#!/bin/bash
set -euo pipefail

# Phase 6, Plan 1, Task 4: Automated Deployment Script
# Usage: ./deploy.sh [production|staging|development] [--rebuild]
# Purpose: Single-command deployment with Docker Compose, pre-flight checks, and health validation

DEPLOYMENT_ENV="${1:-production}"
REBUILD_FLAG="${2:---no-rebuild}"

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

# Logging functions
log_info() { echo -e "${BLUE}[INFO]${NC} $1"; }
log_success() { echo -e "${GREEN}[SUCCESS]${NC} $1"; }
log_warn() { echo -e "${YELLOW}[WARN]${NC} $1"; }
log_error() { echo -e "${RED}[ERROR]${NC} $1"; exit 1; }

log_info "=== TFM aInventory Deployment Script ==="
log_info "Environment: $DEPLOYMENT_ENV"
log_info "Rebuild: $REBUILD_FLAG"

# ============================================================================
# STEP 1: Pre-flight checks
# ============================================================================
log_info "Step 1/10: Running pre-flight checks..."

command -v docker &> /dev/null || log_error "Docker not installed. Please install Docker 24.0+"
log_success "  ✓ Docker is installed"

command -v docker-compose &> /dev/null || log_error "Docker Compose not installed. Please install Docker Compose 2.0+"
log_success "  ✓ Docker Compose is installed"

[[ -f "docker-compose.yml" ]] || log_error "docker-compose.yml not found in current directory"
log_success "  ✓ docker-compose.yml found"

[[ -f "inventory.env" ]] || log_warn "inventory.env not found; attempting to create from template..."
if [[ ! -f "inventory.env" ]] && [[ -f "inventory.env.template" ]]; then
  cp inventory.env.template inventory.env
  log_success "  ✓ inventory.env created from template (review and customize)"
elif [[ ! -f "inventory.env" ]]; then
  log_error "inventory.env not found and no template available. Create inventory.env before deploying."
fi

# ============================================================================
# STEP 2: Validate environment file
# ============================================================================
log_info "Step 2/10: Validating inventory.env..."

if [[ ! -f ".env.validation.sh" ]]; then
  log_warn "  .env.validation.sh not found; skipping validation"
else
  bash .env.validation.sh || log_error "Environment validation failed"
fi

log_success "  ✓ Environment variables validated"

# ============================================================================
# STEP 3: Check port availability
# ============================================================================
log_info "Step 3/10: Checking port availability..."

# Source inventory.env to get port values
source inventory.env

BACKEND_PORT=${BACKEND_PORT:-8000}
FRONTEND_PORT=${FRONTEND_PORT:-3000}
BACKEND_SSL_PORT=${BACKEND_SSL_PORT:-8918}
FRONTEND_SSL_PORT=${FRONTEND_SSL_PORT:-8919}

for port in "$BACKEND_PORT" "$FRONTEND_PORT" "$BACKEND_SSL_PORT" "$FRONTEND_SSL_PORT"; do
  if command -v netstat &> /dev/null; then
    if netstat -tuln 2>/dev/null | grep -q ":$port "; then
      log_error "Port $port is already in use. Choose a different port in inventory.env"
    fi
  else
    log_warn "  netstat not available; skipping port check (ensure ports are available)"
  fi
done

log_success "  ✓ All required ports are available"

# ============================================================================
# STEP 4: Check disk space
# ============================================================================
log_info "Step 4/10: Checking disk space..."

AVAILABLE_SPACE=$(df . | awk 'NR==2 {print $4}')
REQUIRED_SPACE=$((10 * 1024 * 1024)) # 10GB in KB

if [[ $AVAILABLE_SPACE -lt $REQUIRED_SPACE ]]; then
  log_warn "  Available space: $(($AVAILABLE_SPACE / 1024 / 1024))GB (recommended: 10GB+)"
else
  log_success "  ✓ Sufficient disk space available ($(($AVAILABLE_SPACE / 1024 / 1024))GB)"
fi

# ============================================================================
# STEP 5: Build or pull images
# ============================================================================
log_info "Step 5/10: Building Docker images..."

