import React, { useState, useContext, useEffect } from 'react';
import { useDispatch, useSelector } from 'react-redux';
import { useMediaQuery } from 'react-responsive';
import * as Yup from 'yup';
import { snakeCase } from 'lodash/string';
import moment from 'moment';
import { getConfig, getPath } from '@edx/frontend-platform';

import type { Dispatch, AnyAction } from 'redux';
import type { TypeOfShape } from 'yup/lib/object';
import { RequestStatus } from './data/constants';
import { getCourseAppSettingValue, getLoadingStatus } from './pages-and-resources/data/selectors';
import { fetchCourseAppSettings, updateCourseAppSetting } from './pages-and-resources/data/thunks';
import { PagesAndResourcesContext } from './pages-and-resources/PagesAndResourcesProvider';
import {
  hasValidDateFormat, hasValidTimeFormat, decodeDateTime, endOfDayTime, startOfDayTime,
} from './pages-and-resources/discussions/app-config-form/utils';
import { DATE_TIME_FORMAT } from './constants';

export const executeThunk = async (
  thunk: (dispatch: any, state?: any) => Promise<any>,
  dispatch: Dispatch<AnyAction>,
  getState?: any,
) => {
  await thunk(dispatch, getState);
  await new Promise(setImmediate);
};

export function useIsMobile() {
  return useMediaQuery({ query: '(max-width: 767.98px)' });
}

export function useIsDesktop() {
  return useMediaQuery({ query: '(min-width: 992px)' });
}

export function convertObjectToSnakeCase(obj: Object, unpacked = false) {
  return Object.keys(obj).reduce((snakeCaseObj, key) => {
    const snakeCaseKey = snakeCase(key);
    const value = unpacked ? obj[key] : { value: obj[key] };
    return {
      ...snakeCaseObj,
      [snakeCaseKey]: value,
    };
  }, {});
}

export function deepConvertingKeysToCamelCase(obj: any[] | Object | null) {
  if (typeof obj !== 'object' || obj === null) {
    return obj;
  }

  if (Array.isArray(obj)) {
    return obj.map((item) => deepConvertingKeysToCamelCase(item));
  }

  const camelCaseObj = {};
  Object.keys(obj).forEach((key) => {
    const camelCaseKey = key.replace(/_([a-z])/g, (_, p1) => p1.toUpperCase());
    camelCaseObj[camelCaseKey] = deepConvertingKeysToCamelCase(obj[key]);
  });
  return camelCaseObj;
}

export function deepConvertingKeysToSnakeCase(obj: any[] | Object | null) {
  if (typeof obj !== 'object' || obj === null) {
    return obj;
  }

  if (Array.isArray(obj)) {
    return obj.map((item) => deepConvertingKeysToSnakeCase(item));
  }

  const snakeCaseObj = {};
  Object.entries(obj).forEach(([key, value]) => {
    const snakeCaseKey = key.replace(/([a-z])([A-Z])/g, '$1_$2').toLowerCase();
    snakeCaseObj[snakeCaseKey] = key === 'gradeCutoffs' ? value : deepConvertingKeysToSnakeCase(value);
  });
  return snakeCaseObj;
}

export function transformKeysToCamelCase(obj: { key: any; }) {
  return obj.key.replace(/_([a-z])/g, (_: any, letter: string) => letter.toUpperCase());
}

export function parseArrayOrObjectValues(obj: { [s: string]: string; } | ArrayLike<string>) {
  const result = {};

