#!/bin/bash
source ~/.bashrc
# Prerequisites Check Script
# Validates system requirements before deployment

set -e

# Colors for output
RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[1;33m'
NC='\033[0m'

CHECK_TYPE="${1:-all}"

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_pass() {
    echo -e "${GREEN}✓${NC} $1"
}

check_fail() {
    echo -e "${RED}✗${NC} $1"
    return 1
}

check_proxmox() {
    log_info "Checking Proxmox VE installation..."
    
    if command -v pvecm &> /dev/null && command -v pvesm &> /dev/null; then
        check_pass "Proxmox VE tools installed"
        pveversion | head -1
    else
        check_fail "Proxmox VE tools not found"
        return 1
    fi
}

check_network() {
    log_info "Checking network configuration..."
    
    if ip link show vmbr0 &>/dev/null; then
        check_pass "Bridge vmbr0 exists"
        ip addr show vmbr0 | grep "inet " || check_warn "vmbr0 has no IP address"
    else
        check_warn "Bridge vmbr0 not found (may need network configuration)"
    fi
}

check_azure_cli() {
    log_info "Checking Azure CLI installation..."
    
    if command -v az &> /dev/null; then
        check_pass "Azure CLI installed"
        az version | head -1
        
        # Check if logged in
        if az account show &>/dev/null; then
            check_pass "Azure CLI authenticated"
            az account show --query "{subscriptionId:id, tenantId:tenantId}" -o table
        else
            check_warn "Azure CLI not authenticated (run 'az login')"
        fi
    else
        check_warn "Azure CLI not installed (required for Azure Arc onboarding)"
    fi
}

check_kubectl() {
    log_info "Checking kubectl installation..."
    
    if command -v kubectl &> /dev/null; then
        check_pass "kubectl installed"
        kubectl version --client --short
    else
        check_warn "kubectl not installed (required for Kubernetes management)"
    fi
}

check_helm() {
    log_info "Checking Helm installation..."
    
    if command -v helm &> /dev/null; then
        check_pass "Helm installed"
        helm version --short
    else
        check_warn "Helm not installed (required for GitOps deployments)"
    fi
}

check_docker() {
    log_info "Checking Docker installation..."
    
    if command -v docker &> /dev/null; then
        check_pass "Docker installed"
        docker --version
        
        if docker ps &>/dev/null; then
            check_pass "Docker daemon running"
        else
            check_warn "Docker daemon not running"
        fi
    else
        check_warn "Docker not installed (required for Git/GitLab deployment)"
    fi
}

check_terraform() {
    log_info "Checking Terraform installation..."
    
    if command -v terraform &> /dev/null; then
        check_pass "Terraform installed"
        terraform version | head -1
    else
        check_warn "Terraform not installed (optional, for IaC)"
    fi
}

check_system_resources() {
    log_info "Checking system resources..."
    
    # Check memory
    TOTAL_MEM=$(free -g | awk '/^Mem:/{print $2}')
    if [ "$TOTAL_MEM" -ge 8 ]; then
        check_pass "Memory: ${TOTAL_MEM}GB (minimum 8GB recommended)"
    else
        check_warn "Memory: ${TOTAL_MEM}GB (8GB+ recommended)"
    fi
    
    # Check disk space
    DISK_SPACE=$(df -h / | awk 'NR==2 {print $4}')
    check_info "Available disk space: $DISK_SPACE"
}

check_info() {
    echo -e "${GREEN}ℹ${NC} $1"
}

main() {
    log_info "Running prerequisites check: $CHECK_TYPE"
    
    case "$CHECK_TYPE" in
        proxmox)
            check_proxmox
            check_network
            ;;
        azure)
            check_azure_cli
            ;;
        kubernetes)
            check_kubectl
            check_helm
            ;;
        git)
            check_docker
            ;;
        all)
            check_proxmox
            check_network
            check_azure_cli
            check_kubectl
            check_helm
            check_docker
            check_terraform
            check_system_resources
            ;;
        *)
            log_error "Unknown check type: $CHECK_TYPE"
            log_info "Available types: proxmox, azure, kubernetes, git, all"
            exit 1
            ;;
    esac
    
    log_info "Prerequisites check completed"
}

main "$@"