ArticleViewController

//
//  ViewController.m
//  RenderTextDemo
//
//  Created by Shubham Goyal on 10/3/12.
//  Copyright (c) 2012 [email protected]. All rights reserved.
//

#import "ArticleViewController.h"
#import "CommentsWidgetViewController.h"
#import "RatingWidgetViewController.h"
#import "RelatedArticlesWidgetViewController.h"
#import "SDURLCache.h"

#define BAR_HEIGHT 60
#define IPAD_HEIGHT 748
#define IPAD_WIDTH 1024
#define ANIMATION_DURATION 0.5
#define PADDING 50

#define articleURLFormat @"http://ec2-175-41-180-218.ap-southeast-1.compute.amazonaws.com/article/list_article_content/%u"
#define themeURLFormat @"http://ec2-175-41-180-218.ap-southeast-1.compute.amazonaws.com/publisher/get_theme/%u"
#define kJSONThemeKey @"data"
#define kJSONSuccessKey @"success"
#define kJSONErrorMessageKey @"error_msg"

@interface ArticleViewController ()

#pragma mark - Network

@property (strong, nonatomic) NSMutableData *receivedThemeData;
@property (strong, nonatomic) NSMutableData *receivedArticleData;

@end

@implementation ArticleViewController

@synthesize publisherId;
@synthesize articleId;

@synthesize pages;
@synthesize pageNumber = _pageNumber;

- (void)setPageNumber: (NSUInteger) aPageNumber {
    _pageNumber = aPageNumber;
    [[NSNotificationCenter defaultCenter] postNotificationName:@"pageNumberSet" object:@"nil"];
}

@synthesize pageViews;
@synthesize pageViewContainer;

@synthesize comments;
@synthesize rating;
@synthesize relatedArticles;
@synthesize images;
@synthesize numberOfStars;

@synthesize bar;
@synthesize ratingButton;
@synthesize isRatingButtonClicked;
@synthesize commentsButton;
@synthesize relatedArticlesButton;

@synthesize curtain;
@synthesize thumbnailContentView;
@synthesize thumbnailScrollView;

@synthesize headerView;
@synthesize themeModel;

@synthesize receivedThemeData;
@synthesize receivedArticleData;

#pragma mark - Custom initialization

- (id) initWithCoder:(NSCoder *)aDecoder {
    if (self = [super initWithCoder: aDecoder]) {
        pages = [NSMutableArray array];
        pageViews = [NSMutableArray array];
    }

    return self;
}

#pragma mark - Page layout

+ (LayoutType) layoutTypeFromString: (NSString*) aLayoutTypeString {
    if ([aLayoutTypeString isEqualToString: @"TWO_COLUMN"]) {
        return TWO_COLUMN;
    } else if ([aLayoutTypeString isEqualToString: @"THREE_COLUMN"]) {
        return THREE_COLUMN;
    } else if ([aLayoutTypeString isEqualToString: @"TWO_COLUMN_IMAGE"]) {
        return TWO_COLUMN_IMAGE;
    } else if ([aLayoutTypeString isEqualToString: @"TWO_COLUMN_VIDEO"]) {
        return TWO_COLUMN_VIDEO;
    } else {
        // TODO: Should not crash like this
        // @throw [NSException exceptionWithName: NSGenericException reason: @"Unexpected LayoutType string" userInfo: nil];
        return DEFAULT_LAYOUT;
    }
}

- (void) applyLayout:(LayoutType)layoutType toView:(UIView*)view pageData: (NSDictionary*) aPage {
    switch (layoutType) {
        case TWO_COLUMN:
        case THREE_COLUMN:
            break;
        case TWO_COLUMN_IMAGE:
            [self putImageWidgetInView: view pageData: aPage];
            break;
        case TWO_COLUMN_VIDEO:
            [self putVideoInView: view pageData: aPage];
            break;
        default:
            DLog(@"/!\\ WARNING!!! Bad LayoutType input")
            break;
    }
}

#define kYouTubeVideoHTMLFormat @"<embed src=\"%@\" type=\"application/x-shockwave-flash\" width=\"%f\" height=\"%f\"></embed>"

