actually use the text library for text editing (fully working I think but code isn't cleanest)

src/core/mod.rs

@@ -7,6 +7,7 @@ mod sized;
 mod span;
 mod stack;
 mod text;
+mod text_edit;
 mod trait_fns;
 
 pub use align::*;
@@ -18,4 +19,5 @@ pub use sized::*;
 pub use span::*;
 pub use stack::*;
 pub use text::*;
+pub use text_edit::*;
 pub use trait_fns::*;

src/core/text.rs

@@ -1,4 +1,4 @@
-use cosmic_text::{Family, Metrics};
+use cosmic_text::{Attrs, Family, FontSystem, Metrics, Shaping};
 
 use crate::prelude::*;
 
@@ -7,8 +7,7 @@ pub struct Text {
     pub attrs: TextAttrs,
     /// inner alignment of text region (within where its drawn)
     pub align: Align,
-    buf: TextBuffer,
-    cursor: Cursor,
+    pub(super) buf: TextBuffer,
     size: Vec2,
 }
 
@@ -37,129 +36,33 @@ impl Text {
             buf: TextBuffer::new_empty(Metrics::new(attrs.font_size, attrs.line_height)),
             attrs,
             align: Align::Center,
-            cursor: Cursor::None,
             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 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 { col, .. } => {
-                *col += 1;
-            }
-        }
-        self.update_cursor();
-    }
-
-    pub fn backspace(&mut self) {
-        if let Some(i) = self
-            .update_cursor()
-            .checked_sub(1)
-            .map(|i| self.content.floor_char_boundary(i))
-        {
-            self.content.remove(i);
-            match &mut self.cursor {
-                Cursor::None => (),
-                Cursor::Select { 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) {
-        self.update_cursor();
-        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.char_indices() {
-                    if ch == '\n' {
-                        l += 1;
-                        c = 0;
-                    } else {
-                        if l == *line {
-                            cur_len = c + 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)
     }
+
+    fn update_buf(&mut self, font_system: &mut FontSystem) {
+        self.buf.set_metrics(
+            font_system,
+            Metrics::new(self.attrs.font_size, self.attrs.line_height),
+        );
+        self.buf.set_text(
+            font_system,
+            &self.content,
+            &Attrs::new().family(self.attrs.family),
+            Shaping::Advanced,
+        );
+    }
 }
 
 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 font_system = &mut painter.text_data().font_system;
+        self.update_buf(font_system);
+        let (handle, offset) = painter.render_text(&mut self.buf, &self.attrs, &VisualCursor::None);
         let dims = handle.size();
         self.size = offset.size(&handle);
         let mut region = self.region();
@@ -169,8 +72,8 @@ impl Widget for Text {
     }
 
     fn get_size(&mut self, ctx: &mut SizeCtx) -> Vec2 {
-        let (handle, offset) =
-            ctx.draw_text(&mut self.buf, &self.content, &self.attrs, &self.cursor);
+        self.update_buf(&mut ctx.text.font_system);
+        let (handle, offset) = ctx.draw_text(&mut self.buf, &self.attrs, &VisualCursor::None);
         offset.size(&handle)
     }
 }