  Object.entries(obj).forEach(([key, value]) => {
    try {
      if (!Number.isNaN(Number(value))) {
        result[key] = value;
      } else {
        result[key] = JSON.parse(value);
      }
    } catch {
      result[key] = value;
    }
  });

  return result;
}

/**
 * Create a correct inner path depend on config PUBLIC_PATH.
 */
export const createCorrectInternalRoute = (checkPath: string): string => {
  let basePath = getPath(getConfig().PUBLIC_PATH);

  if (basePath.endsWith('/')) {
    basePath = basePath.slice(0, -1);
  }

  if (!checkPath?.startsWith(basePath)) {
    return `${basePath}${checkPath}`;
  }

  return checkPath;
};

export function getPagePath(courseId: string | undefined, isMfePageEnabled: string, urlParameter: string) {
  if (isMfePageEnabled === 'true') {
    if (urlParameter === 'tabs') {
      return `/course/${courseId}/pages-and-resources`;
    }
    return `/course/${courseId}/${urlParameter}`;
  }
  return `${getConfig().STUDIO_BASE_URL}/${urlParameter}/${courseId}`;
}

export function useAppSetting(settingName: string) {
  const dispatch = useDispatch();
  const { courseId } = useContext(PagesAndResourcesContext);
  const settingValue = useSelector(getCourseAppSettingValue(settingName));
  const loadingStatus = useSelector(getLoadingStatus);
  useEffect(() => {
    if ([RequestStatus.DENIED, RequestStatus.FAILED].includes(loadingStatus)) {
      return;
    }
    if (settingValue === undefined || settingValue === null) {
      dispatch(fetchCourseAppSettings(courseId, [settingName]));
    }
  }, [courseId]);

  const saveSetting = async (value: any) => dispatch(updateCourseAppSetting(courseId, settingName, value));
  return [settingValue, saveSetting];
}

export const getLabelById = (options: any[], id: any) => {
  const foundOption = options.find((option) => option.id === id);
  return foundOption ? foundOption.label : '';
};

interface YupTestContextExtended {
  originalValue?: unknown;
}

/**
 * Adds additional validation methods to Yup.
 */
export function setupYupExtensions() {
  // Add a uniqueProperty method to arrays that allows validating that the specified property path is unique
  // across all objects in the array.
  // Credit: https://github.com/jquense/yup/issues/345#issuecomment-717400071
  Yup.addMethod(Yup.array, 'uniqueProperty', function uniqueProperty(property, message) {
    return this.test('unique', '', function testUniqueness(list) {
      const errors: Yup.ValidationError[] = [];

      list?.forEach((item, index) => {
        const propertyValue = item[property];

        if (propertyValue && list.filter(entry => entry[property] === propertyValue).length > 1) {
          errors.push(
            this.createError({
              path: `${this.path}[${index}].${property}`,
              message,
            }),
          );
        }
      });

      if (errors.length > 0) {
        throw new Yup.ValidationError(errors);
      }

      return true;
    });
  });

  Yup.addMethod(Yup.object, 'uniqueObjectProperty', function uniqueObjectProperty(propertyName, message) {
    return this.test('unique', message, function testUniqueness(discussionTopic) {
      if (!discussionTopic || !discussionTopic[propertyName]) {
        return true;
      }
      const isDuplicate = this.parent.filter((topic: TypeOfShape<any>) => topic !== discussionTopic)
        .some((
          topic: { [x: string]: string; },
        ) => topic[propertyName]?.toLowerCase() === discussionTopic[propertyName].toLowerCase());

      if (isDuplicate) {
        throw this.createError({
          path: `${this.path}.${propertyName}`,
          message,
        });
      }
      return true;
    });
  });

  Yup.addMethod(Yup.string, 'compare', function compare(message, type) {
    return this.test('isGreater', message, function isGreater() {
      // This function compare 2 dates or 2 times. It return no error if dateInstance/timeInstance is empty
      // of if startTime or endTime is not present for time comparison
      // or startDate or endDate is not present for date comparison

      if (!this.parent
        || (!(this.parent.startTime && this.parent.endTime) && type === 'time')
        || (!(this.parent.startDate && this.parent.endDate) && type === 'date')
      ) {
        return true;
      }

      const startDateTime = decodeDateTime(this.parent.startDate, startOfDayTime(this.parent.startTime));
      const endDateTime = decodeDateTime(this.parent.endDate, endOfDayTime(this.parent.endTime));
      let isInvalidStartDateTime: boolean = false;

      if (type === 'date') {
        isInvalidStartDateTime = startDateTime.isAfter(endDateTime);
      } else if (type === 'time') {
        isInvalidStartDateTime = startDateTime.isSameOrAfter(endDateTime);
      }

      if (isInvalidStartDateTime) {
        throw this.createError({
          path: `${this.path}`,
          message,
        });
      }
      return true;
    });
  });