- (void) putVideoInView:(UIView*)view pageData: (NSDictionary*) aPage {
    UIWebView* video = [[UIWebView alloc] initWithFrame:CGRectMake(530, 155, 470, 345)];
    video.scrollView.scrollEnabled = NO;
    // TODO: Currently the server doesn't support video on other pages. Add support later.
    NSString* urlString = [aPage objectForKey: @"video"];
    NSString *html = [NSString stringWithFormat: kYouTubeVideoHTMLFormat, urlString, video.frame.size.width, video.frame.size.height];
    [video loadHTMLString:html baseURL:nil];
    [view addSubview:video];
}

#define serverBaseURL @"http://ec2-175-41-180-218.ap-southeast-1.compute.amazonaws.com/"

- (void) putImageWidgetInView: (UIView*) view pageData: (NSDictionary*) aPage {
    // TODO: Currently the server doesn't support image on other pages. Add support later.
    NSArray *imageURLStrings = [aPage objectForKey: @"images"];
    DLog(@"imageURLStrings: %@", imageURLStrings);
    NSMutableArray *imageURLs = [NSMutableArray array];

    for (NSString *URLString in imageURLStrings) {
        DLog(@"%@", [serverBaseURL stringByAppendingPathComponent:URLString])

        NSString *imageURLString = [serverBaseURL stringByAppendingString: [URLString stringByAddingPercentEscapesUsingEncoding: NSUTF8StringEncoding]];

        NSURL *imageURL = [NSURL URLWithString: imageURLString];
        if (imageURL) {
            DLog(@"%@", imageURL);
            [imageURLs addObject: imageURL];
        } else {
            DLog(@"Failed to create URL for: %@", imageURLString);
        }
    }

    self.images = [ImageWidgetViewController createImageWidgetWithImageURLs: [NSArray arrayWithArray:imageURLs] frame: CGRectMake(530, 155, 470, 345) fullScreenSuperview: self.view];
    // TODO: When to remove the child view controller?
    // TODO: Check if we need to add as child VC
    [self addChildViewController: self.images];
    [view addSubview: self.images.view];
}

#pragma mark - Theme

- (void) parseTheme: (NSData*) aData {
    NSError* jsonParsingError = nil;
    NSDictionary* responseJSON = [NSJSONSerialization JSONObjectWithData: aData options: kNilOptions error: &jsonParsingError];

    assert(responseJSON == nil ^ jsonParsingError == nil);
    if (jsonParsingError) {
        DLog(@"JSON parsing error: %@", jsonParsingError.debugDescription);
        DLog(@"Data dump: %@", [[NSString alloc] initWithData: aData encoding: NSUTF8StringEncoding]);
        return;
    }
    assert([responseJSON isKindOfClass: [NSDictionary class]]);

    BOOL isSuccess = [(NSNumber*) [responseJSON valueForKey: kJSONSuccessKey] boolValue];
    if (!isSuccess) {
        DLog(@"Error encountered on server: %@", [responseJSON valueForKey: kJSONErrorMessageKey]);
        DLog(@"Data dump: %@",  [[NSString alloc] initWithData: aData encoding: NSUTF8StringEncoding]);
        return;
    }

    NSDictionary* themeImages = [responseJSON valueForKey: kJSONThemeKey];
    assert(themeImages && [themeImages isKindOfClass: [NSDictionary class]]);
    self.themeModel = [[ThemeModel alloc] initWithDictionary: themeImages];
}

- (void) loadTheme {
    NSURL* themeURL = [[NSURL alloc] initWithString: [NSString stringWithFormat: themeURLFormat, self.publisherId]];
    NSURLRequest *themeRequest = [[NSURLRequest alloc] initWithURL: themeURL cachePolicy:NSURLRequestReloadRevalidatingCacheData timeoutInterval: 60.];

    NSURLConnection *themeConnection = [[NSURLConnection alloc] initWithRequest:themeRequest delegate:self];
    if (themeConnection) {
        self.receivedThemeData = [NSMutableData data];
    }
}

