) do not exist",
+            );
+            Ok(())
+        }
+
+        #[test]
+        fn when_from_branch_is_none_return_as_head() -> Result<()> {
+            let test_repo = GitTestRepo::default();
+            let git_repo = Repo::from_path(&test_repo.dir)?;
+
+            test_repo.populate()?;
+            // create feature branch with 1 commit ahead
+            test_repo.create_branch("feature")?;
+            test_repo.checkout("feature")?;
+            std::fs::write(test_repo.dir.join("t3.md"), "some content")?;
+            let head_oid = test_repo.stage_and_commit("add t3.md")?;
+
+            // make feature branch 1 commit behind
+            test_repo.checkout("main")?;
+            std::fs::write(test_repo.dir.join("t4.md"), "some content")?;
+            let main_oid = test_repo.stage_and_commit("add t4.md")?;
+            // checkout feature
+            test_repo.checkout("feature")?;
+
+            let (from_branch, to_branch, ahead, behind) =
+                identify_ahead_behind(&git_repo, &None, &None)?;
+
+            assert_eq!(from_branch, "head");
+            assert_eq!(ahead, vec![oid_to_sha1(&head_oid)]);
+            assert_eq!(to_branch, "main");
+            assert_eq!(behind, vec![oid_to_sha1(&main_oid)]);
+            Ok(())
+        }
+
+        #[test]
+        fn when_from_branch_is_not_head_return_as_from_branch() -> Result<()> {
+            let test_repo = GitTestRepo::default();
+            let git_repo = Repo::from_path(&test_repo.dir)?;
+
+            test_repo.populate()?;
+            // create feature branch with 1 commit ahead
+            test_repo.create_branch("feature")?;
+            test_repo.checkout("feature")?;
+            std::fs::write(test_repo.dir.join("t3.md"), "some content")?;
+            let head_oid = test_repo.stage_and_commit("add t3.md")?;
+
+            // make feature branch 1 commit behind
+            test_repo.checkout("main")?;
+            std::fs::write(test_repo.dir.join("t4.md"), "some content")?;
+            let main_oid = test_repo.stage_and_commit("add t4.md")?;
+
+            let (from_branch, to_branch, ahead, behind) =
+                identify_ahead_behind(&git_repo, &Some("feature".to_string()), &None)?;
+
+            assert_eq!(from_branch, "feature");
+            assert_eq!(ahead, vec![oid_to_sha1(&head_oid)]);
+            assert_eq!(to_branch, "main");
+            assert_eq!(behind, vec![oid_to_sha1(&main_oid)]);
+            Ok(())
+        }
+
+        #[test]
+        fn when_to_branch_is_not_main_return_as_to_branch() -> Result<()> {
+            let test_repo = GitTestRepo::default();
+            let git_repo = Repo::from_path(&test_repo.dir)?;
+
+            test_repo.populate()?;
+            // create dev branch with 1 commit ahead
+            test_repo.create_branch("dev")?;
+            test_repo.checkout("dev")?;
+            std::fs::write(test_repo.dir.join("t3.md"), "some content")?;
+            let dev_oid_first = test_repo.stage_and_commit("add t3.md")?;
+
+            // create feature branch with 1 commit ahead of dev
+            test_repo.create_branch("feature")?;
+            test_repo.checkout("feature")?;
+            std::fs::write(test_repo.dir.join("t4.md"), "some content")?;
+            let feature_oid = test_repo.stage_and_commit("add t4.md")?;
+
+            // make feature branch 1 behind
+            test_repo.checkout("dev")?;
+            std::fs::write(test_repo.dir.join("t3.md"), "some content")?;
+            let dev_oid = test_repo.stage_and_commit("add t3.md")?;
+
+            let (from_branch, to_branch, ahead, behind) = identify_ahead_behind(
+                &git_repo,
+                &Some("feature".to_string()),
+                &Some("dev".to_string()),
+            )?;
+
+            assert_eq!(from_branch, "feature");
+            assert_eq!(ahead, vec![oid_to_sha1(&feature_oid)]);
+            assert_eq!(to_branch, "dev");
+            assert_eq!(behind, vec![oid_to_sha1(&dev_oid)]);
+
+            let (from_branch, to_branch, ahead, behind) =
+                identify_ahead_behind(&git_repo, &Some("feature".to_string()), &None)?;
+
+            assert_eq!(from_branch, "feature");
+            assert_eq!(
+                ahead,
+                vec![oid_to_sha1(&feature_oid), oid_to_sha1(&dev_oid_first)]
+            );
+            assert_eq!(to_branch, "main");
+            assert_eq!(behind, vec![]);
+
+            Ok(())
+        }
+    }
+}
diff --git a/src/sub_commands/prs/mod.rs b/src/sub_commands/prs/mod.rs
new file mode 100644
index 0000000..c316e73
--- /dev/null
+++ b/src/sub_commands/prs/mod.rs
@@ -0,0 +1,22 @@
+use anyhow::Result;
+use clap::Subcommand;
+
+use crate::Cli;
+pub mod create;
+
+#[derive(clap::Parser)]
+pub struct SubCommandArgs {
+    #[command(subcommand)]
+    pub prs_command: Commands,
+}
+
+#[derive(Debug, Subcommand)]
+pub enum Commands {
+    Create(create::SubCommandArgs),
+}
+
+pub fn launch(cli_args: &Cli, pr_args: &SubCommandArgs) -> Result<()> {
+    match &pr_args.prs_command {
+        Commands::Create(args) => create::launch(cli_args, pr_args, args),
+    }
+}