From eb5f867f0541bc6ea8f7a64930f488d63313afa0 Mon Sep 17 00:00:00 2001
From: Sam Denty <sam@samdenty.com>
Date: Fri, 23 Dec 2022 23:20:28 +0000
Subject: [PATCH] feat(0.4.0): add support for GIF

---
 Cargo.lock           |  2 +-
 Cargo.toml           |  2 +-
 src/icon_info.rs     | 13 +++++++++++--
 src/icon_size/gif.rs | 24 ++++++++++++++++++++++++
 src/icon_size/mod.rs |  2 ++
 5 files changed, 39 insertions(+), 4 deletions(-)
 create mode 100644 src/icon_size/gif.rs

diff --git a/Cargo.lock b/Cargo.lock
index 82a98e4..d772742 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1525,7 +1525,7 @@ checksum = "7bd3e3206899af3f8b12af284fafc038cc1dc2b41d1b89dd17297221c5d225de"
 
 [[package]]
 name = "site_icons"
-version = "0.3.10"
+version = "0.4.0"
 dependencies = [
  "byteorder",
  "clap",
diff --git a/Cargo.toml b/Cargo.toml
index 28154c2..a51a543 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "site_icons"
-version = "0.3.10"
+version = "0.4.0"
 authors = ["Sam Denty <sam@samdenty.com>"]
 edition = "2018"
 license = "GPL-3.0"
diff --git a/src/icon_info.rs b/src/icon_info.rs
index b1096ba..b08a2ec 100644
--- a/src/icon_info.rs
+++ b/src/icon_info.rs
@@ -17,6 +17,7 @@ enum IconKind {
   PNG,
   JPEG,
   ICO,
+  GIF,
 }
 
 #[derive(Clone, Debug, Serialize, Deserialize, Eq, PartialEq)]
@@ -26,6 +27,7 @@ pub enum IconInfo {
   PNG { size: IconSize },
   JPEG { size: IconSize },
   ICO { sizes: IconSizes },
+  GIF { size: IconSize },
   SVG,
 }
 
@@ -50,6 +52,10 @@ impl IconInfo {
         let size = get_jpeg_size(reader).await?;
         Ok(IconInfo::JPEG { size })
       }
+      (Some(IconKind::GIF), _) | (_, &[0x47, 0x49]) => {
+        let size = get_gif_size(reader).await?;
+        Ok(IconInfo::GIF { size })
+      }
       _ => Err(format!("unknown icon type ({:?})", header).into()),
     }
   }
@@ -140,7 +146,7 @@ impl IconInfo {
   pub fn size(&self) -> Option<&IconSize> {
     match self {
       IconInfo::ICO { sizes } => Some(sizes.largest()),
-      IconInfo::PNG { size } | IconInfo::JPEG { size } => Some(size),
+      IconInfo::PNG { size } | IconInfo::JPEG { size } | IconInfo::GIF { size } => Some(size),
       IconInfo::SVG => None,
     }
   }
@@ -148,7 +154,9 @@ impl IconInfo {
   pub fn sizes(&self) -> Option<IconSizes> {
     match self {
       IconInfo::ICO { sizes } => Some((*sizes).clone()),
-      IconInfo::PNG { size } | IconInfo::JPEG { size } => Some((*size).into()),
+      IconInfo::PNG { size } | IconInfo::JPEG { size } | IconInfo::GIF { size } => {
+        Some((*size).into())
+      }
       IconInfo::SVG => None,
     }
   }
@@ -159,6 +167,7 @@ impl Display for IconInfo {
     match self {
       IconInfo::PNG { size } => write!(f, "png {}", size),
       IconInfo::JPEG { size } => write!(f, "jpeg {}", size),
+      IconInfo::GIF { size } => write!(f, "gif {}", size),
       IconInfo::ICO { sizes } => write!(f, "ico {}", sizes),
       IconInfo::SVG => write!(f, "svg"),
     }
diff --git a/src/icon_size/gif.rs b/src/icon_size/gif.rs
new file mode 100644
index 0000000..e75a60f
--- /dev/null
+++ b/src/icon_size/gif.rs
@@ -0,0 +1,24 @@
+use super::IconSize;
+use byteorder::{LittleEndian, ReadBytesExt};
+use futures::prelude::*;
+use std::{
+  error::Error,
+  io::{Cursor, Seek, SeekFrom},
+};
+
+pub async fn get_gif_size<R: AsyncRead + Unpin>(
+  reader: &mut R,
+) -> Result<IconSize, Box<dyn Error>> {
+  let mut header = [0; 8];
+  reader.read_exact(&mut header).await?;
+  let header = &mut Cursor::new(header);
+
+  assert_slice_eq!(header, 0, b"F8", "bad header");
+
+  header.seek(SeekFrom::Start(4))?;
+
+  let width = header.read_u16::<LittleEndian>()? as u32;
+  let height = header.read_u16::<LittleEndian>()? as u32;
+
+  Ok(IconSize::new(width, height))
+}
diff --git a/src/icon_size/mod.rs b/src/icon_size/mod.rs
index 398f172..71ca2ca 100644
--- a/src/icon_size/mod.rs
+++ b/src/icon_size/mod.rs
@@ -1,8 +1,10 @@
+mod gif;
 mod ico;
 mod icon_sizes;
 mod jpeg;
 mod png;
 
+pub use gif::*;
 pub use ico::*;
 pub use icon_sizes::*;
 pub use jpeg::*;