  Yup.addMethod(Yup.string, 'checkFormat', function checkFormat(message, type) {
    return this.test('isValidFormat', message, function isValidFormat() {
      const { originalValue } = this as Yup.TestContext & YupTestContextExtended;
      if (!originalValue) {
        return true;
      }
      let isValid: boolean = false;

      if (type === 'date') {
        isValid = hasValidDateFormat(originalValue);
      } else if (type === 'time') {
        isValid = hasValidTimeFormat(originalValue);
      }

      if (!isValid) {
        throw this.createError({
          path: `${this.path}`,
          message,
        });
      }
      return true;
    });
  });
}

export const convertToDateFromString = (dateStr: string): Date | undefined => {
  /**
   * Convert UTC to local time for react-datepicker
   * Note: react-datepicker v4 had a bug where it only interacts with local time
   * but this bug may no longer be affecting v8+ ?
   * @param {string} dateStr - YYYY-MM-DDTHH:MM:SSZ
   * @return date in local time
   */
  if (!dateStr) {
    return undefined;
  }

  const stripTimeZone = (stringValue: string) => stringValue.substring(0, 19);

  return moment(stripTimeZone(String(dateStr))).toDate();
};

export const convertToStringFromDate = (date: moment.MomentInput): string => {
  /**
   * Convert local time to UTC from react-datepicker
   * Note: react-datepicker v4 had a bug where it only interacts with local time
   * but this bug may no longer be affecting v8+ ?
   * @param {Date} date - date in local time
   * @return YYYY-MM-DDTHH:MM:SSZ
   */
  if (!date) {
    return '';
  }

  return moment(date).format(DATE_TIME_FORMAT);
};

export const isValidDate = (date: moment.MomentInput) => {
  const formattedValue = convertToStringFromDate(date).split('T')[0];

  return Boolean(formattedValue.length <= 10);
};

export const getFileSizeToClosestByte = (fileSize: any) => {
  let divides = 0;
  let size = fileSize;
  while (size > 1000 && divides < 4) {
    size /= 1000;
    divides += 1;
  }
  const units = ['B', 'KB', 'MB', 'GB', 'TB'];
  const fileSizeFixedDecimal = Number.parseFloat(size).toFixed(2);
  return `${fileSizeFixedDecimal} ${units[divides]}`;
};

/**
* A generic hook to run callback on next render cycle.
* @param {} callback - Callback function that needs to be run later
*/
export const useRunOnNextRender = (callback: () => void) => {
  const [scheduled, setScheduled] = useState(false);

  useEffect(() => {
    if (!scheduled) {
      return;
    }

    setScheduled(false);
    callback();
  }, [scheduled]);

  return () => setScheduled(true);
};

/**
 * Checks if the click event originated from an element with the stop-event-propagation class.
 * If so, return without further processing.
 */
export const skipIfUnwantedTarget = (
  e: React.MouseEvent,
  onClick: (e: React.MouseEvent) => void,
  selector?: string,
) => {
  const target = e.target as HTMLElement;
  if (target && target.closest(selector || '.stop-event-propagation')) {
    return;
  }
  onClick(e);
};

export const BoldText = (chunk: string[]) => <b>{chunk}</b>;
export const Div = (chunk: string[]) => <div>{chunk}</div>;
export const Paragraph = (chunk: string[]) => <p>{chunk}</p>;