- (void) updateHeader {
    self.headerView.image = self.themeModel.primaryHeader;
}

#pragma mark - Article

#define kJSONContentKey @"content"
#define kJSONLayoutTypeKey @"layoutType"
#define kInsertCSSFormatString @"<style type=\"text/css\">h1,h2,h3,h4,h5 {color: %@;}</style>"

- (void) parseArticle: (NSData*) aData {
    NSError* jsonParsingError = nil;
    NSDictionary* responseJSON = [NSJSONSerialization JSONObjectWithData: aData options: kNilOptions error: &jsonParsingError];

    assert(responseJSON == nil ^ jsonParsingError == nil);
    if (jsonParsingError) {
        DLog(@"JSON parsing error: %@", jsonParsingError.debugDescription);
        DLog(@"Data dump: %@", [[NSString alloc] initWithData: aData encoding: NSUTF8StringEncoding]);
        return;
    }
    assert([responseJSON isKindOfClass: [NSDictionary class]]);

    BOOL isSuccess = [(NSNumber*) [responseJSON valueForKey: kJSONSuccessKey] boolValue];
    if (!isSuccess) {
        DLog(@"Error encountered on server: %@", [responseJSON valueForKey: kJSONErrorMessageKey]);
        DLog(@"Data dump: %@",  [[NSString alloc] initWithData: aData encoding: NSUTF8StringEncoding]);
        return;
    }

    NSArray *data_ = [responseJSON objectForKey: @"data"];
    NSDictionary *obj = [data_ objectAtIndex: 0];
    self.pages = [obj objectForKey: @"content"];

    NSString *colorString = [obj objectForKey: @"color"];

    int i = 0;
    for (i = 0; i < [self.pages count]; i++) {
        NSDictionary *page = [self.pages objectAtIndex: i];
        NSString *pageContent = [page objectForKey: kJSONContentKey];
        assert(pageContent);

        // TODO: Remove this hack!!!
        UIWebView* pageView = [[UIWebView alloc] initWithFrame:CGRectMake(i * IPAD_WIDTH, 30, IPAD_WIDTH, IPAD_HEIGHT - BAR_HEIGHT)];
        pageView.delegate = self;

        NSString* css = [NSString stringWithFormat: kInsertCSSFormatString, colorString];
        pageContent = [css stringByAppendingString: pageContent];

        [pageView loadHTMLString: pageContent baseURL:nil];
        pageView.scrollView.scrollEnabled = NO;
        [self.pageViews addObject:pageView];
        [self.pageViewContainer insertSubview: pageView atIndex:i];

        UISwipeGestureRecognizer *leftSwipeGestureRecognizer = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(handleLeftSwipeGesture:)];
        leftSwipeGestureRecognizer.direction = UISwipeGestureRecognizerDirectionLeft;
        [pageView addGestureRecognizer:leftSwipeGestureRecognizer];

        UISwipeGestureRecognizer *rightSwipeGestureRecognizer = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(handleRightSwipeGesture:)];
        rightSwipeGestureRecognizer.direction = UISwipeGestureRecognizerDirectionRight;
        [pageView addGestureRecognizer:rightSwipeGestureRecognizer];

        NSString *layoutTypeString = [page objectForKey: kJSONLayoutTypeKey];
        assert(layoutTypeString);
        LayoutType layoutType = [ArticleViewController layoutTypeFromString: layoutTypeString];

        [self applyLayout:layoutType toView:pageView pageData: page];
    }

    self.pageNumber = 0;
}

- (void) loadArticleContent {
    NSURL* articleURL = [[NSURL alloc] initWithString: [NSString stringWithFormat: articleURLFormat, self.articleId]];
    NSURLRequest *articleRequest = [[NSURLRequest alloc] initWithURL: articleURL cachePolicy:NSURLRequestReloadRevalidatingCacheData timeoutInterval: 60.];
    NSURLConnection *articleConnection = [[NSURLConnection alloc] initWithRequest:articleRequest delegate:self];
    if (articleConnection) {
        self.receivedArticleData = [NSMutableData data];
    }
}

