feat(tui/image): render view image as card

code-rs/tui/src/history_cell/image.rs

@@ -1,5 +1,22 @@
+use super::card_style::{
+    ansi16_inverse_color,
+    browser_card_style,
+    fill_card_background,
+    hint_text_style,
+    primary_text_style,
+    rows_to_lines,
+    secondary_text_style,
+    title_text_style,
+    truncate_with_ellipsis,
+    CardRow,
+    CardSegment,
+    CardStyle,
+    CARD_ACCENT_WIDTH,
+};
 use super::*;
+use crate::colors;
 use crate::history::state::ImageRecord;
+use crate::theme::{palette_mode, PaletteMode};
 use code_protocol::num_format::format_with_separators;
 use ::image::ImageReader;
 use ::image::image_dimensions;
@@ -11,6 +28,29 @@ use std::cell::RefCell;
 use std::path::Path;
 use std::path::PathBuf;
 use std::rc::Rc;
+use unicode_width::UnicodeWidthChar;
+
+const BORDER_TOP: &str = "╭─";
+const BORDER_BODY: &str = "│";
+const BORDER_BOTTOM: &str = "╰─";
+
+const DEFAULT_TEXT_INDENT: usize = 2;
+const TEXT_RIGHT_PADDING: usize = 2;
+const IMAGE_GAP: usize = 2;
+const IMAGE_LEFT_PAD: usize = 1;
+const IMAGE_MIN_WIDTH: usize = 18;
+const IMAGE_MAX_WIDTH: usize = 64;
+const MIN_TEXT_WIDTH: usize = 28;
+const MIN_IMAGE_ROWS: usize = 4;
+const MAX_IMAGE_ROWS: usize = 60;
+const HINT_TEXT: &str = "Image output";
+
+struct ImagePreviewLayout {
+    start_row: usize,
+    height_rows: usize,
+    width_cols: usize,
+    indent_cols: usize,
+}
 
 pub(crate) struct ImageOutputCell {
     record: ImageRecord,
@@ -52,27 +92,491 @@ impl ImageOutputCell {
         picker_ref.as_ref().unwrap().clone()
     }
 
