#!/bin/bash
#
# Pre-commit hook for MEV Bot V2
# Ensures code quality and consistency before commits
#
# Install: ln -sf ../../.git-hooks/pre-commit .git/hooks/pre-commit
#

set -e

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

echo -e "${GREEN}🔍 Running pre-commit checks...${NC}"
echo ""

# ==============================================================================
# 1. CHECK BRANCH NAME
# ==============================================================================
BRANCH_NAME=$(git branch --show-current)

if [[ "$BRANCH_NAME" == "feature/v2-prep" ]] || [[ "$BRANCH_NAME" == "master" ]]; then
    echo -e "${YELLOW}⚠️  Warning: Committing to protected branch: $BRANCH_NAME${NC}"
    echo -e "${YELLOW}   Consider creating a feature branch instead${NC}"
    echo ""
fi

if [[ "$BRANCH_NAME" =~ ^feature/v2/ ]]; then
    # Validate branch naming convention
    if [[ ! "$BRANCH_NAME" =~ ^feature/v2/[a-z0-9-]+/[A-Z0-9]+-[0-9]+-[a-z0-9-]+$ ]]; then
        echo -e "${YELLOW}⚠️  Branch name doesn't follow convention:${NC}"
        echo -e "${YELLOW}   feature/v2/<component>/<TASK-ID>-<description>${NC}"
        echo ""
    fi
fi

# ==============================================================================
# 2. CHECK FOR MERGE CONFLICTS
# ==============================================================================
echo -e "${GREEN}📋 Checking for merge conflicts...${NC}"
if git diff --cached --name-only | xargs grep -l "^<<<<<<< HEAD" 2>/dev/null; then
    echo -e "${RED}❌ Merge conflict markers found${NC}"
    echo -e "${RED}   Resolve conflicts before committing${NC}"
    exit 1
fi
echo -e "${GREEN}✅ No merge conflicts${NC}"
echo ""

# ==============================================================================
# 3. CHECK FOR FORBIDDEN PATTERNS
# ==============================================================================
echo -e "${GREEN}🔒 Checking for secrets and forbidden patterns...${NC}"

# Check for common secret patterns
if git diff --cached --name-only -z | xargs -0 grep -E "password|secret|api[_-]?key|private[_-]?key|token" --include="*.go" 2>/dev/null | grep -v "test" | grep -v "example"; then
    echo -e "${RED}❌ Potential secrets found${NC}"
    echo -e "${RED}   Remove secrets before committing${NC}"
    exit 1
fi

# Check for debugging statements
if git diff --cached --name-only -z | xargs -0 grep -E "fmt\.Println|log\.Println|panic\(|TODO.*URGENT|FIXME.*CRITICAL" --include="*.go" 2>/dev/null; then
    echo -e "${YELLOW}⚠️  Warning: Found debugging statements or urgent TODOs${NC}"
    echo -e "${YELLOW}   Consider removing or creating issues for them${NC}"
    echo ""
fi

echo -e "${GREEN}✅ No forbidden patterns found${NC}"
echo ""

# ==============================================================================
# 4. GO MOD TIDY CHECK
# ==============================================================================
if [ -f "go.mod" ]; then
    echo -e "${GREEN}📦 Checking if go.mod is tidy...${NC}"

    # Save current go.mod and go.sum
    cp go.mod go.mod.backup
    cp go.sum go.sum.backup

    # Run go mod tidy
    go mod tidy

    # Check if anything changed
    if ! diff -q go.mod go.mod.backup > /dev/null 2>&1 || ! diff -q go.sum go.sum.backup > /dev/null 2>&1; then
        echo -e "${YELLOW}⚠️  go.mod or go.sum was not tidy${NC}"
        echo -e "${YELLOW}   Auto-fixed and staged${NC}"
        git add go.mod go.sum
    fi

    # Clean up backups
    rm -f go.mod.backup go.sum.backup

    echo -e "${GREEN}✅ Dependencies are tidy${NC}"
    echo ""
fi

# ==============================================================================
# 5. CODE FORMATTING
# ==============================================================================
echo -e "${GREEN}🎨 Checking code formatting...${NC}"

