#!/bin/bash
# GT 2.0 Mac ARM64 Installer
# Installation script for macOS with Apple Silicon (M1/M2/M3+)
# Version: 1.0.0

set -e

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

# Configuration
INSTALLER_VERSION="1.0.0"
INSTALL_DIR="${HOME}/GT-2.0"
MIN_MACOS_VERSION="12"
MIN_RAM_GB=16
MIN_DISK_GB=20
GITHUB_REPO="https://github.com/GT-Edge-AI-Internal/gt-ai-os-community.git"
RELEASE_URL="https://api.github.com/repos/GT-Edge-AI-Internal/gt-ai-os-community/releases/latest"

# Flags
UNATTENDED=false
SKIP_DOCKER_CHECK=false
USE_RELEASE=false
BRANCH="main"
RUNNING_FROM_REPO=false

# Functions
print_header() {
    echo ""
    echo -e "${BLUE}================================================================${NC}"
    echo -e "${BLUE}  GT AI OS Community Edition${NC}"
    echo -e "${BLUE}  Mac ARM64 Installer v${INSTALLER_VERSION}${NC}"
    echo -e "${BLUE}================================================================${NC}"
    echo ""
}

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

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

print_warning() {
    echo -e "${YELLOW}⚠ $1${NC}"
}

print_info() {
    echo -e "${BLUE}ℹ $1${NC}"
}

show_help() {
    cat << EOF
Usage: $0 [OPTIONS]

Install GT 2.0 Enterprise AI Platform on macOS with Apple Silicon

OPTIONS:
    -h, --help              Show this help message
    -v, --version           Show installer version
    -u, --unattended        Run in non-interactive mode
    -d, --dir PATH          Installation directory (default: ${INSTALL_DIR})
    -b, --branch BRANCH     Git branch to clone (default: main)
    --skip-docker-check     Skip Docker Desktop installation check
    --use-release           Download latest release instead of cloning git repo

EXAMPLES:
    # Interactive installation
    $0

    # Unattended installation with custom directory
    $0 --unattended --dir /opt/gt2

    # Use pre-built release
    $0 --use-release

EOF
}

parse_args() {
    while [[ $# -gt 0 ]]; do
        case $1 in
            -h|--help)
                show_help
                exit 0
                ;;
            -v|--version)
                echo "GT 2.0 Mac Installer v${INSTALLER_VERSION}"
                exit 0
                ;;
            -u|--unattended)
                UNATTENDED=true
                shift
                ;;
            -d|--dir)
                INSTALL_DIR="$2"
                shift 2
                ;;
            -b|--branch)
                BRANCH="$2"
                shift 2
                ;;
            --skip-docker-check)
                SKIP_DOCKER_CHECK=true
                shift
                ;;
            --use-release)
                USE_RELEASE=true
                shift
                ;;
            *)
                print_error "Unknown option: $1"
                show_help
                exit 1
                ;;
        esac
    done
}

# Detect if running from within an already-cloned GT repo
detect_existing_repo() {
    # Get the directory where the script is located
    local script_dir="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
    local repo_root="$(dirname "$script_dir")"

    # Check if this looks like a GT repo (has key files)
    if [ -f "$repo_root/docker-compose.yml" ] && \
       [ -d "$repo_root/apps" ] && \
       [ -d "$repo_root/.git" ]; then
        print_info "Detected: Running from within cloned repository"
        INSTALL_DIR="$repo_root"
        RUNNING_FROM_REPO=true
        print_success "Using existing repo at: ${INSTALL_DIR}"
    fi
}

check_macos_version() {
    print_info "Checking macOS version..."

    local macos_version=$(sw_vers -productVersion | cut -d '.' -f 1)

    if [ "$macos_version" -lt "$MIN_MACOS_VERSION" ]; then
        print_error "macOS $MIN_MACOS_VERSION (Monterey) or higher required (found: $macos_version)"
        exit 1
    fi

    print_success "macOS version: $(sw_vers -productVersion)"
}

check_architecture() {
    print_info "Checking CPU architecture..."

    local arch=$(uname -m)

    if [ "$arch" != "arm64" ]; then
        print_error "This installer requires Apple Silicon (arm64), found: $arch"
        print_info "For Intel Macs, please use the x86_64 installer"
        exit 1
    fi

    print_success "Architecture: arm64 (Apple Silicon)"
}

check_ram() {
    print_info "Checking available RAM..."

