From 2a9edba83a90889a5003203a7b63d9a239719a16 Mon Sep 17 00:00:00 2001
From: Jordan Doyle <jordan@doyle.la>
Date: Wed, 06 Jul 2022 22:43:53 +0100
Subject: [PATCH] Implement diff on commit view with syntax highlighting

---
 Cargo.lock                 | 402 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 Cargo.toml                 |   2 ++
 src/git.rs                 | 112 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 src/main.rs                |  17 ++++++++++++++++-
 statics/style.css          |  19 +++++++++++++++++++
 src/methods/repo.rs        |   6 ++++--
 templates/repo/commit.html |   8 ++++++++
 7 files changed, 557 insertions(+), 9 deletions(-)

diff --git a/Cargo.lock b/Cargo.lock
index 1303f79..c750fb4 100644
--- a/Cargo.lock
+++ a/Cargo.lock
@@ -1,8 +1,32 @@
 # This file is automatically @generated by Cargo.
 # It is not intended for manual editing.
 version = 3
 
 [[package]]
+name = "adler"
+version = "1.0.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f26201604c87b1e01bd3d98f8d5d9a8fcbb815e8cedb41ffccbeb4bf593a35fe"
+
+[[package]]
+name = "aho-corasick"
+version = "0.7.18"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1e37cfd5e7657ada45f742d6e99ca5788580b5c529dc78faf11ece6dc702656f"
+dependencies = [
+ "memchr",
+]
+
+[[package]]
+name = "ansi_colours"
+version = "1.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "32678233b67f9056b0c144b39d46dc3218637e8d84ad6038ded339e08b19620d"
+dependencies = [
+ "rgb",
+]
+
+[[package]]
 name = "ansi_term"
 version = "0.12.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -173,13 +197,65 @@
  "http",
  "http-body",
  "mime",
+]
+
+[[package]]
+name = "base64"
+version = "0.13.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "904dfeac50f3cdaba28fc6f57fdcddb75f49ed61346676a78c4ffe55877802fd"
+
+[[package]]
+name = "bat"
+version = "0.21.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "fd1212d80800b3d7614b3725e0b2ee3b45b2b7484805d54b5660c8fa6f706305"
+dependencies = [
+ "ansi_colours",
+ "ansi_term",
+ "bincode",
+ "bytesize",
+ "clircle",
+ "console",
+ "content_inspector",
+ "encoding",
+ "flate2",
+ "globset",
+ "once_cell",
+ "path_abs",
+ "regex",
+ "semver",
+ "serde",
+ "serde_yaml",
+ "syntect",
+ "thiserror",
+ "unicode-width",
+ "walkdir",
 ]
 
 [[package]]
+name = "bincode"
+version = "1.3.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b1f45e9417d87227c7a56d22e471c6206462cba514c7590c09aff4cf6d1ddcad"
+dependencies = [
+ "serde",
+]
+
+[[package]]
 name = "bitflags"
 version = "1.3.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "bef38d45163c2f1dde094a7dfd33ccf595c92905c8f8f4fdc18d06fb1037718a"
+
+[[package]]
+name = "bstr"
+version = "0.2.17"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ba3569f383e8f1598449f1a423e72e99569137b47740b1da11ef19af3d5c3223"
+dependencies = [
+ "memchr",
+]
 
 [[package]]
 name = "bumpalo"
@@ -192,6 +268,12 @@
 version = "0.6.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "2c676a478f63e9fa2dd5368a42f28bba0d6c560b775f38583c8bbaa7fcd67c9c"
+
+[[package]]
+name = "bytemuck"
+version = "1.10.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c53dfa917ec274df8ed3c572698f381a24eef2efba9492d797301b72b6db408a"
 
 [[package]]
 name = "bytes"
@@ -200,6 +282,12 @@
 checksum = "c4872d67bab6358e59559027aa3b9157c53d9358c51423c17554809a8858e0f8"
 
