/*

 Copyright (C) 2016 Apple Inc. All Rights Reserved.

 See LICENSE.txt for this sample’s licensing information

 Abstract:

 Application Controller object, and the NSBrowser delegate. An instance of this object is in the MainMenu.xib.

 */

#import "AppController.h"

#import "FileSystemNode.h"

#import "FileSystemBrowserCell.h"

#import "PreviewViewController.h"

@interface AppController ()

// please note bug #24527817

// NSBrowser column titles draw sporadic when navigating back with left arrow key (10.11)

//

@property (weak) IBOutlet NSBrowser *browser;

@property (strong) FileSystemNode *rootNode;

@property NSInteger draggedColumnIndex;

@property (strong) PreviewViewController *sharedPreviewController;

@property (weak) IBOutlet NSWindow *window;

@end

#pragma mark -

@implementation AppController

- (void)awakeFromNib {

    // use a custom cell class for each browser item

    [self.browser setCellClass:[FileSystemBrowserCell class]];

    // Drag and drop support

    [self.browser registerForDraggedTypes:@[NSFilenamesPboardType]];

    [self.browser setDraggingSourceOperationMask:NSDragOperationEvery forLocal:YES];

    [self.browser setDraggingSourceOperationMask:NSDragOperationEvery forLocal:NO];

    // if you want to change the background color of NSBrowser use this:

    //self.browser.backgroundColor = [NSColor controlBackgroundColor];

    // Double click support

    self.browser.target = self;

    self.browser.doubleAction = @selector(browserDoubleClick:);

}

- (id)rootItemForBrowser:(NSBrowser *)browser {

    if (self.rootNode == nil) {

        _rootNode = [[FileSystemNode alloc] initWithURL:[NSURL fileURLWithPath:NSOpenStepRootDirectory()]];

    }

    return self.rootNode;

}

#pragma mark - NSBrowserDelegate

// Required delegate methods

- (NSInteger)browser:(NSBrowser *)browser numberOfChildrenOfItem:(id)item {

    FileSystemNode *node = (FileSystemNode *)item;

    return node.children.count;

}

- (id)browser:(NSBrowser *)browser child:(NSInteger)index ofItem:(id)item {

    FileSystemNode *node = (FileSystemNode *)item;

    return (node.children)[index];

}

- (BOOL)browser:(NSBrowser *)browser isLeafItem:(id)item {

    FileSystemNode *node = (FileSystemNode *)item;

    return !node.isDirectory || node.isPackage; // take into account packaged apps and documents

}

- (id)browser:(NSBrowser *)browser objectValueForItem:(id)item {

    FileSystemNode *node = (FileSystemNode *)item;

    return node.displayName;

}

- (void)browser:(NSBrowser *)browser willDisplayCell:(FileSystemBrowserCell *)cell atRow:(NSInteger)row column:(NSInteger)column {

    // Find the item and set the image.

    NSIndexPath *indexPath = [browser indexPathForColumn:column];

    indexPath = [indexPath indexPathByAddingIndex:row];

    FileSystemNode *node = [browser itemAtIndexPath:indexPath];

    cell.image = node.icon;

    cell.labelColor = node.labelColor;

}

- (NSViewController *)browser:(NSBrowser *)browser previewViewControllerForLeafItem:(id)item {

    if (self.sharedPreviewController == nil) {

        _sharedPreviewController = [[PreviewViewController alloc] initWithNibName:@"PreviewView" bundle:[NSBundle bundleForClass:[self class]]];

    }

    return self.sharedPreviewController; // NSBrowser will set the representedObject for us

}

- (NSViewController *)browser:(NSBrowser *)browser headerViewControllerForItem:(id)item {

    // Add a header for the first column, just as an example

    if (self.rootNode == item) {

        return [[NSViewController alloc] initWithNibName:@"HeaderView" bundle:[NSBundle bundleForClass:[self class]]];

    } else {

        return nil;

    }

}

- (CGFloat)browser:(NSBrowser *)browser shouldSizeColumn:(NSInteger)columnIndex forUserResize:(BOOL)forUserResize toWidth:(CGFloat)suggestedWidth  {

    if (!forUserResize) {

        id item = [browser parentForItemsInColumn:columnIndex]; 

        if ([self browser:browser isLeafItem:item]) {

            suggestedWidth = 200; 

