feat: Use eye-declare for more performant and flexible AI TUI (#3343)

This PR replaces the mess of custom rendering code in Atuin AI with
[eye-declare](https://github.com/BinaryMuse/eye-declare), and updates
the TUI to feel more terminal-native: output appears inline and persists
in scrollback, so you can scroll up and look at previous conversations
for reference.

The "review" state — which used to exist between the LLM generating a
response and the user either executing or following up — has been
removed; just start typing to follow up with the LLM, or press `enter`
at the empty input box to execute the suggested command.

<img width="1203" height="633" alt="image"
src="https://github.com/user-attachments/assets/159ee447-9a2a-4edd-b56e-a79bf1aaaa94"
/>

1 files changed, 0 insertions, 278 deletions

diff --git a/crates/atuin-ai/src/tui/terminal.rs b/crates/atuin-ai/src/tui/terminal.rs
deleted file mode 100644
index f8089323..00000000
--- a/crates/atuin-ai/src/tui/terminal.rs
+++ /dev/null
@@ -1,278 +0,0 @@
-use crossterm::{
-    cursor,
-    terminal::{disable_raw_mode, enable_raw_mode},
-};
-use eyre::{Context, Result, bail};
-use ratatui::{Terminal, TerminalOptions, Viewport, backend::CrosstermBackend, layout::Rect};
-use std::io::{IsTerminal, Stdout, stdout};
-
-/// Install a panic hook that ensures the terminal is restored to a usable state
-/// even if the application panics.
-///
-/// This must be called before creating the TerminalGuard to ensure proper cleanup
-/// during panics. The hook will:
-/// 1. Disable raw mode (restoring normal terminal behavior)
-/// 2. Call the original panic hook to display panic information
-///
-/// # Implementation Note
-/// This satisfies TUI-07: Terminal remains usable after panic by ensuring
-/// disable_raw_mode() is called before the panic message is displayed.
-pub fn install_panic_hook() {
-    let original_hook = std::panic::take_hook();
-    std::panic::set_hook(Box::new(move |panic_info| {
-        // Attempt to restore terminal - ignore errors since we're already panicking
-        let _ = disable_raw_mode();
-        // Call original hook to display panic with backtrace
-        original_hook(panic_info);
-    }));
-}
-
-/// Minimum viewport height
-const MIN_VIEWPORT_HEIGHT: u16 = 10;
-
-/// Margin to leave below viewport for shell prompt
-const VIEWPORT_BOTTOM_MARGIN: u16 = 2;
-
-/// Guards terminal lifecycle, ensuring proper setup and cleanup.
-///
-/// # Lifecycle
-/// - **Setup** (`new()`): Captures cursor position, enables raw mode, creates inline viewport
-/// - **Cleanup** (`Drop`): Clears terminal, disables raw mode
-///
-/// # Dynamic Viewport Sizing
-/// The viewport starts at 15 lines (enough for simple commands) and grows
-/// dynamically when content requires more space. Use `ensure_height()` before
-/// rendering to grow the viewport if needed.
-///
-/// # Safety Features
-/// - Non-TTY detection: Returns error early if stdout is not a terminal
-/// - Panic recovery: Works with `install_panic_hook()` to restore terminal after panic
-/// - Drop-based cleanup: Ensures terminal is restored on normal exit
-///
-/// # Example
-/// ```no_run
-/// use atuin_ai::tui::{install_panic_hook, TerminalGuard};
-///
-/// install_panic_hook(); // Once at program start
-/// let mut guard = TerminalGuard::new(true)?;
-/// let terminal = guard.terminal();
-/// // ... use terminal ...
-/// // Drop automatically cleans up
-/// # Ok::<(), eyre::Report>(())
-/// ```
-pub struct TerminalGuard {
-    terminal: Terminal<CrosstermBackend<Stdout>>,
-    anchor_col: u16,
-    keep_output: bool,
-    viewport_height: u16,
-    popup_mode: bool,
-}
-
-impl TerminalGuard {
-    /// Create a new TerminalGuard, initializing the terminal for inline TUI mode.
-    ///
-    /// # Arguments
-    /// * `keep_output` - If true, preserve TUI output on exit; if false, clear it
-    ///