 [[package]]
+name = "bytesize"
+version = "1.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6c58ec36aac5066d5ca17df51b3e70279f5670a72102f5752cb7e7c856adfc70"
+
+[[package]]
 name = "cache-padded"
 version = "1.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -293,6 +381,18 @@
 checksum = "2850f2f5a82cbf437dd5af4d49848fbdfc27c157c3d010345776f952765261c5"
 dependencies = [
  "os_str_bytes",
+]
+
+[[package]]
+name = "clircle"
+version = "0.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e68bbd985a63de680ab4d1ad77b6306611a8f961b282c8b5ab513e6de934e396"
+dependencies = [
+ "cfg-if 1.0.0",
+ "libc",
+ "serde",
+ "winapi",
 ]
 
 [[package]]
@@ -311,9 +411,42 @@
 checksum = "30ed07550be01594c6026cff2a1d7fe9c8f683caa798e12b68694ac9e88286a3"
 dependencies = [
  "cache-padded",
+]
+
+[[package]]
+name = "console"
+version = "0.15.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a28b32d32ca44b70c3e4acd7db1babf555fa026e385fb95f18028f88848b3c31"
+dependencies = [
+ "encode_unicode",
+ "libc",
+ "once_cell",
+ "regex",
+ "terminal_size",
+ "unicode-width",
+ "winapi",
+]
+
+[[package]]
+name = "content_inspector"
+version = "0.2.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b7bda66e858c683005a53a9a60c69a4aca7eeaa45d124526e389f7aec8e62f38"
+dependencies = [
+ "memchr",
 ]
 
 [[package]]
+name = "crc32fast"
+version = "1.3.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b540bd8bc810d3885c6ea91e2018302f68baba2129ab3e88f32389ee9370880d"
+dependencies = [
+ "cfg-if 1.0.0",
+]
+
+[[package]]
 name = "crossbeam-channel"
 version = "0.5.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -357,9 +490,79 @@
 dependencies = [
  "cfg-if 1.0.0",
  "once_cell",
+]
+
+[[package]]
+name = "encode_unicode"
+version = "0.3.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a357d28ed41a50f9c765dbfe56cbc04a64e53e5fc58ba79fbc34c10ef3df831f"
+
+[[package]]
+name = "encoding"
+version = "0.2.33"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6b0d943856b990d12d3b55b359144ff341533e516d94098b1d3fc1ac666d36ec"
+dependencies = [
+ "encoding-index-japanese",
+ "encoding-index-korean",
+ "encoding-index-simpchinese",
+ "encoding-index-singlebyte",
+ "encoding-index-tradchinese",
 ]
 
 [[package]]
+name = "encoding-index-japanese"
+version = "1.20141219.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "04e8b2ff42e9a05335dbf8b5c6f7567e5591d0d916ccef4e0b1710d32a0d0c91"
+dependencies = [
+ "encoding_index_tests",
+]
+
+[[package]]
+name = "encoding-index-korean"
+version = "1.20141219.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "4dc33fb8e6bcba213fe2f14275f0963fd16f0a02c878e3095ecfdf5bee529d81"
+dependencies = [
+ "encoding_index_tests",
+]
+
+[[package]]
+name = "encoding-index-simpchinese"
+version = "1.20141219.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d87a7194909b9118fc707194baa434a4e3b0fb6a5a757c73c3adb07aa25031f7"
+dependencies = [
+ "encoding_index_tests",
+]
+
+[[package]]
+name = "encoding-index-singlebyte"
+version = "1.20141219.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3351d5acffb224af9ca265f435b859c7c01537c0849754d3db3fdf2bfe2ae84a"
+dependencies = [
+ "encoding_index_tests",
+]
+
+[[package]]
+name = "encoding-index-tradchinese"
+version = "1.20141219.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "fd0e20d5688ce3cab59eb3ef3a2083a5c77bf496cb798dc6fcdb75f323890c18"
+dependencies = [
+ "encoding_index_tests",
+]
+
+[[package]]
+name = "encoding_index_tests"
+version = "0.1.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a246d82be1c9d791c5dfde9a2bd045fc3cbba3fa2b11ad558f27d01712f00569"
+
+[[package]]
 name = "error-chain"
 version = "0.12.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -381,6 +584,16 @@
 checksum = "c3fcf0cee53519c866c09b5de1f6c56ff9d647101f81c1964fa632e148896cdf"
 dependencies = [
  "instant",
+]
+
+[[package]]
+name = "flate2"
+version = "1.0.24"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f82b0f4c27ad9f8bfd1f3208d882da2b09c301bc1c828fd3a00d0216d2fbbff6"
+dependencies = [
+ "crc32fast",
+ "miniz_oxide",
 ]
 