- (void) handleLeftSwipeGesture:(UISwipeGestureRecognizer*)swipeGestureRecognizer {
    if (self.pageNumber < self.pages.count - 1)
        self.pageNumber += 1;
}

- (void) handleRightSwipeGesture:(UISwipeGestureRecognizer*)swipeGestureRecognizer {
    if (self.pageNumber > 0)
        self.pageNumber -= 1;

}

- (void) updatePagesView {
    [UIView animateWithDuration:ANIMATION_DURATION animations:^{
        // For consistency
        int currentPage = self.pageNumber;

        int i = 0;
        for (UIView* page in self.pageViews) {
            page.center = CGPointMake((i - currentPage) * IPAD_WIDTH + IPAD_WIDTH / 2, page.center.y);

            i++;
        }
    }];
}

- (BOOL)webView:(UIWebView *)webView shouldStartLoadWithRequest:(NSURLRequest *)request navigationType:(UIWebViewNavigationType)navigationType {
    // TODO: Pop up a browser like Flipboard
    return navigationType != UIWebViewNavigationTypeLinkClicked;
}

#pragma mark - Overview

// UIScrollViewDelegate function
- (UIView *)viewForZoomingInScrollView:(UIScrollView *)scrollView {
    if (scrollView == self.thumbnailScrollView)
        return self.thumbnailContentView;
    else
        return nil;
}

- (void) handleSelectPage: (UITapGestureRecognizer*) sender {
    DLog(@"Detected tap gesture");
    DLog(@"%d", [self.thumbnailContentView.subviews indexOfObject: sender.view]);
    self.pageNumber = [self.thumbnailContentView.subviews indexOfObject: sender.view];
    [self closeOverview];
}

- (void) openOverview {
    for (UIView* thumbnailImageView in self.thumbnailContentView.subviews) {
        [thumbnailImageView removeFromSuperview];
    }

    int i = 0;
    for (UIView* page in self.pageViews) {
        UIGraphicsBeginImageContext(page.frame.size);
        [[page layer] renderInContext: UIGraphicsGetCurrentContext()];
        UIImage* webPageImage = UIGraphicsGetImageFromCurrentImageContext();
        UIGraphicsEndImageContext();


        UIView* thumbnailView = [[UIView alloc] initWithFrame: CGRectMake(i * (self.pageViewContainer.frame.size.width + PADDING), 0, self.pageViewContainer.frame.size.width, self.pageViewContainer.frame.size.height)];

        UIImageView *webPageImageView = [[UIImageView alloc] initWithImage: webPageImage];
        webPageImageView.frame = CGRectMake(0, 30, webPageImageView.frame.size.width, webPageImageView.frame.size.height);

        UIImageView *headerImageView = [[UIImageView alloc] initWithFrame: CGRectMake(0, 0, 1024, 130)];
        headerImageView.image = self.headerView.image;

        [thumbnailView addSubview: webPageImageView];
        [thumbnailView addSubview: headerImageView];

        [self.thumbnailContentView addSubview: thumbnailView];

        UITapGestureRecognizer *tap = [[UITapGestureRecognizer alloc] initWithTarget: self action: @selector(handleSelectPage:)];
        tap.numberOfTapsRequired = 1;
        [thumbnailView addGestureRecognizer: tap];

        i++;
    }

    self.thumbnailContentView.frame = CGRectMake(0, 0, MAX(0, (IPAD_WIDTH + PADDING) * self.pages.count- PADDING), IPAD_HEIGHT - BAR_HEIGHT);
    self.thumbnailScrollView.contentSize = CGSizeMake(MAX(self.thumbnailContentView.frame.size.width * self.thumbnailScrollView.zoomScale, self.thumbnailScrollView.frame.size.width), self.thumbnailScrollView.frame.size.height);