        }

    }

    return suggestedWidth;

}

#pragma mark - Dragging Source

- (BOOL)browser:(NSBrowser *)browser writeRowsWithIndexes:(NSIndexSet *)rowIndexes inColumn:(NSInteger)column toPasteboard:(NSPasteboard *)pasteboard {

    NSMutableArray *filenames = [NSMutableArray arrayWithCapacity:rowIndexes.count];

    NSIndexPath *baseIndexPath = [browser indexPathForColumn:column]; 

    for (NSUInteger i = rowIndexes.firstIndex; i <= rowIndexes.lastIndex; i = [rowIndexes indexGreaterThanIndex:i]) {

        FileSystemNode *fileSystemNode = [browser itemAtIndexPath:[baseIndexPath indexPathByAddingIndex:i]]; 

        [filenames addObject:(fileSystemNode.URL).path];

    }

    [pasteboard declareTypes:@[NSFilenamesPboardType] owner:self];

    [pasteboard setPropertyList:filenames forType:NSFilenamesPboardType];

    _draggedColumnIndex = column;

    return YES;

}

- (BOOL)browser:(NSBrowser *)browser canDragRowsWithIndexes:(NSIndexSet *)rowIndexes inColumn:(NSInteger)column withEvent:(NSEvent *)event {

    // We will allow dragging any cell - even disabled ones. By default, NSBrowser will not let you drag a disabled cell

    return YES;

}

- (NSImage *)browser:(NSBrowser *)browser draggingImageForRowsWithIndexes:(NSIndexSet *)rowIndexes inColumn:(NSInteger)column withEvent:(NSEvent *)event offset:(NSPointPointer)dragImageOffset {

    NSImage *result = [browser draggingImageForRowsWithIndexes:rowIndexes inColumn:column withEvent:event offset:dragImageOffset];

    // Create a custom drag image "badge" that displays the number of items being dragged

    if (rowIndexes.count > 1) {

        NSString *str = [NSString stringWithFormat:@"%ld items being dragged", (long)rowIndexes.count];

        NSShadow *shadow = [[NSShadow alloc] init];

        shadow.shadowOffset = NSMakeSize(0.5, 0.5);

        shadow.shadowBlurRadius = 5.0;

        shadow.shadowColor = [NSColor blackColor];

        NSDictionary *attrs = @{NSShadowAttributeName: shadow, 

                               NSForegroundColorAttributeName: [NSColor whiteColor]};

        NSAttributedString *countString = [[NSAttributedString alloc] initWithString:str attributes:attrs];

        NSSize stringSize = [countString size];

        NSSize imageSize = result.size;

        imageSize.height += stringSize.height;

        imageSize.width = MAX(stringSize.width + 3, imageSize.width);

        NSImage *newResult = [[NSImage alloc] initWithSize:imageSize];

        [newResult lockFocus];

        [result drawAtPoint:NSMakePoint(0, 0) fromRect:NSZeroRect operation:NSCompositeSourceOver fraction:1.0];

        [countString drawAtPoint:NSMakePoint(0, imageSize.height - stringSize.height)];

        [newResult unlockFocus];

        dragImageOffset->y += (stringSize.height / 2.0);

        result = newResult;

    }

    return result;

}

#pragma mark - Dragging Destination

- (FileSystemNode *)fileSystemNodeAtRow:(NSInteger)row column:(NSInteger)column {

    if (column >= 0) {

        NSIndexPath *indexPath = [self.browser indexPathForColumn:column];

        if (row >= 0) {

            indexPath = [indexPath indexPathByAddingIndex:row];

        }

        id result = [self.browser itemAtIndexPath:indexPath];

        return (FileSystemNode *)result;

    } else {

        return nil;

    }

}

- (NSDragOperation)browser:(NSBrowser *)browser validateDrop:(id <NSDraggingInfo>)info proposedRow:(NSInteger *)row column:(NSInteger *)column  dropOperation:(NSBrowserDropOperation *)dropOperation {

    NSDragOperation result = NSDragOperationNone;

    // We only accept file types

    if ([[info draggingPasteboard].types indexOfObject:NSFilenamesPboardType] > 0) {

        // For a between drop, we let the user drop "on" the parent item

        if (*dropOperation == NSBrowserDropAbove) {

            *row = -1;

