use notifications to communicate changes to posts

Blog/BlogController.h

@@ -8,16 +8,6 @@
 
 @import Foundation;
 
-extern NSString *BlogStatusChangedNotification;
-extern NSString *BlogDraftsChangedNotification;
-extern NSString *BlogDraftAddedNotification;
-extern NSString *BlogDraftRemovedNotification;
-extern NSString *BlogPublishedPostsChangedNotification;
-extern NSString *BlogPublishedPostAddedNotification;
-extern NSString *BlogPublishedPostRemovedNotification;
-extern NSString *BlogPostChangedNotification;
-extern NSString *BlogPostDeletedNotification;
-
 @class PMKPromise;
 @class ModelStore;
 @class BlogService;
@@ -39,9 +29,9 @@ extern NSString *BlogPostDeletedNotification;
 
 - (PMKPromise *)requestCreateDraft:(Post *)draft;
 - (PMKPromise *)requestUpdatePost:(Post *)post;
-- (PMKPromise *)requestPublishDraftWithPath:(NSString *)path;
+- (PMKPromise *)requestPublishDraft:(Post *)post;
-- (PMKPromise *)requestUnpublishPostWithPath:(NSString *)path;
+- (PMKPromise *)requestUnpublishPost:(Post *)post;
-- (PMKPromise *)requestDeletePostWithPath:(NSString *)path;
+- (PMKPromise *)requestDeletePost:(Post *)post;
 
 - (PMKPromise *)requestPublishToStagingEnvironment;
 - (PMKPromise *)requestPublishToProductionEnvironment;

Blog/BlogController.m

@@ -13,16 +13,6 @@
 #import "BlogStatus.h"
 #import "Post.h"
 
-NSString *BlogStatusChangedNotification = @"BlogStatusChangedNotification";
-NSString *BlogDraftsChangedNotification = @"BlogDraftsChangedNotification";
-NSString *BlogDraftAddedNotification = @"BlogDraftAddedNotification";
-NSString *BlogDraftRemovedNotification = @"BlogDraftRemovedNotification";
-NSString *BlogPublishedPostsChangedNotification = @"BlogPublishedPostsChangedNotification";
-NSString *BlogPublishedPostAddedNotification = @"BlogPostAddedNotification";
-NSString *BlogPublishedPostRemovedNotification = @"BlogPostRemovedNotification";
-NSString *BlogPostChangedNotification = @"BlogPostChangedNotification";
-NSString *BlogPostDeletedNotification = @"BlogPostDeletedNotification";
-
 @implementation BlogController {
     BlogService *_service;
     ModelStore *_store;
@@ -113,26 +103,26 @@ NSString *BlogPostDeletedNotification = @"BlogPostDeletedNotification";
             });
 }
 
-- (PMKPromise *)requestPublishDraftWithPath:(NSString *)path {
+- (PMKPromise *)requestPublishDraft:(Post *)post {
-    return [_service requestPublishDraftWithPath:path].then(^(Post *post) {
+    return [_service requestPublishDraftWithPath:post.path].then(^(Post *post) {
-        [_store removeDraftWithPath:path];
+        [_store removeDraft:post];
         [_store addPublishedPost:post];
         return post;
     });
 }
 
-- (PMKPromise *)requestUnpublishPostWithPath:(NSString *)path {
+- (PMKPromise *)requestUnpublishPost:(Post *)post {
-    return [_service requestUnpublishPostWithPath:path].then(^(Post *post) {
+    return [_service requestUnpublishPostWithPath:post.path].then(^(Post *post) {
-        [_store removePostWithPath:path];
+        [_store removePost:post];
         [_store addDraft:post];
         return post;
     });
 }
 
-- (PMKPromise *)requestDeletePostWithPath:(NSString *)path {
+- (PMKPromise *)requestDeletePost:(Post *)post {
-    return [_service requestDeletePostWithPath:path].then(^(id _) {
+    return [_service requestDeletePostWithPath:post.path].then(^(id _) {
-        [_store removePostWithPath:path];
+        [_store removePost:post];
-        [_store removeDraftWithPath:path];
+        [_store removeDraft:post];
         return _;
     });
 }