    [UIView beginAnimations: @"ProtonReader.ArticleViewController.overviewButtonPressed.open" context: nil];
    [UIView setAnimationDuration: 0.3];
    self.curtain.hidden = NO;

    self.thumbnailScrollView.frame = CGRectMake(0, self.pageViewContainer.frame.size.height - self.thumbnailScrollView.frame.size.height, self.thumbnailScrollView.frame.size.width, self.thumbnailScrollView.frame.size.height);
    [UIView commitAnimations];

    DLog(@"%f %f %f %f", self.thumbnailScrollView.frame.origin.x, self.thumbnailScrollView.frame.origin.y, self.thumbnailScrollView.frame.size.width, self.thumbnailScrollView.frame.size.height);
}

- (void) closeOverview {
    [UIView beginAnimations: @"ProtonReader.ArticleViewController.overviewButtonPressed.close" context: nil];
    [UIView setAnimationDuration: 0.3];
    self.curtain.hidden = YES;

    self.thumbnailScrollView.frame = CGRectMake(0, 768, self.thumbnailScrollView.frame.size.width, self.thumbnailScrollView.frame.size.height);

    [UIView commitAnimations];

    DLog(@"%f %f %f %f", self.thumbnailScrollView.frame.origin.x, self.thumbnailScrollView.frame.origin.y, self.thumbnailScrollView.frame.size.width, self.thumbnailScrollView.frame.size.height);
}

#pragma mark - Article view

- (void) loadArticle: (NSUInteger) anArticleId {
    for (UIView* view in self.pageViews) {
        [view removeFromSuperview];
    }
    [self.pageViews removeAllObjects];

    self.images = nil;
    // [self.comments.view removeFromSuperview];
    [self.comments.background removeFromSuperview];
    // [self.rating.view removeFromSuperview];
    [self.rating.rateView removeFromSuperview];
    [self.relatedArticles.view removeFromSuperview];
    [self closeOverview];


    self.articleId = anArticleId;
    [self loadArticleContent];
    self.comments = [[CommentsWidgetViewController alloc] initWithMainController:self];
    self.rating = [[RatingWidgetViewController alloc] initWithMainController:self];
    self.relatedArticles = [[RelatedArticlesWidgetViewController alloc] initWithMainController:self];
}


#pragma mark - View life cycle

- (void)viewDidLoad
{
    [super viewDidLoad];

    // TODO: Do we need to remove the observer?
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(updatePagesView) name:@"pageNumberSet" object:nil];

    self.thumbnailScrollView.delegate = self;
    self.thumbnailScrollView.zoomScale =
    self.thumbnailScrollView.minimumZoomScale =
    self.thumbnailScrollView.maximumZoomScale = self.thumbnailScrollView.frame.size.height / self.pageViewContainer.frame.size.height;

    [self loadTheme];
    [self loadArticle: self.articleId];
    // [self.comments viewDidLoad];
}


- (void)viewDidUnload
{
    [self setRating:nil];
    [self setComments:nil];
    [self setRelatedArticles:nil];

    [self setBar:nil];
    [self setRatingButton:nil];
    [self setCommentsButton:nil];
    [self setRelatedArticlesButton:nil];

    [self.pageViews removeAllObjects];

    [self setHeaderView:nil];

    [self setCurtain:nil];
    [self setThumbnailContentView:nil];
    [self setThumbnailScrollView:nil];

    [self setPageViewContainer:nil];

    [super viewDidUnload];
}

- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
{
    return UIInterfaceOrientationIsLandscape(interfaceOrientation);
}

#pragma mark - Network

- (void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)response
{
    if ([[connection.originalRequest.URL.absoluteString stringByDeletingLastPathComponent]
         isEqual: [themeURLFormat stringByDeletingLastPathComponent]]) {
        [self.receivedThemeData setLength: 0];
    }
    else if ([[connection.originalRequest.URL.absoluteString stringByDeletingLastPathComponent]
              isEqual: [articleURLFormat stringByDeletingLastPathComponent]]) {
        [self.receivedArticleData setLength: 0];
    }
    else {
        assert(0);
    }
}

