#!/bin/bash
#
# Common Library Functions for Deployment Scripts
# Provides unified logging, error handling, and utilities
#

set -euo pipefail

# Colors for output
readonly RED='\033[0;31m'
readonly GREEN='\033[0;32m'
readonly YELLOW='\033[1;33m'
readonly BLUE='\033[0;34m'
readonly CYAN='\033[0;36m'
readonly MAGENTA='\033[0;35m'
readonly NC='\033[0m' # No Color

# Logging functions
log_info() {
    echo -e "${BLUE}ℹ️  ${1}${NC}"
}

log_success() {
    echo -e "${GREEN}✅ ${1}${NC}"
}

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

log_error() {
    echo -e "${RED}❌ ${1}${NC}"
}

log_debug() {
    if [[ "${DEBUG:-0}" == "1" ]]; then
        echo -e "${CYAN}🔍 ${1}${NC}"
    fi
}

log_step() {
    echo -e "${MAGENTA}▶️  ${1}${NC}"
}

# Error handling
die() {
    log_error "$1"
    exit "${2:-1}"
}

# Check if command exists
command_exists() {
    command -v "$1" &> /dev/null
}

# Validate prerequisites
require_command() {
    local cmd="$1"
    local install_hint="${2:-}"

    if ! command_exists "$cmd"; then
        log_error "Required command not found: $cmd"
        [[ -n "$install_hint" ]] && log_info "Install with: $install_hint"
        return 1
    fi
    return 0
}

# Run command with retry logic
run_with_retry() {
    local max_attempts="${1}"
    local delay="${2}"
    shift 2
    local cmd=("$@")
    local attempt=1

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

        if [[ $attempt -lt $max_attempts ]]; then
            log_warning "Command failed (attempt $attempt/$max_attempts). Retrying in ${delay}s..."
            sleep "$delay"
        fi

        ((attempt++))
    done

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

# Execute command and capture output
execute() {
    local cmd="$1"
    log_debug "Executing: $cmd"
    eval "$cmd"
}

# Spinner for long-running operations
spinner() {
    local pid=$1
    local delay=0.1
    local spinstr='⠋⠙⠹⠸⠼⠴⠦⠧⠇⠏'

    while ps -p "$pid" > /dev/null 2>&1; do
        local temp=${spinstr#?}
        printf " [%c]  " "$spinstr"
        local spinstr=$temp${spinstr%"$temp"}
        sleep $delay
        printf "\b\b\b\b\b\b"
    done
    printf "    \b\b\b\b"
}

# Progress bar
progress_bar() {
    local current=$1
    local total=$2
    local width=50
    local percentage=$((current * 100 / total))
    local completed=$((width * current / total))
    local remaining=$((width - completed))

    printf "\r["
    printf "%${completed}s" | tr ' ' '█'
    printf "%${remaining}s" | tr ' ' '░'
    printf "] %3d%%" "$percentage"

    if [[ $current -eq $total ]]; then
        echo ""
    fi
}

# Confirm action
confirm() {
    local prompt="${1:-Are you sure?}"
    local default="${2:-n}"

    if [[ "$default" == "y" ]]; then
        prompt="$prompt [Y/n] "
    else
        prompt="$prompt [y/N] "
    fi

    read -rp "$prompt" response
    response=${response:-$default}

    [[ "$response" =~ ^[Yy]$ ]]
}

# Parse YAML-like config
parse_config() {
    local config_file="$1"
    local key="$2"

    if [[ ! -f "$config_file" ]]; then
        log_error "Config file not found: $config_file"
        return 1
    fi

    grep "^${key}:" "$config_file" | sed "s/^${key}:[[:space:]]*//" | tr -d '"'
}

# Timestamp functions
timestamp() {
    date '+%Y-%m-%d %H:%M:%S'
}

timestamp_file() {
    date '+%Y%m%d_%H%M%S'
}

# Duration calculation
duration() {
    local start=$1
    local end=${2:-$(date +%s)}
    local elapsed=$((end - start))

    local hours=$((elapsed / 3600))
    local minutes=$(((elapsed % 3600) / 60))
    local seconds=$((elapsed % 60))

    if [[ $hours -gt 0 ]]; then
        printf "%dh %dm %ds" "$hours" "$minutes" "$seconds"
    elif [[ $minutes -gt 0 ]]; then
        printf "%dm %ds" "$minutes" "$seconds"
    else
        printf "%ds" "$seconds"
    fi
}

# Cleanup handler
cleanup_handlers=()

register_cleanup() {
    cleanup_handlers+=("$1")
}

cleanup() {
    log_info "Running cleanup handlers..."
    for handler in "${cleanup_handlers[@]}"; do
        eval "$handler" || log_warning "Cleanup handler failed: $handler"
    done
}

trap cleanup EXIT

# Export functions for use in other scripts
export -f log_info log_success log_warning log_error log_debug log_step
export -f die command_exists require_command run_with_retry execute
export -f spinner progress_bar confirm parse_config
export -f timestamp timestamp_file duration
export -f register_cleanup cleanup