#!/bin/bash
# ================================================
# Math Platform - Production Start Script
# ================================================

set -e

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

# Configuration
PROJECT_ROOT="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
DOCKER_COMPOSE_FILE="$PROJECT_ROOT/docker-compose.yml"
BACKUP_DIR="$PROJECT_ROOT/docker/backups"
LOG_DIR="$PROJECT_ROOT/docker/logs"

echo -e "${BLUE}============================================${NC}"
echo -e "${BLUE}Math Platform - Production Start${NC}"
echo -e "${BLUE}============================================${NC}"

# Create necessary directories
mkdir -p "$BACKUP_DIR"
mkdir -p "$LOG_DIR"
mkdir -p "$PROJECT_ROOT/pdfs/processed"

# Check if .env exists
if [ ! -f "$PROJECT_ROOT/.env" ]; then
    echo -e "${RED}Error: .env file not found!${NC}"
    echo -e "${YELLOW}Please copy .env.example to .env and configure it.${NC}"
    exit 1
fi

# Function to check if Docker is running
check_docker() {
    if ! docker info > /dev/null 2>&1; then
        echo -e "${RED}Error: Docker is not running!${NC}"
        exit 1
    fi
    echo -e "${GREEN}Docker is running${NC}"
}

# Function to check if docker-compose is available
check_docker_compose() {
    if ! command -v docker-compose &> /dev/null && ! docker compose version &> /dev/null; then
        echo -e "${RED}Error: docker-compose not found!${NC}"
        exit 1
    fi
    echo -e "${GREEN}Docker Compose is available${NC}"
}

# Function to backup database before starting
backup_database() {
    echo -e "${YELLOW}Creating database backup before starting...${NC}"
    TIMESTAMP=$(date +%Y%m%d_%H%M%S)
    BACKUP_FILE="$BACKUP_DIR/mathdb_backup_$TIMESTAMP.sql"

    if docker ps | grep -q math-postgres; then
        docker exec math-postgres pg_dump -U mathuser mathdb > "$BACKUP_FILE" 2>/dev/null || true
        if [ -f "$BACKUP_FILE" ] && [ -s "$BACKUP_FILE" ]; then
            echo -e "${GREEN}Backup created: $BACKUP_FILE${NC}"
            gzip "$BACKUP_FILE"
        else
            echo -e "${YELLOW}No existing database to backup (first run)${NC}"
        fi
    else
        echo -e "${YELLOW}Database container not running (first run)${NC}"
    fi
}

# Function to pull latest images
pull_images() {
    echo -e "${YELLOW}Pulling latest Docker images...${NC}"
    docker-compose -f "$DOCKER_COMPOSE_FILE" pull
}

# Function to build images
build_images() {
    echo -e "${YELLOW}Building Docker images...${NC}"
    docker-compose -f "$DOCKER_COMPOSE_FILE" build --no-cache
}

# Function to start services
start_services() {
    echo -e "${YELLOW}Starting services...${NC}"
    docker-compose -f "$DOCKER_COMPOSE_FILE" up -d

    echo -e "${GREEN}Services started successfully!${NC}"
}

# Function to wait for services to be healthy
wait_for_services() {
    echo -e "${YELLOW}Waiting for services to be healthy...${NC}"

    # Wait for PostgreSQL
    echo -n "Waiting for PostgreSQL..."
    timeout=60
    while [ $timeout -gt 0 ]; do
        if docker exec math-postgres pg_isready -U mathuser -d mathdb &> /dev/null; then
            echo -e " ${GREEN}OK${NC}"
            break
        fi
        echo -n "."
        sleep 2
        timeout=$((timeout-2))
    done

    if [ $timeout -le 0 ]; then
        echo -e " ${RED}FAILED${NC}"
        return 1
    fi

    # Wait for Backend
    echo -n "Waiting for Backend..."
    timeout=90
    while [ $timeout -gt 0 ]; do
        if docker exec math-backend wget -q -O /dev/null http://localhost:3001/health 2>/dev/null; then
            echo -e " ${GREEN}OK${NC}"
            break
        fi
        echo -n "."
        sleep 2
        timeout=$((timeout-2))
    done

    if [ $timeout -le 0 ]; then
        echo -e " ${YELLOW}TAKING LONGER THAN EXPECTED${NC}"
    fi

    # Wait for Frontend
    echo -n "Waiting for Frontend..."
    timeout=90
    while [ $timeout -gt 0 ]; do
        if docker exec math-frontend wget -q -O /dev/null http://localhost:3000 2>/dev/null; then
            echo -e " ${GREEN}OK${NC}"
            break
        fi
        echo -n "."
        sleep 2
        timeout=$((timeout-2))
    done

    if [ $timeout -le 0 ]; then
        echo -e " ${YELLOW}TAKING LONGER THAN EXPECTED${NC}"
    fi
}

# Function to run database migrations
run_migrations() {
    echo -e "${YELLOW}Running database migrations...${NC}"
    docker-compose -f "$DOCKER_COMPOSE_FILE" exec -T backend npx prisma migrate deploy || {
        echo -e "${YELLOW}Migration failed or already applied${NC}"
    }
}

# Function to show service status
show_status() {
    echo -e "\n${BLUE}============================================${NC}"
    echo -e "${BLUE}Service Status${NC}"
    echo -e "${BLUE}============================================${NC}"
    docker-compose -f "$DOCKER_COMPOSE_FILE" ps

    echo -e "\n${BLUE}============================================${NC}"
    echo -e "${BLUE}Access Information${NC}"
    echo -e "${BLUE}============================================${NC}"
    echo -e "${GREEN}Frontend:${NC}  http://localhost:3000"
    echo -e "${GREEN}Backend:${NC}   http://localhost:3001"
    echo -e "${GREEN}Nginx:${NC}     http://localhost:80"
    echo -e "\n${YELLOW}View logs with: docker-compose logs -f [service_name]${NC}"
    echo -e "${YELLOW}Stop services with: ./docker/stop.sh${NC}"
}

# Main execution
main() {
    check_docker
    check_docker_compose
    backup_database

    # Parse arguments
    REBUILD=false
    PULL=false

    while [[ $# -gt 0 ]]; do
        case $1 in
            --rebuild)
                REBUILD=true
                shift
                ;;
            --pull)
                PULL=true
                shift
                ;;
            *)
                echo -e "${RED}Unknown option: $1${NC}"
                echo "Usage: $0 [--rebuild] [--pull]"
                exit 1
                ;;
        esac
    done

    if [ "$PULL" = true ]; then
        pull_images
    fi

    if [ "$REBUILD" = true ]; then
        build_images
    fi

    start_services
    sleep 5
    wait_for_services
    run_migrations
    show_status

    echo -e "\n${GREEN}Math Platform started successfully!${NC}"
}

# Run main function
main "$@"