src/core/text_edit.rs

@@ -0,0 +1,203 @@
+use crate::prelude::*;
+use cosmic_text::{Attrs, Cursor, Family, FontSystem, Metrics, Motion, Shaping};
+
+pub struct TextEdit {
+    pub attrs: TextAttrs,
+    /// inner alignment of text region (within where its drawn)
+    pub align: Align,
+    buf: TextBuffer,
+    cursor: Option<Cursor>,
+    size: Vec2,
+}
+
+impl TextEdit {
+    pub fn region(&self) -> UiRegion {
+        UiRegion::from_size_align(self.size, self.align)
+    }
+}
+
+impl Widget for TextEdit {
+    fn draw(&mut self, painter: &mut Painter) {
+        let font_system = &mut painter.text_data().font_system;
+        self.buf.shape_until_scroll(font_system, false);
+        self.attrs.apply(font_system, &mut self.buf);
+        let (handle, offset) = painter.render_text(
+            &mut self.buf,
+            &self.attrs,
+            &match self.cursor {
+                None => VisualCursor::None,
+                Some(cursor) => VisualCursor::Select {
+                    line: cursor.line as isize,
+                    col: cursor.index as isize,
+                },
+            },
+        );
+        let dims = handle.size();
+        self.size = offset.size(&handle);
+        let mut region = self.region();
+        region.top_left.offset += offset.top_left;
+        region.bot_right.offset = region.top_left.offset + dims;
+        painter.draw_texture_within(&handle, region);
+    }
+
+    fn get_size(&mut self, ctx: &mut SizeCtx) -> Vec2 {
+        let (handle, offset) = ctx.draw_text(&mut self.buf, &self.attrs, &VisualCursor::None);
+        offset.size(&handle)
+    }
+}
+
+pub struct TextEditBuilder {
+    pub content: String,
+    pub attrs: TextAttrs,
+    /// inner alignment of text region (within where its drawn)
+    pub align: Align,
+}
+
+impl TextEditBuilder {
+    pub fn font_size(mut self, size: impl UiNum) -> Self {
+        self.attrs.font_size = size.to_f32();
+        self.attrs.line_height = self.attrs.font_size * 1.1;
+        self
+    }
+    pub fn color(mut self, color: UiColor) -> Self {
+        self.attrs.color = color;
+        self
+    }
+    pub fn family(mut self, family: Family<'static>) -> Self {
+        self.attrs.family = family;
+        self
+    }
+    pub fn line_height(mut self, height: f32) -> Self {
+        self.attrs.line_height = height;
+        self
+    }
+}
+
+pub struct TextEditCtx<'a> {
+    pub text: &'a mut TextEdit,
+    pub font_system: &'a mut FontSystem,
+}
+
+impl<'a> TextEditCtx<'a> {
+    pub fn motion(&mut self, motion: Motion) {
+        if let Some(cursor) = self.text.cursor
+            && let Some((cursor, _)) =
+                self.text
+                    .buf
+                    .cursor_motion(self.font_system, cursor, None, motion)
+        {
+            self.text.cursor = Some(cursor);
+        }
+    }
+    pub fn insert(&mut self, text: &str) {
+        if let Some(cursor) = &mut self.text.cursor {
+            let line = &mut self.text.buf.lines[cursor.line];
+            let mut line_text = line.text().to_string();
+            line_text.insert_str(cursor.index, text);
+            line.set_text(line_text, line.ending(), line.attrs_list().clone());
+            for _ in 0..text.len() {
+                self.motion(Motion::Right);
+            }
+        }
+    }
+
+    pub fn newline(&mut self) {
+        if let Some(cursor) = &mut self.text.cursor {
+            let line = &mut self.text.buf.lines[cursor.line];
+            let new = line.split_off(cursor.index);
+            cursor.line += 1;
+            self.text.buf.lines.insert(cursor.line, new);
+            cursor.index = 0;
+        }
+    }
+
+    pub fn backspace(&mut self) {
+        if let Some(cursor) = &mut self.text.cursor {
+            if cursor.index == 0 {
+                if cursor.line == 0 {
+                    return;
+                }
+                let add = self.text.buf.lines.remove(cursor.line).into_text();
+                cursor.line -= 1;
+                let line = &mut self.text.buf.lines[cursor.line];
+                let mut cur = line.text().to_string();
+                cursor.index = cur.len();
+                cur.push_str(&add);
+                line.set_text(cur, line.ending(), line.attrs_list().clone());
+            } else {
+                let line = &mut self.text.buf.lines[cursor.line];
+                let mut text = line.text().to_string();
+                let idx = text.floor_char_boundary(cursor.index - 1);
+                text.remove(idx);
+                line.set_text(text, line.ending(), line.attrs_list().clone());
+                cursor.index = idx;
+            }
+        }
+    }
+
+    pub fn delete(&mut self) {
+        if let Some(cursor) = &mut self.text.cursor {
+            let line = &mut self.text.buf.lines[cursor.line];
+            if cursor.index == line.text().len() {
+                if cursor.line == self.text.buf.lines.len() - 1 {
+                    return;
+                }
+                let add = self.text.buf.lines.remove(cursor.line + 1).into_text();
+                let line = &mut self.text.buf.lines[cursor.line];
+                let mut cur = line.text().to_string();
+                cur.push_str(&add);
+                line.set_text(cur, line.ending(), line.attrs_list().clone());
+            } else {
+                let mut text = line.text().to_string();
+                text.remove(cursor.index);
+                line.set_text(text, line.ending(), line.attrs_list().clone());
+            }
+        }
+        if let Some(cursor) = self.text.cursor {
+            let line = &mut self.text.buf.lines[cursor.line];
+            let mut text = line.text().to_string();
+            text.remove(cursor.index);
+            line.set_text(text, line.ending(), line.attrs_list().clone());
+        }
+    }
+
+    pub fn select(&mut self, pos: Vec2, size: Vec2) {
+        let pos = pos - self.text.region().top_left.to_size(size);
+        self.text.cursor = self.text.buf.hit(pos.x, pos.y);
+    }
+
+    pub fn deselect(&mut self) {
+        self.text.cursor = None;
+    }
+}
+
+impl<Ctx> FnOnce<(&mut Ui<Ctx>,)> for TextEditBuilder {
+    type Output = TextEdit;
+
+    extern "rust-call" fn call_once(self, args: (&mut Ui<Ctx>,)) -> Self::Output {
+        let mut text = TextEdit {
+            buf: TextBuffer::new_empty(Metrics::new(self.attrs.font_size, self.attrs.line_height)),
+            attrs: self.attrs,
+            align: self.align,
+            cursor: None,
+            size: Vec2::ZERO,
+        };
+        text.buf.set_text(
+            &mut args.0.text.font_system,
+            &self.content,
+            &Attrs::new(),
+            Shaping::Advanced,
+        );
+        self.attrs
+            .apply(&mut args.0.text.font_system, &mut text.buf);
+        text
+    }
+}
+
+pub fn text_edit(content: impl Into<String>) -> TextEditBuilder {
+    TextEditBuilder {
+        content: content.into(),
+        attrs: TextAttrs::default(),
+        align: Align::Center,
+    }
+}