#!/bin/bash
# ============================================================================
# Environment Check Script for Task Reporter
# Validates all prerequisites required to run the development environment
# ============================================================================

# Note: Not using set -e because we handle errors explicitly with ERRORS counter

# Colors for output
RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[1;33m'
BLUE='\033[0;34m'
NC='\033[0m' # No Color

# Script directory (scripts are in project root)
SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
PROJECT_ROOT="$SCRIPT_DIR"

# Track overall status
ERRORS=0
WARNINGS=0

# Helper functions
print_header() {
    echo -e "\n${BLUE}=== $1 ===${NC}"
}

print_ok() {
    echo -e "${GREEN}[OK]${NC} $1"
}

print_error() {
    echo -e "${RED}[ERROR]${NC} $1"
    ((ERRORS++))
}

print_warn() {
    echo -e "${YELLOW}[WARN]${NC} $1"
    ((WARNINGS++))
}

print_info() {
    echo -e "${BLUE}[INFO]${NC} $1"
}

# Show help
show_help() {
    echo "Usage: $0 [OPTIONS]"
    echo ""
    echo "Validates the development environment for Task Reporter."
    echo ""
    echo "Options:"
    echo "  -h, --help     Show this help message"
    echo "  -q, --quiet    Only show errors and warnings"
    echo ""
    echo "Checks performed:"
    echo "  - Python version (3.10+)"
    echo "  - Node.js and npm"
    echo "  - Docker availability"
    echo "  - Virtual environment (venv/)"
    echo "  - Environment file (.env)"
    echo "  - Port availability (8000, 3000, 9000, 9001)"
}

# Parse arguments
QUIET=false
while [[ $# -gt 0 ]]; do
    case $1 in
        -h|--help)
            show_help
            exit 0
            ;;
        -q|--quiet)
            QUIET=true
            shift
            ;;
        *)
            echo "Unknown option: $1"
            show_help
            exit 1
            ;;
    esac
done

echo -e "${BLUE}============================================${NC}"
echo -e "${BLUE}  Task Reporter - Environment Check${NC}"
echo -e "${BLUE}============================================${NC}"

# ============================================================================
# Check Python version
# ============================================================================
print_header "Python"

if command -v python3 &> /dev/null; then
    PYTHON_VERSION=$(python3 -c 'import sys; print(f"{sys.version_info.major}.{sys.version_info.minor}")')
    PYTHON_MAJOR=$(echo "$PYTHON_VERSION" | cut -d. -f1)
    PYTHON_MINOR=$(echo "$PYTHON_VERSION" | cut -d. -f2)

    if [[ "$PYTHON_MAJOR" -ge 3 ]] && [[ "$PYTHON_MINOR" -ge 10 ]]; then
        print_ok "Python $PYTHON_VERSION detected"
    else
        print_error "Python 3.10+ required, found $PYTHON_VERSION"
    fi
else
    print_error "Python3 not found. Please install Python 3.10+"
fi

# ============================================================================
# Check Node.js and npm
# ============================================================================
print_header "Node.js"

if command -v node &> /dev/null; then
    NODE_VERSION=$(node --version)
    print_ok "Node.js $NODE_VERSION detected"
else
    print_error "Node.js not found. Please install Node.js 18+"
fi

if command -v npm &> /dev/null; then
    NPM_VERSION=$(npm --version)
    print_ok "npm $NPM_VERSION detected"
else
    print_error "npm not found. Please install npm"
fi

# ============================================================================
# Check Docker
# ============================================================================
print_header "Docker"

if command -v docker &> /dev/null; then
    DOCKER_VERSION=$(docker --version | cut -d' ' -f3 | tr -d ',')
    print_ok "Docker $DOCKER_VERSION detected"

