#!/bin/bash
# Foxhunt HFT Trading System - Production Deployment Script
# Simple, reliable deployment without Kubernetes complexity

set -euo pipefail

# Configuration
SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
PROJECT_ROOT="$(cd "${SCRIPT_DIR}/../.." && pwd)"
DEPLOY_DIR="/opt/foxhunt"
BACKUP_DIR="/opt/foxhunt/backups/$(date +%Y%m%d_%H%M%S)"
LOG_FILE="/home/jgrusewski/Work/foxhunt/logs-deploy.log"

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

# Logging function
log() {
    echo -e "[$(date '+%Y-%m-%d %H:%M:%S')] $1" | tee -a "${LOG_FILE}"
}

error() {
    log "${RED}ERROR: $1${NC}"
    exit 1
}

warning() {
    log "${YELLOW}WARNING: $1${NC}"
}

info() {
    log "${BLUE}INFO: $1${NC}"
}

success() {
    log "${GREEN}SUCCESS: $1${NC}"
}

# Check prerequisites
check_prerequisites() {
    info "Checking prerequisites..."

    # Check if running as root
    if [[ $EUID -ne 0 ]]; then
        error "This script must be run as root (use sudo)"
    fi

    # Check Docker
    if ! command -v docker &> /dev/null; then
        error "Docker is not installed"
    fi

    if ! command -v docker-compose &> /dev/null; then
        error "Docker Compose is not installed"
    fi

    # Check Rust/Cargo
    if ! command -v cargo &> /dev/null; then
        error "Cargo (Rust) is not installed"
    fi

    # Check systemctl
    if ! command -v systemctl &> /dev/null; then
        error "systemctl is not available (SystemD required)"
    fi

    success "Prerequisites check passed"
}

# Validate configuration
validate_config() {
    info "Validating configuration..."

    # Check if .env file exists
    if [[ ! -f "${PROJECT_ROOT}/docker/.env" ]]; then
        warning ".env file not found, copying template"
        cp "${PROJECT_ROOT}/docker/.env.template" "${PROJECT_ROOT}/docker/.env"
        error "Please edit ${PROJECT_ROOT}/docker/.env with your configuration and run again"
    fi

    # Validate required environment variables
    source "${PROJECT_ROOT}/docker/.env"

    local required_vars=(
        "POSTGRES_PASSWORD"
        "REDIS_PASSWORD"
        "INFLUXDB_PASSWORD"
        "INFLUXDB_TOKEN"
        "GRAFANA_ADMIN_PASSWORD"
    )

    for var in "${required_vars[@]}"; do
        if [[ -z "${!var:-}" ]]; then
            error "Required environment variable $var is not set in .env file"
        fi
    done

    success "Configuration validation passed"
}

# Create backup of current deployment
create_backup() {
    info "Creating backup of current deployment..."

    if [[ -d "${DEPLOY_DIR}" ]]; then
        mkdir -p "${BACKUP_DIR}"

        # Backup binaries
        if [[ -d "${DEPLOY_DIR}/bin" ]]; then
            cp -r "${DEPLOY_DIR}/bin" "${BACKUP_DIR}/"
        fi

        # Backup config
        if [[ -d "${DEPLOY_DIR}/config" ]]; then
            cp -r "${DEPLOY_DIR}/config" "${BACKUP_DIR}/"
        fi

        # Create backup manifest
        cat > "${BACKUP_DIR}/manifest.txt" << EOF
Backup created: $(date)
Source: ${DEPLOY_DIR}
Deployment version: $(cat "${DEPLOY_DIR}/VERSION" 2>/dev/null || echo "unknown")
EOF

        success "Backup created at ${BACKUP_DIR}"
    else
        info "No existing deployment found, skipping backup"
    fi
}

# Build the project
build_project() {
    info "Building Foxhunt HFT Trading System..."

    cd "${PROJECT_ROOT}"

    # Clean previous builds
    cargo clean

    # Build in release mode
    info "Building TLI binary..."
    cargo build --release --bin tli

    # Check if we have a backtesting binary
    if [[ -f "${PROJECT_ROOT}/backtesting/src/main.rs" ]]; then
        info "Building backtesting service..."
        cargo build --release --bin backtesting-service
    fi

    success "Build completed successfully"
}

# Deploy binaries and configuration
deploy_files() {
    info "Deploying files to ${DEPLOY_DIR}..."

    # Create deployment directory structure
    mkdir -p "${DEPLOY_DIR}"/{bin,config,logs,data,docker}

    # Deploy binaries
    cp "${PROJECT_ROOT}/target/release/tli" "${DEPLOY_DIR}/bin/"

    if [[ -f "${PROJECT_ROOT}/target/release/backtesting-service" ]]; then
        cp "${PROJECT_ROOT}/target/release/backtesting-service" "${DEPLOY_DIR}/bin/"
    fi

    # Deploy configuration
    cp -r "${PROJECT_ROOT}/config/"* "${DEPLOY_DIR}/config/" 2>/dev/null || true
    cp "${PROJECT_ROOT}/docker/docker-compose.enhanced.yml" "${DEPLOY_DIR}/docker/docker-compose.yml"
    cp "${PROJECT_ROOT}/docker/.env" "${DEPLOY_DIR}/docker/"

    # Create version file
    echo "$(date '+%Y-%m-%d %H:%M:%S') - $(git rev-parse HEAD 2>/dev/null || echo 'unknown')" > "${DEPLOY_DIR}/VERSION"

    # Set ownership
    chown -R foxhunt:foxhunt "${DEPLOY_DIR}"
    chmod +x "${DEPLOY_DIR}/bin/"*

    success "Files deployed successfully"
}

# Start database stack
start_database_stack() {
    info "Starting database stack..."

    cd "${DEPLOY_DIR}/docker"