if [[ "$REBUILD_FLAG" == "--rebuild" ]]; then
  log_info "  Building with --no-cache (full rebuild)..."
  docker-compose build --no-cache || log_error "Docker build failed"
else
  log_info "  Building with layer cache (incremental)..."
  docker-compose build || log_error "Docker build failed"
fi

log_success "  ✓ Docker images built successfully"

# ============================================================================
# STEP 6: Create data directories
# ============================================================================
log_info "Step 6/10: Preparing data directories..."

mkdir -p data logs config
mkdir -p data/caddy_data data/caddy_config
chmod -R 777 data logs config

log_success "  ✓ Data directories created with proper permissions"

# ============================================================================
# STEP 7: Initialize database
# ============================================================================
log_info "Step 7/10: Checking database initialization..."

if [[ ! -f "data/inventory.db" ]]; then
  log_info "  Database not found; will be initialized on first backend startup"
  log_success "  ✓ Database initialization scheduled"
else
  log_success "  ✓ Existing database found; reusing"
fi

# ============================================================================
# STEP 8: Start services
# ============================================================================
log_info "Step 8/10: Starting Docker services..."

docker-compose up -d || log_error "Failed to start Docker services"
log_success "  ✓ Services started in background"

# ============================================================================
# STEP 9: Wait for health checks
# ============================================================================
log_info "Step 9/10: Waiting for services to become healthy (max 60 seconds)..."

max_attempts=30
attempt=0
all_healthy=false

while [[ $attempt -lt $max_attempts ]]; do
  # Check if all 3 services are healthy
  if docker-compose ps | grep -q "healthy.*healthy.*healthy"; then
    all_healthy=true
    break
  fi

  attempt=$((attempt + 1))
  remaining=$((max_attempts - attempt))
  log_info "  Waiting... ($remaining attempts remaining)"
  sleep 2
done

if [[ "$all_healthy" == true ]]; then
  log_success "  ✓ All services are healthy"
else
  log_warn "Services did not become healthy within timeout. Checking logs..."
  docker-compose logs --tail=50 || true
  log_error "Service health check timeout. Review logs above."
fi

# ============================================================================
# STEP 10: Verify connectivity
# ============================================================================
log_info "Step 10/10: Verifying service connectivity..."

if curl -sf "http://localhost:${BACKEND_PORT}/health" &> /dev/null; then
  log_success "  ✓ Backend API responding at http://localhost:${BACKEND_PORT}/health"
else
  log_warn "  Backend health check failed; services may still be initializing"
fi

if curl -sf "http://localhost:${FRONTEND_PORT}/" &> /dev/null; then
  log_success "  ✓ Frontend responding at http://localhost:${FRONTEND_PORT}"
else
  log_warn "  Frontend check failed; container may still be initializing"
fi

# ============================================================================
# Summary
# ============================================================================
echo ""
echo -e "${GREEN}╔════════════════════════════════════════════════════════════╗${NC}"
echo -e "${GREEN}║${NC}  Deployment completed successfully!                      ${GREEN}║${NC}"
echo -e "${GREEN}╚════════════════════════════════════════════════════════════╝${NC}"
echo ""
echo "Access points:"
echo "  Frontend (HTTP):  http://localhost:${FRONTEND_PORT}"
echo "  Backend (HTTP):   http://localhost:${BACKEND_PORT}"
echo "  API Docs:         http://localhost:${BACKEND_PORT}/docs"
echo "  Frontend (HTTPS): https://localhost:${FRONTEND_SSL_PORT}"
echo "  Backend (HTTPS):  https://localhost:${BACKEND_SSL_PORT}"
echo ""
echo "Useful commands:"
echo "  View logs:     docker-compose logs -f"
echo "  Stop services: docker-compose down"
echo "  Restart:       docker-compose restart"
echo "  Status:        docker-compose ps"
echo ""
echo "For deployment in production ($DEPLOYMENT_ENV):"
echo "  • Review and update JWT_SECRET_KEY in inventory.env"
echo "  • Configure firewall to expose only required ports"
echo "  • Set up automated backups (see docs/DEPLOYMENT_QUICKSTART.md)"
echo "  • Monitor logs regularly: docker-compose logs -f"
echo ""
log_success "Deployment ready!"