-    fn image_rows_for_width(&self, width: u16) -> Option<u16> {
-        const MIN_IMAGE_ROWS: usize = 4;
-        const MAX_IMAGE_ROWS: usize = 60;
-        let path = self.image_path()?;
-        if width == 0 || !path.exists() {
+    fn accent_style(style: &CardStyle) -> Style {
+        if palette_mode() == PaletteMode::Ansi16 {
+            return Style::default().fg(ansi16_inverse_color());
+        }
+        let dim = colors::mix_toward(style.accent_fg, style.text_secondary, 0.85);
+        Style::default().fg(dim)
+    }
+
+    fn display_label(&self) -> String {
+        if let Some(alt) = self
+            .record
+            .alt_text
+            .as_ref()
+            .map(|value| value.trim())
+            .filter(|value| !value.is_empty())
+        {
+            return alt.to_string();
+        }
+        if let Some(path) = self.record.source_path.as_ref() {
+            if let Some(name) = path.file_name().and_then(|name| name.to_str()) {
+                if !name.trim().is_empty() {
+                    return name.to_string();
+                }
+            }
+            return path.display().to_string();
+        }
+        "Image".to_string()
+    }
+
+    fn header_title_text(&self) -> String {
+        let label = self.display_label();
+        if label.eq_ignore_ascii_case("image") {
+            "Image".to_string()
+        } else {
+            format!("Image: {label}")
+        }
+    }
+
+    fn metadata_lines(&self) -> Vec<String> {
+        let record = &self.record;
+        let width = record.width;
+        let height = record.height;
+        let mut lines = Vec::new();
+        lines.push(format!("Dimensions: {width}x{height} px"));
+        if let Some(mime) = record
+            .mime_type
+            .as_ref()
+            .map(|value| value.trim())
+            .filter(|value| !value.is_empty())
+        {
+            lines.push(format!("Type: {mime}"));
+        }
+        if let Some(byte_len) = record.byte_len {
+            let size = format_with_separators(u64::from(byte_len));
+            lines.push(format!("Size: {size} bytes"));
+        }
+        if let Some(alt) = record
+            .alt_text
+            .as_ref()
+            .map(|value| value.trim())
+            .filter(|value| !value.is_empty())
+        {
+            lines.push(format!("Alt: {alt}"));
+        }
+        if let Some(path) = record.source_path.as_ref() {
+            lines.push(format!("Source: {}", path.display()));
+        }
+        if let Some(hash) = record.sha256.as_ref() {
+            let short = if hash.len() > 12 {
+                format!("{}…", &hash[..12])
+            } else {
+                hash.clone()
+            };
+            lines.push(format!("SHA256: {short}"));
+        }
+        lines
+    }
+
+    fn top_border_row(&self, body_width: usize, style: &CardStyle) -> CardRow {
+        let mut segments = Vec::new();
+        if body_width == 0 {
+            return CardRow::new(
+                BORDER_TOP.to_string(),
+                Self::accent_style(style),
+                segments,
+                None,
+            );
+        }
+
+        let title_style = if palette_mode() == PaletteMode::Ansi16 {
+            Style::default().fg(ansi16_inverse_color())
+        } else {
+            title_text_style(style)
+        };
+
+        segments.push(CardSegment::new(" ".to_string(), title_style));
+        let remaining = body_width.saturating_sub(1);
+        let text = truncate_with_ellipsis(self.header_title_text().as_str(), remaining);
+        if !text.is_empty() {
+            segments.push(CardSegment::new(text, title_style));
+        }
+        CardRow::new(BORDER_TOP.to_string(), Self::accent_style(style), segments, None)
+    }
+
+    fn blank_border_row(&self, body_width: usize, style: &CardStyle) -> CardRow {
+        CardRow::new(
+            BORDER_BODY.to_string(),
+            Self::accent_style(style),
+            vec![CardSegment::new(" ".repeat(body_width), Style::default())],
+            None,
+        )
+    }
+
+    fn body_text_row(
+        &self,
+        text: impl Into<String>,
+        body_width: usize,
+        style: &CardStyle,
+        text_style: Style,
+        indent_cols: usize,
+        right_padding_cols: usize,
+    ) -> CardRow {
+        if body_width == 0 {
+            return CardRow::new(BORDER_BODY.to_string(), Self::accent_style(style), Vec::new(), None);
+        }
+        let indent = indent_cols.min(body_width.saturating_sub(1));
+        let available = body_width.saturating_sub(indent);
+        let mut segments = Vec::new();
+        if indent > 0 {
+            segments.push(CardSegment::new(" ".repeat(indent), Style::default()));
+        }
+        let text: String = text.into();
+        if available == 0 {
+            return CardRow::new(BORDER_BODY.to_string(), Self::accent_style(style), segments, None);
+        }
+        let usable_width = available.saturating_sub(right_padding_cols);
+        let display = if usable_width == 0 {
+            String::new()
+        } else {
+            truncate_with_ellipsis(text.as_str(), usable_width)
+        };
+        segments.push(CardSegment::new(display, text_style));
+        if right_padding_cols > 0 && available > 0 {
+            let pad = right_padding_cols.min(available);
+            segments.push(CardSegment::new(" ".repeat(pad), Style::default()));
+        }
+        CardRow::new(BORDER_BODY.to_string(), Self::accent_style(style), segments, None)
+    }
+
+    fn bottom_border_row(&self, body_width: usize, style: &CardStyle) -> CardRow {
+        let text = truncate_with_ellipsis(HINT_TEXT, body_width);
