#!/bin/bash
set -e  # Exit on any error

# Configuration — source of truth for all paths
DEPLOY_DIR="/opt/semblance"
FRONTEND_DEST="/var/www/html/semblance"
BACKEND_DIR="$DEPLOY_DIR/backend"
PYTHON_CMD="python3.13"

echo "======================================"
echo "Starting deployment..."
echo "======================================"

# ── Pre-flight checks ─────────────────────────────────────────────────────────

# Verify backend/.env exists (it is gitignored — must be provisioned manually)
if [ ! -f "$BACKEND_DIR/.env" ]; then
    echo ""
    echo "ERROR: $BACKEND_DIR/.env not found."
    echo "This file is not tracked in git and must be created manually on the server."
    echo "Copy backend/.env.example and fill in real values:"
    echo "  cp $BACKEND_DIR/.env.example $BACKEND_DIR/.env"
    echo "  nano $BACKEND_DIR/.env"
    exit 1
fi

# Verify required env vars are set in backend/.env
for VAR in SECRET_KEY JWT_SECRET_KEY OPENAI_API_KEY GEMINI_API_KEY; do
    if ! grep -q "^${VAR}=.\+" "$BACKEND_DIR/.env" 2>/dev/null; then
        echo ""
        echo "ERROR: $VAR is not set in $BACKEND_DIR/.env"
        exit 1
    fi
done
echo "✓ backend/.env present and required vars set"

# ── Step 1: Pull latest changes ───────────────────────────────────────────────
echo ""
echo "[1/7] Pulling latest changes from git..."
cd "$DEPLOY_DIR"
git pull

# ── Step 2: Set up frontend environment ──────────────────────────────────────
echo ""
echo "[2/7] Setting up frontend environment..."
cp .env.production .env

# ── Step 3: Set up Python virtual environment ─────────────────────────────────
echo ""
echo "[3/7] Setting up Python virtual environment..."
cd "$BACKEND_DIR"
if [ ! -d "venv" ]; then
    echo "Creating new virtual environment with $PYTHON_CMD..."
    $PYTHON_CMD -m venv venv
else
    echo "Virtual environment already exists."
fi

# ── Step 4: Install Python dependencies ──────────────────────────────────────
echo ""
echo "[4/7] Installing Python dependencies..."
source venv/bin/activate
pip install -r requirements.txt --quiet

# ── Step 5: Build and deploy frontend ────────────────────────────────────────
echo ""
echo "[5/7] Building and deploying frontend..."
cd "$DEPLOY_DIR"
npm install --silent
npm run build

echo "Cleaning deployment directory..."
rm -rf "$FRONTEND_DEST"/*
echo "Copying new build..."
cp -r dist/* "$FRONTEND_DEST/"

# ── Step 6: Ensure backend directories exist with correct ownership ───────────
echo ""
echo "[6/7] Creating backend directories..."
mkdir -p "$BACKEND_DIR/uploads"
mkdir -p "$BACKEND_DIR/temp"
sudo chown -R www-data:www-data "$BACKEND_DIR/uploads" "$BACKEND_DIR/temp"

# ── Step 7: Restart backend service ──────────────────────────────────────────
echo ""
echo "[7/7] Restarting backend service..."
sudo systemctl restart semblance.service

echo ""
echo "======================================"
echo "Deployment complete!"
echo "======================================"
echo ""
# Use || true so a non-active status doesn't cause set -e to abort with a confusing error
systemctl status semblance.service --no-pager || true