/**
 * 컴포넌트 설정 공통 스키마 및 병합 유틸리티
 * 
 * 모든 컴포넌트가 공통으로 사용
 * - 기본값: 각 컴포넌트의 defaultConfig에서 가져옴
 * - 커스텀: DB custom_config에서 가져옴
 * - 최종 설정 = 기본값 + 커스텀 (깊은 병합)
 */
import { z } from "zod";

// ============================================
// 공통 스키마 (모든 구조 허용)
// ============================================
export const customConfigSchema = z.record(z.any());

export type CustomConfig = z.infer<typeof customConfigSchema>;

// ============================================
// 깊은 병합 함수
// ============================================
export function deepMerge<T extends Record<string, any>>(
  target: T,
  source: Record<string, any>
): T {
  const result = { ...target };
  
  for (const key of Object.keys(source)) {
    const sourceValue = source[key];
    const targetValue = result[key as keyof T];
    
    // 둘 다 객체이고 배열이 아니면 깊은 병합
    if (
      isPlainObject(sourceValue) &&
      isPlainObject(targetValue)
    ) {
      result[key as keyof T] = deepMerge(targetValue, sourceValue);
    } else if (sourceValue !== undefined) {
      // source 값이 있으면 덮어쓰기
      result[key as keyof T] = sourceValue;
    }
  }
  
  return result;
}

function isPlainObject(value: unknown): value is Record<string, any> {
  return (
    typeof value === "object" &&
    value !== null &&
    !Array.isArray(value) &&
    Object.prototype.toString.call(value) === "[object Object]"
  );
}

// ============================================
// 설정 병합 함수 (렌더링 시 사용)
// ============================================
export function mergeComponentConfig(
  defaultConfig: Record<string, any>,
  customConfig: Record<string, any> | null | undefined
): Record<string, any> {
  if (!customConfig || Object.keys(customConfig).length === 0) {
    return { ...defaultConfig };
  }
  
  return deepMerge(defaultConfig, customConfig);
}

// ============================================
// 커스텀 설정 추출 함수 (저장 시 사용)
// ============================================
export function extractCustomConfig(
  fullConfig: Record<string, any>,
  defaultConfig: Record<string, any>
): Record<string, any> {
  const customConfig: Record<string, any> = {};
  
  for (const key of Object.keys(fullConfig)) {
    const fullValue = fullConfig[key];
    const defaultValue = defaultConfig[key];
    
    // 기본값과 다른 경우만 커스텀으로 추출
    if (!isDeepEqual(fullValue, defaultValue)) {
      customConfig[key] = fullValue;
    }
  }
  
  return customConfig;
}

// ============================================
// 깊은 비교 함수
// ============================================
export function isDeepEqual(a: unknown, b: unknown): boolean {
  if (a === b) return true;
  if (a == null || b == null) return a === b;
  if (typeof a !== typeof b) return false;
  if (typeof a !== "object") return a === b;
  
  if (Array.isArray(a) !== Array.isArray(b)) return false;
  if (Array.isArray(a) && Array.isArray(b)) {
    if (a.length !== b.length) return false;
    for (let i = 0; i < a.length; i++) {
      if (!isDeepEqual(a[i], b[i])) return false;
    }
    return true;
  }
  
  const objA = a as Record<string, unknown>;
  const objB = b as Record<string, unknown>;
  const keysA = Object.keys(objA);
  const keysB = Object.keys(objB);
  
  if (keysA.length !== keysB.length) return false;
  
  for (const key of keysA) {
    if (!keysB.includes(key)) return false;
    if (!isDeepEqual(objA[key], objB[key])) return false;
  }
  
  return true;
}

// ============================================
// 컴포넌트 URL 생성 함수
// ============================================
export function getComponentUrl(componentType: string): string {
  return `@/lib/registry/components/${componentType}`;
}

// ============================================
// 컴포넌트 타입 추출 함수 (URL에서)
// ============================================
export function getComponentTypeFromUrl(componentUrl: string): string {
  // "@/lib/registry/components/split-panel-layout" → "split-panel-layout"
  const parts = componentUrl.split("/");
  return parts[parts.length - 1];
}