- (void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data
{
    if ([[connection.originalRequest.URL.absoluteString stringByDeletingLastPathComponent]
         isEqual: [themeURLFormat stringByDeletingLastPathComponent]]) {
        [self.receivedThemeData appendData: data];
    }
    else if ([[connection.originalRequest.URL.absoluteString stringByDeletingLastPathComponent]
              isEqual: [articleURLFormat stringByDeletingLastPathComponent]]) {
        [self.receivedArticleData appendData:data];
    }
    else {
        assert(0);
    }
}

- (void)connection:(NSURLConnection *)connection didFailWithError:(NSError *)error
{
    DLog(@"Connection failed - %@", error.debugDescription);

    NSCachedURLResponse* cachedResponse = [[SDURLCache sharedURLCache] cachedResponseForRequest:connection.originalRequest];

    if (cachedResponse) {
        DLog(@"Cached response for %@ found.", connection.originalRequest.URL);

        if ([[connection.originalRequest.URL.absoluteString stringByDeletingLastPathComponent]
             isEqual: [themeURLFormat stringByDeletingLastPathComponent]]) {
            DLog(@"Theme");
            self.receivedThemeData = nil;

            [self parseTheme: cachedResponse.data];
            [self updateHeader];
        }
        else if ([[connection.originalRequest.URL.absoluteString stringByDeletingLastPathComponent]
                  isEqual: [articleURLFormat stringByDeletingLastPathComponent]]) {
            DLog(@"Article");
            self.receivedArticleData = nil;

            [self parseArticle: cachedResponse.data];
        }
        else {
            assert(0);
        }
    } else {
        DLog(@"Cached response not found for %@.", connection.originalRequest.URL);
        if ([[connection.originalRequest.URL.absoluteString stringByDeletingLastPathComponent]
             isEqual: [themeURLFormat stringByDeletingLastPathComponent]]) {
            DLog(@"Theme");
            self.receivedThemeData = nil;
        }
        else if ([[connection.originalRequest.URL.absoluteString stringByDeletingLastPathComponent]
                  isEqual: [articleURLFormat stringByDeletingLastPathComponent]]) {
            DLog(@"Article");
            self.receivedArticleData = nil;
        }
        else {
            assert(0);
        }
    }
}

- (void)connectionDidFinishLoading:(NSURLConnection *)connection
{
    if ([[connection.originalRequest.URL.absoluteString stringByDeletingLastPathComponent]
         isEqual: [themeURLFormat stringByDeletingLastPathComponent]]) {
        DLog(@"Theme");
        [self parseTheme: self.receivedThemeData];
        self.receivedThemeData = nil;

        [self updateHeader];
    }
    else if ([[connection.originalRequest.URL.absoluteString stringByDeletingLastPathComponent]
              isEqual: [articleURLFormat stringByDeletingLastPathComponent]]) {
        DLog(@"Article");
        [self parseArticle: self.receivedArticleData];
        self.receivedArticleData = nil;
    }
    else {
        assert(0);
    }
}

#pragma mark - Action handler

- (IBAction)ratingButtonPressed:(id)sender {
    if (isRatingButtonClicked) {
        [self.rating viewDidUnload];
    }
    else {
        if (self.rating.rateView != nil) {
            [self.rating.rateView removeFromSuperview];
            self.rating.rateView = nil;
        }
        [self.rating viewDidLoad];
    }
    self.isRatingButtonClicked = !self.isRatingButtonClicked;
}

- (IBAction)commentsButtonPressed:(id)sender {
    [self.comments buttonPressed:sender];
}

- (IBAction)relatedArticlesButtonPressed:(UIButton *)sender {
    [self.relatedArticles buttonPressed:sender];
}

- (IBAction)homeButtonPressed:(id)sender {
    UINavigationController *navigationController = self.navigationController;
    [navigationController popToRootViewControllerAnimated: YES];
}

- (IBAction)tappedOnCurtain:(id)sender {
    [self closeOverview];
}

- (IBAction)overviewButtonPressed:(id)sender {
    if (self.curtain.hidden) {
        [self openOverview];
    } else {
        [self closeOverview];
    }
}

- (IBAction)backButtonPressed:(id)sender {
    [self.navigationController popViewControllerAnimated: YES];
}

@end