Blog/EditorViewController.h

@@ -15,7 +15,6 @@
 
 @property (nonatomic, strong) BlogController *blogController;
 @property (nonatomic, strong) Post *post;
-@property (nonatomic, copy) void (^postUpdatedBlock)(Post *post);
 
 - (void)configureWithPost:(Post *)post;
 

Blog/EditorViewController.m

@@ -12,6 +12,7 @@
 #import "Post.h"
 #import "PreviewViewController.h"
 #import "ChangeTitleViewController.h"
+#import "ModelStore.h"
 
 @interface EditorViewController () <UITextViewDelegate, UIPopoverPresentationControllerDelegate>
 
@@ -74,7 +75,7 @@
 #pragma mark - Managing the detail item
 
 - (void)configureWithPost:(Post *)post {
-    if (![post isEqual:self.post]) {
+    if (!(post && [post isEqual:self.post])) {
         self.post = post;
         self.modifiedPost = post;
         [self configureView];
@@ -93,6 +94,12 @@
 }
 
 - (void)configureTitleView {
+    if (!self.post) {
+        self.titleLabel.text = nil;
+        self.statusLabel.text = nil;
+        return;
+    }
+
     self.titleLabel.text = self.modifiedPost.title.length ? self.modifiedPost.title : @"Untitled";
     NSString *statusText = [self statusText];
     if (self.statusLabel && ![self.statusLabel.text isEqualToString:statusText]) {
@@ -111,7 +118,7 @@
 
 - (void)configureLinkView {
     NSURL *url = self.modifiedPost.url;
-    if (url || [self pasteboardHasLink]) {
+    if (self.post && url || [self pasteboardHasLink]) {
         NSString *title = url ? url.absoluteString : @"Add Link from Pasteboard";
         [self.linkButton setTitle:title forState:UIControlStateNormal];
         self.removeLinkButton.hidden = !url;
@@ -136,7 +143,6 @@
     CGPoint scrollOffset = CGPointZero;
     Post *post = self.modifiedPost;
     if (post) {
-        // FIXME: date, status (draft, published)
         body = post.body;
         // TODO: restore scroll offset for this post ... user defaults?
     }
@@ -166,10 +172,13 @@
 
 - (void)viewWillAppear:(BOOL)animated {
     [super viewWillAppear:animated];
+    NSAssert(self.blogController, @"blogController is required");
     NSNotificationCenter *notificationCenter = [NSNotificationCenter defaultCenter];
     [notificationCenter addObserver:self selector:@selector(applicationWillResignActive:) name:UIApplicationWillResignActiveNotification object:nil];
     [notificationCenter addObserver:self selector:@selector(keyboardWillShow:) name:UIKeyboardWillShowNotification object:nil];
     [notificationCenter addObserver:self selector:@selector(keyboardWillHide:) name:UIKeyboardWillHideNotification object:nil];
+    [notificationCenter addObserver:self selector:@selector(postDeleted:) name:DraftRemovedNotification object:nil];
+    [notificationCenter addObserver:self selector:@selector(postDeleted:) name:PublishedPostRemovedNotification object:nil];
     [self configureView];
 }
 
@@ -179,6 +188,8 @@
     [notificationCenter removeObserver:self name:UIApplicationWillResignActiveNotification object:nil];
     [notificationCenter removeObserver:self name:UIKeyboardWillShowNotification object:nil];
     [notificationCenter removeObserver:self name:UIKeyboardWillHideNotification object:nil];
+    [notificationCenter removeObserver:self name:DraftRemovedNotification object:nil];
+    [notificationCenter removeObserver:self name:PublishedPostRemovedNotification object:nil];
     [self savePost];
 }
 
