#!/bin/bash
set -e

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

echo "=== ModComms Deployment ==="
echo "Working directory: $SCRIPT_DIR"

# --- Check prerequisites ---
echo ""
echo "[Prerequisites] Checking required tools..."

check_command() {
    if ! command -v "$1" &> /dev/null; then
        echo "Error: $1 is not installed"
        exit 1
    fi
    echo "  ✓ $1"
}

check_command git
check_command node
check_command npm
check_command docker

# --- Load deployment configuration ---
if [ -f .env.deploy ]; then
    source .env.deploy
    echo "  ✓ .env.deploy loaded"
else
    echo ""
    echo "Error: .env.deploy not found"
    echo "Create it from the template:"
    echo "  cp .env.deploy.example .env.deploy"
    echo "  nano .env.deploy"
    exit 1
fi

# Validate required variables
if [ -z "$FRONTEND_DEPLOY_DIR" ]; then
    echo "Error: FRONTEND_DEPLOY_DIR not set in .env.deploy"
    exit 1
fi

# Set defaults for docker compose variables
COMPOSE_PROJECT_NAME="${COMPOSE_PROJECT_NAME:-modcomms}"
BACKEND_PORT="${BACKEND_PORT:-8000}"
POSTGRES_PORT="${POSTGRES_PORT:-5432}"
POSTGRES_USER="${POSTGRES_USER:-modcomms}"
POSTGRES_PASSWORD="${POSTGRES_PASSWORD:-modcomms_dev}"
POSTGRES_DB="${POSTGRES_DB:-modcomms}"
echo "  Environment: ${COMPOSE_PROJECT_NAME} (backend:${BACKEND_PORT}, postgres:${POSTGRES_PORT})"

# Create .env file for docker compose (so manual docker compose commands work)
cat > .env << EOF
# Auto-generated by deploy.sh - do not edit manually
# Edit .env.deploy instead and re-run deploy.sh
COMPOSE_PROJECT_NAME=${COMPOSE_PROJECT_NAME}
BACKEND_PORT=${BACKEND_PORT}
POSTGRES_PORT=${POSTGRES_PORT}
POSTGRES_USER=${POSTGRES_USER}
POSTGRES_PASSWORD=${POSTGRES_PASSWORD}
POSTGRES_DB=${POSTGRES_DB}
EOF
echo "  ✓ .env created for docker compose"

# --- Check backend/.env exists (required for GEMINI_API_KEY) ---
if [ ! -f backend/.env ]; then
    if [ -f backend/.env.example ]; then
        echo ""
        echo "Error: backend/.env not found"
        echo "Create it from the template:"
        echo "  cp backend/.env.example backend/.env"
        echo "  nano backend/.env  # Add your GEMINI_API_KEY"
        exit 1
    else
        echo "Error: backend/.env not found and no template available"
        exit 1
    fi
fi
echo "  ✓ backend/.env exists"

# Validate that critical backend env vars are actually set (not placeholders)
check_backend_env() {
    local var_name="$1"
    local value
    value=$(grep -E "^${var_name}=" backend/.env | cut -d= -f2- | tr -d '"' | tr -d "'")
    if [ -z "$value" ] || [[ "$value" == *"your_"* ]]; then
        echo ""
        echo "Error: ${var_name} is not configured in backend/.env"
        echo "  Open backend/.env and set a real value for ${var_name}"
        exit 1
    fi
    echo "  ✓ ${var_name} is set"
}

check_backend_env GEMINI_API_KEY
check_backend_env AZURE_TENANT_ID
check_backend_env AZURE_CLIENT_ID
# DATABASE_URL is intentionally omitted here — it is injected by docker-compose.yml

# --- 1. Pull latest code (skip if not a git repo or no remote) ---
echo ""
echo "[1/6] Updating code..."
if [ -d .git ]; then
    if git remote -v | grep -q origin; then
        # Discard local changes to package-lock.json (regenerated by npm install anyway)
        git checkout -- frontend/package-lock.json 2>/dev/null || true
        git pull || echo "Warning: git pull failed, continuing with local code"
    else
        echo "  No remote configured, skipping git pull"
    fi
else
    echo "  Not a git repository, skipping git pull"
fi

