feat: patch cover colors

This uses similar design for patch rendering. The cover of a patch is
everything before the `---` line that separates the email part of a
patch and the actual diff.

Currently, only `bat` was configured as an option besides the `default`

This also includes a config option for the cover renderer

Closes: #71

Signed-off-by: OJarrisonn <j.h.m.t.v.10@gmail.com>
Reviewed-by: David Tadokoro <davidbtadokoro@usp.br>
Signed-off-by: David Tadokoro <davidbtadokoro@usp.br>

src/app.rs

@@ -2,6 +2,7 @@ use crate::{log_on_error, ui::popup::PopUp};
 use ansi_to_tui::IntoText;
 use color_eyre::eyre::bail;
 use config::Config;
+use cover_renderer::render_cover;
 use logging::Logger;
 use patch_hub::lore::{lore_api_client::BlockingLoreAPIClient, lore_session, patch::Patch};
 use patch_renderer::{render_patch_preview, PatchRenderer};
@@ -19,6 +20,7 @@ use std::collections::HashMap;
 use crate::utils;
 
 mod config;
+pub mod cover_renderer;
 pub mod logging;
 pub mod patch_renderer;
 pub mod screens;
@@ -164,18 +166,31 @@ impl App {
                 let mut patches_preview: Vec<Text> = Vec::new();
                 for raw_patch in &raw_patches {
                     let raw_patch = raw_patch.replace('\t', "        ");
-                    let patch_preview =
-                        match render_patch_preview(&raw_patch, self.config.patch_renderer()) {
+
+                    let (raw_cover, raw_patch) = lore_session::split_cover(&raw_patch);
+
+                    let rendered_cover = match render_cover(raw_cover, self.config.cover_renderer())
+                    {
+                        Ok(render) => render,
+                        Err(_) => {
+                            Logger::error("Failed to render cover preview with external program");
+                            raw_cover.to_string()
+                        }
+                    };
+
+                    let rendered_patch =
+                        match render_patch_preview(raw_patch, self.config.patch_renderer()) {
                             Ok(render) => render,
                             Err(_) => {
                                 Logger::error(
                                     "Failed to render patch preview with external program",
                                 );
-                                raw_patch
+                                raw_patch.to_string()
                             }
-                        }
-                        .into_text()?;
-                    patches_preview.push(patch_preview);
+                        };
+
+                    patches_preview
+                        .push(format!("{}---\n{}", rendered_cover, rendered_patch).into_text()?);
                 }
                 self.details_actions = Some(DetailsActions {
                     representative_patch,
@@ -283,6 +298,9 @@ impl App {
             if let Ok(patch_renderer) = edit_config.extract_patch_renderer() {
                 self.config.set_patch_renderer(patch_renderer.into())
             }
+            if let Ok(cover_renderer) = edit_config.extract_cover_renderer() {
+                self.config.set_cover_renderer(cover_renderer.into())
+            }
             if let Ok(max_log_age) = edit_config.max_log_age() {
                 self.config.set_max_log_age(max_log_age)
             }

src/app/config.rs

@@ -7,7 +7,7 @@ use std::{
     path::Path,
 };
 
-use super::patch_renderer::PatchRenderer;
+use super::{cover_renderer::CoverRenderer, patch_renderer::PatchRenderer};
 
 #[cfg(test)]
 mod tests;
@@ -29,6 +29,8 @@ pub struct Config {
     data_dir: String,
     /// Renderer to use for patch previews
     patch_renderer: PatchRenderer,
+    /// Renderer to use for patchset covers
+    cover_renderer: CoverRenderer,
     /// Maximum age of a log file in days
     max_log_age: usize,
 }
@@ -47,6 +49,7 @@ impl Config {
             logs_path: format!("{data_dir}/logs"),
             git_send_email_options: "--dry-run --suppress-cc=all".to_string(),
             patch_renderer: Default::default(),
+            cover_renderer: Default::default(),
             cache_dir,
             data_dir,
             max_log_age: 30,
@@ -144,6 +147,10 @@ impl Config {
         self.patch_renderer = patch_renderer;
     }
 
+    pub fn set_cover_renderer(&mut self, cover_renderer: CoverRenderer) {
+        self.cover_renderer = cover_renderer;
+    }
+
     pub fn set_max_log_age(&mut self, max_log_age: usize) {
         self.max_log_age = max_log_age;
     }

