IDC FINALLY OH MY GOD (I think like ctx + resize propagation + some other stuff)

src/core/text.rs

@@ -5,6 +5,7 @@ use crate::prelude::*;
 pub struct Text {
     pub content: String,
     pub attrs: TextAttrs,
+    /// inner alignment of text region (within where its drawn)
     pub align: Align,
     buf: TextBuffer,
     cursor: Cursor,
@@ -40,17 +41,109 @@ impl Text {
             size: Vec2::ZERO,
         }
     }
+
     pub fn select(&mut self, pos: Vec2, size: Vec2) {
         let pos = pos - self.region().top_left.to_size(size);
         let Some(cursor) = self.buf.hit(pos.x, pos.y) else {
             return;
         };
         self.cursor = Cursor::Select {
-            line: cursor.line,
-            idx: cursor.index,
+            line: cursor.line as isize,
+            col: cursor.index as isize,
         };
     }
 
+    pub fn deselect(&mut self) {
+        self.cursor = Cursor::None;
+    }
+
+    pub fn insert(&mut self, text: &str) {
+        let i = self.update_cursor();
+        self.content.insert_str(i, text);
+
+        match &mut self.cursor {
+            Cursor::None => (),
+            Cursor::Select { line, col } => {
+                *col += 1;
+            }
+        }
+    }
+
+    pub fn backspace(&mut self) {
+        if let Some(i) = self.update_cursor().checked_sub(1) {
+            self.content.remove(i);
+            match &mut self.cursor {
+                Cursor::None => (),
+                Cursor::Select { line, col } => {
+                    *col -= 1;
+                }
+            }
+        }
+    }
+
+    pub fn delete(&mut self) {
+        let i = self.update_cursor();
+        if i != self.content.len() {
+            self.content.remove(i);
+        }
+    }
+
+    pub fn move_cursor(&mut self, dir: Dir) {
+        if let Cursor::Select { line, col } = &mut self.cursor {
+            match dir {
+                Dir::LEFT => *col -= 1,
+                Dir::RIGHT => *col += 1,
+                Dir::UP => *line -= 1,
+                Dir::DOWN => *line += 1,
+            }
+        }
+    }
+
+    pub fn update_cursor(&mut self) -> usize {
+        match &mut self.cursor {
+            Cursor::None => 0,
+            Cursor::Select { line, col } => {
+                if *col < 0 {
+                    *line -= 1;
+                }
+                if *line < 0 {
+                    *line = 0;
+                    *col = 0;
+                }
+                let mut idx = self.content.len();
+                let mut l = 0;
+                let mut c = 0;
+                let mut cur_len = 0;
+                for (i, ch) in self.content.chars().enumerate() {
+                    if ch == '\n' {
+                        l += 1;
+                        c = 0;
+                    } else {
+                        if l == *line {
+                            cur_len = i as isize + 1;
+                            if c == *col {
+                                idx = i;
+                            }
+                        }
+                        c += 1;
+                    }
+                }
+                if *col < 0 {
+                    *col = cur_len;
+                }
+                if *col > cur_len {
+                    *col = 0;
+                    *line += 1;
+                }
+                if *line > l {
+                    *line = l;
+                    *col = cur_len;
+                }
+                idx
+            }
+        }
+    }
+
     pub fn region(&self) -> UiRegion {
         UiRegion::from_size_align(self.size, self.align)
     }
@@ -58,6 +151,7 @@ impl Text {
 
 impl Widget for Text {
     fn draw(&mut self, painter: &mut Painter) {
+        self.update_cursor();
         let (handle, offset) =
             painter.render_text(&mut self.buf, &self.content, &self.attrs, &self.cursor);
         let dims = handle.size();