# Get list of staged Go files
STAGED_GO_FILES=$(git diff --cached --name-only --diff-filter=ACM | grep "\.go$" || true)

if [ -n "$STAGED_GO_FILES" ]; then
    # Check formatting
    UNFORMATTED=$(gofmt -l $STAGED_GO_FILES 2>/dev/null || true)

    if [ -n "$UNFORMATTED" ]; then
        echo -e "${YELLOW}⚠️  Auto-formatting files:${NC}"
        echo "$UNFORMATTED"

        # Auto-format files
        echo "$UNFORMATTED" | xargs gofmt -w -s

        # Re-stage formatted files
        echo "$UNFORMATTED" | xargs git add

        echo -e "${GREEN}✅ Code formatted and re-staged${NC}"
    else
        echo -e "${GREEN}✅ All files properly formatted${NC}"
    fi
else
    echo -e "${GREEN}ℹ️  No Go files to format${NC}"
fi
echo ""

# ==============================================================================
# 6. RUN TESTS ON CHANGED FILES
# ==============================================================================
if [ -n "$STAGED_GO_FILES" ]; then
    echo -e "${GREEN}🧪 Running tests on changed packages...${NC}"

    # Get unique package directories
    PACKAGES=$(echo "$STAGED_GO_FILES" | xargs -n1 dirname | sort -u | sed 's/$/\/.../')

    # Run tests with timeout
    if ! go test -short -timeout=2m $PACKAGES 2>&1; then
        echo -e "${RED}❌ Tests failed${NC}"
        echo -e "${RED}   Fix tests before committing${NC}"
        exit 1
    fi

    echo -e "${GREEN}✅ Tests passed${NC}"
else
    echo -e "${GREEN}ℹ️  No Go files changed, skipping tests${NC}"
fi
echo ""

# ==============================================================================
# 7. RUN GO VET
# ==============================================================================
if [ -n "$STAGED_GO_FILES" ]; then
    echo -e "${GREEN}🔍 Running go vet...${NC}"

    if ! go vet ./... 2>&1; then
        echo -e "${RED}❌ go vet found issues${NC}"
        echo -e "${RED}   Fix issues before committing${NC}"
        exit 1
    fi

    echo -e "${GREEN}✅ go vet passed${NC}"
fi
echo ""

# ==============================================================================
# 8. CHECK FILE SIZES
# ==============================================================================
echo -e "${GREEN}📏 Checking file sizes...${NC}"

LARGE_FILES=$(git diff --cached --name-only | xargs -I {} sh -c 'if [ -f "{}" ]; then stat -f%z "{}" 2>/dev/null || stat -c%s "{}" 2>/dev/null; fi' | awk '$1 > 1048576 {print}' || true)

if [ -n "$LARGE_FILES" ]; then
    echo -e "${YELLOW}⚠️  Warning: Large files detected (>1MB)${NC}"
    echo -e "${YELLOW}   Consider if these should be committed${NC}"
    git diff --cached --name-only | while read file; do
        size=$(stat -f%z "$file" 2>/dev/null || stat -c%s "$file" 2>/dev/null)
        if [ "$size" -gt 1048576 ]; then
            size_mb=$(echo "scale=2; $size / 1048576" | bc)
            echo -e "${YELLOW}   $file: ${size_mb}MB${NC}"
        fi
    done
    echo ""
fi

echo -e "${GREEN}✅ File size check complete${NC}"
echo ""

# ==============================================================================
# 9. FINAL SUMMARY
# ==============================================================================
echo -e "${GREEN}╔══════════════════════════════════════╗${NC}"
echo -e "${GREEN}║  ✅ PRE-COMMIT CHECKS PASSED ✅      ║${NC}"
echo -e "${GREEN}╚══════════════════════════════════════╝${NC}"
echo ""
echo -e "${GREEN}Proceeding with commit...${NC}"

exit 0