    local ram_bytes=$(sysctl -n hw.memsize)
    local ram_gb=$((ram_bytes / 1024 / 1024 / 1024))

    if [ "$ram_gb" -lt "$MIN_RAM_GB" ]; then
        print_error "Minimum ${MIN_RAM_GB}GB RAM required (found: ${ram_gb}GB)"
        exit 1
    fi

    print_success "RAM: ${ram_gb}GB"
}

check_disk_space() {
    print_info "Checking available disk space..."

    local available_gb=$(df -g "${HOME}" | tail -1 | awk '{print $4}')

    if [ "$available_gb" -lt "$MIN_DISK_GB" ]; then
        print_error "Minimum ${MIN_DISK_GB}GB free disk space required (found: ${available_gb}GB)"
        exit 1
    fi

    print_success "Available disk space: ${available_gb}GB"
}

check_docker() {
    if [ "$SKIP_DOCKER_CHECK" = true ]; then
        print_warning "Skipping Docker Desktop check (--skip-docker-check)"
        return
    fi

    print_info "Checking for Docker Desktop..."

    if ! command -v docker &> /dev/null; then
        print_warning "Docker Desktop not found"

        if [ "$UNATTENDED" = false ]; then
            read -p "Install Docker Desktop via Homebrew? (y/n): " install_docker
            if [ "$install_docker" = "y" ]; then
                install_docker_desktop
            else
                print_error "Docker Desktop is required. Install manually from https://www.docker.com/products/docker-desktop"
                exit 1
            fi
        else
            print_error "Docker Desktop required but not found (unattended mode)"
            exit 1
        fi
    else
        print_success "Docker Desktop found: $(docker --version)"

        # Check if Docker daemon is running
        if ! docker info &> /dev/null; then
            print_warning "Docker Desktop is installed but not running"
            print_info "Please start Docker Desktop and run this installer again"
            exit 1
        fi

        print_success "Docker daemon is running"
    fi
}

install_docker_desktop() {
    print_info "Installing Docker Desktop via Homebrew..."

    # Check if Homebrew is installed
    if ! command -v brew &> /dev/null; then
        print_info "Installing Homebrew..."
        /bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"
    fi

    # Install Docker Desktop
    brew install --cask docker

    print_success "Docker Desktop installed"
    print_info "Please start Docker Desktop from Applications and run this installer again"
    exit 0
}

cleanup_existing_containers() {
    # Find all containers with gentwo- prefix (running or stopped)
    local existing_containers=$(docker ps -a --filter "name=gentwo-" --format "{{.Names}}" 2>/dev/null || true)

    if [ -n "$existing_containers" ]; then
        print_warning "Found existing GT 2.0 containers"

        # Stop running containers
        print_info "Stopping existing containers..."
        docker ps -q --filter "name=gentwo-" | xargs docker stop 2>/dev/null || true

        # Remove all containers
        print_info "Removing existing containers..."
        docker ps -aq --filter "name=gentwo-" | xargs docker rm -f 2>/dev/null || true

        print_success "Existing containers removed"
    fi

    # Also clean up orphaned volumes and networks
    # Match both internal (gt-20, gt2) and community (gt-ai-os-community) naming
    print_info "Cleaning up volumes..."
    docker volume ls -q --filter "name=gt-20" --filter "name=gt2" --filter "name=gt-ai-os-community" | xargs docker volume rm 2>/dev/null || true

    print_info "Cleaning up networks..."
    docker network ls -q --filter "name=gt2" --filter "name=gt-ai-os-community" | xargs docker network rm 2>/dev/null || true
}

check_existing_installation() {
    # Check for existing installation BEFORE any cleanup
    if [ -d "$INSTALL_DIR" ]; then
        print_warning "Existing installation found: ${INSTALL_DIR}"

