[codex] Add full-page render debug command

README.md

@@ -26,6 +26,15 @@ cargo install --path .
 glass <notes-directory>
 ```
 
+Render a full ANSI debug snapshot without opening the interactive editor:
+
+```bash
+glass --render [--width 100] [--height rows] <path>
+```
+
+`--width` defaults to 100 columns. When `--height` is omitted, Glass renders the
+entire document followed by the status bar.
+
 ## Keybindings
 
 ### Normal mode

src/debug_render.rs

@@ -0,0 +1,240 @@
+use std::path::PathBuf;
+
+use anyhow::Result;
+use ratatui::{
+    Terminal,
+    backend::TestBackend,
+    layout::Rect,
+    style::{Color, Modifier},
+};
+
+use crate::{
+    app::App,
+    editor::render::{visible_rows, wrap_line},
+    markdown::{highlight::concealed_wrap_line, table::TableLayout},
+    ui,
+};
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+struct CellStyle {
+    fg: Color,
+    bg: Color,
+    modifier: Modifier,
+}
+
+impl Default for CellStyle {
+    fn default() -> Self {
+        Self {
+            fg: Color::Reset,
+            bg: Color::Reset,
+            modifier: Modifier::empty(),
+        }
+    }
+}
+
+pub fn render_path_to_ansi(
+    notes_dir: PathBuf,
+    initial_file: Option<PathBuf>,
+    width: u16,
+    height: Option<u16>,
+) -> Result<String> {
+    let mut app = App::new(notes_dir, initial_file)?;
+    let width = width.max(1);
+    let height = height.unwrap_or_else(|| full_render_height(&app, width));
+    let backend = TestBackend::new(width, height.max(2));
+    let mut terminal = Terminal::new(backend)?;
+    terminal.draw(|frame| ui::draw(frame, &mut app))?;
+    Ok(buffer_to_ansi(terminal.backend().buffer()))
+}
+
+fn full_render_height(app: &App, width: u16) -> u16 {
+    let editor_area = Rect {
+        x: 0,
+        y: 0,
+        width,
+        height: 1,
+    };
+    let page = ui::editor::page_area(editor_area);
+    let gutter_width = (app.buffer.line_count().to_string().len() + 1).max(1);
+    let text_width = page.width.saturating_sub(gutter_width as u16).max(1) as usize;
+    let table_layout = TableLayout::new(&app.buffer);
+    let rows = visible_rows(
+        &app.buffer,
+        0,
+        0,
+        usize::MAX,
+        text_width,
+        |line_num, text, w| {
+            if line_num == app.cursor.line {
+                wrap_line(text, w)
+            } else if table_layout.is_table_row(line_num) {
+                table_layout.wrap_line(line_num, text, w)
+            } else {
+                concealed_wrap_line(text, w)
+            }
+        },
+    );
+    rows.len().saturating_add(1).min(u16::MAX as usize) as u16
+}
+
+fn buffer_to_ansi(buffer: &ratatui::buffer::Buffer) -> String {
+    let mut out = String::new();
+    let area = buffer.area;
+    for y in area.top()..area.bottom() {
+        let mut current = CellStyle::default();
+        for x in area.left()..area.right() {
+            let Some(cell) = buffer.cell((x, y)) else {
+                continue;
+            };
+            let next = CellStyle {
+                fg: cell.fg,
+                bg: cell.bg,
+                modifier: cell.modifier,
+            };
+            if next != current {
+                out.push_str(&style_ansi(next));
+                current = next;
+            }
+            out.push_str(cell.symbol());
+        }
+        out.push_str("\x1b[0m");
+        if y + 1 < area.bottom() {
+            out.push('\n');
+        }
+    }
+    out
+}
+
+fn style_ansi(style: CellStyle) -> String {
+    let mut sequence = String::from("\x1b[0m");
+    sequence.push_str(&fg_ansi(style.fg));
+    sequence.push_str(&bg_ansi(style.bg));
+    if style.modifier.contains(Modifier::BOLD) {
+        sequence.push_str("\x1b[1m");
+    }
+    if style.modifier.contains(Modifier::DIM) {
+        sequence.push_str("\x1b[2m");
+    }
+    if style.modifier.contains(Modifier::ITALIC) {
+        sequence.push_str("\x1b[3m");
+    }
+    if style.modifier.contains(Modifier::UNDERLINED) {
+        sequence.push_str("\x1b[4m");
+    }
+    if style.modifier.contains(Modifier::REVERSED) {
+        sequence.push_str("\x1b[7m");