-    /// # Process
-    /// 1. Check if stdout is a terminal (non-TTY detection)
-    /// 2. Capture cursor position for inline rendering anchor
-    /// 3. Enable raw mode for keyboard input
-    /// 4. Create terminal with inline viewport
-    ///
-    /// # Errors
-    /// - Returns error if stdout is not a terminal (e.g., piped or redirected)
-    /// - Returns error if terminal initialization fails
-    ///
-    /// # Implementation Note
-    /// Cursor position is captured BEFORE enabling raw mode because some terminals
-    /// may report position differently after raw mode is enabled.
-    pub fn new(keep_output: bool) -> Result<Self> {
-        // Non-TTY check: fail early if stdout is not a terminal
-        if !stdout().is_terminal() {
-            bail!(
-                "atuin-ai requires a terminal (TTY) but stdout is not a terminal. \
-                   This typically happens when output is piped or redirected."
-            );
-        }
-
-        // Get terminal size and calculate viewport height
-        let (_, term_height) = crossterm::terminal::size().unwrap_or((80, 24));
-        let viewport_height = term_height
-            .saturating_sub(VIEWPORT_BOTTOM_MARGIN)
-            .max(MIN_VIEWPORT_HEIGHT);
-
-        // Capture cursor position BEFORE raw mode for accurate anchor
-        let anchor_col = cursor::position().map(|(x, _)| x).unwrap_or(0);
-
-        // Enable raw mode for keyboard input
-        enable_raw_mode().context("failed to enable raw mode")?;
-
-        // Create terminal with fixed viewport based on terminal size
-        let backend = CrosstermBackend::new(stdout());
-        let terminal = Terminal::with_options(
-            backend,
-            TerminalOptions {
-                viewport: Viewport::Inline(viewport_height),
-            },
-        )
-        .context("failed to create terminal with inline viewport")?;
-
-        Ok(Self {
-            terminal,
-            anchor_col,
-            keep_output,
-            viewport_height,
-            popup_mode: false,
-        })
-    }
-
-    /// Create a new TerminalGuard for popup overlay mode.
-    ///
-    /// In popup mode:
-    /// - Raw mode is not managed (atuin-hex owns it)
-    /// - The viewport is a fixed rect positioned over existing terminal content
-    /// - The popup area is pre-cleared to prevent background bleed-through
-    /// - Drop does not clear the viewport or disable raw mode
-    pub fn new_popup(popup_rect: Rect, anchor_col: u16) -> Result<Self> {
-        // Pre-clear the popup area before creating the ratatui terminal.
-        // Ratatui's diff-based rendering won't write "default" (space) cells on
-        // the first frame because its previous buffer is also all-default. By
-        // writing spaces to the terminal now, we ensure those positions are
-        // visually blank even if ratatui skips them.
-        {
-            use crossterm::cursor::MoveTo;
-            use crossterm::execute;
-            use crossterm::style::{Attribute, SetAttribute};
-            use std::io::Write;
-
-            let mut out = stdout();
-            for row in popup_rect.y..popup_rect.y.saturating_add(popup_rect.height) {
-                let _ = execute!(
-                    out,
-                    MoveTo(popup_rect.x, row),
-                    SetAttribute(Attribute::Reset)
-                );
-                let _ = write!(out, "{:width$}", "", width = popup_rect.width as usize);
-            }
-            let _ = out.flush();
-        }
-
-        let backend = CrosstermBackend::new(stdout());
-        let terminal = Terminal::with_options(
-            backend,
-            TerminalOptions {
-                viewport: Viewport::Fixed(popup_rect),
-            },
-        )
-        .context("failed to create terminal with fixed viewport")?;
-
-        Ok(Self {
-            terminal,