@@ -208,6 +219,13 @@
     [self hideHideKeyboardButton];
 }
 
+- (void)postDeleted:(NSNotification *)note {
+    NSString *path = note.userInfo[PostPathUserInfoKey];
+    if ([path isEqualToString:self.post.path]) {
+        [self configureWithPost:nil];
+    }
+}
+
 #pragma mark - State restoration
 
 static NSString *const StateRestorationPostKey = @"post";
@@ -247,7 +265,7 @@ static NSString *const StateRestorationModifiedPostKey = @"modifiedPost";
 
 - (BOOL)isDirty;
 {
-    return self.modifiedPost.new || ![self.modifiedPost isEqualToPost:self.post];
+    return self.post && (self.modifiedPost.new || ![self.modifiedPost isEqualToPost:self.post]);
 }
 
 - (PMKPromise *)savePost {
@@ -293,9 +311,6 @@ static NSString *const StateRestorationModifiedPostKey = @"modifiedPost";
 
         // update our post because "new" may have changed, which is essential to correct operation
         [self configureWithPost:newPost];
-        if (self.postUpdatedBlock) {
-            self.postUpdatedBlock(self.post);
-        }
         return newPost;
     }).catch(^(NSError *error) {
         NSLog(@"Failed to %@ post at path %@: %@ %@", verb, path, error.localizedDescription, error.userInfo);
@@ -332,18 +347,15 @@ static NSString *const StateRestorationModifiedPostKey = @"modifiedPost";
         PMKPromise *promise = nil;
         Post *post = self.modifiedPost;
         if (post.draft) {
-            promise = [self.blogController requestPublishDraftWithPath:post.path];
+            promise = [self.blogController requestPublishDraft:post];
         }
         else {
-            promise = [self.blogController requestUnpublishPostWithPath:post.path];
+            promise = [self.blogController requestUnpublishPost:post];
         }
         promise.then(^(Post *post) {
             self.post = post;
             self.modifiedPost = post;
             [self configureView];
-            if (self.postUpdatedBlock) {
-                self.postUpdatedBlock(post);
-            }
         });
     });
 }

Blog/ModelStore.h

@@ -8,6 +8,14 @@
 
 #import <Foundation/Foundation.h>
 
+extern NSString *const PostUpdatedNotification;
+extern NSString *const DraftRemovedNotification;
+extern NSString *const DraftAddedNotification;
+extern NSString *const PublishedPostAddedNotification;
+extern NSString *const PublishedPostRemovedNotification;
+extern NSString *const PostUserInfoKey;
+extern NSString *const PostPathUserInfoKey;
+
 @class PMKPromise;
 @class YapDatabaseConnection;
 @class BlogStatus;
@@ -31,7 +39,7 @@
 - (PMKPromise *)addDraft:(Post *)post;
 - (PMKPromise *)addPublishedPost:(Post *)post;
 
-- (PMKPromise *)removeDraftWithPath:(NSString *)path;
+- (PMKPromise *)removeDraft:(Post *)post;
-- (PMKPromise *)removePostWithPath:(NSString *)path;
+- (PMKPromise *)removePost:(Post *)post;
 
 @end

Blog/ModelStore.m

@@ -13,6 +13,14 @@
 #import "Post.h"
 #import "NSArray+ObjectiveSugar.h"
 
+NSString *const PostUpdatedNotification = @"PostUpdatedNotification";
+NSString *const DraftRemovedNotification = @"DraftRemovedNotification";
+NSString *const DraftAddedNotification = @"DraftAddedNotification";
+NSString *const PublishedPostAddedNotification = @"PublishedPostAddedNotification";
+NSString *const PublishedPostRemovedNotification = @"PublishedPostRemovedNotification";
+NSString *const PostUserInfoKey = @"PostUserInfoKey";
+NSString *const PostPathUserInfoKey = @"PostPathUserInfoKey";
+
 @implementation ModelStore {
     YapDatabaseConnection *_connection;
 }
@@ -50,6 +58,11 @@
     }];
 }
 