        }

        // Only allow dropping in folders, but don't allow dragging from the same folder into itself, if we are the source

        if (*column != -1) {

            BOOL droppingFromSameFolder = ([info draggingSource] == browser) && (*column == self.draggedColumnIndex);

            if (*row != -1) {

                // If we are dropping on a folder, then we will accept the drop at that row

                FileSystemNode *fileSystemNode = [self fileSystemNodeAtRow:*row column:*column];

                if (fileSystemNode.isDirectory) {

                    // Yup, a good drop

                    result = NSDragOperationEvery;

                } else {

                    // Nope, we can't drop onto a file! We will retarget to the column, if it isn't the same folder.

                    if (!droppingFromSameFolder) {

                        result = NSDragOperationEvery;

                        *row = -1;

                        *dropOperation = NSBrowserDropOn;

                    }

                }

            } else if (!droppingFromSameFolder) {

                result = NSDragOperationEvery;

                *row = -1;

                *dropOperation = NSBrowserDropOn;

            }

        }

    }

    return result;

}

- (BOOL)browser:(NSBrowser *)browser acceptDrop:(id <NSDraggingInfo>)info atRow:(NSInteger)row column:(NSInteger)column dropOperation:(NSBrowserDropOperation)dropOperation {

    NSArray *filenames = [[info draggingPasteboard] propertyListForType:NSFilenamesPboardType];

    // Find the target folder

    FileSystemNode *targetFileSystemNode = nil;

    if ((column != -1) && (filenames != nil)) {

        if (row != -1) {

            FileSystemNode *fileSystemNode = [self fileSystemNodeAtRow:row column:column];

            if (fileSystemNode.isDirectory) {

                targetFileSystemNode = fileSystemNode;

            }

        } else {

            // Grab the parent for the column, which should be a directory

            targetFileSystemNode = (FileSystemNode *)[browser parentForItemsInColumn:column];

        }

    }

    // We now have the target folder, so move things around    

    if (targetFileSystemNode != nil) {

        NSString *targetFolder = targetFileSystemNode.URL.path;

        NSMutableString *prettyNames = nil;

        // Create a display name of all the selected filenames that are moving

        for (NSUInteger i = 0; i < filenames.count; i++) {

            NSString *filename = [[NSFileManager defaultManager] displayNameAtPath:filenames[i]];

            if (prettyNames == nil) {

                prettyNames = [filename mutableCopy];                

            } else {

                [prettyNames appendString:@", "];

                [prettyNames appendString:filename];

            }

        }

        // Ask the user if they really want to move those files

        NSAlert *warningAlert = [[NSAlert alloc] init];

        warningAlert.messageText = @"Verify file move";

        warningAlert.informativeText = [NSString stringWithFormat:@"Are you sure you want to move '%@' to '%@'?", prettyNames, targetFolder];

        [warningAlert addButtonWithTitle:@"Yes"];

        [warningAlert addButtonWithTitle:@"No"];

        [warningAlert beginSheetModalForWindow:self.window completionHandler:^(NSInteger result) {

            if (result == NSAlertFirstButtonReturn) {

                // Do the actual moving of the files.

                for (NSUInteger i = 0; i < filenames.count; i++) {

                    NSString *filename = filenames[i];

                    NSString *targetPath = [targetFolder stringByAppendingPathComponent:filename.lastPathComponent];

                    // Normally, you should check the result of movePath to see if it worked or not.

                    NSError *error = nil;

                    if (![[NSFileManager defaultManager] moveItemAtPath:filename toPath:targetPath error:&error] && error) {

                        [NSApp presentError:error];

                        break;

                    }

                }

                // It would be more efficient to invalidate the children of the "from" and "to" nodes and then

                // call -reloadColumn: on each of the corresponding columns. However, we just reload every column

                //

                [self.rootNode invalidateChildren];

                for (NSInteger col = self.browser.lastColumn; col >= 0; col--) {

                    [self.browser reloadColumn:col];

                }

            }

        }];

        return YES;

    }

    return NO;

}

#pragma mark - Action

- (void)browserDoubleClick:(id)sender {

    // Find the clicked item and open it in Finder

    FileSystemNode *clickedNode = [self fileSystemNodeAtRow:self.browser.clickedRow column:self.browser.clickedColumn];

    if (clickedNode != nil) {

        [[NSWorkspace sharedWorkspace] openFile:clickedNode.URL.path];

    }

}

@end