Move `Icon` to `iced` crate and introduce `Error`

2 files changed, 138 insertions, 4 deletions

diff --git a/src/window/icon.rs b/src/window/icon.rs
new file mode 100644
index 00000000..15e0312d
--- /dev/null
+++ b/src/window/icon.rs
@@ -0,0 +1,132 @@
+//! Attach an icon to the window of your application.
+use std::fmt;
+use std::io;
+
+/// The icon of a window.
+#[cfg(not(target_arch = "wasm32"))]
+#[derive(Debug, Clone)]
+pub struct Icon(iced_winit::winit::window::Icon);
+
+/// The icon of a window.
+#[cfg(target_arch = "wasm32")]
+#[derive(Debug, Clone)]
+pub struct Icon;
+
+impl Icon {
+    /// Creates an icon from 32bpp RGBA data.
+    #[cfg(not(target_arch = "wasm32"))]
+    pub fn from_rgba(
+        rgba: Vec<u8>,
+        width: u32,
+        height: u32,
+    ) -> Result<Self, Error> {
+        let raw =
+            iced_winit::winit::window::Icon::from_rgba(rgba, width, height)?;
+
+        Ok(Icon(raw))
+    }
+
+    /// Creates an icon from 32bpp RGBA data.
+    #[cfg(target_arch = "wasm32")]
+    pub fn from_rgba(
+        _rgba: Vec<u8>,
+        _width: u32,
+        _height: u32,
+    ) -> Result<Self, Error> {
+        Ok(Icon)
+    }
+}
+
+/// An error produced when using `Icon::from_rgba` with invalid arguments.
+#[derive(Debug)]
+pub enum Error {
+    /// The provided RGBA data isn't divisble by 4.
+    ///
+    /// Therefore, it cannot be safely interpreted as 32bpp RGBA pixels.
+    InvalidData {
+        /// The length of the provided RGBA data.
+        byte_count: usize,
+    },
+
+    /// The number of RGBA pixels does not match the provided dimensions.
+    DimensionsMismatch {
+        /// The provided width.
+        width: u32,
+        /// The provided height.
+        height: u32,
+        /// The amount of pixels of the provided RGBA data.
+        pixel_count: usize,
+    },
+
+    /// The underlying OS failed to create the icon.
+    OsError(io::Error),
+}
+
+#[cfg(not(target_arch = "wasm32"))]
+impl From<iced_winit::winit::window::BadIcon> for Error {
+    fn from(error: iced_winit::winit::window::BadIcon) -> Self {
+        use iced_winit::winit::window::BadIcon;
+
+        match error {
+            BadIcon::ByteCountNotDivisibleBy4 { byte_count } => {
+                Error::InvalidData { byte_count }
+            }
+            BadIcon::DimensionsVsPixelCount {
+                width,
+                height,
+                pixel_count,
+                ..
+            } => Error::DimensionsMismatch {
+                width,
+                height,
+                pixel_count,
+            },
+            BadIcon::OsError(os_error) => Error::OsError(os_error),
+        }
+    }
+}
+
+#[cfg(not(target_arch = "wasm32"))]
+impl From<Icon> for iced_winit::winit::window::Icon {
+    fn from(icon: Icon) -> Self {
+        icon.0
+    }
+}
+
+impl fmt::Display for Error {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        match self {
+            Error::InvalidData { byte_count } => {
+                write!(f,
+                "The provided RGBA data (with length {:?}) isn't divisble by \
+                4. Therefore, it cannot be safely interpreted as 32bpp RGBA \
+                pixels.",
+                byte_count,
+            )
+            }
+            Error::DimensionsMismatch {
+                width,
+                height,
+                pixel_count,
+            } => {
+                write!(f,
+                "The number of RGBA pixels ({:?}) does not match the provided \
+                dimensions ({:?}x{:?}).",
+                width, height, pixel_count,
+            )
+            }
+            Error::OsError(e) => write!(
+                f,
+                "The underlying OS failed to create the window \
+                icon: {:?}",
+                e
+            ),
+        }
+    }
+}
+
+impl std::error::Error for Error {
+    fn source(&self) -> Option<&(dyn std::error::Error + 'static)> {
+        Some(self)
+    }
+}
diff --git a/src/window/settings.rs b/src/window/settings.rs
index 961e8d66..2046f2d9 100644
--- a/src/window/settings.rs
+++ b/src/window/settings.rs
@@ -1,5 +1,7 @@
+use crate::window::Icon;
+
 /// The window settings of an application.
-#[derive(Debug, Clone, PartialEq, Eq)]
+#[derive(Debug, Clone)]
 pub struct Settings {
     /// The initial size of the window.
     pub size: (u32, u32),
@@ -16,8 +18,8 @@ pub struct Settings {
     /// Whether the window should have a border, a title bar, etc. or not.
     pub decorations: bool,
 
-    /// The window icon, which is also usually used in the taskbar
-    pub icon: Option<iced_winit::settings::Icon>,
+    /// The icon of the window.
+    pub icon: Option<Icon>,
 }
 
 impl Default for Settings {
@@ -42,7 +44,7 @@ impl From<Settings> for iced_winit::settings::Window {
             max_size: settings.max_size,
             resizable: settings.resizable,
             decorations: settings.decorations,
-            icon: settings.icon,
+            icon: settings.icon.map(Icon::into),
             platform_specific: Default::default(),
         }
     }