/*
 * Copyright 2021 Google LLC
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#import "DataPickerState.h"
#import "DataPickerViewController.h"

@implementation DataPickerViewController

- (id)initWithNibName:(NSString *)nibNameOrNil
               bundle:(NSBundle *)nibBundleOrNil
            dataState:(DataPickerState *)dataState {
  self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
  if (self) {
    _dataState = dataState;
  }
  return self;
}

#pragma mark - Table view data source

- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView {
  return 1;
}

- (NSInteger)tableView:(UITableView *)tableView
    numberOfRowsInSection:(NSInteger)section {
  return [self.dataState.cellLabels count];
}

- (UITableViewCell *)tableView:(UITableView *)tableView
         cellForRowAtIndexPath:(NSIndexPath *)indexPath {
  static NSString * const kCellIdentifier = @"Cell";
  UITableViewCell *cell =
      [tableView dequeueReusableCellWithIdentifier:kCellIdentifier];

  if (cell == nil) {
    cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault
                                  reuseIdentifier:kCellIdentifier];
  }

  NSDictionary *cellLabelDict = self.dataState.cellLabels[indexPath.row];
  NSString *cellLabelText = cellLabelDict[kLabelKey];
  if ([cellLabelDict objectForKey:kShortLabelKey]) {
    cellLabelText = [cellLabelDict objectForKey:kShortLabelKey];
  }
  cell.textLabel.text = cellLabelText;
  // If the cell is selected, mark it as checked
  if ([self.dataState.selectedCells containsObject:cellLabelDict[kLabelKey]]) {
    cell.accessoryType = UITableViewCellAccessoryCheckmark;
  } else {
    cell.accessoryType = UITableViewCellAccessoryNone;
  }
  return cell;
}

#pragma mark - Table view delegate

- (void)tableView:(UITableView *)tableView
    didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
  UITableViewCell *selectedCell = [tableView cellForRowAtIndexPath:indexPath];
  NSDictionary *selectedCellDict = _dataState.cellLabels[indexPath.row];
  NSString *label = selectedCellDict[kLabelKey];

  if (self.dataState.multipleSelectEnabled) {
    // If multiple selections are allowed, then toggle the state
    // of the selected cell
    if ([self.dataState.selectedCells containsObject:label]) {
      [self.dataState.selectedCells removeObject:label];
      selectedCell.accessoryType = UITableViewCellAccessoryNone;
    } else {
      [self.dataState.selectedCells addObject:label];
      selectedCell.accessoryType = UITableViewCellAccessoryCheckmark;
    }
  } else {
    // Set all cells to unchecked except for the one that was just selected
    [self.dataState.selectedCells removeAllObjects];
    [self.dataState.selectedCells addObject:label];

    for (NSIndexPath *curPath in [self.tableView indexPathsForVisibleRows]) {
      UITableViewCell *cell = [self.tableView cellForRowAtIndexPath:curPath];
      if (curPath.row == indexPath.row) {
        cell.accessoryType = UITableViewCellAccessoryCheckmark;
      } else {
        cell.accessoryType = UITableViewCellAccessoryNone;
      }
    }
  }
  [self.tableView deselectRowAtIndexPath:indexPath animated:YES];
}

@end