#!/bin/bash
set -e

##############################################################################
# H&M EMS Product Review Tool - Deployment Script
#
# This script is idempotent and can be run for both initial deployment
# and subsequent updates.
#
# Usage: sudo ./deploy.sh
##############################################################################

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

# Configuration
APP_DIR="/opt/hm_ems_report"
DATA_DIR="/opt/hm-ems-data"
WEB_DIR="/var/www/html/hm-ems-report"
BACKUP_DIR="${DATA_DIR}/backups"
SERVICE_NAME="hm-ems"
VENV_DIR="${APP_DIR}/venv"
LOG_DIR="/var/log/hm-ems"
USER="vadym.samoilenko"
GROUP="vadym.samoilenko"

# Logging functions
log_info() {
    echo -e "${GREEN}[INFO]${NC} $1"
}

log_warn() {
    echo -e "${YELLOW}[WARN]${NC} $1"
}

log_error() {
    echo -e "${RED}[ERROR]${NC} $1"
}

# Check if running as root
if [ "$EUID" -ne 0 ]; then
    log_error "Please run as root (use sudo)"
    exit 1
fi

log_info "Starting H&M EMS deployment..."

##############################################################################
# 1. Check user exists and create directories
##############################################################################
log_info "Checking user ${USER}..."

if ! id "${USER}" &>/dev/null; then
    log_error "User ${USER} does not exist. Please create it first or update USER variable in this script."
    exit 1
fi

log_info "Creating directories..."

mkdir -p "${DATA_DIR}/Master_Json"
mkdir -p "${DATA_DIR}/campaign_images"
mkdir -p "${BACKUP_DIR}"
mkdir -p "${WEB_DIR}"
mkdir -p "${LOG_DIR}"

log_info "Setting ownership to ${USER}:${GROUP}..."
chown -R ${USER}:${GROUP} "${DATA_DIR}"
chown -R ${USER}:${GROUP} "${WEB_DIR}"
chown -R ${USER}:${GROUP} "${LOG_DIR}"
chown -R ${USER}:${GROUP} "${APP_DIR}"

# Set proper permissions
chmod -R 755 "${DATA_DIR}"
chmod -R 755 "${WEB_DIR}"
chmod -R 755 "${APP_DIR}"

##############################################################################
# 2. Backup existing data
##############################################################################
if [ -d "${DATA_DIR}/Master_Json" ] && [ "$(ls -A ${DATA_DIR}/Master_Json)" ]; then
    TIMESTAMP=$(date +%Y%m%d_%H%M%S)
    BACKUP_FILE="${BACKUP_DIR}/backup_${TIMESTAMP}.tar.gz"

    log_info "Creating backup: ${BACKUP_FILE}"
    tar -czf "${BACKUP_FILE}" -C "${DATA_DIR}" Master_Json 2>/dev/null || true

    # Keep only last 10 backups
    cd "${BACKUP_DIR}"
    ls -t backup_*.tar.gz 2>/dev/null | tail -n +11 | xargs rm -f 2>/dev/null || true
    cd - > /dev/null
fi

##############################################################################
# 3. Verify git repository
##############################################################################
cd "${APP_DIR}"

if [ ! -d .git ]; then
    log_error "Not a git repository. Please clone the repo to ${APP_DIR} first"
    exit 1
fi

# Note: Git pull should be done manually before running this script
# Example: cd /opt/hm_ems_report && git pull
log_info "Using current code version (run 'git pull' manually before deploy if needed)"

##############################################################################
# 4. Setup Python virtual environment
##############################################################################
log_info "Setting up Python virtual environment..."

if [ ! -d "${VENV_DIR}" ]; then
    log_info "Creating new virtual environment..."
    python3 -m venv "${VENV_DIR}"
fi

# Activate venv and install dependencies
source "${VENV_DIR}/bin/activate"
pip install --upgrade pip
pip install -r requirements.txt

log_info "Python dependencies installed"

##############################################################################
# 5. Deploy frontend files
##############################################################################
log_info "Deploying frontend files..."

# Delete old files from web directory
rm -rf "${WEB_DIR}"/*

# Copy static files
cp -r static/* "${WEB_DIR}/"

# Set permissions
chown -R ${USER}:${GROUP} "${WEB_DIR}"
chmod -R 755 "${WEB_DIR}"

log_info "Frontend files deployed to ${WEB_DIR}"

##############################################################################
# 6. Install and configure systemd service
##############################################################################
log_info "Configuring systemd service..."

if [ -f "systemd/${SERVICE_NAME}.service" ]; then
    cp "systemd/${SERVICE_NAME}.service" "/etc/systemd/system/${SERVICE_NAME}.service"
    systemctl daemon-reload
    systemctl enable ${SERVICE_NAME}
    log_info "Systemd service configured"
else
    log_warn "Systemd service file not found, skipping"
fi

##############################################################################
# 7. Restart service
##############################################################################
log_info "Restarting application service..."

if systemctl is-active --quiet ${SERVICE_NAME}; then
    systemctl restart ${SERVICE_NAME}
    log_info "Service restarted"
else
    systemctl start ${SERVICE_NAME}
    log_info "Service started"
fi

# Wait a moment for service to start
sleep 2

##############################################################################
# 8. Health check
##############################################################################
log_info "Running health check..."

if systemctl is-active --quiet ${SERVICE_NAME}; then
    log_info "✓ Service is running"

    # Check if port is listening
    if ss -tlnp | grep -q ":5000"; then
        log_info "✓ Port 5000 is listening"

        # Check API endpoint
        if curl -sf http://localhost:5000/api/files > /dev/null 2>&1; then
            log_info "✓ API endpoint responding"
        else
            log_warn "API endpoint not responding yet (may need more time to start)"
        fi
    else
        log_warn "Port 5000 not listening yet"
    fi
else
    log_error "Service failed to start!"
    systemctl status ${SERVICE_NAME} --no-pager
    exit 1
fi

##############################################################################
# 9. Summary
##############################################################################
echo ""
log_info "========================================="
log_info "Deployment completed successfully!"
log_info "========================================="
echo ""
echo "Application URL: https://ai-sandbox.oliver.solutions/hm-ems-report/"
echo "API endpoint: https://ai-sandbox.oliver.solutions/hm-ems-report/api/files"
echo ""
echo "Useful commands:"
echo "  - Check status:  sudo systemctl status ${SERVICE_NAME}"
echo "  - View logs:     sudo journalctl -u ${SERVICE_NAME} -f"
echo "  - Restart:       sudo systemctl restart ${SERVICE_NAME}"
echo "  - Stop:          sudo systemctl stop ${SERVICE_NAME}"
echo ""
echo "Data location:   ${DATA_DIR}"
echo "Web files:       ${WEB_DIR}"
echo "Backups:         ${BACKUP_DIR}"
echo ""