/*

File: NewsReaderApp.m

Abstract: Use the PubSub framework to create a simple RSS news reader.

Version: 1.0

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*/

#import "NewsReaderApp.h"

#import "FeedListController.h"

#import "EntryListController.h"

#import "EntryController.h"

#import "FeedPicker.h"

#import "ContentFormatting.h"

#import <PubSub/PubSub.h>

NewsReaderApp *gApp;

@implementation NewsReaderApp

+ (void) initialize

{

    [ShortDateTimeTransformer class];   // Register transformers

    [ErrorTransformer class];

    [ArrayTransformer class];

    [PSContentTransformer class];

}

- (void) awakeFromNib

{

    gApp = self;

    [_feedPicker setTarget: self action: @selector(feedPicked:)];

    [_hSplitter setAutosaveName: @"horiz"];

    [_vSplitter setAutosaveName: @"vert"];

}

// NSApplication delegate method called when the application has finished launching

- (void)applicationDidFinishLaunching:(NSNotification *)notification

{

    // Retain our PSClient, so that we can message it later

    _client = [PSClient applicationClient];

    if( ! _client )

        [self fatalError: @"Couldn't get PSClient!"];

    // Set ourselves as the PSClient delegate

    [_client setDelegate: self];

    // Tell the FeedListController about our PSClient

    [_feedListController setPSClient: _client];

    // Ensure that our preferences panel will appear onscreen, and that

    // its values will be up-to-date (in case any other application changed

    // our client's settings).

    [[_refreshIntervalPopUp window] center];

    [self _updatePreferencesPanel];

}

// NSApplication delegate method called when the application has activated

- (void)applicationDidActivate:(NSNotification *)notification

{

    // Again, just make sure that our notion of our settings are up-to-date. (See

    // note above as to why they can get out-dated.)

    [self _updatePreferencesPanel];

}

// Bad things can happen; this is the unpredictable Internet, after all!

// Displays an alert panel, and quits the application.

- (void) fatalError: (NSString*)message

{

    NSRunCriticalAlertPanel(@"Fatal Error!",

                            @"Sorry, NewsReader is not going to work: %@",

                            @"Quit",nil,nil,

                            message);

    exit(1);

}

// Returns the EntryListController for the input PSFeed. Returns nil if the input

// feed is not the our EntryListController's currentFeed.

- (EntryListController*) entryControllerForFeed: (PSFeed*)feed

{

    if( feed == _entryListController.currentFeed )

        return _entryListController;

    else

        return nil;

}

// Updates the EntryListController's notion of the current (selected) feed.

- (void) setSelectedFeed: (PSFeed*)feed

{

    if( feed != _selectedFeed ) {

        _selectedFeed = feed;

        _entryListController.currentFeed = feed;

    }

}

// Updates the EntryController's notion of the current (selected) entry.

- (void) setSelectedEntry: (PSEntry*)entry

{

    if( entry != _selectedEntry ) {

        _selectedEntry = entry;

        [_entryController setCurrentEntry: entry];

    }

}

// The currently selected feed

- (PSFeed*) selectedFeed

{

    return _selectedFeed;

}

// The currently selected entry

- (PSEntry*) selectedEntry

{

    return _selectedEntry;

}

#pragma mark -

#pragma mark PREFS:

// This method takes the input NSTimeInterval, and translates it into a value in one of

// our preferences popups, selecting the item assumed to have that value in the popup.

// See note below about the assumptions made regarding popup items and their values.

- (void) _setTimeInterval: (NSTimeInterval)interval ofPrefsPopUp: (NSPopUpButton*)popUp

{

    // Assumes items are in increasing time order, and last two are separator and "Never"

    NSMenuItem *selItem = nil;

    // A negative interval is a semaphore indicating "Never"

    if( interval < 0 ) {

        selItem = [popUp lastItem];

    } else {

        // Iterate through the items in the popup

        for( NSMenuItem *item in [popUp itemArray] ) {

            // Bypass separator items

            if( [item isSeparatorItem] )

                break;

            else {

                selItem = item;

                // We've got a "match" with the first item whose tag is greater than or

                // equal to our input interval

                if( [item tag] >= interval )

                    break;

            }

        }

    }

    // Change the popup's selected item to our newly identified one

    [popUp selectItem: selItem];

}

// Using our PSClient's settings, set our refreshInterval and expirationInterval

// popups in our preferences panel.

- (void) _updatePreferencesPanel

{

    PSFeedSettings *settings = [_client settings];

    NSAssert(settings!=nil,@"Couldn't get client settings");

    [self _setTimeInterval: [settings refreshInterval] 

              ofPrefsPopUp: _refreshIntervalPopUp];

    [self _setTimeInterval: [settings expirationInterval]

              ofPrefsPopUp: _expirationIntervalPopUp];

}

// Adjust the stored value for refreshInterval or expiration Interval, 

// in our PSClient's settings, according to the selection in the sender

// popup.

