/*
 Copyright 2017 Vector Creations Ltd

 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 "DirectoryServerPickerViewController.h"
#import "DirectoryServerTableViewCell.h"
#import "DirectoryServerDetailTableViewCell.h"

#import "AppDelegate.h"

@interface DirectoryServerPickerViewController ()
{
    MXKDirectoryServersDataSource *dataSource;

    // Observe kAppDelegateDidTapStatusBarNotification to handle tap on clock status bar.
    id kAppDelegateDidTapStatusBarNotificationObserver;

    void (^onCompleteBlock)(id<MXKDirectoryServerCellDataStoring> cellData);

    // Current alert (if any).
    MXKAlert *currentAlert;

    // Current request in progress.
    MXHTTPOperation *mxCurrentOperation;
}
@end

@implementation DirectoryServerPickerViewController

- (void)finalizeInit
{
    [super finalizeInit];

    // Setup `MXKViewControllerHandling` properties
    self.defaultBarTintColor = kRiotNavBarTintColor;
    self.enableBarTintColorStatusChange = NO;
    self.rageShakeManager = [RageShakeManager sharedManager];
}

- (void)destroy
{
    dataSource.delegate = nil;
    dataSource = nil;
    onCompleteBlock = nil;

    if (kAppDelegateDidTapStatusBarNotificationObserver)
    {
        [[NSNotificationCenter defaultCenter] removeObserver:kAppDelegateDidTapStatusBarNotificationObserver];
        kAppDelegateDidTapStatusBarNotificationObserver = nil;
    }

    // Close any pending actionsheet
    if (currentAlert)
    {
        [currentAlert dismiss:NO];
        currentAlert = nil;
    }

    if (mxCurrentOperation)
    {
        [mxCurrentOperation cancel];
        mxCurrentOperation = nil;
    }

    [super destroy];
}

- (void)viewDidLoad
{
    [super viewDidLoad];

    self.title = NSLocalizedStringFromTable(@"directory_server_picker_title", @"Vector", nil);

    self.tableView.delegate = self;

    // Register view cell classes
    [self.tableView registerClass:DirectoryServerTableViewCell.class forCellReuseIdentifier:DirectoryServerTableViewCell.defaultReuseIdentifier];
    [self.tableView registerClass:DirectoryServerDetailTableViewCell.class forCellReuseIdentifier:DirectoryServerDetailTableViewCell.defaultReuseIdentifier];

    // Add a cancel button
    self.navigationItem.leftBarButtonItem = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemCancel target:self action:@selector(onCancel:)];
    self.navigationItem.leftBarButtonItem.accessibilityIdentifier = @"DirectoryServerPickerVCCancelButton";

    // Add a + button
    self.navigationItem.rightBarButtonItem = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemAdd target:self action:@selector(onAdd:)];
    self.navigationItem.rightBarButtonItem.accessibilityIdentifier = @"DirectoryServerPickerVCAddButton";

    // Hide line separators of empty cells
    self.tableView.tableFooterView = [[UIView alloc] init];
}

- (void)viewWillAppear:(BOOL)animated
{
    [super viewWillAppear:animated];

    // Screen tracking (via Google Analytics)
    id<GAITracker> tracker = [[GAI sharedInstance] defaultTracker];
    if (tracker)
    {
        [tracker set:kGAIScreenName value:@"DirectoryServerPicker"];
        [tracker send:[[GAIDictionaryBuilder createScreenView] build]];
    }

    // Observe kAppDelegateDidTapStatusBarNotificationObserver.
    kAppDelegateDidTapStatusBarNotificationObserver = [[NSNotificationCenter defaultCenter] addObserverForName:kAppDelegateDidTapStatusBarNotification object:nil queue:[NSOperationQueue mainQueue] usingBlock:^(NSNotification *notif) {

        [self.tableView setContentOffset:CGPointMake(-self.tableView.contentInset.left, -self.tableView.contentInset.top) animated:YES];

    }];

    [dataSource loadData];
}

- (void)viewWillDisappear:(BOOL)animated
{
    if (kAppDelegateDidTapStatusBarNotificationObserver)
    {
        [[NSNotificationCenter defaultCenter] removeObserver:kAppDelegateDidTapStatusBarNotificationObserver];
        kAppDelegateDidTapStatusBarNotificationObserver = nil;
    }

    [super viewWillDisappear:animated];
}

- (void)displayWithDataSource:(MXKDirectoryServersDataSource*)theDataSource
                   onComplete:(void (^)(id<MXKDirectoryServerCellDataStoring> cellData))onComplete;
{
    dataSource = theDataSource;
    onCompleteBlock = onComplete;

