# Diff Review Mode

Diff review mode provides read-only navigation for unified and classic diff files with speech-first output.

## Quick Workflow

1. Copy the full absolute path of a diff file to the Fenrir clipboard.
2. Press `Fenrir + Ctrl + D` to toggle diff mode on.
3. Review the diff using the keys below.
4. Press `Esc` to leave diff mode.

If the clipboard does not contain a full absolute file path, Fenrir announces an error and does not enter diff mode.

## Keys (Active Only In Diff Mode)

- `h` - Next hunk
- `Shift + h` - Previous hunk
- `f` - Next file section
- `Shift + f` - Previous file section
- `a` - Next added line
- `Shift + a` - Previous added line
- `d` - Next removed line
- `Shift + d` - Previous removed line
- `Up` - Previous line
- `Down` - Next line
- `Left` - Previous character
- `Right` - Next character
- `Ctrl + Left` - Previous word
- `Ctrl + Right` - Next word
- `s` - Diff summary
- `F1` - Speak key help
- `Esc` - Exit diff mode

## Speech Behavior

- Added and removed content is spoken as `Added:` and `Removed:` lines.
- Marker-only lines are normalized for speech:
  - `+++` is spoken as `added`
  - `---` is spoken as `removed`
- Classic diff markers are spoken in plain language:
  - `17c17` -> `line 17 changed`
  - `17d16` -> `line 17 deleted`
  - `16a17` -> `line 17 added`

## Notes

- Diff mode is read-only and does not modify the diff file.
- Normal Fenrir key bindings are restored when diff mode exits.