Lutaml integration

.gitignore

@@ -12,3 +12,4 @@
 .rspec_status
 Gemfile.lock
 .vscode/
+.claude/

.rubocop.yml

@@ -7,6 +7,6 @@ require: rubocop-rails
 inherit_from:
   - https://raw.githubusercontent.com/riboseinc/oss-guides/master/ci/rubocop.yml
 AllCops:
-  TargetRubyVersion: 3.0
+  TargetRubyVersion: 3.2
 Rails:
   Enabled: false

CLAUDE.md

@@ -0,0 +1,79 @@
+# CLAUDE.md
+
+This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.
+
+## Project Overview
+
+relaton-plateau is a Ruby gem for retrieving and managing bibliographic metadata for Project PLATEAU (Japanese 3D city model standards published by MLIT). It is part of the Relaton ecosystem of bibliographic gems.
+
+## Commands
+
+```bash
+# Install dependencies
+bundle install
+
+# Run all tests
+bundle exec rake spec
+
+# Run a single test file
+bundle exec rspec spec/relaton/plateau/bibitem_spec.rb
+
+# Run a specific test by line number
+bundle exec rspec spec/relaton/plateau/bibitem_spec.rb:15
+
+# Lint
+bundle exec rake rubocop
+
+# Default rake task (runs specs)
+bundle exec rake
+```
+
+## Architecture
+
+All code lives in `lib/relaton/plateau/`. The gem uses LutaML::Model::Serializable for data modeling with automatic XML/YAML serialization.
+
+### Models
+- **Item** (`item.rb`) — base Plateau item extending `Bib::Item`, declares `model ItemData` and adds `ext` attribute
+- **ItemData** (`item_data.rb`) — data class extending `Bib::ItemData`, returned by `Item.from_xml`, `Item.from_yaml`, and `Bibliography.get`
+- **Bibitem** (`bibitem.rb`) — bibliographic item variant (includes `Bib::BibitemShared`)
+- **Bibdata** (`bibdata.rb`) — bibliographic data variant (includes `Bib::BibdataShared`)
+- **Ext** (`ext.rb`) — extension element: doctype, subdoctype, flavor, editorialgroup, stagename, filesize, etc.
+- **Doctype** (`doctype.rb`) — extends `Bib::Doctype`, valid values: `handbook`, `technical-report`, `annex`
+
+### Retrieval & Data Fetching
+- **Bibliography** (`bibliography.rb`) — module with `get(code)` for index-based document retrieval, returns `ItemData`
+- **HitCollection** / **Hit** — search the relaton-data-plateau index and fetch YAML documents
+- **DataFetcher** (`data_fetcher.rb`) — extends `Core::DataFetcher`, scrapes MLIT JSON APIs for handbooks and technical reports
+- **Parser** / **HandbookParser** / **TechnicalReportParser** — parse JSON into `ItemData` objects
+- **Processor** (`processor.rb`) — standard Relaton processor plugin (`get`, `from_xml`, `from_yaml`, `fetch_data`, `grammar_hash`)
+
+### Serialization Methods
+- `bib.to_xml` — XML (bibitem format)
+- `Item.to_yaml(bib)` — YAML (class method)
+- `bib.to_rfcxml` — BibXML/RFC XML
+- `Item.from_xml(xml)` — parse XML into `ItemData`
+- `Item.from_yaml(yaml)` — parse YAML into `ItemData`
+
+### Data Sources
+- Handbooks: `https://www.mlit.go.jp/plateau/_next/data/1.3.0/libraries/handbooks.json`
+- Technical Reports: `https://www.mlit.go.jp/plateau/_next/data/1.3.0/libraries/technical-reports.json`
+- Pre-fetched index: `https://raw.githubusercontent.com/relaton/relaton-data-plateau/data-v2/`
+
+### Schema Validation
+RNG grammar files in `grammars/` define the XML schema. Tests validate fixtures against `relaton-plateau-compile.rng` using the `ruby-jing` gem.
+
+## Testing
+
+- **Index fixture:** `spec/fixtures/index-v1.zip` is pre-loaded into `Relaton::Index` pool in `before(:suite)` (configured in `spec/support/webmock.rb`). Run `rake spec:update_index` to refresh from relaton-data-plateau.
+- RSpec with `expect` syntax (no monkey-patching)
+- VCR cassettes record HTTP interactions (in `spec/fixtures/vcr_cassettes/`)
+- `equivalent-xml` for XML comparison assertions
+- `jing` matcher for RNG schema validation
+- SimpleCov for code coverage
+
+## Key Conventions
+
+- Document identifiers follow pattern: `PLATEAU Handbook #XX Y.Z` or `PLATEAU Technical Report #XX Y.Z`
+- The gem supports multi-format serialization: XML, YAML, BibXML (RFC XML)
+- RuboCop follows Ribose OSS style guide; target Ruby version is 3.0
+- The `ext` element in XML/YAML carries PLATEAU-specific metadata (doctype, flavor, editorialgroup, etc.)

Gemfile

@@ -9,6 +9,7 @@ gem "equivalent-xml", "~> 0.6"
 gem "rake", "~> 13.0"
 gem "rspec", "~> 3.0"
 gem "rubocop", "~> 1.21"
+gem "ruby-jing", "~> 0.0.3"
 gem "simplecov", "~> 0.22"
 gem "vcr", "~> 6.0"
 gem "webmock", "~> 3.0"