    // Let the data source provide cells
    self.tableView.dataSource = dataSource;

    dataSource.delegate = self;
}

#pragma mark - MXKDataSourceDelegate

- (Class<MXKCellRendering>)cellViewClassForCellData:(MXKCellData*)cellData
{
    id<MXKDirectoryServerCellDataStoring> directoryCellData = (id<MXKDirectoryServerCellDataStoring>)cellData;

    if (directoryCellData.homeserver)
    {
        return DirectoryServerDetailTableViewCell.class;
    }
    return DirectoryServerTableViewCell.class;
}

- (NSString *)cellReuseIdentifierForCellData:(MXKCellData*)cellData
{
    id<MXKDirectoryServerCellDataStoring> directoryCellData = (id<MXKDirectoryServerCellDataStoring>)cellData;

    if (directoryCellData.homeserver)
    {
        return DirectoryServerDetailTableViewCell.defaultReuseIdentifier;
    }
    return DirectoryServerTableViewCell.defaultReuseIdentifier;
}

- (void)dataSource:(MXKDataSource*)dataSource didCellChange:(id /* @TODO*/)changes
{
    [self.tableView reloadData];
}

- (void)dataSource:(MXKDataSource*)dataSource2 didStateChange:(MXKDataSourceState)state
{
    if (state == MXKDataSourceStatePreparing)
    {
        [self startActivityIndicator];
    }
    else
    {
        [self stopActivityIndicator];
        [self.tableView reloadData];
    }
}


#pragma mark - UITableViewDelegate

- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
{
    return DirectoryServerTableViewCell.cellHeight;
}

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
    id<MXKDirectoryServerCellDataStoring> cellData = [dataSource cellDataAtIndexPath:indexPath];

    if (onCompleteBlock)
    {
        onCompleteBlock(cellData);
    }

    [self withdrawViewControllerAnimated:YES completion:nil];
}

#pragma mark - User actions

- (IBAction)onCancel:(id)sender
{
    if (onCompleteBlock)
    {
        onCompleteBlock(nil);
    }

    [self withdrawViewControllerAnimated:YES completion:nil];
}

- (IBAction)onAdd:(id)sender
{
    __weak typeof(self) weakSelf = self;

    [currentAlert dismiss:NO];

    // Prompt the user to enter a homeserver
    currentAlert = [[MXKAlert alloc] initWithTitle:nil message:NSLocalizedStringFromTable(@"directory_server_type_homeserver", @"Vector", nil) style:MXKAlertStyleAlert];

    [currentAlert addTextFieldWithConfigurationHandler:^(UITextField *textField) {

        textField.secureTextEntry = NO;
        textField.placeholder = NSLocalizedStringFromTable(@"directory_server_placeholder", @"Vector", nil);
        textField.keyboardType = UIKeyboardTypeDefault;
    }];

    currentAlert.cancelButtonIndex = [currentAlert addActionWithTitle:[NSBundle mxk_localizedStringForKey:@"cancel"] style:MXKAlertActionStyleDefault handler:^(MXKAlert *alert) {

        if (weakSelf)
        {
            typeof(self) self = weakSelf;
            self->currentAlert = nil;
        }

    }];

    [currentAlert addActionWithTitle:[NSBundle mxk_localizedStringForKey:@"ok"] style:MXKAlertActionStyleDefault handler:^(MXKAlert *alert) {

        if (weakSelf)
        {
            UITextField *textField = [alert textFieldAtIndex:0];

            typeof(self) self = weakSelf;
            self->currentAlert = nil;

            NSString *homeserver = textField.text;
            if (homeserver.length)
            {
                // Test if the homeserver exists
                [self.activityIndicator startAnimating];

                self->mxCurrentOperation = [self->dataSource.mxSession.matrixRestClient publicRoomsOnServer:homeserver limit:20 since:nil filter:nil thirdPartyInstanceId:nil includeAllNetworks:YES success:^(MXPublicRoomsResponse *publicRoomsResponse) {

                    if (weakSelf && self->mxCurrentOperation)
                    {
                        // The homeserver is valid
                        self->mxCurrentOperation = nil;
                        [self.activityIndicator stopAnimating];

                        if (self->onCompleteBlock)
                        {
                            // Prepare response argument
                            MXKDirectoryServerCellData *cellData = [[MXKDirectoryServerCellData alloc] initWithHomeserver:homeserver includeAllNetworks:YES];

                            self->onCompleteBlock(cellData);
                        }

                        [self withdrawViewControllerAnimated:YES completion:nil];
                    }

                } failure:^(NSError *error) {

                    if (weakSelf && self->mxCurrentOperation)
                    {
                        // The homeserver is not valid
                        self->mxCurrentOperation = nil;
                        [self.activityIndicator stopAnimating];

                        [[AppDelegate theDelegate] showErrorAsAlert:error];
                    }

                }];
            }
        }
    }];

    [currentAlert showInViewController:self];
}


@end