#!/usr/bin/env bash
# ── MariaDB HA Demo — One-Command Deploy ────────────────
# Installs dependencies, deploys MariaDB cluster, starts the dashboard.
# Run as:  bash deploy.sh
set -euo pipefail

readonly SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
readonly DEMO_HOME="${SCRIPT_DIR}"

RED='\033[0;31m'
GREEN='\033[0;32m'
BLUE='\033[0;34m'
NC='\033[0m'

log()  { echo -e "${GREEN}[✓]${NC} $1"; }
warn() { echo -e "${RED}[!]${NC} $1"; }
info() { echo -e "${BLUE}[i]${NC} $1"; }

# ── Check prerequisites ──────────────────────────────────
command -v docker >/dev/null 2>&1 || {
    warn "Docker not found. Installing..."
    sudo apt-get update -qq && sudo apt-get install -y -qq docker.io docker-compose-v2
}
command -v python3 >/dev/null 2>&1 || {
    warn "Python3 not found. Installing..."
    sudo apt-get install -y -qq python3 python3-pip python3-venv
}
command -v mariadb >/dev/null 2>&1 || {
    warn "MariaDB client not found. Installing..."
    sudo apt-get install -y -qq mariadb-client
}

# ── Docker ───────────────────────────────────────────────
if ! systemctl is-active --quiet docker; then
    sudo systemctl enable --now docker
    log "Docker started"
fi

# ── Python venv ──────────────────────────────────────────
if [ ! -d "${DEMO_HOME}/venv" ]; then
    info "Creating Python virtual environment..."
    python3 -m venv "${DEMO_HOME}/venv"
    "${DEMO_HOME}/venv/bin/pip" install -q -r "${DEMO_HOME}/requirements.txt"
    log "Python dependencies installed"
fi

# ── Docker images ────────────────────────────────────────
info "Pulling Docker images..."
docker pull mariadb:latest -q 2>/dev/null &
docker pull mariadb/maxscale:latest -q 2>/dev/null &
wait
log "Docker images ready"

# ── Cluster ──────────────────────────────────────────────
chmod +x "${DEMO_HOME}/scripts/cluster.sh"
"${DEMO_HOME}/scripts/cluster.sh" start

# ── Systemd ──────────────────────────────────────────────
if [ -d /etc/systemd/system ]; then
    sudo cp "${DEMO_HOME}/scripts/mariadb-cluster.service" /etc/systemd/system/
    sudo cp "${DEMO_HOME}/scripts/mariadb-monitor.service" /etc/systemd/system/
    # Update paths in service files
    sudo sed -i "s|/home/engineer/mariadb-monitor|${DEMO_HOME}|g" \
        /etc/systemd/system/mariadb-cluster.service \
        /etc/systemd/system/mariadb-monitor.service
    sudo systemctl daemon-reload
    sudo systemctl enable mariadb-cluster.service mariadb-monitor.service 2>/dev/null || true
    log "Systemd services installed (auto-start on boot)"
fi

# ── Dashboard ────────────────────────────────────────────
"${DEMO_HOME}/venv/bin/python3" "${DEMO_HOME}/app.py" &
DASHBOARD_PID=$!
sleep 3

echo ""
echo "╔══════════════════════════════════════════════════════════╗"
echo "║          MariaDB HA Demo — Ready                        ║"
echo "╠══════════════════════════════════════════════════════════╣"
echo "║  Dashboard:    http://$(hostname -I | awk '{print $1}'):5000      ║"
echo "║  MaxScale GUI: http://$(hostname -I | awk '{print $1}'):5000/maxscale  ║"
echo "║  MaxScale API: http://127.0.0.1:8989                    ║"
echo "╠══════════════════════════════════════════════════════════╣"
echo "║  Cluster: 6 nodes (Cluster 1 + Cluster 2)               ║"
echo "║  Proxy:   MaxScale 24.02 (port 4000)                    ║"
echo "║  Monitor: HA-monitor + readwritesplit                   ║"
echo "╚══════════════════════════════════════════════════════════╝"
echo ""
echo "  Stop:  sudo systemctl stop mariadb-cluster"
echo "  Start: sudo systemctl start mariadb-cluster && sudo systemctl start mariadb-monitor"
echo ""
echo "  Dashboard PID: ${DASHBOARD_PID}"
echo "  Logs: journalctl -u mariadb-cluster -f"