/**
 * This file is part of the NocoBase (R) project.
 * Copyright (c) 2020-2024 NocoBase Co., Ltd.
 * Authors: NocoBase Team.
 *
 * This project is dual-licensed under AGPL-3.0 and NocoBase Commercial License.
 * For more information, please refer to: https://www.nocobase.com/agreement.
 */

import { FlowEngineContext } from '../flowContext';
import { define, observable } from '../reactive';
import { encodeOpenViewRouteState, ViewParam as SharedViewParam } from '../utils';

type ViewParams = Omit<SharedViewParam, 'viewUid'> & { viewUid?: string };

export interface GeneratePathnameFromViewParamsOptions {
  prefix?: string;
  basePath?: string;
}

export interface ViewNavigationOptions {
  basePath?: string;
  layoutBasePath?: string;
}

function encodeFilterByTk(val: SharedViewParam['filterByTk']): string {
  if (val === undefined || val === null) return '';
  // 1.x 兼容：对象按 key1=v1&key2=v2 拼接后整体 encodeURIComponent
  if (val && typeof val === 'object' && !Array.isArray(val)) {
    const pairs = Object.entries(val).map(([k, v]) => {
      return `${encodeURIComponent(String(k))}=${encodeURIComponent(String(v))}`;
    });
    return encodeURIComponent(pairs.join('&'));
  }
  // 其它情况按原单值编码（字符串）
  return encodeURIComponent(String(val));
}

function hasUsableSourceId(sourceId: unknown): sourceId is string | number {
  return sourceId !== undefined && sourceId !== null && String(sourceId) !== '';
}

function normalizeBasePath(basePath?: string) {
  const value = basePath || '/admin';
  return `/${value.replace(/^\/+/, '').replace(/\/+$/, '')}`;
}

/**
 * 将 ViewParam 数组转换为 pathname
 *
 * @param viewParams - ViewParam 数组
 * @returns 生成的 pathname
 *
 * @example
 * ```typescript
 * generatePathnameFromViewParams([{ viewUid: 'xxx' }]) // '/admin/xxx'
 * generatePathnameFromViewParams([{ viewUid: 'xxx', tabUid: 'yyy' }]) // '/admin/xxx/tab/yyy'
 * generatePathnameFromViewParams([{ viewUid: 'xxx' }, { viewUid: 'yyy' }]) // '/admin/xxx/view/yyy'
 * ```
 */
export function generatePathnameFromViewParams(
  viewParams: ViewParams[],
  options: GeneratePathnameFromViewParamsOptions = {},
): string {
  const basePath = normalizeBasePath(options.basePath || options.prefix);

  if (!viewParams || viewParams.length === 0) {
    return basePath;
  }

  const segments = basePath.replace(/^\/+/, '').split('/').filter(Boolean);

  viewParams.forEach((viewParam, index) => {
    // 如果不是第一个视图，添加 'view' 关键字
    if (index > 0) {
      segments.push('view');
    }

    // 添加视图 UID
    segments.push(viewParam.viewUid);

    const openViewRouteStateToken = encodeOpenViewRouteState(viewParam.viewUid, viewParam.openViewRouteState);
    if (openViewRouteStateToken) {
      segments.push('opts', openViewRouteStateToken);
    }

    // 添加参数
    if (viewParam.tabUid) {
      segments.push('tab', viewParam.tabUid);
    }
    if (viewParam.filterByTk != null) {
      const encoded = encodeFilterByTk(viewParam.filterByTk);
      if (encoded) {
        segments.push('filterbytk', encoded);
      }
    }
    if (hasUsableSourceId(viewParam.sourceId)) {
      segments.push('sourceid', String(viewParam.sourceId));
    }
  });

  return '/' + segments.join('/');
}

export class ViewNavigation {
  viewStack: ReadonlyArray<ViewParams>; // 只能通过 setViewStack 修改
  ctx: FlowEngineContext;
  viewParams: ViewParams;
  private readonly basePath?: string;

  constructor(ctx: FlowEngineContext, viewParams: ViewParams[], options: ViewNavigationOptions = {}) {
    this.setViewStack(viewParams);
    this.ctx = ctx;
    this.basePath = options.basePath || options.layoutBasePath;

    define(this, {
      viewParams: observable,
    });
  }

  setViewStack(viewParams: ViewParams[]) {
    this.viewStack = Object.freeze([...viewParams]);
    this.viewParams = this.viewStack[this.viewStack.length - 1] || {};
  }

  changeTo(viewParam: ViewParams) {
    // 1. 根据传入的参数，合并成新的 viewStack
    const newViewStack = this.viewStack.map((item, index) => {
      if (index === this.viewStack.length - 1) {
        return { ...item, ...viewParam };
      }
      return { ...item };
    });

    // 2. 根据 viewStack 生成新的 pathname
    const newPathname = generatePathnameFromViewParams(newViewStack, { basePath: this.getLayoutBasePath() });

    // 3. 触发一次跳转。使用 replace 的方式
    this.ctx.router.navigate(newPathname, { replace: true });
  }

  navigateTo(viewParam: ViewParams, opts?: { replace?: boolean; state?: any }) {
    // 1. 基于当前 viewStack 生成一个 pathname
    // 2. 将当前传入的参数转为 path string
    const newViewPathname = generatePathnameFromViewParams([...this.viewStack, viewParam], {
      basePath: this.getLayoutBasePath(),
    });

    // 3. 与 pathname 拼接成新的 pathname（这里直接使用新生成的 pathname）
    const newPathname = newViewPathname;

    // 4. 如果新的 pathname 与当前 ctx.route.pathname 不同，则触发一次跳转。使用 push 的方式
    this.ctx.router.navigate(newPathname, opts);
  }

  back() {
    const prevStack = this.viewStack.slice(0, -1);
    const prevPath = generatePathnameFromViewParams(prevStack, { basePath: this.getLayoutBasePath() });
    this.ctx.router.navigate(prevPath, { replace: true });
  }

  private getLayoutBasePath() {
    const routePath = (this.ctx as any).layout?.routePath;
    return (
      this.basePath ||
      (this.ctx as any).layoutRoute?.basePathname ||
      (routePath?.startsWith('/') ? routePath : '/admin')
    );
  }
}