# CHANGELOG

All notable changes to **h4b-image-optim** will be documented here.

Format follows [Keep a Changelog](https://keepachangelog.com/en/1.1.0/) and
[Semantic Versioning](https://semver.org/spec/v2.0.0.html).

## [0.2.0] — 2026-05-19

Added migrate-from-smush + Picture-tag rewriter. The plugin is now usable
end-to-end on a site that previously ran Smush — no double-processing, and
WebP / AVIF actually get served to visitors.

### Added
- **`wp h4b-img migrate-from-smush`** — reads Smush's `wp-smpro-smush-data`
  postmeta, writes equivalent `_h4b_img_optim` markers so our bulk command
  skips already-optimised attachments.
  - `--dry-run` to see counts only
  - `--force-rescan` to mark for re-optimisation instead (use when migrating
    off Smush completely)
  - `--remove-smush-meta` to delete the Smush postmeta after migration
- **`Picture_Tag`** rewriter (the_content + post_thumbnail_html + widget_text +
  Elementor frontend + wp_get_attachment_image filters at priority 99). Wraps
  `<img>` tags with `<picture><source type="image/avif"><source type="image/webp"><img></picture>`
  when sibling files exist on disk.
  - Skips images already inside a `<picture>` block (double-wrap protection
    via byte-range tracking)
  - Skips images with `data-no-h4b` attribute (per-image opt-out)
  - Resolves siblings either alongside the JPG (`foo.jpg.webp`) or in Smush's
    `wp-content/smush-webp/` mirror tree
  - Caches sibling lookups per request to keep it cheap
  - Preserves srcset, sizes, alt, class, and all other original `<img>` attrs

### Verified
- migrate-from-smush: 100 attachments migrated cleanly on dev.rds.ink
- bulk count correctly drops after migration (734 → 634)
- Picture_Tag: 8 edge-case tests pass (no siblings, multiple images, opt-out,
  srcset preservation, external URLs, no `<img>`, existing `<picture>`, mixed)

## [0.1.0] — 2026-05-19

Initial MVP. Replaces Smush Pro's optimisation pipeline without the
grey-wash bug. CLI-only in this release (admin UI comes in 0.2).

### Added
- **Plugin scaffold** with PSR-12-style namespaced classes (`H4B\ImageOptim\*`)
- **`Optimizer`** — in-place JPG / PNG re-encode using Imagick + jpegoptim / pngquant
  - **ICC profile preservation** (the Smush-bug fix) via bundled sRGB v4 profile fallback
  - 4:4:4 chroma subsampling for large images; 4:2:0 for small ones
  - Configurable size threshold (`min_optimise_bytes`, default 20 KB) to skip
    thumbnails that re-encoding would inflate
  - Atomic file replacement with ownership preservation
  - GPS EXIF stripping on by default for privacy
  - EXIF orientation applied before encode
- **`Format_Generator`** — WebP (synchronous) + AVIF (queued via WP-Cron) siblings
- **`Uploader_Hook`** — intercepts `wp_generate_attachment_metadata`
- **`Attachment_Meta`** — per-attachment optimisation history in `_h4b_img_optim`
- **`Rescue_Detector`** — PHP port of the Python grey-wash detector
- **Originals backup** to `wp-content/h4b-img-originals/` with 90-day cron prune
- **WP-CLI commands**:
  - `wp h4b-img status` — tool detection + settings dump
  - `wp h4b-img optimise --id=<n>` — single-attachment optimise (+ `--dry-run`)
  - `wp h4b-img bulk` — bulk-optimise unprocessed attachments (+ `--limit`,
    `--force`, `--dry-run`, `--batch`, `--pause`)
  - `wp h4b-img rescue` — scan + optionally repair Smush-mangled JPGs from
    their `.webp` siblings (+ `--scan`, `--apply`, `--min-severity`, `--csv`,
    `--manifest`)
- **`uninstall.php`** — clean removal of plugin options + cron, preserves
  user data (backups + .webp/.avif siblings + optimisation postmeta)

### Required system tools (AlmaLinux 9 / Debian 13)

| Tool | AlmaLinux | Debian |
|---|---|---|
| `cwebp` | `libwebp-tools` | `webp` |
| `jpegoptim` | `jpegoptim` | `jpegoptim` |
| `cjpeg` / `jpegtran` | `libjpeg-turbo-utils` | `libjpeg-turbo-progs` |
| `avifenc` | `libavif-tools` | `libavif-bin` |
| `pngquant` | `pngquant` | `pngquant` |
| `optipng` | `optipng` | `optipng` |

### Known limitations
- No admin settings page (CLI/`wp option` only)
- No Picture-tag rewriting on `the_content` (Smush still serving WebPs)
- No `.htaccess` content-negotiation fallback
- No `migrate-from-smush` command yet
- No PHPUnit test suite yet

### Verified against
- AlmaLinux 9.7 / PHP 8.4.21 / Imagick 3.8.1 (production)
- Debian 13 / PHP 8.4 / wordpress:php8.4-apache (dev container)
- Tested on 20 rds.ink attachments in bulk mode: 487 KB saved (10.4%), 0 errors
- Rescue mechanic verified end-to-end on the WorkingAsOne_horse900-800x524.jpg fixture