 [[package]]
@@ -540,6 +753,19 @@
 version = "0.3.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "9b919933a397b79c37e33b77bb2aa3dc8eb6e165ad809e58ff75bc7db2e34574"
+
+[[package]]
+name = "globset"
+version = "0.4.9"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0a1e17342619edbc21a964c2afbeb6c820c6a2560032872f397bb97ea127bd0a"
+dependencies = [
+ "aho-corasick",
+ "bstr",
+ "fnv",
+ "log",
+ "regex",
+]
 
 [[package]]
 name = "hashbrown"
@@ -751,7 +977,22 @@
  "libc",
  "pkg-config",
  "vcpkg",
+]
+
+[[package]]
+name = "line-wrap"
+version = "0.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f30344350a2a51da54c1d53be93fade8a237e545dbcc4bdbe635413f2117cab9"
+dependencies = [
+ "safemem",
 ]
+
+[[package]]
+name = "linked-hash-map"
+version = "0.5.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0717cef1bc8b636c6e1c1bbdefc09e6322da8a9321966e8928ef80d20f7f770f"
 
 [[package]]
 name = "lock_api"
@@ -841,6 +1082,15 @@
 version = "0.2.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "68354c5c6bd36d73ff3feceb05efa59b6acb7626617f4962be322a825e61f79a"
+
+[[package]]
+name = "miniz_oxide"
+version = "0.5.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6f5c75688da582b8ffc1f1799e9db273f32133c49e048f614d22ec3256773ccc"
+dependencies = [
+ "adler",
+]
 
 [[package]]
 name = "mio"
@@ -932,6 +1182,28 @@
 version = "1.13.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "18a6dbe30758c9f83eb00cbea4ac95966305f5a7772f3f42ebfc7fc7eddbd8e1"
+
+[[package]]
+name = "onig"
+version = "6.3.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1eb3502504c9c8b06634b38bfdda86a9a8cef6277f3dec4d8b17c115110dd2a3"
+dependencies = [
+ "bitflags",
+ "lazy_static",
+ "libc",
+ "onig_sys",
+]
+
+[[package]]
+name = "onig_sys"
+version = "69.8.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8bf3fbc9b931b6c9af85d219c7943c274a6ad26cff7488a2210215edd5f49bf8"
+dependencies = [
+ "cc",
+ "pkg-config",
+]
 
 [[package]]
 name = "openssl-probe"
@@ -992,6 +1264,15 @@
 version = "0.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ecba01bf2678719532c5e3059e0b5f0811273d94b397088b82e3bd0a78c78fdd"
+
+[[package]]
+name = "path_abs"
+version = "0.5.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "05ef02f6342ac01d8a93b65f96db53fe68a92a15f41144f97fb00a9e669633c3"
+dependencies = [
+ "std_prelude",
+]
 
 [[package]]
 name = "percent-encoding"
@@ -1074,6 +1355,20 @@
 version = "0.3.25"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "1df8c4ec4b0627e53bdf214615ad287367e482558cf84b109250b37464dc03ae"
+
+[[package]]
+name = "plist"
+version = "1.3.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "bd39bc6cdc9355ad1dc5eeedefee696bb35c34caf21768741e81826c0bbd7225"
+dependencies = [
+ "base64",
+ "indexmap",
+ "line-wrap",
+ "serde",
+ "time 0.3.11",
+ "xml-rs",
+]
 
