feat: add PR summaries, interactive commands, changelog generation, and path-based config

- Add comprehensive PR summary generation with statistics and risk analysis
- Implement interactive @diffscope commands for PR comments
- Create changelog/release notes generator with conventional commit support
- Add path-based configuration for customizing review behavior
- Support for focus areas, severity overrides, and custom prompts per path
- Generate changelogs grouped by change type with emoji support
- Full documentation and examples for all new features

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

Author: haasonsaas

.diffscope.yml.example

@@ -0,0 +1,88 @@
+# DiffScope Configuration Example
+# Rename this file to .diffscope.yml to use
+
+# Model configuration
+model: gpt-4o
+temperature: 0.2
+max_tokens: 4000
+
+# API configuration (optional - can use environment variables)
+# api_key: your-api-key-here
+# base_url: https://api.openai.com/v1
+
+# Global exclude patterns
+exclude_patterns:
+  - "**/*.generated.*"
+  - "**/node_modules/**"
+  - "**/target/**"
+  - "**/.git/**"
+  - "**/dist/**"
+  - "**/build/**"
+
+# Path-specific configurations
+paths:
+  # API endpoints need extra security focus
+  "src/api/**":
+    focus:
+      - security
+      - validation
+      - authentication
+    severity_overrides:
+      security: error  # Elevate all security issues to errors
+    system_prompt: |
+      Pay special attention to:
+      - SQL injection vulnerabilities
+      - Authentication bypass risks
+      - Input validation gaps
+      - Rate limiting implementation
+
+  # Test files have different requirements
+  "tests/**":
+    focus:
+      - coverage
+      - assertions
+      - test_quality
+    severity_overrides:
+      style: suggestion  # Downgrade style issues in tests
+    ignore_patterns:
+      - "*.snapshot"
+      - "*.fixture"
+
+  # Frontend components
+  "src/components/**":
+    focus:
+      - accessibility
+      - performance
+      - react_best_practices
+    extra_context:
+      - "src/styles/theme.ts"  # Always include theme context
+
+  # Database migrations are critical
+  "migrations/**":
+    focus:
+      - data_integrity
+      - rollback_safety
+      - performance
+    severity_overrides:
+      bug: error  # All bugs in migrations are critical
+    system_prompt: |
+      Database migrations are critical. Check for:
+      - Data loss risks
+      - Rollback capability
+      - Index performance impact
+      - Lock duration concerns
+
+  # Documentation files
+  "docs/**":
+    focus:
+      - clarity
+      - completeness
+      - examples
+    severity_overrides:
+      bug: info  # Bugs in docs are less critical
+
+# Plugin configuration
+plugins:
+  eslint: true
+  semgrep: true
+  duplicate_filter: true

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "diffscope"
-version = "0.4.4"
+version = "0.5.0"
 edition = "2021"
 authors = ["Jonathan Haas <jonathan@haas.holdings>"]
 description = "A composable code review engine with smart analysis, confidence scoring, and professional reporting"
@@ -26,6 +26,8 @@ git2 = "0.18"
 once_cell = "1.19"
 regex = "1.10"
 dirs = "5.0"
+chrono = "0.4"
+glob = "0.3"
 
 [dev-dependencies]
 tempfile = "3.8"

README.md

@@ -6,14 +6,17 @@ A composable code review engine for automated diff analysis.
 
 - **Model Agnostic**: Works with OpenAI, Anthropic Claude 4, Ollama, and any OpenAI-compatible API
 - **Git Integration**: Review uncommitted, staged, or branch changes directly
-- **PR Reviews**: Analyze and comment on GitHub pull requests
+- **PR Reviews**: Analyze and comment on GitHub pull requests with interactive commands
 - **Smart Prompting**: Advanced prompt engineering with examples, XML structure, and chain-of-thought
 - **Commit Messages**: AI-powered commit message suggestions following conventional commits
 - **Composable Architecture**: Modular components that work together
 - **Plugin System**: Extensible pre-analyzers and post-processors
 - **Multiple Outputs**: JSON, patch, or markdown formats
 - **CI/CD Ready**: GitHub Action, GitLab CI, and Docker support
 - **Smart Review**: Enhanced analysis with confidence scoring, fix effort estimation, and executive summaries
+- **Path-Based Configuration**: Customize review behavior for different parts of your codebase
+- **Changelog Generation**: Generate changelogs and release notes from git history
+- **Interactive Commands**: Respond to PR comments with @diffscope commands
 
 ## Quick Start
 
@@ -430,6 +433,104 @@ stage('AI Code Review') {
 5. **Output Parsing**: Handle both empty reviews and JSON parsing errors gracefully
 6. **Conditional Runs**: Skip reviews on draft PRs or specific file types
 
