#!/usr/bin/env bash
# Git Hooks Setup for MEV Bot CI/CD Integration
# Creates git hooks that integrate with the CI/CD pipeline

set -euo pipefail

SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
PROJECT_ROOT="$(cd "$SCRIPT_DIR/.." && pwd)"
HOOKS_DIR="$PROJECT_ROOT/.git/hooks"

cd "$PROJECT_ROOT"

log() {
    echo "[HOOKS-SETUP] $*"
}

error() {
    echo "[ERROR] $*" >&2
}

# Check if we're in a git repository
if ! git rev-parse --git-dir >/dev/null 2>&1; then
    error "Not in a git repository"
    exit 1
fi

log "Setting up Git hooks integration with CI/CD pipeline..."

# Create hooks directory if it doesn't exist
mkdir -p "$HOOKS_DIR"

# Pre-commit hook
cat > "$HOOKS_DIR/pre-commit" << 'EOF'
#!/usr/bin/env bash
# Pre-commit hook - Fast validation before commit

set -e

echo "🔍 Running pre-commit validation..."

# Check if we have staged files
if git diff --cached --quiet; then
    echo "No staged changes to validate"
    exit 0
fi

# Run fast CI validation
if command -v make >/dev/null 2>&1; then
    echo "Running pre-commit CI pipeline..."
    make ci-precommit
else
    echo "Running basic checks..."

    # Basic Go checks
    if command -v go >/dev/null 2>&1; then
        echo "Building..."
        go build ./cmd/mev-bot

        echo "Running tests..."
        go test ./pkg/... -short

        echo "Checking format..."
        if ! gofmt -l . | grep -q .; then
            echo "✅ Code formatting is clean"
        else
            echo "❌ Code needs formatting:"
            gofmt -l .
            echo "Run: gofmt -w ."
            exit 1
        fi

        echo "Running vet..."
        go vet ./...
    fi
fi

echo "✅ Pre-commit validation passed"
EOF

# Pre-push hook
cat > "$HOOKS_DIR/pre-push" << 'EOF'
#!/usr/bin/env bash
# Pre-push hook - Comprehensive validation before push

set -e

echo "🚀 Running pre-push validation..."

# Get the branch being pushed
branch=$(git rev-parse --abbrev-ref HEAD)
echo "Validating branch: $branch"

# Run appropriate CI based on branch type
if command -v make >/dev/null 2>&1; then
    if [[ "$branch" =~ ^(feature|fix)/ ]]; then
        echo "Running development CI for feature/fix branch..."
        make ci-dev
    elif [[ "$branch" =~ ^release/ ]] || [[ "$branch" == "master" ]] || [[ "$branch" == "main" ]]; then
        echo "Running full CI for release/main branch..."
        make ci-full
    else
        echo "Running quick CI for other branches..."
        make ci-quick
    fi
else
    echo "Running basic validation..."

    if command -v go >/dev/null 2>&1; then
        echo "Building..."
        go build ./cmd/mev-bot

        echo "Running full test suite..."
        go test ./...

        echo "Running static analysis..."
        go vet ./...
    fi
fi

echo "✅ Pre-push validation passed"
EOF

# Post-commit hook
cat > "$HOOKS_DIR/post-commit" << 'EOF'
#!/usr/bin/env bash
# Post-commit hook - Optional post-commit actions

# Get commit info
commit_hash=$(git rev-parse HEAD)
commit_msg=$(git log -1 --pretty=%B)
branch=$(git rev-parse --abbrev-ref HEAD)

echo "📝 Post-commit: $commit_hash on $branch"

# Optional: Run quick smoke test after commit
if [[ "$commit_msg" =~ ^(feat|fix|perf): ]]; then
    echo "Running smoke test for significant changes..."
    if command -v make >/dev/null 2>&1; then
        timeout 30 make ci-precommit || echo "Smoke test completed"
    fi
fi
EOF

# Prepare-commit-msg hook
cat > "$HOOKS_DIR/prepare-commit-msg" << 'EOF'
#!/usr/bin/env bash
# Prepare commit message hook - Add conventional commit format help

commit_file="$1"
commit_source="$2"

