#!/bin/bash
#
# Commit message hook for MEV Bot V2
# Validates commit message format
#
# Install: ln -sf ../../.git-hooks/commit-msg .git/hooks/commit-msg
#

# Colors
RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[1;33m'
NC='\033[0m' # No Color

COMMIT_MSG_FILE=$1
COMMIT_MSG=$(cat "$COMMIT_MSG_FILE")

# Skip if this is a merge commit
if git rev-parse -q --verify MERGE_HEAD > /dev/null; then
    echo -e "${GREEN}ℹ️  Merge commit detected, skipping validation${NC}"
    exit 0
fi

# Skip if this is an amend
if [ -n "$GIT_EDITOR" ]; then
    echo -e "${GREEN}ℹ️  Amend detected, skipping validation${NC}"
    exit 0
fi

echo -e "${GREEN}📝 Validating commit message...${NC}"

# Required format: type(scope): description
# type: feat, fix, perf, refactor, test, docs, build, ci
# scope: component name (parsers, cache, validation, etc.)

PATTERN="^(feat|fix|perf|refactor|test|docs|build|ci)\([a-z0-9-]+\): .{10,}"

if ! echo "$COMMIT_MSG" | grep -qE "$PATTERN"; then
    echo -e "${RED}❌ Invalid commit message format${NC}"
    echo ""
    echo -e "${YELLOW}Required format:${NC}"
    echo -e "  type(scope): brief description"
    echo ""
    echo -e "${YELLOW}Valid types:${NC}"
    echo -e "  feat     - New feature"
    echo -e "  fix      - Bug fix"
    echo -e "  perf     - Performance improvement"
    echo -e "  refactor - Code refactoring"
    echo -e "  test     - Adding or updating tests"
    echo -e "  docs     - Documentation updates"
    echo -e "  build    - Build system changes"
    echo -e "  ci       - CI/CD changes"
    echo ""
    echo -e "${YELLOW}Example:${NC}"
    echo -e "  feat(parsers): add UniswapV2 parser with event validation"
    echo ""
    echo -e "${YELLOW}Your message:${NC}"
    echo -e "  $COMMIT_MSG"
    echo ""
    exit 1
fi

# Check for minimum description length
DESCRIPTION=$(echo "$COMMIT_MSG" | head -n1 | sed 's/^[^:]*: //')
if [ ${#DESCRIPTION} -lt 10 ]; then
    echo -e "${RED}❌ Commit description too short (minimum 10 characters)${NC}"
    echo -e "${YELLOW}Your description: $DESCRIPTION (${#DESCRIPTION} chars)${NC}"
    exit 1
fi

# Check for maximum line length (72 chars for first line)
FIRST_LINE=$(echo "$COMMIT_MSG" | head -n1)
if [ ${#FIRST_LINE} -gt 72 ]; then
    echo -e "${YELLOW}⚠️  Warning: First line exceeds 72 characters (${#FIRST_LINE} chars)${NC}"
    echo -e "${YELLOW}   Consider shortening the description${NC}"
    echo ""
fi

# Encourage including coverage info for test changes
if echo "$COMMIT_MSG" | grep -q "^test"; then
    if ! echo "$COMMIT_MSG" | grep -qi "coverage"; then
        echo -e "${YELLOW}💡 Tip: Consider including coverage info in test commits${NC}"
        echo ""
    fi
fi

echo -e "${GREEN}✅ Commit message format valid${NC}"
echo ""

exit 0