File truncation/rotation during mmap lifetime caused SIGBUS crash
because update_for_append() ignored new_size < old_size, leaving
a stale mapping that would fault on access.
Introduce AppendStatus enum (Unchanged/Appended/Reloaded) so the
caller can distinguish shrink events from normal appends. On shrink,
reload() rebuilds the mmap and line index. The TUI layer clamps
cursor and invalidates viewport cache on Reloaded, matching the
existing handle_file_truncated() behavior.
Fixes#1
During Loading state (before VHI is built), j/k used to jump by logical
line, visually skipping multiple wrapped rows. Now uses v_sub_offset to
track position within a wrapped line, enabling smooth 1-visual-row scroll.
- Add v_sub_offset field to App for sub-line visual position tracking
- scroll_down/up_line else branch: advance v_sub_offset, wrap to next line
- ensure_viewport_cache Loading path: pass v_sub_offset as offset_in_line
- ensure_cursor_visible: skip during Loading (scroll functions manage it)
- Reset v_sub_offset on Loading→Ready, scroll_to_top, scroll_to_bottom
- Add 3 tests for Loading-state sub-offset scrolling behavior
When a JSON line wraps to many visual rows (e.g. 73 rows), pressing j
would skip the entire logical line, making wrapped content unreadable.
Now j/k scroll by 1 visual row when a VisualHeightIndex is available,
with cursor tracking the viewport center. Falls back to logical-line
scroll in Loading/no-index modes or when all content fits the viewport.
Adds 4 tests: visual scroll down, visual scroll up, small-file fallback,
j/k roundtrip.
total_lines() was returning sampled_line_count() (only ~300 lines from the initial 64KB scan) during the Loading state, capping the scroll range. Use estimated_lines instead so the user can scroll to any position while indexing runs in the background. get_line() already supports incremental forward scanning on demand.
Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)
Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>
Replace synchronous file loading with AppLoadingState state machine (Empty/Loading/Ready/Error) for instant interactivity. Add ViewportCache for on-demand viewport computation, replacing global wrap/level caches. Integrate background indexer polling and file watcher events into the TUI event loop. Add loading UI with progress percentage, estimated line numbers with ~ prefix, and error state display. Eliminate all O(N) linear scans using VisualHeightIndex binary search.
Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)
Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>
Replace Line::styled with Span-based rendering: gutter (DarkGray fg) + content (level-based fg color). Add centered settings popup (S key) with j/k navigation, arrow key color cycling, number key shortcuts, Enter to save, Esc to cancel.
Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)
Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>
Add AppMode enum (Normal/Settings), level_cache field populated in recompute_wrap_cache via detect_level(), color_config loaded from TOML in main.rs. Refactor handle_key for mode dispatch with S key to enter settings.
Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)
Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>
Press Tab to switch JSON log lines between raw single-line and indented
multi-line format (2-space indent, like jq output). Only JSON Object lines
are affected; plain text lines stay unchanged.
- Add json_format bool field to App, toggled by Tab
- Add format_json_line() standalone function with serde_json::to_string_pretty
- Integrate into recompute_wrap_cache with \n-split sub-line wrapping
- Center viewport on cursor after cache rebuild to prevent jump on toggle
- Add 12 unit tests covering format, toggle, and edge cases
Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)
Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>
