#!/bin/bash

# Must be run with root privileges

# Error handling
set -e
trap 'echo "Error on line $LINENO. Exit code: $?"' ERR

# Configuration
INSTALL_DIR="/docker/paperless-ngx"
COMPOSE_FILE="${INSTALL_DIR}/docker-compose.yml"
LOG_FILE="/var/log/paperless-install.log"

# Utility functions
log_message() {
    local message="[$(date '+%Y-%m-%d %H:%M:%S')] $1"
    echo "$message"
    echo "$message" >> "$LOG_FILE"
}

show_container_status() {
    log_message "Current container statuses:"
    echo "----------------------------------------"
    docker compose ps --format "table {{.Name}}\t{{.Status}}\t{{.Ports}}"
    echo "----------------------------------------"
}

check_service_status() {
    local service=$1
    local container_name="paperless-ngx-${service}-1"  # Fixed naming convention
    
    if ! docker ps -q -f name="$container_name" >/dev/null 2>&1; then
        return 1
    fi
    
    local status=$(docker inspect -f '{{.State.Status}}' "$container_name" 2>/dev/null)
    if [ "$status" != "running" ]; then
        return 1
    fi
    
    # Only perform additional health checks for specific services
    case "$service" in
        "webserver")
            if ! curl -sf http://localhost:8000 >/dev/null 2>&1; then
                return 1
            fi
            ;;
        "db")
            # Optional: Add PostgreSQL specific check if needed
            docker exec "$container_name" pg_isready -U paperless >/dev/null 2>&1 || return 1
            ;;
        "broker")
            # Redis broker only needs container running status check
            return 0
            ;;
    esac
    
    return 0
}

verify_all_services() {
    local services=("broker" "db" "webserver")
    local failed_services=()
    
    for service in "${services[@]}"; do
        case "$service" in
            "broker")
                # Just check if Redis is running, no wait needed
                if ! check_service_status "$service"; then
                    failed_services+=("$service")
                fi
                ;;
            *)
                log_message "Checking $service service..."
                if ! check_service_status "$service"; then
                    failed_services+=("$service")
                fi
                ;;
        esac
    done
    
    if [ ${#failed_services[@]} -ne 0 ]; then
        log_message "The following services are not running properly: ${failed_services[*]}"
        return 1
    fi
    
    log_message "All services are running properly"
    return 0
}

check_docker_version() {
    local current_version=$(docker --version | cut -d ' ' -f3 | cut -d ',' -f1)
    log_message "Current Docker version: $current_version"
    
    # Check for updates
    apt-get update >/dev/null 2>&1
    local available_version=$(apt-cache policy docker-ce | grep Candidate | cut -d ' ' -f4)
    
    if [ "$current_version" != "$available_version" ]; then
        log_message "New Docker version available: $available_version"
        read -p "Do you want to upgrade Docker? (y/N) " -n 1 -r
        echo
        if [[ $REPLY =~ ^[Yy]$ ]]; then
            apt-get install -y docker-ce docker-ce-cli containerd.io
        fi
    fi
}

redeploy_service() {
    local service=$1
    log_message "Redeploying $service..."
    
    cd "$INSTALL_DIR"
    docker compose stop "$service"
    docker compose rm -f "$service"
    docker compose up -d "$service"
    
    case "$service" in
        "broker")
            # Redis broker needs no health wait
            log_message "Redis broker redeployed"
            return 0
            ;;
        "db")
            # Wait for database to be ready
            local retries=0
            while ! check_service_status "$service" && [ $retries -lt 5 ]; do
                log_message "Waiting for database to be ready..."
                sleep 5
                retries=$((retries + 1))
            done
            ;;
        "webserver")
            # Wait for webserver to be healthy
            local retries=0
            while ! check_service_status "$service" && [ $retries -lt 5 ]; do
                log_message "Waiting for webserver to become healthy..."
                sleep 10
                retries=$((retries + 1))
            done
            ;;
    esac
    
    if [ $retries -eq 5 ]; then
        log_message "Failed to redeploy $service after 5 attempts"
        return 1
    fi
    
    log_message "$service redeployed successfully"
    return 0
}

backup_existing_data() {
    if [ -d "$INSTALL_DIR" ]; then
        local backup_dir="${INSTALL_DIR}_backup_$(date +%Y%m%d_%H%M%S)"
        log_message "Creating backup of existing installation at $backup_dir"
        cp -r "$INSTALL_DIR" "$backup_dir"
    fi
}

check_existing_installation() {
    log_message "Checking existing Paperless-ngx installation..."
    
    if [ -f "$COMPOSE_FILE" ]; then
        log_message "Existing installation found"
        show_container_status
        
        if verify_all_services; then
            log_message "? All services are running correctly"
            log_message "? Paperless-ngx is accessible at http://localhost:8000"
            log_message "? Redis and PostgreSQL containers are properly isolated"
            return 0
        else
            log_message "? Service issues detected. Starting recovery process..."
            return 1
        fi
    fi
    return 1
}