+    }
+    if style.modifier.contains(Modifier::CROSSED_OUT) {
+        sequence.push_str("\x1b[9m");
+    }
+    sequence
+}
+
+fn fg_ansi(color: Color) -> String {
+    color_ansi(color, true)
+}
+
+fn bg_ansi(color: Color) -> String {
+    color_ansi(color, false)
+}
+
+fn color_ansi(color: Color, foreground: bool) -> String {
+    let base = if foreground { 30 } else { 40 };
+    let bright_base = if foreground { 90 } else { 100 };
+    match color {
+        Color::Reset => format!("\x1b[{}m", if foreground { 39 } else { 49 }),
+        Color::Black => format!("\x1b[{base}m"),
+        Color::Red => format!("\x1b[{}m", base + 1),
+        Color::Green => format!("\x1b[{}m", base + 2),
+        Color::Yellow => format!("\x1b[{}m", base + 3),
+        Color::Blue => format!("\x1b[{}m", base + 4),
+        Color::Magenta => format!("\x1b[{}m", base + 5),
+        Color::Cyan => format!("\x1b[{}m", base + 6),
+        Color::Gray | Color::White => format!("\x1b[{}m", base + 7),
+        Color::DarkGray => format!("\x1b[{bright_base}m"),
+        Color::LightRed => format!("\x1b[{}m", bright_base + 1),
+        Color::LightGreen => format!("\x1b[{}m", bright_base + 2),
+        Color::LightYellow => format!("\x1b[{}m", bright_base + 3),
+        Color::LightBlue => format!("\x1b[{}m", bright_base + 4),
+        Color::LightMagenta => format!("\x1b[{}m", bright_base + 5),
+        Color::LightCyan => format!("\x1b[{}m", bright_base + 6),
+        Color::Rgb(r, g, b) => {
+            format!("\x1b[{};2;{r};{g};{b}m", if foreground { 38 } else { 48 })
+        }
+        Color::Indexed(index) => {
+            format!("\x1b[{};5;{index}m", if foreground { 38 } else { 48 })
+        }
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use anyhow::Context;
+    use std::fs;
+
+    #[test]
+    fn render_full_height_includes_entire_file_and_status_bar() -> Result<()> {
+        let dir = std::env::temp_dir().join(format!("glass-render-test-{}", std::process::id()));
+        fs::create_dir_all(&dir)?;
+        let file = dir.join("note.md");
+        fs::write(&file, "one\ntwo\nthree\n")?;
+
+        let ansi = render_path_to_ansi(dir.clone(), Some(file), 80, None)?;
+
+        assert!(ansi.contains("one"));
+        assert!(ansi.contains("two"));
+        assert!(ansi.contains("three"));
+        assert!(ansi.contains(" NORMAL  note.md"));
+
+        fs::remove_dir_all(dir).context("failed to clean render test directory")?;
+        Ok(())
+    }
+
+    #[test]
+    fn render_height_can_clip_document_but_keeps_status_bar() -> Result<()> {
+        let dir =
+            std::env::temp_dir().join(format!("glass-render-clip-test-{}", std::process::id()));
+        fs::create_dir_all(&dir)?;
+        let file = dir.join("note.md");
+        fs::write(&file, "one\ntwo\nthree\n")?;
+
+        let ansi = render_path_to_ansi(dir.clone(), Some(file), 80, Some(2))?;
+
+        assert!(ansi.contains("one"));
+        assert!(!ansi.contains("three"));
+        assert!(ansi.contains(" NORMAL  note.md"));
+
+        fs::remove_dir_all(dir).context("failed to clean render test directory")?;
+        Ok(())
+    }
+
+    #[test]
+    fn render_height_has_status_bar_even_when_too_small() -> Result<()> {
+        let dir =
+            std::env::temp_dir().join(format!("glass-render-small-test-{}", std::process::id()));
+        fs::create_dir_all(&dir)?;
+        let file = dir.join("note.md");
+        fs::write(&file, "one\n")?;
+
+        let ansi = render_path_to_ansi(dir.clone(), Some(file), 80, Some(1))?;
+
+        assert!(ansi.contains(" NORMAL  note.md"));
+
+        fs::remove_dir_all(dir).context("failed to clean render test directory")?;
+        Ok(())
+    }
+
+    #[test]
+    fn style_ansi_includes_rgb_and_modifiers() {
+        let ansi = style_ansi(CellStyle {
+            fg: Color::Rgb(1, 2, 3),
+            bg: Color::Reset,
+            modifier: Modifier::BOLD | Modifier::UNDERLINED,
+        });
+
+        assert!(ansi.contains("\x1b[38;2;1;2;3m"));
+        assert!(ansi.contains("\x1b[1m"));
+        assert!(ansi.contains("\x1b[4m"));
+    }
+}