 [[package]]
 name = "polling"
@@ -1264,7 +1559,24 @@
 checksum = "62f25bc4c7e55e0b0b7a1d43fb893f4fa1361d0abe38b9ce4f323c2adfe6ef42"
 dependencies = [
  "bitflags",
+]
+
+[[package]]
+name = "regex"
+version = "1.6.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "4c4eb3267174b8c6c2f654116623910a0fef09c4753f8dd83db29c48a0df988b"
+dependencies = [
+ "aho-corasick",
+ "memchr",
+ "regex-syntax",
 ]
+
+[[package]]
+name = "regex-syntax"
+version = "0.6.27"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a3f87b73ce11b1619a3c6332f45341e0047173771e8b8b73f87bfeefb7b56244"
 
 [[package]]
 name = "remove_dir_all"
@@ -1273,6 +1585,15 @@
 checksum = "3acd125665422973a33ac9d3dd2df85edad0f4ae9b00dafb1a05e43a9f5ef8e7"
 dependencies = [
  "winapi",
+]
+
+[[package]]
+name = "rgb"
+version = "0.8.33"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c3b221de559e4a29df3b957eec92bc0de6bc8eaf6ca9cfed43e5e1d67ff65a34"
+dependencies = [
+ "bytemuck",
 ]
 
 [[package]]
@@ -1282,6 +1603,7 @@
  "arc-swap",
  "askama",
  "axum",
+ "bat",
  "clap",
  "futures",
  "git2",
@@ -1291,6 +1613,7 @@
  "moka",
  "path-clean",
  "serde",
+ "syntect",
  "time 0.3.11",
  "timeago",
  "tokio",
@@ -1307,6 +1630,12 @@
 version = "1.0.10"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "f3f6f92acf49d1b98f7a81226834412ada05458b7364277387724a237f062695"
+
+[[package]]
+name = "safemem"
+version = "0.3.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ef703b7cb59335eae2eb93ceb664c0eb7ea6bf567079d843e09420219668e072"
 
 [[package]]
 name = "same-file"
@@ -1380,8 +1709,20 @@
 dependencies = [
  "form_urlencoded",
  "itoa",
+ "ryu",
+ "serde",
+]
+
+[[package]]
+name = "serde_yaml"
+version = "0.8.24"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "707d15895415db6628332b737c838b88c598522e4dc70647e59b72312924aebc"
+dependencies = [
+ "indexmap",
  "ryu",
  "serde",
+ "yaml-rust",
 ]
 
 [[package]]
@@ -1444,6 +1785,12 @@
  "libc",
  "winapi",
 ]
+
+[[package]]
+name = "std_prelude"
+version = "0.2.12"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8207e78455ffdf55661170876f88daf85356e4edd54e0a3dbc79586ca1e50cbe"
 
 [[package]]
 name = "strsim"
@@ -1467,6 +1814,29 @@
 version = "0.1.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "20518fe4a4c9acf048008599e464deb21beeae3d3578418951a189c235a7a9a8"
+
+[[package]]
+name = "syntect"
+version = "5.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c6c454c27d9d7d9a84c7803aaa3c50cd088d2906fe3c6e42da3209aa623576a8"
+dependencies = [
+ "bincode",
+ "bitflags",
+ "flate2",
+ "fnv",
+ "lazy_static",
+ "once_cell",
+ "onig",
+ "plist",
+ "regex-syntax",
+ "serde",
+ "serde_derive",
+ "serde_json",
+ "thiserror",
+ "walkdir",
+ "yaml-rust",
+]
 
 [[package]]
 name = "tagptr"
@@ -1495,6 +1865,16 @@
 checksum = "bab24d30b911b2376f3a13cc2cd443142f0c81dda04c118693e35b3835757755"
 dependencies = [
  "winapi-util",
+]
+
+[[package]]
+name = "terminal_size"
+version = "0.1.17"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "633c1a546cee861a1a6d0dc69ebeca693bf4296661ba7852b9d21d159e0506df"
+dependencies = [
+ "libc",
+ "winapi",
 ]
 
 [[package]]
@@ -1548,6 +1928,7 @@
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "72c91f41dcb2f096c05f0873d667dceec1087ce5bcf984ec8ffb19acddbb3217"
 dependencies = [
+ "itoa",
  "libc",
  "num_threads",
 ]
@@ -1764,6 +2145,12 @@
 dependencies = [
  "tinyvec",
 ]
+
+[[package]]
+name = "unicode-width"
+version = "0.1.9"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3ed742d4ea2bd1176e236172c8429aaf54486e7ac098db29ffe6529e0ce50973"
 