+- (void)postPostUpdatedNotificationForPost:(Post *)post {
+    NSDictionary *info = @{PostPathUserInfoKey : post.path, PostUserInfoKey : post};
+    [[NSNotificationCenter defaultCenter] postNotificationName:PostUpdatedNotification object:self userInfo:info];
+}
+
 - (Post *)postWithPath:(NSString *)path {
     __block Post *post = nil;
     [_connection readWithBlock:^(YapDatabaseReadTransaction *transaction) {
@@ -63,6 +76,7 @@
         [_connection asyncReadWriteWithBlock:^(YapDatabaseReadWriteTransaction *transaction) {
             [transaction setObject:post forKey:post.path inCollection:@"Post"];
         } completionBlock:^{
+            [self postPostUpdatedNotificationForPost:post];
             fulfill(post);
         }];
     }];
@@ -111,21 +125,25 @@
                 [transaction setObject:postPaths forKey:@"drafts" inCollection:@"PostCollection"];
             }
         } completionBlock:^{
+            NSDictionary *info = @{PostPathUserInfoKey : post.path, PostUserInfoKey : post};
+            [[NSNotificationCenter defaultCenter] postNotificationName:DraftAddedNotification object:self userInfo:info];
             fulfill(post);
         }];
     }];
 }
 
-- (PMKPromise *)removeDraftWithPath:(NSString *)path {
+- (PMKPromise *)removeDraft:(Post *)post {
     return [PMKPromise new:^(PMKPromiseFulfiller fulfill, PMKPromiseRejecter reject) {
         [_connection asyncReadWriteWithBlock:^(YapDatabaseReadWriteTransaction *transaction) {
             NSMutableArray *postPaths = [[transaction objectForKey:@"drafts" inCollection:@"PostCollection"] mutableCopy];
-            if ([postPaths containsObject:path]) {
+            if ([postPaths containsObject:post.path]) {
-                [postPaths removeObject:path];
+                [postPaths removeObject:post.path];
                 [transaction setObject:postPaths forKey:@"drafts" inCollection:@"PostCollection"];
             }
         } completionBlock:^{
-            fulfill(path);
+            NSDictionary *info = @{PostPathUserInfoKey : post.path, PostUserInfoKey : post};
+            [[NSNotificationCenter defaultCenter] postNotificationName:DraftRemovedNotification object:self userInfo:info];
+            fulfill(post);
         }];
     }];
 }
@@ -174,21 +192,25 @@
                 [transaction setObject:postPaths forKey:@"published" inCollection:@"PostCollection"];
             }
         } completionBlock:^{
+            NSDictionary *info = @{PostPathUserInfoKey : post.path, PostUserInfoKey : post};
+            [[NSNotificationCenter defaultCenter] postNotificationName:PublishedPostAddedNotification object:self userInfo:info];
             fulfill(post);
         }];
     }];
 }
 
-- (PMKPromise *)removePostWithPath:(NSString *)path {
+- (PMKPromise *)removePost:(Post *)post {
     return [PMKPromise new:^(PMKPromiseFulfiller fulfill, PMKPromiseRejecter reject) {
         [_connection asyncReadWriteWithBlock:^(YapDatabaseReadWriteTransaction *transaction) {
             NSMutableArray *postPaths = [[transaction objectForKey:@"published" inCollection:@"PostCollection"] mutableCopy];
-            if ([postPaths containsObject:path]) {
+            if ([postPaths containsObject:post.path]) {
-                [postPaths removeObject:path];
+                [postPaths removeObject:post.path];
                 [transaction setObject:postPaths forKey:@"published" inCollection:@"PostCollection"];
             }
         } completionBlock:^{
-            fulfill(path);
+            NSDictionary *info = @{PostPathUserInfoKey : post.path, PostUserInfoKey : post};
+            [[NSNotificationCenter defaultCenter] postNotificationName:PublishedPostRemovedNotification object:self userInfo:info];
+            fulfill(post);
         }];
     }];
 }