        # Check for existing containers too
        local existing_containers=$(docker ps -a --filter "name=gentwo-" --format "{{.Names}}" 2>/dev/null || true)
        if [ -n "$existing_containers" ]; then
            print_info "Running containers: $(echo $existing_containers | tr '\n' ' ')"
        fi

        if [ "$UNATTENDED" = false ]; then
            echo ""
            read -p "Remove existing installation and reinstall? (y/n): " remove_existing
            if [ "$remove_existing" != "y" ]; then
                print_error "Installation cancelled"
                exit 1
            fi
        fi

        print_info "Removing existing installation..."
        return 0  # Proceed with cleanup
    fi

    return 0  # No existing installation
}

create_installation_directory() {
    # Remove existing directory if it exists (user already confirmed in check_existing_installation)
    if [ -d "$INSTALL_DIR" ]; then
        rm -rf "$INSTALL_DIR"
    fi

    mkdir -p "$INSTALL_DIR"
    print_success "Installation directory created: ${INSTALL_DIR}"
}

download_gt2() {
    print_info "Downloading GT 2.0..."

    if [ "$USE_RELEASE" = true ]; then
        print_info "Downloading latest release..."

        # Get latest release download URL
        local release_url=$(curl -s "$RELEASE_URL" | grep "tarball_url" | cut -d '"' -f 4)

        if [ -z "$release_url" ]; then
            print_error "Failed to fetch latest release"
            exit 1
        fi

        # Download and extract
        curl -L "$release_url" -o "${INSTALL_DIR}/gt2.tar.gz"
        tar -xzf "${INSTALL_DIR}/gt2.tar.gz" -C "$INSTALL_DIR" --strip-components=1
        rm "${INSTALL_DIR}/gt2.tar.gz"

        print_success "Release downloaded and extracted"
    else
        print_info "Cloning from Git repository (branch: ${BRANCH})..."

        git clone --depth 1 -b "$BRANCH" "$GITHUB_REPO" "$INSTALL_DIR"

        print_success "Repository cloned (branch: ${BRANCH})"
    fi
}

# Try to authenticate Docker with GHCR using gh CLI (optional)
try_ghcr_auth() {
    # Check if gh CLI is available and authenticated
    if ! command -v gh &>/dev/null; then
        return 1
    fi

    if ! gh auth status &>/dev/null 2>&1; then
        return 1
    fi

    local gh_user=$(gh api user --jq '.login' 2>/dev/null)
    local gh_token=$(gh auth token 2>/dev/null)

    if [ -n "$gh_user" ] && [ -n "$gh_token" ]; then
        if echo "$gh_token" | docker login ghcr.io -u "$gh_user" --password-stdin &>/dev/null; then
            print_success "Authenticated with GHCR as $gh_user"
            return 0
        fi
    fi

    return 1
}

pull_docker_images() {
    print_info "Pulling Docker images (this may take several minutes)..."

    cd "$INSTALL_DIR"

    # Try pull without auth first (works for public repos)
    local pull_output
    if pull_output=$(docker compose pull 2>&1); then
        print_success "Images pulled from registry"
        return
    fi

    # Check if auth error (private repo)
    if echo "$pull_output" | grep -qi "unauthorized\|denied\|403"; then
        print_info "Registry requires authentication..."

        # Try gh CLI auth if available
        if try_ghcr_auth; then
            if docker compose pull 2>&1; then
                print_success "Images pulled after authentication"
                return
            fi
        fi
    fi

    # Fallback to local build
    print_info "Building images locally (this takes longer on first install)..."
    docker compose build
    print_success "Images built successfully"
}

start_services() {
    print_info "Starting GT 2.0 services..."

    cd "$INSTALL_DIR"

    # Create required directories for bind mounts
    mkdir -p volumes/tenants/test/tablespaces
    mkdir -p volumes/tenants/test/files

    docker compose up -d

    print_success "Services started"
}

wait_for_health() {
    print_info "Waiting for services to become healthy (this may take 2-3 minutes)..."

    local max_wait=300
    local elapsed=0

    while [ $elapsed -lt $max_wait ]; do
        local healthy_count=0
        local total_services=5

        # Check Control Panel backend
        if curl -sf http://localhost:8001/health > /dev/null 2>&1; then
            ((healthy_count++))
        fi

        # Check Tenant backend
        if curl -sf http://localhost:8002/health > /dev/null 2>&1; then
            ((healthy_count++))
        fi

        # Check Resource Cluster
        if curl -sf http://localhost:8004/health > /dev/null 2>&1; then
            ((healthy_count++))
        fi