 [[package]]
 name = "url"
@@ -1989,3 +2376,18 @@
 version = "0.36.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "c811ca4a8c853ef420abd8592ba53ddbbac90410fab6903b3e79972a631f7680"
+
+[[package]]
+name = "xml-rs"
+version = "0.8.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d2d7d3948613f75c98fd9328cfdcc45acc4d360655289d0a7d4ec931392200a3"
+
+[[package]]
+name = "yaml-rust"
+version = "0.4.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "56c1936c4cc7a1c9ab21a1ebb602eb942ba868cbd44a99cb7cdc5892335e1c85"
+dependencies = [
+ "linked-hash-map",
+]
diff --git a/Cargo.toml b/Cargo.toml
index acd49b9..2577af8 100644
--- a/Cargo.toml
+++ a/Cargo.toml
@@ -9,6 +9,7 @@
 askama = "0.11"
 arc-swap = "1.5"
 axum = "0.5"
+bat = { version = "0.21", default-features = false, features = ["build-assets"] }
 clap = { version = "3.2", features = ["cargo"] }
 futures = "0.3"
 git2 = "0.14"
@@ -18,6 +19,7 @@
 moka = { version = "0.9", features = ["future"] }
 path-clean = "0.1"
 serde = { version = "1.0", features = ["derive"] }
+syntect = "5"
 time = "0.3"
 timeago = "0.3"
 tokio = { version = "1.19", features = ["full"] }
diff --git a/src/git.rs b/src/git.rs
index 74fcf82..27a6315 100644
--- a/src/git.rs
+++ a/src/git.rs
@@ -7,8 +7,12 @@
 };
 
 use arc_swap::ArcSwapOption;
-use git2::{ObjectType, Oid, Repository, Signature};
+use git2::{
+    DiffFormat, DiffLineType, DiffOptions, DiffStatsFormat, ObjectType, Oid, Repository, Signature,
+};
 use moka::future::Cache;
+use syntect::html::{ClassStyle, ClassedHTMLGenerator};
+use syntect::parsing::SyntaxSet;
 use time::OffsetDateTime;
 
 pub type RepositoryMetadataList = BTreeMap<Option<String>, Vec<RepositoryMetadata>>;
@@ -42,7 +46,12 @@
 }
 
 impl Git {
-    pub async fn get_commit<'a>(&'a self, repo: PathBuf, commit: &str) -> Arc<Commit> {
+    pub async fn get_commit<'a>(
+        &'a self,
+        repo: PathBuf,
+        commit: &str,
+        syntax_set: Arc<SyntaxSet>,
+    ) -> Arc<Commit> {
         let commit = Oid::from_str(commit).unwrap();
 
         self.commits
@@ -50,8 +59,14 @@
                 tokio::task::spawn_blocking(move || {
                     let repo = Repository::open_bare(repo).unwrap();
                     let commit = repo.find_commit(commit).unwrap();
+                    let (diff_output, diff_stats) =
+                        fetch_diff_and_stats(&repo, &commit, &syntax_set);
+
+                    let mut commit = Commit::from(commit);
+                    commit.diff_stats = diff_stats;
+                    commit.diff = diff_output;
 
-                    Arc::new(Commit::from(commit))
+                    Arc::new(commit)
                 })
                 .await
                 .unwrap()
@@ -153,13 +168,17 @@
             .await
     }
 