Blog/PostsViewController.m

@@ -16,6 +16,7 @@
 #import "NSDate+marshmallows.h"
 #import "UIColor+Hex.h"
 #import "PostCollection.h"
+#import "ModelStore.h"
 
 @interface PostsViewController ()
 
@@ -106,6 +107,7 @@ static const NSUInteger SectionPublished = 1;
 
 - (void)viewWillAppear:(BOOL)animated {
     [super viewWillAppear:animated];
+    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(postUpdated:) name:PostUpdatedNotification object:nil];
     [self setupBlogStatusTimer];
     [self requestStatusWithCaching:YES];
     if (!self.postCollections) {
@@ -115,6 +117,7 @@ static const NSUInteger SectionPublished = 1;
 
 - (void)viewWillDisappear:(BOOL)animated {
     [super viewWillDisappear:animated];
+    [[NSNotificationCenter defaultCenter] removeObserver:self name:PostUpdatedNotification object:nil];
     [self teardownBlogStatusTimer];
 }
 
@@ -211,20 +214,8 @@ static const NSUInteger SectionPublished = 1;
     });
 }
 
-#pragma mark - Segues
+- (void)postUpdated:(NSNotification *)note {
-
+    Post *post = note.userInfo[PostUserInfoKey];
-- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {
-    if ([segue.identifier isEqualToString:@"showDetail"]) {
-        NSIndexPath *indexPath = [self.tableView indexPathForSelectedRow];
-        Post *post = [self postForIndexPath:indexPath];
-        EditorViewController *controller = (EditorViewController *)[[segue destinationViewController] topViewController];
-        controller.blogController = self.blogController;
-        [controller configureWithPost:post];
-        controller.navigationItem.leftBarButtonItem = self.splitViewController.displayModeButtonItem;
-        controller.navigationItem.leftItemsSupplementBackButton = YES;
-        __weak __typeof__(self) welf = self;
-        controller.postUpdatedBlock = ^(Post *post) {
-            __typeof__(self) self = welf;
     BOOL (^isThisPost)(Post *, NSUInteger, BOOL *) = ^BOOL(Post *p, NSUInteger idx, BOOL *stop) {
         return [p.objectID isEqualToString:post.objectID];
     };
@@ -240,7 +231,19 @@ static const NSUInteger SectionPublished = 1;
         NSIndexPath *indexPath = [NSIndexPath indexPathForRow:row inSection:section];
         [self.tableView reloadRowsAtIndexPaths:@[indexPath] withRowAnimation:UITableViewRowAnimationAutomatic];
     }
-        };
+}
+
+#pragma mark - Segues
+
+- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {
+    if ([segue.identifier isEqualToString:@"showDetail"]) {
+        NSIndexPath *indexPath = [self.tableView indexPathForSelectedRow];
+        Post *post = [self postForIndexPath:indexPath];
+        EditorViewController *controller = (EditorViewController *)[[segue destinationViewController] topViewController];
+        controller.blogController = self.blogController;
+        [controller configureWithPost:post];
+        controller.navigationItem.leftBarButtonItem = self.splitViewController.displayModeButtonItem;
+        controller.navigationItem.leftItemsSupplementBackButton = YES;
     }
 }
 
@@ -308,7 +311,7 @@ static NSString *const StateRestorationBlogStatusTextKey = @"blogStatusText";
         PostCollection *collection = [self postCollectionForSection:indexPath.section];
         Post *post = [self postForIndexPath:indexPath];
         // TODO: activity indicator
-        [self.blogController requestDeletePostWithPath:post.path].then(^{
+        [self.blogController requestDeletePost:post].then(^{
             [collection.posts removeObjectAtIndex:indexPath.row];
             [tableView deleteRowsAtIndexPaths:@[indexPath] withRowAnimation:UITableViewRowAnimationFade];
         });