+        let hint_style = if palette_mode() == PaletteMode::Ansi16 {
+            Style::default().fg(ansi16_inverse_color())
+        } else {
+            hint_text_style(style)
+        };
+        let segment = CardSegment::new(text, hint_style);
+        CardRow::new(
+            BORDER_BOTTOM.to_string(),
+            Self::accent_style(style),
+            vec![segment],
+            None,
+        )
+    }
+
+    fn build_card_rows(
+        &self,
+        width: u16,
+        style: &CardStyle,
+    ) -> (Vec<CardRow>, Option<ImagePreviewLayout>) {
+        if width == 0 {
+            return (Vec::new(), None);
+        }
+
+        let accent_width = CARD_ACCENT_WIDTH.min(width as usize);
+        let body_width = width
+            .saturating_sub(accent_width as u16)
+            .saturating_sub(1) as usize;
+        if body_width == 0 {
+            return (Vec::new(), None);
+        }
+
+        let mut rows: Vec<CardRow> = Vec::new();
+        rows.push(self.top_border_row(body_width, style));
+        rows.push(self.blank_border_row(body_width, style));
+
+        let mut image_layout = self.compute_image_layout(body_width);
+        let indent_cols = image_layout
+            .as_ref()
+            .map(|layout| layout.indent_cols)
+            .unwrap_or(DEFAULT_TEXT_INDENT);
+        let indent_cols = indent_cols.min(body_width.saturating_sub(1));
+        let right_padding = TEXT_RIGHT_PADDING.min(body_width);
+
+        let content_start = rows.len();
+
+        rows.push(self.body_text_row(
+            "Details",
+            body_width,
+            style,
+            primary_text_style(style),
+            indent_cols,
+            right_padding,
+        ));
+
+        let details = self.metadata_lines();
+        if details.is_empty() {
+            for wrapped in wrap_card_lines(
+                "No image metadata available",
+                body_width,
+                indent_cols,
+                right_padding,
+            ) {
+                rows.push(self.body_text_row(
+                    wrapped,
+                    body_width,
+                    style,
+                    secondary_text_style(style),
+                    indent_cols,
+                    right_padding,
+                ));
+            }
+        } else {
+            for detail in details {
+                for wrapped in wrap_card_lines(
+                    detail.as_str(),
+                    body_width,
+                    indent_cols,
+                    right_padding,
+                ) {
+                    rows.push(self.body_text_row(
+                        wrapped,
+                        body_width,
+                        style,
+                        secondary_text_style(style),
+                        indent_cols,
+                        right_padding,
+                    ));
+                }
+            }
+        }
+
+        if let Some(layout) = image_layout.as_mut() {
+            layout.start_row = content_start;
+            let existing = rows.len().saturating_sub(content_start);
+            if existing < layout.height_rows {
+                let missing = layout.height_rows - existing;
+                for _ in 0..missing {
+                    rows.push(self.body_text_row(
+                        "",
+                        body_width,
+                        style,
+                        Style::default(),
+                        indent_cols,
+                        right_padding,
+                    ));
+                }
+            }
+        }
+
+        rows.push(self.blank_border_row(body_width, style));
+        rows.push(self.bottom_border_row(body_width, style));
+
+        (rows, image_layout)
+    }
+
+    fn compute_image_layout(&self, body_width: usize) -> Option<ImagePreviewLayout> {
+        if self.image_path().is_none() {
             return None;
         }
+
+        if body_width
+            < IMAGE_LEFT_PAD + IMAGE_MIN_WIDTH + IMAGE_GAP + MIN_TEXT_WIDTH + TEXT_RIGHT_PADDING
+        {
+            return None;
+        }
+
+        let max_image = body_width
+            .saturating_sub(IMAGE_LEFT_PAD + MIN_TEXT_WIDTH + IMAGE_GAP + TEXT_RIGHT_PADDING);
+        if max_image < IMAGE_MIN_WIDTH {
+            return None;
+        }
+
+        let mut image_cols = max_image;
+        if image_cols > IMAGE_MAX_WIDTH {
+            image_cols = IMAGE_MAX_WIDTH;
+        }
+        if image_cols < IMAGE_MIN_WIDTH {
+            image_cols = IMAGE_MIN_WIDTH;
+        }
+
+        let rows = self.compute_image_rows(image_cols)?;
+        Some(ImagePreviewLayout {
+            start_row: 0,
+            height_rows: rows,
+            width_cols: image_cols,
+            indent_cols: IMAGE_LEFT_PAD + image_cols + IMAGE_GAP,
+        })
+    }
+
+    fn compute_image_rows(&self, image_cols: usize) -> Option<usize> {
+        if image_cols == 0 {
+            return None;
+        }
+        let path = self.image_path()?;
         let picker = self.ensure_picker();
         let (cell_w, cell_h) = picker.font_size();
         if cell_w == 0 || cell_h == 0 {
-            return Some(MIN_IMAGE_ROWS as u16);
+            return Some(MIN_IMAGE_ROWS);
         }
+
         let (img_w, img_h) = match image_dimensions(path) {
             Ok((w, h)) if w > 0 && h > 0 => (w, h),
-            _ => return Some(MIN_IMAGE_ROWS as u16),
+            _ => return Some(MIN_IMAGE_ROWS),
         };
-        let cols = width as u32;
+
+        let cols = image_cols as u32;
         let rows_by_w = (cols * cell_w as u32 * img_h) as f64
             / (img_w * cell_h as u32) as f64;
         let rows = rows_by_w.ceil().max(1.0) as usize;