- (IBAction) changeIntervalPref: (id)sender

{

    PSFeedSettings *settings = [_client settings];

    NSAssert(settings!=nil,@"Couldn't get client settings");

    NSTimeInterval interval = [[sender selectedItem] tag];

    if( sender == _refreshIntervalPopUp ) {

        [settings setRefreshInterval: interval];

    } else {

        [settings setExpirationInterval: interval];

    }

    [_client setSettings: settings];

    // Changing the expiration interval affects the entries shown in the list:

    if( sender == _expirationIntervalPopUp )

        [_entryListController reloadEntries];

}

#pragma mark -

#pragma mark PSCLIENT DELEGATE:

// Called by PSClient when one or more entries in a feed have been updated

- (void) feed:(PSFeed *)feed didUpdateEntries:(NSArray *)entries

{

    // If the entry being displayed is updated, reload it

    if( [entries containsObject: [_entryController currentEntry]] )

        [_entryController reload];

}

#pragma mark -

#pragma mark ACTIONS:

// Most of the menu commands are implemented here, rather than in one of the controller

// classes, so that they'll always be enabled regardless of which view has focus.

// (The application delegate is always in the responder chain, while the other views'

// controllers only are while their view is the first responder.)

// Request an update the selected feed immediately

- (IBAction) updateNow: (id)sender

{

    PSFeed *sel = [self selectedFeed];

    if( sel ) {

        NSError *error = nil;

        if( [sel refresh: &error] )

            return; // success

        else

            NSLog(@"Couldn't refresh %@: %@",sel,error);

    }

    NSBeep();

}

// Feed Picker got a feed.

- (IBAction) feedPicked: (id)sender

{

    NSURL *url = ((FeedPicker*)sender).selectedFeedURL;

    NSLog(@"Feed picked: <%@>",url);

    if( url )

        if( ! [_feedListController addFeedWithURL: url] )

            NSBeep();

}

// Remove selected feed from the client

- (IBAction) unsubscribe: (id)sender

{

    [_feedListController delete: self];

}

// Change read/unread status of the selected entry

- (IBAction) toggleUnread: (id)sender

{

    PSEntry *entry = [self selectedEntry];

    if( entry )

        [entry setRead: ![entry isRead]];

    else

        NSBeep();

}

// Change flagged/unflagged status of the selected entry

- (IBAction) toggleFlagged: (id)sender

{

    PSEntry *entry = [self selectedEntry];

    if( entry )

        [entry setFlagged: ![entry isFlagged]];

    else

        NSBeep();

}

// Change read/unread status of all entries in the selected feed

- (IBAction) toggleAllUnread: (id)sender;

{

    PSFeed *sel = [self selectedFeed];

    if( ! sel ) {

        NSBeep();

        return;

    }

    NSArray *entries = [sel entries];

    unsigned n = [entries count];

    for( unsigned i=0; i<n; i++ )

        [[entries objectAtIndex: i] setRead: YES];

}

// Open the current entry's alternateURL in the user's default web browser

// Dispatches to the EntryListController

-  (IBAction) openEntryInBrowser: (id)sender

{

    [_entryListController openEntryInBrowser: sender];

}

// Gives us the opportunity to enable/disable user interface items, according to

// our knowledge of what their state should be. We also use this to change

// the title of menu items (e.g. read to unread, flagged to unflagged, etc.).

- (BOOL) validateUserInterfaceItem: (id<NSValidatedUserInterfaceItem>)item

{

    SEL action = [item action];

    // Only enable user interface items with the updateNow: and unsubscribe: actions

    // if we have a selected feed to act upon

    if( action==@selector(updateNow:) || action==@selector(unsubscribe:) )

        return [self selectedFeed]!=nil;

    // Similarly, only enable the ability to toggleUnread: and toggleFlagged: if we 

    // have a selected entry

    else if( action==@selector(toggleUnread:) || action==@selector(toggleFlagged:) ) {

        PSEntry *entry = [self selectedEntry];

        if( ! entry )

            return NO;

        // Check the selected entry's current read or flagged state, and update

        // the user interface item's title as appropriate (to a string that would

        // indicate a change in state)

        NSString *title;

        if( action==@selector(toggleUnread:) )

            title = ([entry isRead] ?@"Mark As Unread" :@"Mark As Read");

        else

            title = ([entry isFlagged] ?@"Mark As Unflagged" :@"Mark As Flagged");

        [(NSMenuItem*)item setTitle: title];

        return YES;

    } 

    // Only enable user interface items with the openEntryInBrowser: action if the 

    // selected entry has an alternateURL (which is used as the url to open)

    else if( action==@selector(openEntryInBrowser:) )

        return [[self selectedEntry] alternateURL] != nil;

    else

        return YES;

}

@end