    # Pull latest images
    docker-compose pull

    # Start database services
    docker-compose up -d postgres redis influxdb prometheus grafana

    # Wait for services to be healthy
    info "Waiting for database services to be ready..."
    local max_attempts=30
    local attempt=0

    while [[ $attempt -lt $max_attempts ]]; do
        if docker-compose ps --services --filter "status=running" | grep -q "postgres\|redis\|influxdb"; then
            success "Database stack is running"
            break
        fi

        sleep 5
        ((attempt++))
        info "Waiting for services... (${attempt}/${max_attempts})"
    done

    if [[ $attempt -eq $max_attempts ]]; then
        error "Database stack failed to start within expected time"
    fi
}

# Install and start SystemD services
setup_systemd_services() {
    info "Setting up SystemD services..."

    # Install service files
    "${PROJECT_ROOT}/deployment/systemd/install-services.sh"

    # Start database stack service
    systemctl start foxhunt-database-stack
    systemctl status foxhunt-database-stack --no-pager

    # Start TLI service
    systemctl start foxhunt-tli
    systemctl status foxhunt-tli --no-pager

    # Start backtesting service if available
    if [[ -f "${DEPLOY_DIR}/bin/backtesting-service" ]]; then
        systemctl start foxhunt-backtesting
        systemctl status foxhunt-backtesting --no-pager
    fi

    success "SystemD services configured and started"
}

# Run health checks
run_health_checks() {
    info "Running health checks..."

    local checks_passed=0
    local total_checks=5

    # Check database stack
    if systemctl is-active --quiet foxhunt-database-stack; then
        success "✓ Database stack is running"
        ((checks_passed++))
    else
        warning "✗ Database stack is not running"
    fi

    # Check TLI service
    if systemctl is-active --quiet foxhunt-tli; then
        success "✓ TLI service is running"
        ((checks_passed++))
    else
        warning "✗ TLI service is not running"
    fi

    # Check PostgreSQL
    if docker exec foxhunt-postgres pg_isready -U foxhunt &>/dev/null; then
        success "✓ PostgreSQL is healthy"
        ((checks_passed++))
    else
        warning "✗ PostgreSQL is not healthy"
    fi

    # Check Redis
    if docker exec foxhunt-redis redis-cli ping &>/dev/null; then
        success "✓ Redis is healthy"
        ((checks_passed++))
    else
        warning "✗ Redis is not healthy"
    fi

    # Check Prometheus
    if curl -s http://localhost:9090/-/ready &>/dev/null; then
        success "✓ Prometheus is healthy"
        ((checks_passed++))
    else
        warning "✗ Prometheus is not healthy"
    fi

    info "Health checks: ${checks_passed}/${total_checks} passed"

    if [[ $checks_passed -lt $total_checks ]]; then
        warning "Some health checks failed. Check logs for details."
        return 1
    fi

    success "All health checks passed!"
}

# Display deployment summary
show_deployment_summary() {
    info "Deployment Summary"
    echo "===================="
    echo "Deployment completed at: $(date)"
    echo "Deployment directory: ${DEPLOY_DIR}"
    echo "Backup directory: ${BACKUP_DIR}"
    echo ""
    echo "Services:"
    echo "  - TLI Terminal Interface: systemctl status foxhunt-tli"
    echo "  - Database Stack: systemctl status foxhunt-database-stack"
    if [[ -f "${DEPLOY_DIR}/bin/backtesting-service" ]]; then
        echo "  - Backtesting Service: systemctl status foxhunt-backtesting"
    fi
    echo ""
    echo "Web Interfaces:"
    echo "  - Grafana Dashboard: http://localhost:3000"
    echo "  - Prometheus: http://localhost:9090"
    echo "  - InfluxDB: http://localhost:8086"
    echo ""
    echo "Logs:"
    echo "  - TLI: journalctl -u foxhunt-tli -f"
    echo "  - Database Stack: docker-compose -f ${DEPLOY_DIR}/docker/docker-compose.yml logs -f"
    echo "  - Deployment: tail -f ${LOG_FILE}"
    echo ""
    echo "To rollback: ${SCRIPT_DIR}/rollback.sh ${BACKUP_DIR}"
}

# Main deployment function
main() {
    info "Starting Foxhunt HFT Trading System deployment..."

    check_prerequisites
    validate_config
    create_backup
    build_project
    deploy_files
    start_database_stack
    setup_systemd_services

    if run_health_checks; then
        success "Deployment completed successfully!"
    else
        warning "Deployment completed with warnings. Please check the health check results."
    fi

    show_deployment_summary
}

# Handle script arguments
case "${1:-deploy}" in
    "deploy")
        main
        ;;
    "health-check")
        run_health_checks
        ;;
    "start")
        systemctl start foxhunt-database-stack foxhunt-tli
        [[ -f "${DEPLOY_DIR}/bin/backtesting-service" ]] && systemctl start foxhunt-backtesting
        ;;
    "stop")
        systemctl stop foxhunt-tli foxhunt-backtesting foxhunt-database-stack 2>/dev/null || true
        ;;
    "restart")
        systemctl restart foxhunt-database-stack foxhunt-tli
        [[ -f "${DEPLOY_DIR}/bin/backtesting-service" ]] && systemctl restart foxhunt-backtesting
        ;;
    "status")
        systemctl status foxhunt-database-stack foxhunt-tli foxhunt-backtesting --no-pager 2>/dev/null || true
        ;;
    *)
        echo "Usage: $0 {deploy|health-check|start|stop|restart|status}"
        exit 1
        ;;
esac