src/app/cover_renderer.rs

@@ -0,0 +1,78 @@
+use std::{
+    fmt::Display,
+    io::Write,
+    process::{Command, Stdio},
+};
+
+use serde::{Deserialize, Serialize};
+
+use super::logging::Logger;
+
+#[derive(Debug, Serialize, Deserialize, Clone, Copy, Default)]
+pub enum CoverRenderer {
+    #[default]
+    #[serde(rename = "default")]
+    Default,
+    #[serde(rename = "bat")]
+    Bat,
+}
+
+impl From<String> for CoverRenderer {
+    fn from(value: String) -> Self {
+        match value.as_str() {
+            "bat" => CoverRenderer::Bat,
+            _ => CoverRenderer::Default,
+        }
+    }
+}
+
+impl From<&str> for CoverRenderer {
+    fn from(value: &str) -> Self {
+        match value {
+            "bat" => CoverRenderer::Bat,
+            _ => CoverRenderer::Default,
+        }
+    }
+}
+
+impl Display for CoverRenderer {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        match self {
+            CoverRenderer::Default => write!(f, "default"),
+            CoverRenderer::Bat => write!(f, "bat"),
+        }
+    }
+}
+
+pub fn render_cover(raw: &str, renderer: &CoverRenderer) -> color_eyre::Result<String> {
+    let text = match renderer {
+        CoverRenderer::Default => Ok(raw.to_string()),
+        CoverRenderer::Bat => bat_cover_renderer(raw),
+    }?;
+
+    Ok(text)
+}
+
+/// Renders a .mbx cover using the `bat` command line tool.
+///
+/// # Errors
+///
+/// If bat isn't installed or if the command fails, an error will be returned.
+fn bat_cover_renderer(patch: &str) -> color_eyre::Result<String> {
+    let mut bat = Command::new("bat")
+        .arg("-pp")
+        .arg("-f")
+        .arg("-l")
+        .arg("mbx")
+        .stdin(Stdio::piped())
+        .stdout(Stdio::piped())
+        .spawn()
+        .map_err(|e| {
+            Logger::error(format!("Failed to spawn bat for cover preview: {}", e));
+            e
+        })?;
+
+    bat.stdin.as_mut().unwrap().write_all(patch.as_bytes())?;
+    let output = bat.wait_with_output()?;
+    Ok(String::from_utf8(output.stdout)?)
+}

src/app/screens/edit_config.rs

@@ -27,6 +27,10 @@ impl EditConfig {
             EditableConfig::PatchRenderer,
             config.patch_renderer().to_string(),
         );
+        config_buffer.insert(
+            EditableConfig::CoverRenderer,
+            config.cover_renderer().to_string(),
+        );
         config_buffer.insert(EditableConfig::MaxLogAge, config.max_log_age().to_string());
 
         EditConfig {
@@ -172,6 +176,11 @@ impl EditConfig {
         Ok(patch_renderer)
     }
 
+    pub fn extract_cover_renderer(&mut self) -> Result<String, ()> {
+        let cover_renderer = self.extract_config_buffer_val(&EditableConfig::CoverRenderer);
+        Ok(cover_renderer)
+    }
+
     /// Extracts the max log age from the config
     ///
     /// # Errors
@@ -195,6 +204,7 @@ enum EditableConfig {
     DataDir,
     GitSendEmailOpt,
     PatchRenderer,
+    CoverRenderer,
     MaxLogAge,
 }
 
@@ -208,7 +218,8 @@ impl TryFrom<usize> for EditableConfig {
             2 => Ok(EditableConfig::DataDir),
             3 => Ok(EditableConfig::GitSendEmailOpt),
             4 => Ok(EditableConfig::PatchRenderer),
-            5 => Ok(EditableConfig::MaxLogAge),
+            5 => Ok(EditableConfig::CoverRenderer),
+            6 => Ok(EditableConfig::MaxLogAge),
             _ => bail!("Invalid index {} for EditableConfig", value), // Handle out of bounds
         }
     }
@@ -223,6 +234,9 @@ impl Display for EditableConfig {
             EditableConfig::PatchRenderer => {
                 write!(f, "Patch Renderer (bat, delta, diff-so-fancy)")
             }
+            EditableConfig::CoverRenderer => {
+                write!(f, "Cover Renderer (bat)")
+            }
             EditableConfig::GitSendEmailOpt => write!(f, "`git send email` option"),
             EditableConfig::MaxLogAge => write!(f, "Max Log Age (0 = forever)"),
         }

src/lore/lore_session.rs

@@ -216,6 +216,21 @@ pub fn split_patchset(patchset_path_str: &str) -> Result<Vec<String>, String> {
     Ok(patches)
 }
 
+/// Takes the string that represents a patch and splits it into the cover and the actual diff.
+///
+/// The cover is everything before the first "---" line.
+pub fn split_cover(patch: &str) -> (&str, &str) {
+    let mut cover: &str = patch;
+    let mut diff: &str = "";
+
+    if let Some(cover_end) = patch.find("\n---\n") {
+        cover = &patch[..cover_end + 1];
+        diff = &patch[cover_end + 5..];
+    }
+
+    (cover, diff)
+}
+
 fn extract_patches(mbox_path: &Path, patches: &mut Vec<String>) {
     let mut current_patch: String = String::new();
     let mut is_reading_patch: bool = false;

src/test_samples/app/config/config.json

@@ -9,5 +9,6 @@
   "cache_dir": "/cache_dir",
   "data_dir": "/data_dir",
   "patch_renderer": "default",
+  "cover_renderer": "default",
   "max_log_age": 42
 }