-    pub async fn get_latest_commit(&self, repo: PathBuf) -> Commit {
+    pub async fn get_latest_commit(&self, repo: PathBuf, syntax_set: Arc<SyntaxSet>) -> Commit {
         tokio::task::spawn_blocking(move || {
             let repo = Repository::open_bare(repo).unwrap();
             let head = repo.head().unwrap();
             let commit = head.peel_to_commit().unwrap();
-
-            Commit::from(commit)
+            let (diff_output, diff_stats) = fetch_diff_and_stats(&repo, &commit, &syntax_set);
+
+            let mut commit = Commit::from(commit);
+            commit.diff_stats = diff_stats;
+            commit.diff = diff_output;
+            commit
         })
         .await
         .unwrap()
@@ -316,6 +335,8 @@
     parents: Vec<String>,
     summary: String,
     body: String,
+    pub diff_stats: String,
+    pub diff: String,
 }
 
 impl From<git2::Commit<'_>> for Commit {
@@ -328,6 +349,8 @@
             parents: commit.parent_ids().map(|v| v.to_string()).collect(),
             summary: commit.summary().unwrap().to_string(),
             body: commit.body().map(ToString::to_string).unwrap_or_default(),
+            diff_stats: String::with_capacity(0),
+            diff: String::with_capacity(0),
         }
     }
 }
@@ -360,6 +383,83 @@
     pub fn body(&self) -> &str {
         &self.body
     }
+}
+
+fn fetch_diff_and_stats(
+    repo: &git2::Repository,
+    commit: &git2::Commit<'_>,
+    syntax_set: &SyntaxSet,
+) -> (String, String) {
+    let current_tree = commit.tree().unwrap();
+    let parent_tree = commit.parents().next().and_then(|v| v.tree().ok());
+    let mut diff_opts = DiffOptions::new();
+    let diff = repo
+        .diff_tree_to_tree(
+            parent_tree.as_ref(),
+            Some(&current_tree),
+            Some(&mut diff_opts),
+        )
+        .unwrap();
+    let diff_stats = diff
+        .stats()
+        .unwrap()
+        .to_buf(DiffStatsFormat::FULL, 80)
+        .unwrap()
+        .as_str()
+        .unwrap()
+        .to_string();
+    let diff_output = format_diff(&diff, &syntax_set);
+
+    (diff_output, diff_stats)
+}
+
+fn format_diff(diff: &git2::Diff<'_>, syntax_set: &SyntaxSet) -> String {
+    let mut diff_output = String::new();
+
+    diff.print(DiffFormat::Patch, |delta, _diff_hunk, diff_line| {
+        let (class, prefix, should_highlight_as_source) = match diff_line.origin_value() {
+            DiffLineType::Addition => (Some("add-line"), "+", true),
+            DiffLineType::Deletion => (Some("remove-line"), "-", true),
+            DiffLineType::Context => (None, " ", true),
+            DiffLineType::AddEOFNL => (Some("remove-line"), "", false),
+            DiffLineType::DeleteEOFNL => (Some("add-line"), "", false),
+            DiffLineType::FileHeader => (Some("file-header"), "", false),
+            _ => (None, "", false),
+        };
+
+        let line = std::str::from_utf8(diff_line.content()).unwrap();
+
+        let extension = if should_highlight_as_source {
+            let path = delta.new_file().path().unwrap();
+            path.extension()
+                .or(path.file_name())
+                .unwrap()
+                .to_string_lossy()
+        } else {
+            Cow::Borrowed("patch")
+        };
+        let syntax = syntax_set
+            .find_syntax_by_extension(&extension)
+            .unwrap_or(syntax_set.find_syntax_plain_text());
+        let mut html_generator =
+            ClassedHTMLGenerator::new_with_class_style(syntax, &syntax_set, ClassStyle::Spaced);
+        html_generator
+            .parse_html_for_line_which_includes_newline(line)
+            .unwrap();
+        if let Some(class) = class {
+            diff_output.push_str(&format!("<span class=\"diff-{class}\">"));
+        }
+        diff_output.push_str(prefix);
+        diff_output.push_str(&html_generator.finalize());
+        if class.is_some() {
+            diff_output.push_str("</span>");
+        }
+
+        true
+    })
+    .unwrap();
+
+    diff_output
 }
 
 fn fetch_repository_metadata_impl(
diff --git a/src/main.rs b/src/main.rs
index 5fc349e..a6a4711 100644
--- a/src/main.rs
+++ a/src/main.rs
@@ -1,9 +1,12 @@
 #![deny(clippy::pedantic)]
 
 use axum::{
     body::Body, handler::Handler, http::HeaderValue, response::Response, routing::get, Extension,
     Router,
 };
+use bat::assets::HighlightingAssets;
+use std::sync::Arc;
+use syntect::html::ClassStyle;
 use tower_layer::layer_fn;
 
 use crate::{git::Git, layers::logger::LoggingMiddleware};
@@ -21,15 +24,27 @@
     let subscriber = subscriber.pretty();
     subscriber.init();
 
