#!/bin/bash
# Common utility functions for K3s deployment scripts

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

# Project directories
SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
PROJECT_DIR="$(dirname "$SCRIPT_DIR")"
STATE_FILE="$PROJECT_DIR/.deployment-state"
LOG_FILE="$PROJECT_DIR/deployment.log"

# Logging functions
log() {
    local message="$1"
    local timestamp=$(date '+%Y-%m-%d %H:%M:%S')
    echo -e "${GREEN}[INFO]${NC} $message"
    echo "[$timestamp] [INFO] $message" >> "$LOG_FILE"
}

log_error() {
    local message="$1"
    local timestamp=$(date '+%Y-%m-%d %H:%M:%S')
    echo -e "${RED}[ERROR]${NC} $message" >&2
    echo "[$timestamp] [ERROR] $message" >> "$LOG_FILE"
}

log_warn() {
    local message="$1"
    local timestamp=$(date '+%Y-%m-%d %H:%M:%S')
    echo -e "${YELLOW}[WARN]${NC} $message"
    echo "[$timestamp] [WARN] $message" >> "$LOG_FILE"
}

log_step() {
    local message="$1"
    local timestamp=$(date '+%Y-%m-%d %H:%M:%S')
    echo -e "${BLUE}[STEP]${NC} $message"
    echo "[$timestamp] [STEP] $message" >> "$LOG_FILE"
}

# State management functions
mark_step_completed() {
    local step_name="$1"
    echo "$step_name" >> "$STATE_FILE"
    log "✓ Marked step as completed: $step_name"
}

is_step_completed() {
    local step_name="$1"
    if [ ! -f "$STATE_FILE" ]; then
        return 1
    fi
    grep -q "^$step_name$" "$STATE_FILE" 2>/dev/null
}

reset_deployment_state() {
    if [ -f "$STATE_FILE" ]; then
        rm -f "$STATE_FILE"
        log "Deployment state reset"
    fi
}

# Tool checking functions
check_tool() {
    local tool_name="$1"
    local install_cmd="$2"

    if command -v "$tool_name" &> /dev/null; then
        log "✓ Tool available: $tool_name"
        return 0
    else
        log_warn "Tool not found: $tool_name"
        if [ -n "$install_cmd" ]; then
            log "Installing $tool_name..."
            if eval "$install_cmd"; then
                log "✓ Successfully installed: $tool_name"
                return 0
            else
                log_error "Failed to install: $tool_name"
                return 1
            fi
        else
            log_error "Please install $tool_name manually"
            return 1
        fi
    fi
}

check_required_tools() {
    local all_ok=true

    log_step "Checking required tools..."

    check_tool "python3" "sudo apt update && sudo apt install -y python3" || all_ok=false
    check_tool "ansible" "sudo apt update && sudo apt install -y ansible" || all_ok=false
    check_tool "git" "sudo apt update && sudo apt install -y git" || all_ok=false

    if [ "$all_ok" = false ]; then
        log_error "Some required tools are missing"
        return 1
    fi

    log "✓ All required tools are available"
    return 0
}

# Network checking functions
check_network() {
    local test_url="${1:-https://www.google.com}"
    local timeout="${2:-5}"

    if curl -s --max-time "$timeout" --head "$test_url" > /dev/null 2>&1; then
        return 0
    else
        return 1
    fi
}

check_network_with_retry() {
    local test_url="${1:-https://www.google.com}"
    local max_attempts="${2:-3}"
    local attempt=1

    while [ $attempt -le $max_attempts ]; do
        if check_network "$test_url"; then
            log "✓ Network connection OK"
            return 0
        fi
        log_warn "Network check failed (attempt $attempt/$max_attempts)"
        attempt=$((attempt + 1))
        sleep 2
    done

    log_error "Network connection failed after $max_attempts attempts"
    return 1
}

# Retry mechanism
retry() {
    local max_attempts="$1"
    local delay="$2"
    shift 2
    local cmd="$@"
    local attempt=1

    while [ $attempt -le $max_attempts ]; do
        if eval "$cmd"; then
            return 0
        fi

        if [ $attempt -lt $max_attempts ]; then
            log_warn "Command failed (attempt $attempt/$max_attempts), retrying in ${delay}s..."
            sleep "$delay"
        fi
        attempt=$((attempt + 1))
    done

    log_error "Command failed after $max_attempts attempts: $cmd"
    return 1
}

# Configuration file validation
check_config_file() {
    local config_file="${1:-$PROJECT_DIR/config/cluster-vars.yml}"

    if [ ! -f "$config_file" ]; then
        log_error "Configuration file not found: $config_file"
        log_error "Please copy config/cluster-vars.yml.example to config/cluster-vars.yml and configure it"
        return 1
    fi

    log "✓ Configuration file exists: $config_file"

