From c98ca240a6ed236e560962eb8ffd366439f48756 Mon Sep 17 00:00:00 2001
From: extrawurst <mail@rusticorn.com>
Date: Fri, 15 Dec 2023 19:33:27 +0100
Subject: [PATCH] Add command to use ai to generate commit msg

---
 Cargo.lock                |  1 +
 Cargo.toml                |  1 +
 asyncgit/src/sync/diff.rs | 31 +++++++++++++++++++++++++++-
 asyncgit/src/sync/mod.rs  |  2 +-
 src/components/commit.rs  | 43 +++++++++++++++++++++++++++++++++++++++
 src/keys/key_list.rs      |  2 ++
 src/strings.rs            | 13 ++++++++++++
 7 files changed, 91 insertions(+), 2 deletions(-)

diff --git a/Cargo.lock b/Cargo.lock
index d922393a..70f37d1d 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -765,6 +765,7 @@ dependencies = [
  "filetreelist",
  "fuzzy-matcher",
  "gh-emoji",
+ "git2-summarize",
  "indexmap",
  "itertools",
  "log",
diff --git a/Cargo.toml b/Cargo.toml
index 43104819..bb70efea 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -16,6 +16,7 @@ keywords = ["git", "gui", "cli", "terminal", "ui"]
 [dependencies]
 anyhow = "1.0"
 asyncgit = { path = "./asyncgit", version = "0.24", default-features = false }
+git2-summarize = { path = "./git2-summarize", version = "0.1"}
 backtrace = "0.3"
 bitflags = "1.3"
 bugreport = "0.5"
diff --git a/asyncgit/src/sync/diff.rs b/asyncgit/src/sync/diff.rs
index f02e1be3..5f876914 100644
--- a/asyncgit/src/sync/diff.rs
+++ b/asyncgit/src/sync/diff.rs
@@ -9,7 +9,7 @@ use crate::{
 	error::Error,
 	error::Result,
 	hash,
-	sync::{get_stashes, repository::repo},
+	sync::{get_stashes, repository::repo, utils::bytes2string},
 };
 use easy_cast::Conv;
 use git2::{
@@ -398,6 +398,35 @@ fn raw_diff_to_file_diff(
 	Ok(res.into_inner())
 }
 
+///
+pub fn unified_stage_diff(repo_path: &RepoPath) -> Result<String> {
+	scope_time!("unified_stage_diff");
+
+	let repo = repo(repo_path)?;
+
+	let diff = get_diff_raw(&repo, "*", true, false, None)?;
+
+	let mut output = String::with_capacity(32);
+
+	diff.print(DiffFormat::Patch, |_delta, _hunk, line| {
+		let prefix = match line.origin_value() {
+			git2::DiffLineType::Addition => "+",
+			git2::DiffLineType::Deletion => "-",
+			_ => "",
+		};
+
+		output.push_str(&format!(
+			"{}{}",
+			prefix,
+			bytes2string(line.content()).unwrap()
+		));
+
+		true
+	})?;
+
+	Ok(output)
+}
+
 const fn is_newline(c: char) -> bool {
 	c == '\n' || c == '\r'
 }
diff --git a/asyncgit/src/sync/mod.rs b/asyncgit/src/sync/mod.rs
index 909bea6f..ff3a2c08 100644
--- a/asyncgit/src/sync/mod.rs
+++ b/asyncgit/src/sync/mod.rs
@@ -62,7 +62,7 @@ pub use config::{
 	get_config_string, untracked_files_config,
 	ShowUntrackedFilesConfig,
 };
-pub use diff::get_diff_commit;
+pub use diff::{get_diff_commit, unified_stage_diff};
 pub use git2::BranchType;
 pub use hooks::{
 	hooks_commit_msg, hooks_post_commit, hooks_pre_commit, HookResult,
diff --git a/src/components/commit.rs b/src/components/commit.rs
index ba32394a..95081b30 100644
--- a/src/components/commit.rs
+++ b/src/components/commit.rs
@@ -59,6 +59,7 @@ pub struct CommitComponent {
 	commit_msg_history_idx: usize,
 	options: SharedOptions,
 	verify: bool,
+	open_ai_token: Option<String>,
 }
 
 const FIRST_LINE_LIMIT: usize = 50;
@@ -90,6 +91,7 @@ impl CommitComponent {
 			commit_msg_history_idx: 0,
 			options,
 			verify: true,
+			open_ai_token: std::env::var("OPENAI_API_KEY").ok(),
 		}
 	}
 