// ============================================
// V2 레이아웃 스키마
// ============================================
export const componentV2Schema = z.object({
  id: z.string(),
  url: z.string(),
  position: z.object({
    x: z.number().default(0),
    y: z.number().default(0),
  }),
  size: z.object({
    width: z.number().default(100),
    height: z.number().default(100),
  }),
  displayOrder: z.number().default(0),
  overrides: z.record(z.any()).default({}),
});

export const layoutV2Schema = z.object({
  version: z.string().default("2.0"),
  components: z.array(componentV2Schema).default([]),
  updatedAt: z.string().optional(),
});

export type ComponentV2 = z.infer<typeof componentV2Schema>;
export type LayoutV2 = z.infer<typeof layoutV2Schema>;

// ============================================
// 컴포넌트별 기본값 레지스트리
// ============================================
const componentDefaultsRegistry: Record<string, Record<string, any>> = {
  "table-list": {
    pagination: true,
    pageSize: 20,
    selectable: true,
    showHeader: true,
  },
  "button-primary": {
    label: "버튼",
    variant: "default",
    size: "default",
  },
  "text-input": {
    placeholder: "",
    multiline: false,
  },
  "select-basic": {
    placeholder: "선택하세요",
    options: [],
  },
  "date-input": {
    format: "YYYY-MM-DD",
  },
  "split-panel-layout": {
    splitRatio: 50,
    direction: "horizontal",
    resizable: true,
  },
  "tabs-widget": {
    tabs: [],
    defaultTab: 0,
  },
  "card-display": {
    title: "",
    bordered: true,
  },
  "flow-widget": {
    flowId: null,
  },
  "category-management": {
    categoryType: "",
  },
  "pivot-table": {
    rows: [],
    columns: [],
    values: [],
  },
  "unified-grid": {
    columns: [],
  },
  "checkbox-basic": {
    label: "",
    defaultChecked: false,
  },
  "radio-basic": {
    options: [],
  },
  "file-upload": {
    accept: "*",
    multiple: false,
  },
  "repeat-container": {
    children: [],
  },
};

// ============================================
// 컴포넌트 기본값 조회
// ============================================
export function getComponentDefaults(componentType: string): Record<string, any> {
  return componentDefaultsRegistry[componentType] || {};
}

// ============================================
// URL에서 기본값 조회
// ============================================
export function getDefaultsByUrl(url: string): Record<string, any> {
  const componentType = getComponentTypeFromUrl(url);
  return getComponentDefaults(componentType);
}

// ============================================
// V2 컴포넌트 로드 (기본값 + overrides 병합)
// ============================================
export function loadComponentV2(component: ComponentV2): ComponentV2 & { config: Record<string, any> } {
  const defaults = getDefaultsByUrl(component.url);
  const config = mergeComponentConfig(defaults, component.overrides);
  
  return {
    ...component,
    config,
  };
}

// ============================================
// V2 컴포넌트 저장 (차이값 추출)
// ============================================
export function saveComponentV2(
  component: ComponentV2 & { config?: Record<string, any> }
): ComponentV2 {
  const defaults = getDefaultsByUrl(component.url);
  const overrides = component.config 
    ? extractCustomConfig(component.config, defaults)
    : component.overrides;
  
  return {
    id: component.id,
    url: component.url,
    position: component.position,
    size: component.size,
    displayOrder: component.displayOrder,
    overrides,
  };
}

// ============================================
// V2 레이아웃 로드 (전체 컴포넌트 기본값 병합)
// ============================================
export function loadLayoutV2(layoutData: any): LayoutV2 & { components: Array<ComponentV2 & { config: Record<string, any> }> } {
  const parsed = layoutV2Schema.parse(layoutData || { version: "2.0", components: [] });
  
  return {
    ...parsed,
    components: parsed.components.map(loadComponentV2),
  };
}

// ============================================
// V2 레이아웃 저장 (전체 컴포넌트 차이값 추출)
// ============================================
export function saveLayoutV2(
  components: Array<ComponentV2 & { config?: Record<string, any> }>
): LayoutV2 {
  return {
    version: "2.0",
    components: components.map(saveComponentV2),
    updatedAt: new Date().toISOString(),
  };
}