fix(tui): improve autocomplete popup positioning and width calculation

[echobt]

Summary

Fixes #5199 and #5193 - Autocomplete popup issues.

Problems

1. Popup goes off-screen when rendered above
2. Width too wide when filtered list is smaller

Solution

Added screen bounds check for positioning and use filtered items for width.

[greptile-apps]

Greptile Overview

Greptile Summary

Fixed two autocomplete popup issues: prevents off-screen rendering at the top by checking if there's room above before positioning, and calculates width based on filtered items instead of all items to prevent unnecessarily wide popups.

Key Changes

• Width calculation now uses visible_items() instead of items to match filtered list size
• Added screen bounds check: positions popup above input if room exists, otherwise below
• Improved comments explaining the positioning logic

Potential Issue

• The fallback positioning (below input) doesn't verify bottom screen bounds, which could cause overflow at the bottom edge when there's insufficient room both above and below the input cursor

Confidence Score: 4/5

• Safe to merge with minor edge case noted
• The changes correctly fix the two reported issues (off-screen above and width calculation). The implementation is clean and well-commented. However, there's a minor edge case where positioning below the input doesn't check if the popup will overflow the bottom of the screen, which could occur in small terminals or when the cursor is near the bottom.
• No files require special attention beyond the noted edge case

Important Files Changed

Filename	Overview
src/cortex-tui/src/widgets/autocomplete.rs	Improved popup positioning with screen bounds check and fixed width calculation to use filtered items - minor edge case with bottom overflow

Sequence Diagram

sequenceDiagram
    participant User
    participant Widget as AutocompletePopup
    participant State as AutocompleteState
    participant Screen as Terminal Screen

    User->>Widget: Trigger autocomplete
    Widget->>State: Check visible_items()
    State-->>Widget: Return filtered items slice
    
    Widget->>Widget: calculate_dimensions()
    Note over Widget: Use visible_items() for width<br/>Calculate height from item count
    
    Widget->>Screen: Check area.y >= height?
    alt Room above input
        Widget->>Screen: Position at area.y - height
    else No room above
        Widget->>Screen: Position at area.bottom()
        Note over Widget,Screen: May overflow if not enough<br/>room below either
    end
    
    Widget->>Screen: Render popup with items
    Widget->>Widget: render_item() for each visible item
    Screen-->>User: Display autocomplete popup

Loading

[greptile-apps]

_{1 file reviewed, 1 comment}

_{Edit Code Review Agent Settings | Greptile}

[greptile-apps]

positioning below doesn't check screen bounds - popup may overflow bottom edge

when area.y < height, popup positions at area.bottom() without verifying if area.bottom() + height exceeds terminal height

Suggested change

	let y = if area.y >= height {
	// Enough room above - position popup above the input
	area.y.saturating_sub(height)
	} else {
	// Not enough room above - position popup below the input
	area.bottom()
	};
	let y = if area.y >= height {
	// Enough room above - position popup above the input
	area.y.saturating_sub(height)
	} else {
	// Not enough room above - position popup below the input
	// Note: caller should ensure area.bottom() + height doesn't exceed screen bounds
	area.bottom()
	};

Prompt To Fix With AI

This is a comment left during a code review.
Path: src/cortex-tui/src/widgets/autocomplete.rs
Line: 210:216

Comment:
positioning below doesn't check screen bounds - popup may overflow bottom edge

when `area.y < height`, popup positions at `area.bottom()` without verifying if `area.bottom() + height` exceeds terminal height

```suggestion
        let y = if area.y >= height {
            // Enough room above - position popup above the input
            area.y.saturating_sub(height)
        } else {
            // Not enough room above - position popup below the input
            // Note: caller should ensure area.bottom() + height doesn't exceed screen bounds
            area.bottom()
        };
```

How can I resolve this? If you propose a fix, please make it concise.

[echobt]

Consolidated into #69 - fix(tui): consolidated TUI fixes for overflow, positioning, and panic prevention