@@ -352,6 +354,30 @@ impl CommitComponent {
 			self.input.set_text(signed_msg);
 		}
 	}
+
+	fn commit_summarize(&mut self) -> Result<()> {
+		use std::result::Result::Ok;
+
+		if let Some(api_key) = self.open_ai_token.as_ref() {
+			let mut unified_diff =
+				sync::unified_stage_diff(&self.repo.borrow())?;
+
+			while unified_diff.len() > 3500 {
+				unified_diff.pop();
+			}
+
+			match git2_summarize::git_diff_summarize(
+				&api_key,
+				&unified_diff,
+				FIRST_LINE_LIMIT,
+			) {
+				Ok(msg) => self.input.set_text(msg),
+				Err(e) => bail!(e),
+			};
+		}
+
+		Ok(())
+	}
 	fn toggle_verify(&mut self) {
 		self.verify = !self.verify;
 	}
@@ -539,6 +565,14 @@ impl Component for CommitComponent {
 				self.options.borrow().has_commit_msg_history(),
 				true,
 			));
+
+			out.push(CommandInfo::new(
+				strings::commands::commit_msg_summarize(
+					&self.key_config,
+				),
+				self.open_ai_token.is_some(),
+				true,
+			));
 		}
 
 		visibility_blocking(self)
@@ -596,6 +630,15 @@ impl Component for CommitComponent {
 					self.key_config.keys.toggle_signoff,
 				) {
 					self.signoff_commit();
+				} else if key_match(
+					e,
+					self.key_config.keys.commit_msg_summarize,
+				) {
+					try_or_popup!(
+						self,
+						"commit summary error:",
+						self.commit_summarize()
+					);
 				}
 				// stop key event propagation
 				return Ok(EventState::Consumed);
diff --git a/src/keys/key_list.rs b/src/keys/key_list.rs
index 55307193..916e1334 100644
--- a/src/keys/key_list.rs
+++ b/src/keys/key_list.rs
@@ -120,6 +120,7 @@ pub struct KeysList {
 	pub view_submodule_parent: GituiKeyEvent,
 	pub update_submodule: GituiKeyEvent,
 	pub commit_history_next: GituiKeyEvent,
+	pub commit_msg_summarize: GituiKeyEvent,
 }
 
 #[rustfmt::skip]
@@ -209,6 +210,7 @@ impl Default for KeysList {
 			view_submodule_parent: GituiKeyEvent::new(KeyCode::Char('p'),  KeyModifiers::empty()),
 			update_submodule: GituiKeyEvent::new(KeyCode::Char('u'),  KeyModifiers::empty()),
 			commit_history_next: GituiKeyEvent::new(KeyCode::Char('n'),  KeyModifiers::CONTROL),
+			commit_msg_summarize: GituiKeyEvent::new(KeyCode::Char('g'),  KeyModifiers::CONTROL),
 		}
 	}
 }
diff --git a/src/strings.rs b/src/strings.rs
index 6c3b061a..448ccff3 100644
--- a/src/strings.rs
+++ b/src/strings.rs
@@ -965,6 +965,19 @@ pub mod commands {
 			CMD_GROUP_COMMIT_POPUP,
 		)
 	}
+	pub fn commit_msg_summarize(
+		key_config: &SharedKeyConfig,
+	) -> CommandText {
+		CommandText::new(
+			format!(
+				"Summarize [{}]",
+				key_config
+					.get_hint(key_config.keys.commit_msg_summarize),
+			),
+			"use openai chat-gpt to generate commit message",
+			CMD_GROUP_COMMIT_POPUP,
+		)
+	}
 	pub fn commit_enter(key_config: &SharedKeyConfig) -> CommandText {
 		CommandText::new(
 			format!(