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Author: phax

CLAUDE.md

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+# CLAUDE.md
+
+This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.
+
+## Project Overview
+
+ph-css is a Java-based CSS 3 parser and builder library (v8.1.2-SNAPSHOT). It parses CSS into a Java object model, supports traversal/modification via the visitor pattern, and can serialize back to CSS. The companion module `ph-csscompress-maven-plugin` provides build-time CSS compression.
+
+## Build Commands
+
+```bash
+# Full build (requires Java 17+, Maven 3.x)
+mvn clean install
+
+# Run all tests
+mvn test
+
+# Run a single test class
+mvn -pl ph-css test -Dtest=CSSReaderFuncTest
+
+# Run a single test method
+mvn -pl ph-css test -Dtest=CSSReaderFuncTest#testReadBadButSucceeding
+
+# Build only the main library
+mvn -pl ph-css clean install
+
+# Build only the Maven plugin
+mvn -pl ph-csscompress-maven-plugin clean install
+
+# Check license headers
+mvn license:check
+```
+
+## Module Structure
+
+- **`ph-css/`** - Core library: CSS parsing, object model, and serialization
+- **`ph-csscompress-maven-plugin/`** - Maven Mojo for CSS compression at build time
+
+## Architecture
+
+### Parser (JavaCC-generated)
+
+Grammar files in `ph-css/src/main/jjtree/`:
+- `ParserCSS30.jjt` - Main CSS 3.0 grammar
+- `ParserCSSCharsetDetector.jjt` - Charset detection
+
+JavaCC generates parser sources into `target/generated-sources/jjtree` and `target/generated-sources/javacc`. Do not edit generated parser files directly; modify the `.jjt` grammars instead.
+
+### Core Package Layout (`com.helger.css`)
+
+| Package | Purpose |
+|---------|---------|
+| `decl` | CSS object model: `CascadingStyleSheet`, style/media/font-face/keyframes rules, declarations |
+| `decl.visit` | Visitor pattern interfaces and implementations for CSS traversal |
+| `decl.shorthand` | Shorthand CSS property expansion |
+| `reader` | `CSSReader` (full stylesheets), `CSSReaderDeclarationList` (inline styles) |
+| `reader.errorhandler` | Parse error handlers (logging, collecting, throwing) |
+| `writer` | `CSSWriter` for serializing the object model back to CSS text |
+| `parser` | JavaCC-generated parser classes (do not edit manually) |
+| `property` | CSS property definitions and metadata (`ECSSProperty`, `CCSSProperties`) |
+| `propertyvalue` | Typed CSS values (colors, functions, URIs, etc.) |
+| `media` | Media query model and `ECSSMedium` enum |
+| `tools` | Utilities like `MediaQueryTools` |
+| `utils` | Helpers for colors, numbers, URLs, rectangles |
+| `annotation` | Custom annotations (`@DeprecatedInCSS`) |
+| `handler` | Exception handlers for the parser |
+
+### Read/Write Flow
+
+1. **Reading**: `CSSReader.readFromString/File/Stream()` -> JavaCC parser -> `CascadingStyleSheet` object model
+2. **Manipulation**: Visitor pattern via `ICSSVisitor` / `DefaultCSSVisitor` on the object model
+3. **Writing**: `CSSWriter.getCSSAsString(CascadingStyleSheet)` -> CSS text output, controlled by `CSSWriterSettings` (minified/formatted, version)
+
+### Key Dependencies
+
+- `ph-commons` (12.1.5) - Collection types (`ICommonsList`, `CommonsArrayList`), I/O utilities, type conversion
+- `ph-javacc-maven-plugin` (5.0.1) - Parser generation from `.jjt` grammars
+- JUnit 4 for tests
+
+## Test Resources
+
+CSS test files live in `ph-css/src/test/resources/testfiles/css30/`:
+- `good/` - Valid CSS files (used to verify successful parsing)
+- `bad/` - Invalid CSS files (expected to fail parsing)
+- `bad_but_succeeding/` - Invalid CSS that the parser recovers from
+- `bad_but_browsercompliant/` - Invalid CSS that browsers accept
+
+## Coding Conventions
+
+See the global rules in `~/.claude/rules/naming.md` for Hungarian notation, formatting, and naming. Key project-specific points:
+- OSGi bundle packaging (`<packaging>bundle</packaging>`) via `maven-bundle-plugin`
+- Apache 2.0 license header required on all Java files (enforced by `license-maven-plugin`)
+- Forbidden APIs plugin blocks unsafe/deprecated JDK usage