#!/bin/sh

# Commit message validation
# Enforces conventional commit format: type(scope)!?: description
#
# Valid types: feat, fix, docs, style, refactor, perf, test, build, ci, chore, revert
# Scope allows: letters, numbers, hyphens, underscores, slashes, dots
# Optional ! for breaking changes
# Examples:
#   feat(tasks): add drag and drop support
#   fix(terminal): resolve scroll position issue
#   feat!: breaking change without scope
#   feat(api)!: breaking change with scope
#   docs: update README with setup instructions
#   chore: update dependencies

commit_msg_file=$1
commit_msg=$(cat "$commit_msg_file")

# Regex for conventional commits
# Format: type(optional-scope)!?: description
# Scope allows: letters, numbers, hyphens, underscores, slashes, dots (consistent with GitHub workflow)
# Optional ! for breaking changes: feat!: or feat(scope)!:
pattern="^(feat|fix|docs|style|refactor|perf|test|build|ci|chore|revert)(\([a-zA-Z0-9_/.-]+\))?!?: .{1,100}$"

# Allow merge commits
if echo "$commit_msg" | grep -qE "^Merge "; then
  exit 0
fi

# Allow revert commits
if echo "$commit_msg" | grep -qE "^Revert "; then
  exit 0
fi

# Check first line against pattern
first_line=$(echo "$commit_msg" | head -n 1)

if ! echo "$first_line" | grep -qE "$pattern"; then
  echo ""
  echo "ERROR: Invalid commit message format!"
  echo ""
  echo "Your message: $first_line"
  echo ""
  echo "Expected format: type(scope)!?: description"
  echo ""
  echo "Valid types:"
  echo "  feat     - A new feature"
  echo "  fix      - A bug fix"
  echo "  docs     - Documentation changes"
  echo "  style    - Code style changes (formatting, semicolons, etc.)"
  echo "  refactor - Code refactoring (no feature/fix)"
  echo "  perf     - Performance improvements"
  echo "  test     - Adding or updating tests"
  echo "  build    - Build system or dependencies"
  echo "  ci       - CI/CD configuration"
  echo "  chore    - Other changes (maintenance)"
  echo "  revert   - Reverting a previous commit"
  echo ""
  echo "Examples:"
  echo "  feat(tasks): add drag and drop support"
  echo "  fix(terminal): resolve scroll position issue"
  echo "  feat!: breaking change without scope"
  echo "  feat(api)!: breaking change with scope"
  echo "  docs: update README"
  echo "  chore: update dependencies"
  echo ""
  exit 1
fi

# Check description length (max 100 chars for first line)
if [ ${#first_line} -gt 100 ]; then
  echo ""
  echo "ERROR: Commit message first line is too long!"
  echo "Maximum: 100 characters"
  echo "Current: ${#first_line} characters"
  echo ""
  exit 1
fi

exit 0