🎉 Set DOM text editor element caret

render-wasm/src/state/text_editor.rs

@@ -0,0 +1,103 @@
+#![allow(dead_code)]
+
+use crate::shapes::TextPositionWithAffinity;
+
+/// TODO: Now this is just a tuple with 2 i32 working
+/// as indices (paragraph and leaf).
+#[derive(Debug, PartialEq, Clone, Copy)]
+pub struct TextNodePosition {
+    pub paragraph: i32,
+    pub leaf: i32,
+}
+
+impl TextNodePosition {
+    pub fn new(paragraph: i32, leaf: i32) -> Self {
+        Self { paragraph, leaf }
+    }
+
+    #[allow(dead_code)]
+    pub fn is_invalid(&self) -> bool {
+        self.paragraph < 0 || self.leaf < 0
+    }
+}
+
+pub struct TextPosition {
+    node: Option<TextNodePosition>,
+    offset: i32,
+}
+
+impl TextPosition {
+    pub fn new() -> Self {
+        Self {
+            node: None,
+            offset: -1,
+        }
+    }
+
+    pub fn set(&mut self, node: Option<TextNodePosition>, offset: i32) {
+        self.node = node;
+        self.offset = offset;
+    }
+}
+
+pub struct TextSelection {
+    focus: TextPosition,
+    anchor: TextPosition,
+}
+
+impl TextSelection {
+    pub fn new() -> Self {
+        Self {
+            focus: TextPosition::new(),
+            anchor: TextPosition::new(),
+        }
+    }
+
+    #[allow(dead_code)]
+    pub fn is_caret(&self) -> bool {
+        self.focus.node == self.anchor.node && self.focus.offset == self.anchor.offset
+    }
+
+    #[allow(dead_code)]
+    pub fn is_selection(&self) -> bool {
+        !self.is_caret()
+    }
+
+    pub fn set_focus(&mut self, node: Option<TextNodePosition>, offset: i32) {
+        self.focus.set(node, offset);
+    }
+
+    pub fn set_anchor(&mut self, node: Option<TextNodePosition>, offset: i32) {
+        self.anchor.set(node, offset);
+    }
+
+    pub fn set(&mut self, node: Option<TextNodePosition>, offset: i32) {
+        self.set_focus(node, offset);
+        self.set_anchor(node, offset);
+    }
+}
+
+pub struct TextEditorState {
+    selection: TextSelection,
+}
+
+impl TextEditorState {
+    pub fn new() -> Self {
+        Self {
+            selection: TextSelection::new(),
+        }
+    }
+
+    pub fn set_caret_position_from(
+        &mut self,
+        text_position_with_affinity: TextPositionWithAffinity,
+    ) {
+        self.selection.set(
+            Some(TextNodePosition::new(
+                text_position_with_affinity.paragraph,
+                text_position_with_affinity.leaf,
+            )),
+            text_position_with_affinity.offset,
+        );
+    }
+}