    # Check if Docker daemon is running
    if docker info &> /dev/null; then
        print_ok "Docker daemon is running"
    else
        print_error "Docker daemon is not running. Please start Docker"
    fi
else
    print_error "Docker not found. Please install Docker"
fi

if command -v docker-compose &> /dev/null; then
    COMPOSE_VERSION=$(docker-compose --version | grep -oE '[0-9]+\.[0-9]+\.[0-9]+' | head -1)
    print_ok "docker-compose $COMPOSE_VERSION detected"
elif docker compose version &> /dev/null; then
    COMPOSE_VERSION=$(docker compose version | grep -oE '[0-9]+\.[0-9]+\.[0-9]+' | head -1)
    print_ok "docker compose (plugin) $COMPOSE_VERSION detected"
else
    print_error "docker-compose not found. Please install docker-compose"
fi

# ============================================================================
# Check Virtual Environment
# ============================================================================
print_header "Virtual Environment"

if [[ -d "$PROJECT_ROOT/venv" ]]; then
    print_ok "Virtual environment found at venv/"

    # Check if it has required packages
    if [[ -f "$PROJECT_ROOT/venv/bin/activate" ]]; then
        print_ok "venv/bin/activate exists"
    else
        print_warn "venv/bin/activate not found - venv may be corrupted"
    fi
else
    print_error "Virtual environment not found"
    print_info "Create it with: python3 -m venv venv"
    print_info "Then activate: source venv/bin/activate"
    print_info "And install: pip install -r requirements.txt"
fi

# ============================================================================
# Check Environment File
# ============================================================================
print_header "Environment File"

if [[ -f "$PROJECT_ROOT/.env" ]]; then
    print_ok ".env file exists"

    # Check for critical variables (use || true to prevent set -e from exiting)
    if grep -q "^FERNET_KEY=.\+" "$PROJECT_ROOT/.env" 2>/dev/null; then
        print_ok "FERNET_KEY is set"
    else
        print_warn "FERNET_KEY appears to be empty"
        print_info "Generate with: python -c \"from cryptography.fernet import Fernet; print(Fernet.generate_key().decode())\""
    fi

    if grep -q "^DATABASE_URL=" "$PROJECT_ROOT/.env" 2>/dev/null; then
        print_ok "DATABASE_URL is set"
    else
        print_warn "DATABASE_URL is not set"
    fi

    if grep -q "^MINIO_ENDPOINT=" "$PROJECT_ROOT/.env" 2>/dev/null; then
        print_ok "MINIO_ENDPOINT is set"
    else
        print_info "MINIO_ENDPOINT not in .env (will use defaults)"
    fi
else
    print_error ".env file not found"
    print_info "Copy from template: cp .env.example .env"
    print_info "Then edit .env and set required values"
fi

# ============================================================================
# Check Port Availability
# ============================================================================
print_header "Port Availability"

check_port() {
    local port=$1
    local service=$2

    if command -v ss &> /dev/null; then
        if ss -tuln | grep -q ":$port "; then
            PROCESS=$(ss -tulnp 2>/dev/null | grep ":$port " | awk '{print $NF}' | head -1)
            print_warn "Port $port ($service) is in use: $PROCESS"
        else
            print_ok "Port $port ($service) is available"
        fi
    elif command -v netstat &> /dev/null; then
        if netstat -tuln | grep -q ":$port "; then
            print_warn "Port $port ($service) is in use"
        else
            print_ok "Port $port ($service) is available"
        fi
    else
        print_info "Cannot check port $port - ss/netstat not available"
    fi
}

check_port 8000 "Backend API"
check_port 3000 "Frontend Dev"
check_port 9000 "MinIO S3"
check_port 9001 "MinIO Console"

# ============================================================================
# Summary
# ============================================================================
print_header "Summary"

if [[ $ERRORS -eq 0 ]] && [[ $WARNINGS -eq 0 ]]; then
    echo -e "${GREEN}All checks passed! Environment is ready.${NC}"
    exit 0
elif [[ $ERRORS -eq 0 ]]; then
    echo -e "${YELLOW}$WARNINGS warning(s) found. Environment may work but review warnings above.${NC}"
    exit 0
else
    echo -e "${RED}$ERRORS error(s) and $WARNINGS warning(s) found.${NC}"
    echo -e "${RED}Please fix the errors above before starting development.${NC}"
    exit 1
fi