From a74fc5ba675bba862a7ce3bf4747cc0f9443a5c0 Mon Sep 17 00:00:00 2001
From: Ashley Wulber <ashley@system76.com>
Date: Wed, 28 Feb 2024 15:17:37 -0500
Subject: [PATCH] refactor: Text mimes as their own type

---
 src/mime.rs | 36 +++++++++++++++++++++++++-----------
 src/text.rs | 20 +++++++++++++-------
 2 files changed, 38 insertions(+), 18 deletions(-)

diff --git a/src/mime.rs b/src/mime.rs
index 40be7ef..60377f2 100644
--- a/src/mime.rs
+++ b/src/mime.rs
@@ -16,40 +16,54 @@ impl fmt::Display for Error {
 
 impl error::Error for Error {}
 
-/// Mime type supported by clipboard.
-#[derive(Clone, Eq, PartialEq, Debug, Default)]
-#[repr(u8)]
-pub enum MimeType {
+#[derive(Copy, Clone, Eq, PartialEq, Debug, Default)]
+pub enum Text {
     #[default]
     /// text/plain;charset=utf-8 mime type.
     ///
     /// The primary mime type used by most clients
-    TextPlainUtf8,
+    TextPlainUtf8 = 0,
     /// UTF8_STRING mime type.
     ///
     /// Some X11 clients are using only this mime type, so we
     /// should have it as a fallback just in case.
-    Utf8String,
+    Utf8String = 1,
     /// text/plain mime type.
     ///
     /// Fallback without charset parameter.
-    TextPlain,
+    TextPlain = 2,
+}
+
+/// Mime type supported by clipboard.
+#[derive(Clone, Eq, PartialEq, Debug)]
+pub enum MimeType {
+    /// Text mime type.
+    Text(Text),
     /// Other mime type.
     Other(Cow<'static, str>),
 }
 
+impl Default for MimeType {
+    fn default() -> Self {
+        MimeType::Text(Text::default())
+    }
+}
+
 impl AsRef<str> for MimeType {
     fn as_ref(&self) -> &str {
         match self {
             MimeType::Other(s) => s.as_ref(),
-            m => ALLOWED_TEXT_MIME_TYPES[m.discriminant() as usize],
+            m => ALLOWED_TEXT_MIME_TYPES[m.discriminant()],
         }
     }
 }
 
 impl MimeType {
-    fn discriminant(&self) -> u8 {
-        unsafe { *(self as *const Self as *const u8) }
+    fn discriminant(&self) -> usize {
+        match self {
+            MimeType::Text(t) => *t as usize,
+            MimeType::Other(_) => 3,
+        }
     }
 }
 
@@ -87,7 +101,7 @@ impl std::fmt::Display for MimeType {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
         match self {
             MimeType::Other(m) => write!(f, "{}", m),
-            m => write!(f, "{}", ALLOWED_TEXT_MIME_TYPES[m.discriminant() as usize]),
+            m => write!(f, "{}", ALLOWED_TEXT_MIME_TYPES[m.discriminant()]),
         }
     }
 }
diff --git a/src/text.rs b/src/text.rs
index a092e2b..4943b92 100644
--- a/src/text.rs
+++ b/src/text.rs
@@ -1,6 +1,6 @@
 use std::borrow::Cow;
 
-use crate::mime::{normalize_to_lf, AllowedMimeTypes, AsMimeTypes, Error, MimeType};
+use crate::mime::{self, normalize_to_lf, AllowedMimeTypes, AsMimeTypes, Error, MimeType};
 
 pub struct Text(pub String);
 
@@ -16,8 +16,10 @@ impl TryFrom<(Vec<u8>, MimeType)> for Text {
 
         // Post-process the content according to mime type.
         let content = match mime_type {
-            MimeType::TextPlainUtf8 | MimeType::TextPlain => normalize_to_lf(content),
-            MimeType::Utf8String => content,
+            MimeType::Text(mime::Text::TextPlainUtf8 | mime::Text::TextPlain) => {
+                normalize_to_lf(content)
+            },
+            MimeType::Text(mime::Text::Utf8String) => content,
             MimeType::Other(_) => return Err(Error),
         };
         Ok(Text(content))
@@ -26,7 +28,11 @@ impl TryFrom<(Vec<u8>, MimeType)> for Text {
 
 impl AllowedMimeTypes for Text {
     fn allowed() -> Cow<'static, [MimeType]> {
-        Cow::Borrowed(&[MimeType::TextPlainUtf8, MimeType::Utf8String, MimeType::TextPlain])
+        Cow::Borrowed(&[
+            MimeType::Text(mime::Text::TextPlainUtf8),
+            MimeType::Text(mime::Text::Utf8String),
+            MimeType::Text(mime::Text::TextPlain),
+        ])
     }
 }
 
@@ -37,9 +43,9 @@ impl AsMimeTypes for Text {
 
     fn as_bytes(&self, mime_type: &MimeType) -> Option<Cow<'static, [u8]>> {
         match mime_type {
-            MimeType::TextPlainUtf8 | MimeType::Utf8String | MimeType::TextPlain => {
-                Some(Cow::Owned(self.0.as_bytes().to_owned()))
-            },
+            MimeType::Text(
+                mime::Text::TextPlainUtf8 | mime::Text::Utf8String | mime::Text::TextPlain,
+            ) => Some(Cow::Owned(self.0.as_bytes().to_owned())),
             MimeType::Other(_) => None,
         }
     }