-        Some(rows.clamp(MIN_IMAGE_ROWS, MAX_IMAGE_ROWS) as u16)
+        Some(rows.clamp(MIN_IMAGE_ROWS, MAX_IMAGE_ROWS))
+    }
+
+    fn render_card(&self, area: Rect, buf: &mut Buffer, skip_rows: u16) {
+        if area.width <= 2 || area.height == 0 {
+            return;
+        }
+
+        let style = browser_card_style();
+        let draw_width = area.width - 2;
+        let render_area = Rect {
+            width: draw_width,
+            ..area
+        };
+
+        fill_card_background(buf, render_area, &style);
+        let (rows, preview_layout) = self.build_card_rows(render_area.width, &style);
+        if rows.is_empty() {
+            self.render_plain_summary(area, buf, skip_rows);
+            return;
+        }
+        let lines = rows_to_lines(&rows, &style, render_area.width);
+        let text = Text::from(lines);
+
+        Paragraph::new(text)
+            .wrap(Wrap { trim: false })
+            .scroll((skip_rows, 0))
+            .render(render_area, buf);
+
+        if let Some(layout) = preview_layout.as_ref() {
+            if let Some(path) = self.image_path() {
+                self.render_image_preview(render_area, buf, skip_rows, layout, path);
+            }
+        }
+
+        let clear_start = area.x + draw_width;
+        let clear_end = area.x + area.width;
+        for x in clear_start..clear_end {
+            for row in 0..area.height {
+                let cell = &mut buf[(x, area.y + row)];
+                cell.set_symbol(" ");
+                cell.set_bg(crate::colors::background());
+            }
+        }
+    }
+
+    fn render_image_preview(
+        &self,
+        area: Rect,
+        buf: &mut Buffer,
+        skip_rows: u16,
+        layout: &ImagePreviewLayout,
+        path: &Path,
+    ) {
+        let accent_width = CARD_ACCENT_WIDTH.min(area.width as usize) as u16;
+        if accent_width >= area.width {
+            return;
+        }
+
+        let viewport_top = skip_rows as usize;
+        let viewport_bottom = viewport_top + area.height as usize;
+        let shot_top = layout.start_row;
+        let shot_bottom = layout.start_row + layout.height_rows;
+
+        if shot_bottom <= viewport_top || shot_top >= viewport_bottom {
+            return;
+        }
+
+        let visible_top = shot_top.max(viewport_top);
+        let visible_bottom = shot_bottom.min(viewport_bottom);
+        if visible_bottom <= visible_top {
+            return;
+        }
+
+        let body_width = area.width.saturating_sub(accent_width);
+        if body_width == 0 {
+            return;
+        }
+
+        let left_pad = IMAGE_LEFT_PAD.min(body_width as usize) as u16;
+        if body_width <= left_pad {
+            return;
+        }
+
+        let usable_width = body_width.saturating_sub(left_pad);
+        let image_width = layout.width_cols.min(usable_width as usize) as u16;
+        if image_width == 0 {
+            return;
+        }
+
+        let rows_to_copy = (visible_bottom - visible_top) as u16;
+        if rows_to_copy == 0 {
+            return;
+        }
+
+        let dest_x = area.x + accent_width + left_pad;
+        let dest_y = area.y + (visible_top - viewport_top) as u16;
+
+        if !path.exists() {
+            let placeholder_area = Rect { x: dest_x, y: dest_y, width: image_width, height: rows_to_copy };
+            self.render_image_placeholder(path, placeholder_area, buf);
+            return;
+        }
+
+        let full_height = layout.height_rows as u16;
+        if full_height == 0 {
+            return;
+        }
+
+        let offscreen = match self.render_image_buffer(path, image_width, full_height) {
+            Ok(buffer) => buffer,
+            Err(_) => {
+                let placeholder_area = Rect { x: dest_x, y: dest_y, width: image_width, height: rows_to_copy };
+                self.render_image_placeholder(path, placeholder_area, buf);
+                return;
+            }
+        };
+
+        let src_start_row = (visible_top - shot_top) as u16;
+        let area_bottom = area.y + area.height;
+        let area_right = area.x + area.width;
+
+        for row in 0..rows_to_copy {
+            let dest_row = dest_y + row;
+            if dest_row >= area_bottom {
+                break;
+            }
+            let src_row = src_start_row + row;
+            for col in 0..image_width {
+                let dest_col = dest_x + col;
+                if dest_col >= area_right {
+                    break;
+                }
+                let Some(src_cell) = offscreen.cell((col, src_row)) else { continue; };
+                if let Some(dest_cell) = buf.cell_mut((dest_col, dest_row)) {
+                    *dest_cell = src_cell.clone();
+                }
+            }
+        }
+    }
+
+    fn render_image_placeholder(&self, path: &Path, area: Rect, buf: &mut Buffer) {
+        use ratatui::style::{Modifier, Style};
+        use ratatui::widgets::{Block, Borders};
+
+        let filename = path
+            .file_name()
+            .and_then(|n| n.to_str())
+            .unwrap_or("image");
+        let placeholder_text = format!("Image:\n{filename}");
+
+        let block = Block::default()
+            .borders(Borders::ALL)
+            .border_style(Style::default().fg(colors::info()))
+            .title("Image");
+        let inner = block.inner(area);
+        block.render(area, buf);
+        Paragraph::new(placeholder_text)
+            .style(
+                Style::default()
+                    .fg(colors::text_dim())
+                    .add_modifier(Modifier::ITALIC),
+            )
+            .wrap(Wrap { trim: true })
+            .render(inner, buf);
     }
 
