#!/bin/bash
# Generate release notes from commits since the last tag

set -e

CURRENT_TAG="${1:-${DRONE_TAG}}"
OUTPUT_FILE="${2:-.build/release-notes.md}"

if [ -z "$CURRENT_TAG" ]; then
    echo "Error: Current tag not provided"
    exit 1
fi

# Find the previous tag
PREVIOUS_TAG=$(git describe --tags --abbrev=0 "$CURRENT_TAG"^ 2>/dev/null || echo "")

mkdir -p "$(dirname "$OUTPUT_FILE")"

# Start release notes
{
    echo "# Release $CURRENT_TAG"
    echo ""
    
    if [ -n "$PREVIOUS_TAG" ]; then
        echo "**Changes since $PREVIOUS_TAG:**"
        echo ""
        
        # Extract commits and group by type (feat, fix, docs, ci, etc.)
        git log "$PREVIOUS_TAG..$CURRENT_TAG" --pretty=format:"%s" | while read -r commit; do
            # Parse conventional commits
            if [[ $commit =~ ^([a-z]+)(\(.+\))?:\ (.+)$ ]]; then
                TYPE="${BASH_REMATCH[1]}"
                SCOPE="${BASH_REMATCH[2]}"
                MESSAGE="${BASH_REMATCH[3]}"
                
                case "$TYPE" in
                    feat)
                        echo "- ✨ **Feature**${SCOPE}: $MESSAGE" ;;
                    fix)
                        echo "- 🐛 **Fix**${SCOPE}: $MESSAGE" ;;
                    docs)
                        echo "- 📖 **Docs**${SCOPE}: $MESSAGE" ;;
                    ci)
                        echo "- 🔧 **CI**${SCOPE}: $MESSAGE" ;;
                    test)
                        echo "- ✅ **Test**${SCOPE}: $MESSAGE" ;;
                    refactor)
                        echo "- ♻️ **Refactor**${SCOPE}: $MESSAGE" ;;
                    perf)
                        echo "- ⚡ **Performance**${SCOPE}: $MESSAGE" ;;
                    *)
                        echo "- 📝 $commit" ;;
                esac
            else
                echo "- 📝 $commit"
            fi
        done
    else
        echo "Initial release"
        echo ""
        git log "$CURRENT_TAG" --pretty=format:"- 📝 %s" | head -20
    fi
    
    echo ""
    echo "---"
    echo "See [all changes](https://scm.yoorie.de/git/go-lib/util/compare/$PREVIOUS_TAG...$CURRENT_TAG)"
    
} > "$OUTPUT_FILE"

echo "Release notes generated: $OUTPUT_FILE"
cat "$OUTPUT_FILE"