+## New Features in v0.5.0
+
+### 🔄 Changelog Generation
+
+Generate professional changelogs and release notes from your git history:
+
+```bash
+# Generate changelog from a specific tag to HEAD
+diffscope changelog --from v0.4.0 --to HEAD
+
+# Generate release notes for a new version
+diffscope changelog --release v0.5.0 --from v0.4.0
+
+# Output to file
+diffscope changelog --from v0.4.0 --output CHANGELOG.md
+```
+
+The changelog generator:
+- Parses conventional commits automatically
+- Groups changes by type (features, fixes, etc.)
+- Highlights breaking changes
+- Shows contributor statistics
+- Generates both changelogs and release notes formats
+
+### 🎯 Path-Based Configuration
+
+Customize review behavior for different parts of your codebase:
+
+**.diffscope.yml**
+```yaml
+# Global configuration
+model: gpt-4o
+temperature: 0.2
+max_tokens: 4000
+
+# Exclude patterns
+exclude_patterns:
+  - "**/*.generated.*"
+  - "**/node_modules/**"
+
+# Path-specific rules
+paths:
+  # API endpoints need security focus
+  "src/api/**":
+    focus:
+      - security
+      - validation
+      - authentication
+    severity_overrides:
+      security: error  # All security issues become errors
+    system_prompt: |
+      Focus on SQL injection, auth bypass, and input validation
+
+  # Test files have different standards
+  "tests/**":
+    focus:
+      - coverage
+      - assertions
+    severity_overrides:
+      style: suggestion  # Style issues are just suggestions
+
+  # Database migrations are critical
+  "migrations/**":
+    severity_overrides:
+      bug: error  # Any bug in migrations is critical
+```
+
+### 💬 Interactive PR Commands
+
+Respond to pull request comments with interactive commands:
+
+```
+@diffscope review                 # Re-review the changes
+@diffscope review security        # Focus review on security
+@diffscope ignore src/generated/  # Ignore specific paths
+@diffscope explain line 42        # Explain specific code
+@diffscope generate tests         # Generate unit tests
+@diffscope help                   # Show all commands
+```
+
+### 📊 PR Summary Generation
+
+Generate executive summaries for pull requests:
+
+```bash
+# Generate PR summary with statistics
+diffscope pr --summary
+
+# Generate and post to GitHub
+diffscope pr --number 123 --summary --post-comments
+```
+
+The summary includes:
+- Change statistics and impact analysis
+- Key modifications by category
+- Risk assessment
+- Review recommendations
+
 ## Contributing
 
 Contributions are welcome! Please open an issue first to discuss what you would like to change.

RELEASE_NOTES.md

@@ -0,0 +1,70 @@
+# Release Notes - v0.5.0
+
+📅 **Release Date**: 2025-06-06
+
+## 📊 Summary
+
+This release brings major new features inspired by CodeRabbit, including PR summary generation, interactive commands, changelog generation, and path-based configuration.
+
+- 🎯 **Total Changes**: 4 major features
+- ✨ **New Features**: 4
+- 🐛 **Bug Fixes**: 0
+- ⚠️ **Breaking Changes**: 0
+
+## ✨ Highlights
+
+### 1. PR Summary Generation
+- Generate comprehensive executive summaries for pull requests
+- Includes statistics, change analysis, and risk assessment
+- Seamless GitHub integration with `diffscope pr --summary`
+
+### 2. Interactive PR Commands
+- Respond to PR comments with `@diffscope` commands
+- Support for review, ignore, explain, generate, and help commands
+- Makes code review more collaborative and interactive
+
+### 3. Changelog & Release Notes Generation
+- Automatically parse conventional commits
+- Generate professional changelogs with `diffscope changelog`
+- Support for both changelog and release notes formats
+- Group changes by type with emoji support
+
+### 4. Path-Based Configuration
+- Configure review behavior per directory/file pattern
+- Set custom focus areas, severity overrides, and prompts
+- Support for exclude patterns and path-specific rules
+- Example: Elevate all security issues to errors in API endpoints
+
+## 🔧 Configuration
+
+Create a `.diffscope.yml` file to customize behavior:
+
+```yaml
+# Path-specific rules
+paths:
+  "src/api/**":
+    focus: [security, validation]
+    severity_overrides:
+      security: error
+```
+
+## 🚀 Getting Started
+
+```bash
+# Install the latest version
+cargo install diffscope
+
+# Generate a changelog
+diffscope changelog --from v0.4.0
+
+# Use path-based configuration
+cp .diffscope.yml.example .diffscope.yml
+```
+
+## 👥 Contributors
+
+- Jonathan Haas (@Haasonsaas)
+
+## 📝 Full Changelog
+
+For detailed changes, see the [full changelog](https://github.com/Haasonsaas/diffscope/compare/v0.4.4...v0.5.0).