/**
 * @license
 * Copyright 2019 Google Inc.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */

import { MDCFoundation } from "@material/base/foundation";
import { MDCDataTableAdapter } from "./adapter";
import { cssClasses, strings } from "./constants";

export class MDCDataTableFoundation extends MDCFoundation<MDCDataTableAdapter> {
  static get defaultAdapter(): MDCDataTableAdapter {
    return {
      addClassAtRowIndex: () => undefined,
      getRowCount: () => 0,
      getRowElements: () => [],
      getRowIdAtIndex: () => "",
      getRowIndexByChildElement: () => 0,
      getSelectedRowCount: () => 0,
      isCheckboxAtRowIndexChecked: () => false,
      isHeaderRowCheckboxChecked: () => false,
      isRowsSelectable: () => false,
      notifyRowSelectionChanged: () => undefined,
      notifySelectedAll: () => undefined,
      notifyUnselectedAll: () => undefined,
      registerHeaderRowCheckbox: () => undefined,
      registerRowCheckboxes: () => undefined,
      removeClassAtRowIndex: () => undefined,
      setAttributeAtRowIndex: () => undefined,
      setHeaderRowCheckboxChecked: () => undefined,
      setHeaderRowCheckboxIndeterminate: () => undefined,
      setRowCheckboxCheckedAtIndex: () => undefined,
    };
  }

  constructor(adapter?: Partial<MDCDataTableAdapter>) {
    super({ ...MDCDataTableFoundation.defaultAdapter, ...adapter });
  }

  /**
   * Re-initializes header row checkbox and row checkboxes when selectable rows are added or removed from table.
   * Use this if registering checkbox is synchronous.
   */
  layout() {
    if (this.adapter_.isRowsSelectable()) {
      this.adapter_.registerHeaderRowCheckbox();
      this.adapter_.registerRowCheckboxes();

      this.setHeaderRowCheckboxState_();
    }
  }

  /**
   * Re-initializes header row checkbox and row checkboxes when selectable rows are added or removed from table.
   * Use this if registering checkbox is asynchronous.
   */
  async layoutAsync(): Promise<void> {
    if (this.adapter_.isRowsSelectable()) {
      await this.adapter_.registerHeaderRowCheckbox();
      await this.adapter_.registerRowCheckboxes();

      this.setHeaderRowCheckboxState_();
    }
  }

  /**
   * @return Returns array of row elements.
   */
  getRows(): Element[] {
    return this.adapter_.getRowElements();
  }

  /**
   * Sets selected row ids. Overwrites previously selected rows.
   * @param rowIds Array of row ids that needs to be selected.
   */
  setSelectedRowIds(rowIds: string[]) {
    for (let rowIndex = 0; rowIndex < this.adapter_.getRowCount(); rowIndex++) {
      const rowId = this.adapter_.getRowIdAtIndex(rowIndex);

      let isSelected = false;
      if (rowId && rowIds.indexOf(rowId) >= 0) {
        isSelected = true;
      }

      this.adapter_.setRowCheckboxCheckedAtIndex(rowIndex, isSelected);
      this.selectRowAtIndex_(rowIndex, isSelected);
    }

    this.setHeaderRowCheckboxState_();
  }

  /**
   * @return Returns array of selected row ids.
   */
  getSelectedRowIds(): Array<string | null> {
    const selectedRowIds: Array<string | null> = [];
    for (let rowIndex = 0; rowIndex < this.adapter_.getRowCount(); rowIndex++) {
      if (this.adapter_.isCheckboxAtRowIndexChecked(rowIndex)) {
        selectedRowIds.push(this.adapter_.getRowIdAtIndex(rowIndex));
      }
    }

    return selectedRowIds;
  }

  /**
   * Handles header row checkbox change event.
   */
  handleHeaderRowCheckboxChange() {
    const isHeaderChecked = this.adapter_.isHeaderRowCheckboxChecked();

    for (let rowIndex = 0; rowIndex < this.adapter_.getRowCount(); rowIndex++) {
      this.adapter_.setRowCheckboxCheckedAtIndex(rowIndex, isHeaderChecked);
      this.selectRowAtIndex_(rowIndex, isHeaderChecked);
    }

    if (isHeaderChecked) {
      this.adapter_.notifySelectedAll();
    } else {
      this.adapter_.notifyUnselectedAll();
    }
  }

  /**
   * Handles change event originated from row checkboxes.
   */
  handleRowCheckboxChange(event: Event) {
    const rowIndex = this.adapter_.getRowIndexByChildElement(
      event.target as HTMLInputElement
    );

    if (rowIndex === -1) {
      return;
    }

    const selected = this.adapter_.isCheckboxAtRowIndexChecked(rowIndex);

    this.selectRowAtIndex_(rowIndex, selected);
    this.setHeaderRowCheckboxState_();

    const rowId = this.adapter_.getRowIdAtIndex(rowIndex);
    this.adapter_.notifyRowSelectionChanged({ rowId, rowIndex, selected });
  }

  /**
   * Updates header row checkbox state based on number of rows selected.
   */
  private setHeaderRowCheckboxState_() {
    if (this.adapter_.getSelectedRowCount() === this.adapter_.getRowCount()) {
      this.adapter_.setHeaderRowCheckboxChecked(true);
      this.adapter_.setHeaderRowCheckboxIndeterminate(false);
    } else if (this.adapter_.getSelectedRowCount() === 0) {
      this.adapter_.setHeaderRowCheckboxIndeterminate(false);
      this.adapter_.setHeaderRowCheckboxChecked(false);
    } else {
      this.adapter_.setHeaderRowCheckboxIndeterminate(true);
      this.adapter_.setHeaderRowCheckboxChecked(false);
    }
  }

  /**
   * Sets the attributes of row element based on selection state.
   */
  private selectRowAtIndex_(rowIndex: number, selected: boolean) {
    if (selected) {
      this.adapter_.addClassAtRowIndex(rowIndex, cssClasses.ROW_SELECTED);
      this.adapter_.setAttributeAtRowIndex(
        rowIndex,
        strings.ARIA_SELECTED,
        "true"
      );
    } else {
      this.adapter_.removeClassAtRowIndex(rowIndex, cssClasses.ROW_SELECTED);
      this.adapter_.setAttributeAtRowIndex(
        rowIndex,
        strings.ARIA_SELECTED,
        "false"
      );
    }
  }
}