Add deserialisation code for size hints

1 files changed, 94 insertions, 0 deletions

diff --git a/src/clients/hints.rs b/src/clients/hints.rs
index 182c655..fdfbead 100644
--- a/src/clients/hints.rs
+++ b/src/clients/hints.rs
@@ -103,6 +103,100 @@ impl Ewm {
     }
 }
 
+#[derive(Debug)]
+pub struct Size {
+    /// The minimum size this window needs to be useful (width, height).
+    min_size: Option<(u32, u32)>,
+
+    /// The maximum size at which this window can be useful (width, height).
+    max_size: Option<(u32, u32)>,
+
+    /// The increments in which to resize this window (width, height)
+    resize_increments: Option<(u32, u32)>,
+
+    /// The ideal base size of this window (width, height)
+    base_size: Option<(u32, u32)>,
+
+    /// What side of the screen to gravitate this window towards.
+    win_gravity: Gravity,
+}
+
+impl Size {
+    const PROGRAM_MIN_SIZE: u32 = (1 << 4);
+    const PROGRAM_MAX_SIZE: u32 = (1 << 5);
+    const PROGRAM_RESIZE_INC: u32 = (1 << 6);
+    const PROGRAM_BASE_SIZE: u32 = (1 << 8);
+    const PROGRAM_WIN_GRAVITY: u32 = (1 << 9);
+
+    /// Get the size hints for the given window, if they exist and are valid.
+    pub fn get(conn: &Connection<'_>, window: Window) -> Option<Self> {
+        // https://github.com/mirror/libX11/blob/ff8706a5eae25b8bafce300527079f68a201d27f/src/GetHints.c#L59
+        // https://github.com/mirror/libX11/blob/master/src/Xatomtype.h#L77
+        let hints = conn
+            .wait_for_reply(conn.send_request(&GetProperty {
+                window,
+                delete: false,
+                property: x::ATOM_WM_NORMAL_HINTS,
+                r#type: x::ATOM_WM_SIZE_HINTS,
+                long_offset: 0,
+                long_length: 18,
+            }))
+            .ok()?;
+
+        if hints.r#type() != x::ATOM_WM_SIZE_HINTS || hints.length() < 18 || hints.format() != 32 {
+            return None;
+        }
+
+        let &[flags, _, _, _, _, min_width, min_height, max_width, max_height, width_inc, height_inc, _, _, _, _, base_width, base_height, win_gravity] =
+            hints.value::<u32>()
+        else {
+            unreachable!()
+        };
+
+        Some(Self {
+            min_size: if (flags & Self::PROGRAM_MIN_SIZE) > 0 {
+                Some((min_width, min_height))
+            } else if (flags & Self::PROGRAM_BASE_SIZE) > 0 {
+                Some((base_width, base_height))
+            } else {
+                None
+            },
+            max_size: if (flags & Self::PROGRAM_MAX_SIZE) > 0 {
+                Some((max_width, max_height))
+            } else {
+                None
+            },
+            resize_increments: if (flags & Self::PROGRAM_RESIZE_INC) > 0 {
+                Some((width_inc, height_inc))
+            } else {
+                None
+            },
+            base_size: if (flags & Self::PROGRAM_BASE_SIZE) > 0 {
+                Some((base_width, base_height))
+            } else if (flags & Self::PROGRAM_MIN_SIZE) > 0 {
+                Some((min_width, min_height))
+            } else {
+                None
+            },
+            win_gravity: if (flags & Self::PROGRAM_WIN_GRAVITY) > 0 {
+                match win_gravity {
+                    2 => Gravity::North,
+                    3 => Gravity::NorthEast,
+                    4 => Gravity::West,
+                    5 => Gravity::Center,
+                    6 => Gravity::East,
+                    7 => Gravity::SouthWest,
+                    8 => Gravity::South,
+                    9 => Gravity::SouthEast,
+                    _ => Gravity::NorthWest,
+                }
+            } else {
+                Gravity::NorthWest
+            },
+        })
+    }
+}
+
 /// Gets the `WM_TRANSIENT_FOR` hint set on a window
 pub fn transient_for(conn: &Connection, window: Window) -> Option<Window> {
     let hints = conn