# Only add template for regular commits (not merges, amendments, etc.)
if [[ "$commit_source" == "" ]] || [[ "$commit_source" == "template" ]]; then
    # Get the branch name
    branch=$(git rev-parse --abbrev-ref HEAD 2>/dev/null || echo "main")

    # Add conventional commit template if message is empty
    if [[ ! -s "$commit_file" ]]; then
        cat >> "$commit_file" << 'TEMPLATE'

# Conventional Commits Format:
# type(scope): description
#
# Types: feat, fix, docs, style, refactor, perf, test, chore
# Example: feat(parser): add support for multicall transactions
#
# Body (optional):
# - Explain what and why vs. how
# - Include motivation for the change
# - Contrast with previous behavior
#
# Footer (optional):
# - Breaking changes: BREAKING CHANGE: <description>
# - Issues: Closes #123, Fixes #456

TEMPLATE
    fi
fi
EOF

# Post-merge hook
cat > "$HOOKS_DIR/post-merge" << 'EOF'
#!/usr/bin/env bash
# Post-merge hook - Actions after merge

echo "🔀 Post-merge validation..."

# Run CI after merge to ensure integration is clean
if command -v make >/dev/null 2>&1; then
    echo "Running post-merge CI validation..."
    make ci-dev
else
    echo "Running basic post-merge checks..."
    if command -v go >/dev/null 2>&1; then
        go build ./cmd/mev-bot
        go test ./pkg/... -short
    fi
fi

# Check if dependencies changed
if git diff HEAD@{1} --name-only | grep -q "go.mod\|go.sum"; then
    echo "📦 Dependencies changed, updating..."
    go mod tidy
    go mod verify
fi

echo "✅ Post-merge validation completed"
EOF

# Pre-rebase hook
cat > "$HOOKS_DIR/pre-rebase" << 'EOF'
#!/usr/bin/env bash
# Pre-rebase hook - Validation before rebase

upstream="$1"
branch="$2"

echo "🔄 Pre-rebase validation..."
echo "Rebasing: ${branch:-$(git rev-parse --abbrev-ref HEAD)} onto $upstream"

# Warn about rebasing public branches
current_branch=${branch:-$(git rev-parse --abbrev-ref HEAD)}
if [[ "$current_branch" == "master" ]] || [[ "$current_branch" == "main" ]] || [[ "$current_branch" == "develop" ]]; then
    echo "⚠️  WARNING: Rebasing public branch '$current_branch'"
    echo "This may rewrite history. Continue? (y/N)"
    read -r response
    if [[ ! "$response" =~ ^[Yy]$ ]]; then
        echo "Rebase cancelled"
        exit 1
    fi
fi

# Run quick validation
if command -v make >/dev/null 2>&1; then
    make ci-precommit
fi

echo "✅ Pre-rebase validation passed"
EOF

# Make all hooks executable
chmod +x "$HOOKS_DIR"/*

log "✅ Git hooks installed:"
log "  - pre-commit: Fast validation (build, test, format)"
log "  - pre-push: Comprehensive CI validation"
log "  - post-commit: Optional smoke tests"
log "  - prepare-commit-msg: Conventional commit template"
log "  - post-merge: Integration validation"
log "  - pre-rebase: Safety checks for public branches"

echo ""
log "🎯 Hook Integration Features:"
log "  - Automatic CI pipeline integration"
log "  - Branch-specific validation levels"
log "  - Conventional commit message formatting"
log "  - Dependency change detection"
log "  - Safety checks for public branch operations"

echo ""
log "💡 To disable hooks temporarily:"
log "  git commit --no-verify"
log "  git push --no-verify"

echo ""
log "🔧 To customize hooks, edit files in: .git/hooks/"

# Test the hooks
echo ""
log "Testing hook installation..."

if [[ -x "$HOOKS_DIR/pre-commit" ]]; then
    log "✅ Pre-commit hook installed and executable"
else
    error "❌ Pre-commit hook installation failed"
fi

if [[ -x "$HOOKS_DIR/pre-push" ]]; then
    log "✅ Pre-push hook installed and executable"
else
    error "❌ Pre-push hook installation failed"
fi

log "🎉 Git hooks setup completed successfully!"
log "Next commit will use the new validation pipeline."