        # Check Control Panel frontend
        if curl -sf http://localhost:3001 > /dev/null 2>&1; then
            ((healthy_count++))
        fi

        # Check Tenant frontend
        if curl -sf http://localhost:3002 > /dev/null 2>&1; then
            ((healthy_count++))
        fi

        if [ $healthy_count -eq $total_services ]; then
            print_success "All services are healthy!"
            return 0
        fi

        echo -n "."
        sleep 5
        ((elapsed+=5))
    done

    echo ""
    print_warning "Some services may still be starting. Check with: docker compose ps"
}

create_desktop_shortcut() {
    if [ "$UNATTENDED" = false ]; then
        read -p "Create desktop shortcut? (y/n): " create_shortcut
        if [ "$create_shortcut" != "y" ]; then
            return
        fi
    else
        return
    fi

    print_info "Creating desktop shortcut..."

    # Create an app bundle for GT 2.0
    local app_dir="${HOME}/Desktop/GT-2.0.app/Contents/MacOS"
    mkdir -p "$app_dir"

    cat > "${app_dir}/GT-2.0" << 'EOF'
#!/bin/bash
open "http://localhost:3002"
EOF

    chmod +x "${app_dir}/GT-2.0"

    print_success "Desktop shortcut created"
}

display_access_info() {
    echo ""
    echo -e "${GREEN}================================================================${NC}"
    echo -e "${GREEN}  GT 2.0 Installation Complete!${NC}"
    echo -e "${GREEN}================================================================${NC}"
    echo ""
    echo -e "${BLUE}Access URLs:${NC}"
    echo -e "  Control Panel:  ${GREEN}http://localhost:3001${NC}"
    echo -e "  Tenant App:     ${GREEN}http://localhost:3002${NC}"
    echo ""
    echo -e "${BLUE}Default Credentials:${NC}"
    echo -e "  Username: ${GREEN}gtadmin@test.com${NC}"
    echo -e "  Password: ${GREEN}Test@123${NC}"
    echo ""
    echo -e "${BLUE}Installation Directory:${NC} ${INSTALL_DIR}"
    echo ""
    echo -e "${BLUE}Useful Commands:${NC}"
    echo "  View logs:      cd ${INSTALL_DIR} && docker compose logs -f"
    echo "  Stop services:  cd ${INSTALL_DIR} && docker compose down"
    echo "  Start services: cd ${INSTALL_DIR} && docker compose up -d"
    echo "  View status:    cd ${INSTALL_DIR} && docker compose ps"
    echo ""
    echo -e "${GREEN}Enjoy GT 2.0!${NC}"
    echo ""
}

cleanup_on_error() {
    print_error "Installation failed!"

    if [ -d "$INSTALL_DIR" ]; then
        print_info "Cleaning up..."
        cd "$INSTALL_DIR"
        docker compose down -v 2>/dev/null || true
        cd ..
        rm -rf "$INSTALL_DIR"
    fi

    exit 1
}

setup_demo_data() {
    print_info "Setting up model configurations..."

    cd "$INSTALL_DIR"

    if [ -f "scripts/demo/setup-demo-data.sh" ]; then
        chmod +x scripts/demo/setup-demo-data.sh
        ./scripts/demo/setup-demo-data.sh
        print_success "Model configurations complete"
    else
        print_warning "Model config script not found, skipping"
    fi
}

generate_security_tokens() {
    print_info "Generating security tokens..."

    cd "$INSTALL_DIR"

    # Use centralized secrets library if available
    if [ -f "scripts/lib/secrets.sh" ]; then
        source scripts/lib/secrets.sh
        generate_all_secrets ".env"
        print_success "Generated all required secrets"
    else
        # Fallback to inline generation for standalone installer
        local env_file=".env"

        # Create .env if it doesn't exist
        if [ ! -f "$env_file" ]; then
            touch "$env_file"
        fi

        # Generate SERVICE_AUTH_TOKEN if not already set
        if ! grep -q "^SERVICE_AUTH_TOKEN=" "$env_file" 2>/dev/null; then
            local service_token=$(openssl rand -hex 32)
            echo "SERVICE_AUTH_TOKEN=${service_token}" >> "$env_file"
            print_success "Generated SERVICE_AUTH_TOKEN"
        else
            print_info "SERVICE_AUTH_TOKEN already configured"
        fi

