chore: update text input

crates/ui/src/input/text_wrapper.rs

@@ -0,0 +1,72 @@
+use std::ops::Range;
+
+use gpui::{App, Font, LineFragment, Pixels, SharedString};
+
+/// Used to prepare the text with soft_wrap to be get lines to displayed in the TextArea
+///
+/// After use lines to calculate the scroll size of the TextArea
+pub(super) struct TextWrapper {
+    pub(super) text: SharedString,
+    /// The wrapped lines, value is start and end index of the line (by split \n).
+    pub(super) wrapped_lines: Vec<Range<usize>>,
+    pub(super) font: Font,
+    pub(super) font_size: Pixels,
+    /// If is none, it means the text is not wrapped
+    pub(super) wrap_width: Option<Pixels>,
+}
+
+#[allow(unused)]
+impl TextWrapper {
+    pub(super) fn new(font: Font, font_size: Pixels, wrap_width: Option<Pixels>) -> Self {
+        Self {
+            text: SharedString::default(),
+            font,
+            font_size,
+            wrap_width,
+            wrapped_lines: Vec::new(),
+        }
+    }
+
+    pub(super) fn set_wrap_width(&mut self, wrap_width: Option<Pixels>, cx: &mut App) {
+        if self.wrap_width == wrap_width {
+            return;
+        }
+
+        self.wrap_width = wrap_width;
+        self.update(self.text.clone(), cx);
+    }
+
+    pub(super) fn set_font(&mut self, font: Font, cx: &mut App) {
+        self.font = font;
+        self.update(self.text.clone(), cx);
+    }
+
+    pub(super) fn update(&mut self, text: SharedString, cx: &mut App) {
+        let mut wrapped_lines = vec![];
+        let wrap_width = self.wrap_width.unwrap_or(Pixels::MAX);
+        let mut line_wrapper = cx
+            .text_system()
+            .line_wrapper(self.font.clone(), self.font_size);
+
+        for line in text.lines() {
+            let mut prev_boundary_ix = 0;
+            for boundary in line_wrapper.wrap_line(&[LineFragment::text(line)], wrap_width) {
+                wrapped_lines.push(prev_boundary_ix..boundary.ix);
+                prev_boundary_ix = boundary.ix;
+            }
+
+            // Reset of the line
+            if !line[prev_boundary_ix..].is_empty() || prev_boundary_ix == 0 {
+                wrapped_lines.push(prev_boundary_ix..line.len());
+            }
+        }
+
+        // Add last empty line.
+        if text.chars().last().unwrap_or('\n') == '\n' {
+            wrapped_lines.push(text.len()..text.len());
+        }
+
+        self.text = text;
+        self.wrapped_lines = wrapped_lines;
+    }
+}