# --- 2. Build frontend ---
echo ""
echo "[2/6] Building frontend..."
cd frontend

# Install dependencies (npm install is idempotent)
npm install

# Check that .env.local exists (must be created manually with credentials)
if [ ! -f .env.local ]; then
    echo ""
    echo "Error: frontend/.env.local not found"
    echo "Create it manually with your environment-specific values:"
    echo ""
    echo "  cat > frontend/.env.local << 'EOF'"
    echo "  VITE_BACKEND_WS_URL=wss://your-domain.com/ws/analyze"
    echo "  VITE_BACKEND_URL=https://your-domain.com"
    echo "  VITE_AZURE_CLIENT_ID=your_azure_client_id"
    echo "  VITE_AZURE_TENANT_ID=your_azure_tenant_id"
    echo "  VITE_AZURE_REDIRECT_URI=https://your-domain.com"
    echo "  EOF"
    echo ""
    exit 1
fi
echo "  ✓ .env.local exists"

npm run build
cd "$SCRIPT_DIR"

# --- 3. Deploy frontend to Apache ---
echo ""
echo "[3/6] Deploying frontend to ${FRONTEND_DEPLOY_DIR}..."

# Create directory if it doesn't exist
sudo mkdir -p "$FRONTEND_DEPLOY_DIR"

# Clear existing files (safe deletion with variable check)
if [ -n "$FRONTEND_DEPLOY_DIR" ] && [ -d "$FRONTEND_DEPLOY_DIR" ]; then
    sudo find "$FRONTEND_DEPLOY_DIR" -mindepth 1 -delete 2>/dev/null || true
fi

# Copy new build
sudo cp -r frontend/dist/* "$FRONTEND_DEPLOY_DIR/"
sudo chown -R www-data:www-data "$FRONTEND_DEPLOY_DIR"
echo "  ✓ Frontend deployed"

# --- 4. Update backend configuration ---
echo ""
echo "[4/6] Updating backend configuration..."

# Update CORS_ORIGINS if specified
if [ -n "$CORS_ORIGINS" ]; then
    if grep -q "^CORS_ORIGINS=" backend/.env; then
        sed -i "s|^CORS_ORIGINS=.*|CORS_ORIGINS=${CORS_ORIGINS}|" backend/.env
    else
        echo "CORS_ORIGINS=${CORS_ORIGINS}" >> backend/.env
    fi
    echo "  ✓ CORS_ORIGINS updated"
fi

# --- 5. Build containers and run database migrations ---
echo ""
echo "[5/6] Building containers and running database migrations..."

# Build image (always rebuild to pick up code changes)
docker compose build

# Start PostgreSQL first and wait for it to be healthy
echo "  Starting PostgreSQL..."
docker compose up -d postgres

echo "  Waiting for PostgreSQL to be ready..."
for i in {1..30}; do
    if docker compose exec -T postgres pg_isready -U "${POSTGRES_USER}" -d "${POSTGRES_DB}" > /dev/null 2>&1; then
        echo "  ✓ PostgreSQL is ready"
        break
    fi
    if [ $i -eq 30 ]; then
        echo "  Error: PostgreSQL failed to start"
        docker compose logs postgres
        exit 1
    fi
    sleep 1
done

# Run database migrations
echo "  Running database migrations..."
if docker compose run --rm backend alembic upgrade head; then
    echo "  ✓ Database migrations complete"
else
    echo "  Error: Database migrations failed"
    exit 1
fi

# --- 6. Start backend service ---
echo ""
echo "[6/6] Starting backend service..."

# Start backend container (force recreate to ensure new image is used)
docker compose up -d --force-recreate backend

# Wait for health check
echo "  Waiting for backend to be healthy..."
for i in {1..30}; do
    if curl -sf "http://localhost:${BACKEND_PORT}/health" > /dev/null 2>&1; then
        echo "  ✓ Backend is healthy"
        break
    fi
    if [ $i -eq 30 ]; then
        echo "  Warning: Backend health check timed out"
    fi
    sleep 1
done

# --- Deployment summary ---
echo ""
echo "========================================="
echo "        Deployment Complete!"
echo "========================================="
echo ""
echo "Environment:  ${COMPOSE_PROJECT_NAME}"
echo "Frontend:     ${FRONTEND_DEPLOY_DIR}"
echo "Backend:      http://localhost:${BACKEND_PORT}"
echo ""
docker compose ps --format "table {{.Name}}\t{{.Status}}\t{{.Ports}}"
echo ""
echo "Health check:"
curl -s "http://localhost:${BACKEND_PORT}/health" && echo "" || echo "Warning: Backend not responding"