    # Check if yq is available for validation
    if command -v yq &> /dev/null; then
        if yq eval '.' "$config_file" > /dev/null 2>&1; then
            log "✓ Configuration file is valid YAML"
        else
            log_error "Configuration file has invalid YAML syntax"
            return 1
        fi
    fi

    return 0
}

# Kubernetes cluster checking
check_kubectl() {
    if ! command -v kubectl &> /dev/null; then
        log_warn "kubectl not found, will be available after K3s installation"
        return 1
    fi

    if ! kubectl cluster-info &> /dev/null; then
        log_warn "kubectl cannot connect to cluster"
        return 1
    fi

    log "✓ kubectl is available and connected"
    return 0
}

wait_for_pods() {
    local namespace="$1"
    local label="$2"
    local timeout="${3:-600}"

    log "Waiting for pods in namespace $namespace with label $label..."

    if kubectl wait --for=condition=ready pod \
        -l "$label" \
        -n "$namespace" \
        --timeout="${timeout}s" 2>/dev/null; then
        log "✓ Pods are ready"
        return 0
    else
        log_error "Pods failed to become ready within ${timeout}s"
        return 1
    fi
}

wait_for_deployment() {
    local namespace="$1"
    local deployment="$2"
    local timeout="${3:-600}"

    log "Waiting for deployment $deployment in namespace $namespace..."

    if kubectl wait --for=condition=available \
        --timeout="${timeout}s" \
        deployment/"$deployment" \
        -n "$namespace" 2>/dev/null; then
        log "✓ Deployment is available"
        return 0
    else
        log_error "Deployment failed to become available within ${timeout}s"
        return 1
    fi
}

# Download with retry
download_file() {
    local url="$1"
    local output="$2"
    local max_attempts="${3:-3}"

    log "Downloading: $url"

    if retry "$max_attempts" 5 "curl -fsSL '$url' -o '$output'"; then
        log "✓ Downloaded successfully: $output"
        return 0
    else
        log_error "Failed to download: $url"
        return 1
    fi
}

# Install yq if not present
ensure_yq() {
    if command -v yq &> /dev/null; then
        log "✓ yq is already installed"
        return 0
    fi

    log "Installing yq..."
    local yq_url="https://github.com/mikefarah/yq/releases/latest/download/yq_linux_amd64"
    local yq_path="/usr/local/bin/yq"

    if download_file "$yq_url" "/tmp/yq" 3; then
        sudo mv /tmp/yq "$yq_path"
        sudo chmod +x "$yq_path"
        log "✓ yq installed successfully"
        return 0
    else
        log_error "Failed to install yq"
        return 1
    fi
}

# Install htpasswd if not present
ensure_htpasswd() {
    if command -v htpasswd &> /dev/null; then
        log "✓ htpasswd is already installed"
        return 0
    fi

    log "Installing htpasswd (apache2-utils)..."
    if sudo apt update && sudo apt install -y apache2-utils; then
        log "✓ htpasswd installed successfully"
        return 0
    else
        log_error "Failed to install htpasswd"
        return 1
    fi
}

# Install helm if not present
ensure_helm() {
    if command -v helm &> /dev/null; then
        log "✓ Helm is already installed"
        return 0
    fi

    log "Installing Helm..."
    if retry 3 5 "curl -fsSL https://raw.githubusercontent.com/helm/helm/main/scripts/get-helm-3 | bash"; then
        log "✓ Helm installed successfully"
        return 0
    else
        log_error "Failed to install Helm"
        return 1
    fi
}

# Cleanup function for temporary files
cleanup_temp_files() {
    local temp_dir="$1"
    if [ -n "$temp_dir" ] && [ -d "$temp_dir" ]; then
        rm -rf "$temp_dir"
        log "Cleaned up temporary directory: $temp_dir"
    fi
}

# Trap for cleanup on exit
setup_cleanup_trap() {
    local temp_dir="$1"
    trap "cleanup_temp_files '$temp_dir'" EXIT INT TERM
}

# Print summary
print_summary() {
    echo ""
    echo "=========================================="
    echo "  Deployment Summary"
    echo "=========================================="
    echo ""
}

# Export functions for use in other scripts
export -f log log_error log_warn log_step
export -f mark_step_completed is_step_completed reset_deployment_state
export -f check_tool check_required_tools
export -f check_network check_network_with_retry
export -f retry
export -f check_config_file check_kubectl
export -f wait_for_pods wait_for_deployment
export -f download_file
export -f ensure_yq ensure_htpasswd ensure_helm
export -f cleanup_temp_files setup_cleanup_trap
export -f print_summary