        # Generate JWT_SECRET if not already set
        if ! grep -q "^JWT_SECRET=" "$env_file" 2>/dev/null; then
            local jwt_secret=$(openssl rand -hex 32)
            echo "JWT_SECRET=${jwt_secret}" >> "$env_file"
            print_success "Generated JWT_SECRET"
        fi

        # Generate MASTER_ENCRYPTION_KEY if not already set
        if ! grep -q "^MASTER_ENCRYPTION_KEY=" "$env_file" 2>/dev/null; then
            if command -v python3 &> /dev/null && python3 -c "from cryptography.fernet import Fernet" 2>/dev/null; then
                local encryption_key=$(python3 -c "from cryptography.fernet import Fernet; print(Fernet.generate_key().decode())")
            else
                local encryption_key=$(openssl rand -base64 32)
            fi
            echo "MASTER_ENCRYPTION_KEY=${encryption_key}" >> "$env_file"
            print_success "Generated MASTER_ENCRYPTION_KEY"
        fi

        # Generate API_KEY_ENCRYPTION_KEY if not already set
        if ! grep -q "^API_KEY_ENCRYPTION_KEY=" "$env_file" 2>/dev/null; then
            if command -v python3 &> /dev/null && python3 -c "from cryptography.fernet import Fernet" 2>/dev/null; then
                local encryption_key=$(python3 -c "from cryptography.fernet import Fernet; print(Fernet.generate_key().decode())")
            else
                local encryption_key=$(openssl rand -base64 32)
            fi
            echo "API_KEY_ENCRYPTION_KEY=${encryption_key}" >> "$env_file"
            print_success "Generated API_KEY_ENCRYPTION_KEY"
        fi

        # Generate database passwords if not already set
        if ! grep -q "^ADMIN_POSTGRES_PASSWORD=" "$env_file" 2>/dev/null; then
            local admin_pw=$(openssl rand -base64 24 | tr -dc 'a-zA-Z0-9' | head -c 32)
            echo "ADMIN_POSTGRES_PASSWORD=${admin_pw}" >> "$env_file"
            print_success "Generated ADMIN_POSTGRES_PASSWORD"
        fi

        if ! grep -q "^TENANT_POSTGRES_PASSWORD=" "$env_file" 2>/dev/null; then
            local tenant_pw=$(openssl rand -base64 24 | tr -dc 'a-zA-Z0-9' | head -c 32)
            echo "TENANT_POSTGRES_PASSWORD=${tenant_pw}" >> "$env_file"
            print_success "Generated TENANT_POSTGRES_PASSWORD"
        fi
    fi
}

run_migrations() {
    print_info "Running database migrations..."

    cd "$INSTALL_DIR"

    # Source migration functions if available
    if [ -f "scripts/lib/migrations.sh" ] && [ -f "scripts/lib/common.sh" ]; then
        source scripts/lib/common.sh
        source scripts/lib/migrations.sh

        if run_all_migrations; then
            print_success "Database migrations completed"
        else
            print_warning "Some migrations may have failed - check logs"
        fi
    else
        print_warning "Migration scripts not found, skipping migrations"
    fi
}

# Main installation flow
main() {
    trap cleanup_on_error ERR

    parse_args "$@"

    print_header

    # Detect if running from within an already-cloned repo
    detect_existing_repo

    # Pre-flight checks
    check_macos_version
    check_architecture
    check_ram
    check_disk_space
    check_docker

    # Check for existing installation FIRST (prompts user before any cleanup)
    # Skip if we're running from within the repo we'd be checking
    if [ "$RUNNING_FROM_REPO" = false ]; then
        check_existing_installation
    fi

    # Now safe to cleanup (user has confirmed or no existing installation)
    cleanup_existing_containers

    # Installation - skip clone if already in repo
    if [ "$RUNNING_FROM_REPO" = false ]; then
        create_installation_directory
        download_gt2
    fi

    generate_security_tokens
    pull_docker_images
    start_services
    wait_for_health

    # Post-installation
    setup_demo_data
    run_migrations  # Apply any migrations not in init scripts (idempotent)
    create_desktop_shortcut
    display_access_info
}

# Run installer
main "$@"