+    let bat_assets = HighlightingAssets::from_binary();
+    let syntax_set = bat_assets.get_syntax_set().unwrap().clone();
+    let theme = bat_assets.get_theme("GitHub");
+    let css = Box::leak(
+        syntect::html::css_for_theme_with_class_style(theme, ClassStyle::Spaced)
+            .unwrap()
+            .into_boxed_str()
+            .into_boxed_bytes(),
+    );
+
     let app = Router::new()
         .route("/", get(methods::index::handle))
         .route(
             "/style.css",
             get(static_css(include_bytes!("../statics/style.css"))),
         )
+        .route("/highlight.css", get(static_css(css)))
         .fallback(methods::repo::service.into_service())
         .layer(layer_fn(LoggingMiddleware))
-        .layer(Extension(Git::default()));
+        .layer(Extension(Git::default()))
+        .layer(Extension(Arc::new(syntax_set)));
 
     axum::Server::bind(&"127.0.0.1:3333".parse().unwrap())
         .serve(app.into_make_service_with_connect_info::<std::net::SocketAddr>())
diff --git a/statics/style.css b/statics/style.css
index 51cae2b..4cf9841 100644
--- a/statics/style.css
+++ a/statics/style.css
@@ -91,3 +91,22 @@
     font-size: 1.5em;
     font-weight: bold;
 }
+
+
+.diff-file-header {
+    font-weight: bold;
+}
+
+.diff-file-header > span > span {
+    font-weight: normal;
+}
+
+.diff-add-line {
+    background: #e6ffec;
+    display: block;
+}
+
+.diff-remove-line {
+    background: #ffebe9;
+    display: block;
+}
diff --git a/src/methods/repo.rs b/src/methods/repo.rs
index a1d583c..a04fd75 100644
--- a/src/methods/repo.rs
+++ a/src/methods/repo.rs
@@ -14,6 +14,7 @@
 };
 use path_clean::PathClean;
 use serde::Deserialize;
+use syntect::parsing::SyntaxSet;
 use tower::{util::BoxCloneService, Service};
 
 use super::filters;
@@ -205,6 +206,7 @@
     Extension(repo): Extension<Repository>,
     Extension(RepositoryPath(repository_path)): Extension<RepositoryPath>,
     Extension(git): Extension<Git>,
+    Extension(syntax_set): Extension<Arc<SyntaxSet>>,
     Query(query): Query<CommitQuery>,
 ) -> Html<String> {
     #[derive(Template)]
@@ -218,9 +220,9 @@
         View {
             repo,
             commit: if let Some(commit) = query.id {
-                git.get_commit(repository_path, &commit).await
+                git.get_commit(repository_path, &commit, syntax_set).await
             } else {
-                Arc::new(git.get_latest_commit(repository_path).await)
+                Arc::new(git.get_latest_commit(repository_path, syntax_set).await)
             },
         }
         .render()
diff --git a/templates/repo/commit.html b/templates/repo/commit.html
index 70eeee2..647a32e 100644
--- a/templates/repo/commit.html
+++ a/templates/repo/commit.html
@@ -1,5 +1,9 @@
 {% extends "repo/base.html" %}
 
+{% block head %}
+<link rel="stylesheet" type="text/css" href="/highlight.css" />
+{% endblock %}
+
 {% block commit_nav_class %}active{% endblock %}
 
 {% block content %}
@@ -34,4 +38,8 @@
 
 <h2>{{ commit.summary() }}</h2>
 <pre>{{ commit.body() }}</pre>
+
+<h3>Diff</h3>
+<pre>{{ commit.diff_stats|safe }}
+{{ commit.diff|safe }}</pre>
 {% endblock %}--
rgit 0.1.3