-            anchor_col,
-            keep_output: false,
-            viewport_height: popup_rect.height,
-            popup_mode: true,
-        })
-    }
-
-    /// Returns the current viewport height.
-    ///
-    /// The viewport is fixed at creation time based on terminal size.
-    /// Content that exceeds this height will be scrolled automatically.
-    ///
-    /// The `_needed` parameter is kept for API compatibility but ignored -
-    /// we no longer attempt to resize the viewport dynamically since that
-    /// operation can fail unpredictably with inline viewports.
-    pub fn ensure_height(&mut self, _needed: u16) -> Result<u16> {
-        Ok(self.viewport_height)
-    }
-
-    /// Get the current viewport height.
-    pub fn viewport_height(&self) -> u16 {
-        self.viewport_height
-    }
-
-    /// Get mutable reference to the underlying terminal.
-    ///
-    /// Use this to perform rendering operations.
-    pub fn terminal(&mut self) -> &mut Terminal<CrosstermBackend<Stdout>> {
-        &mut self.terminal
-    }
-
-    /// Resize the popup viewport to a new rect.
-    ///
-    /// Creates a fresh terminal with the updated Fixed viewport. The caller
-    /// is responsible for pre-clearing any newly exposed rows before calling
-    /// this (see `PopupState::grow_to`).
-    pub fn resize_popup(&mut self, new_rect: Rect) -> Result<()> {
-        self.viewport_height = new_rect.height;
-        let backend = CrosstermBackend::new(stdout());
-        self.terminal = Terminal::with_options(
-            backend,
-            TerminalOptions {
-                viewport: Viewport::Fixed(new_rect),
-            },
-        )
-        .context("failed to resize popup terminal")?;
-        Ok(())
-    }
-
-    /// Get the anchor column where the inline UI should be positioned.
-    ///
-    /// This is the column position where the cursor was located when
-    /// the terminal was initialized.
-    pub fn anchor_col(&self) -> u16 {
-        self.anchor_col
-    }
-}
-
-/// Cleanup terminal state when TerminalGuard is dropped.
-///
-/// This implements TUI-08: Terminal restores correctly after normal exit.
-///
-/// # Cleanup Process
-/// 1. Conditionally clear terminal content (based on keep_output flag)
-/// 2. Disable raw mode (restore normal terminal behavior)
-///
-/// # Error Handling
-/// Errors are intentionally ignored during cleanup since:
-/// - We're already exiting and can't meaningfully handle errors
-/// - Best-effort restoration is better than panicking during Drop
-/// - The panic hook provides a second layer of safety for abnormal exits
-impl Drop for TerminalGuard {
-    fn drop(&mut self) {
-        if self.popup_mode {
-            // Popup mode: screen restoration handled by caller before drop.
-            // Raw mode is owned by atuin-hex, don't touch it.
-            return;
-        }
-
-        // Clear terminal content only if keep_output is false - ignore errors (best-effort)
-        if !self.keep_output {
-            let _ = self.terminal.clear();
-        }
-
-        // Disable raw mode to restore normal terminal behavior - ignore errors
-        let _ = disable_raw_mode();
-    }
-}
-
-#[cfg(test)]
-mod tests {
-    use super::*;
-
-    #[test]
-    fn test_panic_hook_installation() {
-        // Test that panic hook can be installed without error
-        install_panic_hook();
-        // Installing again should work (replaces previous hook)
-        install_panic_hook();
-    }
-
-    // Note: Cannot easily test TerminalGuard::new() in CI since it requires a TTY.
-    // Manual testing required for:
-    // 1. Non-TTY detection: echo "" | cargo run -p atuin-ai -- inline
-    // 2. Drop cleanup: Run inline command, press Esc, verify terminal is normal
-    // 3. Panic recovery: Add panic!("test") after TerminalGuard::new(), verify terminal is usable
-}