# Main script execution starts here

# Check if script is run as root
if [ "$EUID" -ne 0 ]; then 
    echo "Please run as root"
    exit 1
fi

# Initialize log file
mkdir -p "$(dirname "$LOG_FILE")"
touch "$LOG_FILE"
log_message "Starting Paperless-ngx installation/verification script"

# Check if Docker is installed
if ! command -v docker &> /dev/null; then
    log_message "Docker not found. Installing Docker..."
    curl -fsSL https://get.docker.com -o get-docker.sh
    sh get-docker.sh
    apt-get update
    apt-get install -y docker-compose-plugin
    log_message "Docker installed successfully"
else
    log_message "Docker already installed"
    check_docker_version
fi

# Check existing installation or proceed with new installation
if check_existing_installation; then
    exit 0
else
    if [ -f "$COMPOSE_FILE" ]; then
        # Attempt to recover existing installation
        backup_existing_data
        
        # Attempt to redeploy failed services
        for service in broker db webserver; do
            if ! check_service_status "$service"; then
                if ! redeploy_service "$service"; then
                    log_message "Failed to redeploy $service. Manual intervention may be required."
                    exit 1
                fi
            fi
        done
    else
        # New installation
        log_message "Starting new Paperless-ngx installation"
        
        # Create installation directory
        mkdir -p "$INSTALL_DIR"
        cd "$INSTALL_DIR"
        
        # Create docker-compose.yml
        cat > docker-compose.yml <<'EOF'
version: "3.4"
services:
  broker:
    image: redis:7
    restart: unless-stopped
    networks:
      - paperless_internal
    expose:
      - 6379
    volumes:
      - redisdata:/data

  db:
    image: postgres:15
    restart: unless-stopped
    networks:
      - paperless_internal
    expose:
      - 5432
    volumes:
      - pgdata:/var/lib/postgresql/data
    environment:
      POSTGRES_DB: paperless
      POSTGRES_USER: paperless
      POSTGRES_PASSWORD: paperless

  webserver:
    image: ghcr.io/paperless-ngx/paperless-ngx:latest
    restart: unless-stopped
    networks:
      - paperless_internal
      - paperless_external
    depends_on:
      - db
      - broker
    ports:
      - "8000:8000"
    healthcheck:
      test: ["CMD", "curl", "-f", "http://localhost:8000"]
      interval: 30s
      timeout: 10s
      retries: 5
    volumes:
      - data:/usr/src/paperless/data
      - media:/usr/src/paperless/media
      - ./export:/usr/src/paperless/export
      - ./consume:/usr/src/paperless/consume
    environment:
      PAPERLESS_REDIS: redis://broker:6379
      PAPERLESS_DBHOST: db
      PAPERLESS_DB_USER: paperless
      PAPERLESS_DB_PASSWORD: paperless
      PAPERLESS_DB_NAME: paperless
      PAPERLESS_TIME_ZONE: Europe/London
      PAPERLESS_OCR_LANGUAGE: eng
      PAPERLESS_SECRET_KEY: change-this-key
      PAPERLESS_URL: https://your-domain.com

networks:
  paperless_internal:
    internal: true  # Only accessible within Docker
  paperless_external:  # For external access to webserver

volumes:
  data:
    name: paperless_data
  media:
    name: paperless_media
  pgdata:
    name: paperless_pgdata
  redisdata:
    name: paperless_redisdata
EOF

        # Create required directories and set permissions
        mkdir -p export consume
        chown -R 1000:1000 export consume
        
        # Start services
        log_message "Starting Paperless-ngx services..."
        docker compose up -d
        
        # Give services more time to initialize on first deployment
        log_message "Waiting for services to initialize (this may take a minute)..."
        sleep 30  # Initial wait for containers to start
        
        # Additional wait loop with status checks
        for i in {1..6}; do  # Try for up to 1 minute more
            if docker compose ps | grep -q "healthy"; then
                break  # Exit loop if containers are healthy
            fi
            log_message "Still waiting for services to be ready... (attempt $i/6)"
            sleep 10
        done
        if verify_all_services; then
            log_message "? Installation completed successfully!"
            show_container_status
            
            # Create superuser
            log_message "Creating superuser account..."
            if docker compose run --rm webserver createsuperuser; then
                log_message "? Superuser created successfully"
                log_message "? You can access Paperless-ngx at http://localhost:8000"
            else
                log_message "? Failed to create superuser. You can create one later using:"
                log_message "  docker compose run --rm webserver createsuperuser"
                log_message "? You can access Paperless-ngx at http://localhost:8000"
            fi
            
            log_message "Important next steps:"
            log_message "1. Change the PAPERLESS_URL in docker-compose.yml to your domain"
            log_message "2. Change the PAPERLESS_SECRET_KEY to a random string"
            log_message "3. Set up a reverse proxy in CloudPanel"
            log_message "4. Create SSL certificate for your domain"
        else
            log_message "Installation completed but some services are not running properly"
            log_message "Please check the logs and try redeploying the failed services"
            exit 1
        fi
    fi
fi