#!/bin/bash

# Common functions and utilities for bootc image creation modules
# This module provides shared functionality used across all other modules

set -e

# Colors for 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 "${GREEN}[INFO]${NC} $1"
}

log_warn() {
    echo -e "${YELLOW}[WARN]${NC} $1"
}

log_error() {
    echo -e "${RED}[ERROR]${NC} $1"
}

log_debug() {
    echo -e "${BLUE}[DEBUG]${NC} $1"
}

# Global variables (will be set by calling script)
WORK_DIR=""
loop_dev=""

# Cleanup function
cleanup() {
    if [ -n "$WORK_DIR" ] && [ -d "$WORK_DIR" ]; then
        log_info "Cleaning up work directory..."
        sudo umount "$WORK_DIR/mnt" 2>/dev/null || true
        sudo losetup -d "$loop_dev" 2>/dev/null || true
        sudo rm -rf "$WORK_DIR"
    fi
}

# Set trap for cleanup
setup_cleanup() {
    trap cleanup EXIT INT TERM
}

# Check prerequisites
check_prerequisites() {
    log_info "Checking prerequisites..."
    
    local required_commands=("podman" "qemu-img" "parted" "losetup" "mkfs.ext4" "grub-install" "grub-mkconfig")
    
    for cmd in "${required_commands[@]}"; do
        if ! command -v "$cmd" >/dev/null 2>&1; then
            log_error "Required command '$cmd' not found"
            exit 1
        fi
    done
    
    # Check if container image exists
    if ! podman image exists "$CONTAINER_IMAGE"; then
        log_error "Container image '$CONTAINER_IMAGE' not found"
        log_info "Please build the image first with: podman build -t $CONTAINER_IMAGE -f debian_bootc_dockerfile.txt ."
        exit 1
    fi
    
    log_info "All prerequisites satisfied"
}

# Create output directory
create_output_dir() {
    log_info "Creating output directory..."
    mkdir -p "$OUTPUT_DIR"
}

# Create work directory
create_work_dir() {
    WORK_DIR="./work-$$"
    log_info "Creating work directory: $WORK_DIR"
    mkdir -p "$WORK_DIR"
}

# Validate configuration
validate_config() {
    if [ -z "$CONTAINER_IMAGE" ]; then
        log_error "CONTAINER_IMAGE not set"
        exit 1
    fi
    
    if [ -z "$OUTPUT_DIR" ]; then
        log_error "OUTPUT_DIR not set"
        exit 1
    fi
    
    if [ -z "$IMAGE_SIZE_GB" ]; then
        log_error "IMAGE_SIZE_GB not set"
        exit 1
    fi
    
    log_debug "Configuration validated successfully"
}

# Show progress
show_progress() {
    local step="$1"
    local total="$2"
    local current="$3"
    
    local percentage=$((current * 100 / total))
    local bar_length=30
    local filled=$((bar_length * current / total))
    local empty=$((bar_length - filled))
    
    printf "\r["
    printf "%${filled}s" | tr ' ' '#'
    printf "%${empty}s" | tr ' ' '-'
    printf "] %d%% - %s" "$percentage" "$step"
    
    if [ "$current" -eq "$total" ]; then
        echo
    fi
}

# Check disk space
check_disk_space() {
    # Get the directory where the main script is located
    local script_dir="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
    local required_space=$((IMAGE_SIZE_GB * 1024 * 1024 * 1024))  # Convert GB to bytes
    local available_space=$(df "$script_dir" | awk 'NR==2 {print $4}')
    
    # Convert available space to GB for comparison
    local available_gb=$((available_space / 1024 / 1024 / 1024))
    
    log_debug "Disk space check: Required: ${IMAGE_SIZE_GB}GB, Available: ${available_gb}GB"
    
    if [ "$available_gb" -lt "$IMAGE_SIZE_GB" ]; then
        log_error "Insufficient disk space. Required: ${IMAGE_SIZE_GB}GB, Available: ${available_gb}GB"
        exit 1
    fi
    
    log_debug "Disk space check passed"
}

# Wait for user confirmation
confirm_action() {
    local message="$1"
    local default="${2:-n}"
    
    if [ "$default" = "y" ]; then
        read -p "$message [Y/n]: " -r
        if [[ $REPLY =~ ^[Nn]$ ]]; then
            return 1
        fi
    else
        read -p "$message [y/N]: " -r
        if [[ ! $REPLY =~ ^[Yy]$ ]]; then
            return 1
        fi
    fi
    
    return 0
}

# Print module usage
print_module_usage() {
    local module_name="$1"
    echo "Usage: source modules/$module_name.sh"
    echo "This module provides common functionality for bootc image creation."
    echo ""
    echo "Available functions:"
    echo "  log_info, log_warn, log_error, log_debug - Logging functions"
    echo "  cleanup, setup_cleanup - Cleanup management"
    echo "  check_prerequisites - Validate system requirements"
    echo "  create_output_dir, create_work_dir - Directory management"
    echo "  validate_config - Configuration validation"
    echo "  show_progress - Progress display"
    echo "  check_disk_space - Disk space validation"
    echo "  confirm_action - User confirmation prompts"
}