Feature Request: Enhance M4B metadata tagging using Audible Catalog API fields

[N0cky]

ReadMeABook already organizes downloaded audiobooks and writes basic audio metadata during import. It would be great to expand the metadata tagging step so organized M4B/M4A/MP3/FLAC files receive richer Audible-style tags, similar to the Mp3tag “Audible via API” web source script.

Reference:
https://community.mp3tag.de/t/ws-audible-via-api/64347

That Mp3tag source uses Audible’s catalog API and maps a broad set of audiobook metadata fields into audio tags. ReadMeABook already uses Audible/Audnexus metadata for search, requests, and organization, so this feels like a natural extension of the current import pipeline.

Current Behavior

During file organization, ReadMeABook writes basic metadata such as:

• title / album
• author / album artist / artist
• narrator / composer
• year
• Audible ASIN
• series / series part

Cover art is copied as cover.jpg, but not embedded into the M4B file.

Desired Behavior

Add an optional “enhanced metadata tagging” mode that writes more Audible metadata into organized audio files, especially M4B files.

Suggested fields:

• ALBUM / title: book title
• SUBTITLE: Audible subtitle
• ALBUMARTIST: author
• ALBUMARTISTS: full author list when multiple authors exist
• ARTIST: author, optionally narrator
• COMPOSER: narrator
• ASIN: Audible ASIN
• DESCRIPTION: publisher summary for M4B
• COMMENT: publisher summary for MP3
• GENRE: Audible category ladder / genres
• PUBLISHER: publisher name
• YEAR: release year or full release date depending on setting
• RELEASETIME: full Audible release date
• LANGUAGE: language
• FORMAT: format type, e.g. unabridged
• ISBN: ISBN when available
• COPYRIGHT: copyright when available
• RATING: Audible rating
• ITUNESMEDIATYPE: Audiobook
• ITUNESGAPLESS: 1
• ITUNESADVISORY: explicit/clean when available
• SERIES: series name
• SERIES-PART: series position
• CONTENTGROUP: “Series, Book #”
• MOVEMENTNAME: series name
• MOVEMENT: series part
• SHOWMOVEMENT: 1 when series metadata exists
• ALBUMSORT: useful sortable value, e.g. Series 1 - Title or Title - Subtitle
• WWWAUDIOFILE: locale-specific Audible product URL

Optional Settings

It would be useful if this followed the same style of options as the Mp3tag source:

• Add narrator to ARTIST
• Use only the first author in ALBUMARTIST, store all authors in ALBUMARTISTS
• Use only the first genre, optionally store additional genres separately
• Use full release date as YEAR instead of just the year
• Configurable delimiter for multiple genres/authors

These could live near the existing metadata tagging setting in the Paths/Admin settings area.

Metadata Source

The Mp3tag source uses Audible’s catalog API with response groups like:

category_ladders,contributors,media,product_desc,product_attrs,product_extended_attrs,rating,series,product_details