     fn render_image_buffer(&self, path: &Path, width: u16, height: u16) -> Result<Buffer, ()> {
@@ -112,9 +616,9 @@ impl ImageOutputCell {
         Ok(())
     }
 
-    fn render_text_only(&self, area: Rect, buf: &mut Buffer, skip_rows: u16) {
-        let cell_bg = crate::colors::background();
-        let bg_style = Style::default().bg(cell_bg).fg(crate::colors::text());
+    fn render_plain_summary(&self, area: Rect, buf: &mut Buffer, skip_rows: u16) {
+        let cell_bg = colors::background();
+        let bg_style = Style::default().bg(cell_bg).fg(colors::text());
         fill_rect(buf, area, Some(' '), bg_style);
         let lines = self.display_lines_trimmed();
         let text = Text::from(lines);
@@ -140,108 +644,129 @@ impl HistoryCell for ImageOutputCell {
     }
 
     fn display_lines(&self) -> Vec<Line<'static>> {
-        let record = &self.record;
-        let mut descriptors = vec![format!("{}x{} px", record.width, record.height)];
-        if let Some(mime) = &record.mime_type {
-            descriptors.push(mime.clone());
-        }
-        if let Some(byte_len) = record.byte_len {
-            descriptors.push(format!(
-                "{} bytes",
-                format_with_separators(u64::from(byte_len))
-            ));
-        }
-        let summary = format!("tool result ({})", descriptors.join(", "));
+        let label = self.display_label();
+        let summary = if label.eq_ignore_ascii_case("image") {
+            "Image output".to_string()
+        } else {
+            format!("Image output: {label}")
+        };
 
         let mut lines = vec![Line::from(summary)];
-        if let Some(alt) = record.alt_text.as_ref() {
-            if !alt.is_empty() {
-                lines.push(Line::from(format!("alt: {alt}")));
-            }
-        }
-        if let Some(path) = record.source_path.as_ref() {
-            lines.push(Line::from(format!("source: {}", path.display())));
-        }
-        if let Some(hash) = record.sha256.as_ref() {
-            let short = if hash.len() > 12 {
-                format!("{}…", &hash[..12])
-            } else {
-                hash.clone()
-            };
-            lines.push(Line::from(format!("sha256: {short}")));
+        for line in self.metadata_lines() {
+            lines.push(Line::from(line));
         }
         lines.push(Line::from(""));
         lines
     }
 
     fn desired_height(&self, width: u16) -> u16 {
-        let image_rows = self.image_rows_for_width(width).unwrap_or(0);
-        let lines = self.display_lines_trimmed();
-        let text_height = Paragraph::new(Text::from(lines))
-            .wrap(Wrap { trim: false })
-            .line_count(width) as u16;
-        image_rows.saturating_add(text_height)
+        let style = browser_card_style();
+        let trimmed_width = width.saturating_sub(2);
+        if trimmed_width == 0 {
+            return 0;
+        }
+        let (rows, _) = self.build_card_rows(trimmed_width, &style);
+        rows.len().max(1) as u16
     }
 
     fn has_custom_render(&self) -> bool {
-        self.image_path().is_some()
+        true
     }
 
     fn custom_render_with_skip(&self, area: Rect, buf: &mut Buffer, skip_rows: u16) {
-        let Some(path) = self.image_path() else {
-            self.render_text_only(area, buf, skip_rows);
-            return;
-        };
-        let Some(image_rows) = self.image_rows_for_width(area.width) else {
-            self.render_text_only(area, buf, skip_rows);
-            return;
-        };
-
-        let cell_bg = crate::colors::background();
-        let bg_style = Style::default().bg(cell_bg).fg(crate::colors::text());
-        fill_rect(buf, area, Some(' '), bg_style);
-
-        let mut image_visible_rows = 0u16;
-        if skip_rows < image_rows {
-            image_visible_rows = (image_rows - skip_rows).min(area.height);
-            let offscreen = match self.render_image_buffer(path, area.width, image_rows) {
-                Ok(buffer) => buffer,
-                Err(_) => {
-                    self.render_text_only(area, buf, skip_rows);
-                    return;
-                }
-            };
-            let src_start = skip_rows;
-            for row in 0..image_visible_rows {
-                let dest_row = area.y + row;
-                let src_row = src_start + row;
-                for col in 0..area.width {
-                    let dest_col = area.x + col;
-                    let Some(src_cell) = offscreen.cell((col, src_row)) else {
-                        continue;
-                    };
-                    if let Some(dest_cell) = buf.cell_mut((dest_col, dest_row)) {
-                        *dest_cell = src_cell.clone();
-                    }
-                }
-            }
-        }
-
-        if area.height > image_visible_rows {
-            let text_area = Rect {
-                x: area.x,
-                y: area.y + image_visible_rows,
-                width: area.width,
-                height: area.height - image_visible_rows,
-            };
-            let text_scroll = skip_rows.saturating_sub(image_rows);
-            let lines = self.display_lines_trimmed();
-            let text = Text::from(lines);
-            Paragraph::new(text)
-                .wrap(Wrap { trim: false })
-                .scroll((text_scroll, 0))
-                .style(Style::default().bg(cell_bg))
-                .render(text_area, buf);
-        }
+        self.render_card(area, buf, skip_rows);
     }
 }
+
+fn wrap_card_lines(text: &str, body_width: usize, indent_cols: usize, right_padding: usize) -> Vec<String> {
+    let available = body_width
+        .saturating_sub(indent_cols)
+        .saturating_sub(right_padding);
+    if available == 0 {
+        return vec![String::new()];
+    }
+    wrap_line_to_width(text, available)
+}
+
+fn wrap_line_to_width(text: &str, width: usize) -> Vec<String> {
+    if width == 0 {
+        return vec![String::new()];
+    }
+    if text.trim().is_empty() {
+        return vec![String::new()];
+    }
+
+    let mut lines: Vec<String> = Vec::new();
+    let mut current = String::new();
+    let mut current_width = 0;
+
+    for word in text.split_whitespace() {
+        let mut word_parts = if string_display_width(word) > width {
+            split_long_card_word(word, width)
+        } else {
+            vec![word.to_string()]
+        };
+
+        for part in word_parts.drain(..) {
+            let part_width = string_display_width(part.as_str());
+            if current.is_empty() {
+                current.push_str(part.as_str());
+                current_width = part_width;
+            } else if current_width + 1 + part_width > width {
+                lines.push(current);
+                current = part.clone();
+                current_width = part_width;
+            } else {
+                current.push(' ');
+                current.push_str(part.as_str());
+                current_width += 1 + part_width;
+            }
+        }
+    }
+
+    if !current.is_empty() {
+        lines.push(current);
+    }
+
+    if lines.is_empty() {
+        lines.push(String::new());
+    }
+    lines
+}
+
+fn split_long_card_word(word: &str, width: usize) -> Vec<String> {
+    if width == 0 {
+        return vec![String::new()];
+    }
+
+    let mut parts = Vec::new();
+    let mut current = String::new();
+    let mut current_width = 0;
+
+    for ch in word.chars() {
+        let ch_width = UnicodeWidthChar::width(ch).unwrap_or(1);
+        if current_width + ch_width > width && !current.is_empty() {
+            parts.push(current);
+            current = String::new();
+            current_width = 0;
+        }
+        current.push(ch);
+        current_width += ch_width;
+    }
+
+    if !current.is_empty() {
+        parts.push(current);
+    }
+
+    if parts.is_empty() {
+        parts.push(String::new());
+    }
+    parts
+}
+
+fn string_display_width(text: &str) -> usize {
+    text
+        .chars()
+        .map(|ch| UnicodeWidthChar::width(ch).unwrap_or(0))
+        .sum()
+}