//
//  MPTerminalPreferencesViewController.m
//  MacDown
//
//  Created by Niklas Berglund on 2017-01-11.
//  Copyright © 2017 Tzu-ping Chung . All rights reserved.
//

#import "MPGlobals.h"
#import "MPHomebrewSubprocessController.h"
#import "MPPreferences.h"
#import "MPTerminalPreferencesViewController.h"
#import "MPUtilities.h"


NS_INLINE NSColor *MPGetInstallationIndicatorColor(BOOL installed)
{
    static NSColor *installedColor = nil;
    static NSColor *uninstalledColor = nil;
    static dispatch_once_t onceToken;
    dispatch_once(&onceToken, ^{
        installedColor = [NSColor colorWithDeviceRed:0.357 green:0.659
                                                blue:0.192 alpha:1.000];
        uninstalledColor = [NSColor colorWithDeviceRed:0.897 green:0.231
                                                  blue:0.21 alpha:1.000];
    });
    if (installed)
        return installedColor;
    else
        return uninstalledColor;
}


@interface MPTerminalPreferencesViewController ()

@property (weak) IBOutlet NSTextField *supportIndicator;
@property (weak) IBOutlet NSTextField *supportTextField;
@property (weak) IBOutlet NSTextField *infoTextField;
@property (weak) IBOutlet NSTextField *locationTextField;
@property (weak) IBOutlet NSButton *installUninstallButton;

@property (nonatomic) NSURL *shellUtilityURL;

@end

@implementation MPTerminalPreferencesViewController


#pragma mark - Accessors.

- (void)setShellUtilityURL:(NSURL *)url
{
    _shellUtilityURL = url;
    if (url)
    {
        self.supportIndicator.textColor = MPGetInstallationIndicatorColor(YES);
        self.supportTextField.stringValue = NSLocalizedString(
            @"Shell utility installed",
            @"Label stating that shell utility has been installed");
        self.locationTextField.stringValue = url.path;
        self.locationTextField.font =
            [NSFont fontWithName:@"Menlo"
                            size:self.locationTextField.font.pointSize];
        self.installUninstallButton.title = NSLocalizedString(
            @"Uninstall", @"Uninstall shell utility button");
        self.installUninstallButton.action = @selector(uninstallShellUtility);
    }
    else
    {
        self.supportIndicator.textColor = MPGetInstallationIndicatorColor(NO);
        self.supportTextField.stringValue = NSLocalizedString(
            @"Shell utility not installed",
            @"Label stating that shell utility has not been installed");
        self.locationTextField.stringValue = NSLocalizedString(
            @"<Not installed>",
            @"Displayed when shell utility is not installed");

        NSFont *font =
            [NSFont systemFontOfSize:self.locationTextField.font.pointSize];
        self.locationTextField.font =
            [[NSFontManager sharedFontManager] convertFont:font
                                               toHaveTrait:NSFontItalicTrait];
        self.installUninstallButton.title = NSLocalizedString(
            @"Install", @"Install shell utility button");
        self.installUninstallButton.action = @selector(installShellUtility);
    }
}


- (void)viewDidLoad
{
    [super viewDidLoad];
    [self highlightMacdownInInfo];
    
    self.installUninstallButton.target = self;
    self.shellUtilityURL = nil;
}

- (void)viewWillAppear
{
    [self lookForShellUtility];
}

#pragma mark - MASPreferencesViewController

- (NSString *)viewIdentifier
{
    return @"TerminalPreferences";
}

- (NSImage *)toolbarItemImage
{
    return [NSImage imageNamed:@"PreferencesTerminal"];
}

- (NSString *)toolbarItemLabel
{
    return NSLocalizedString(@"Terminal", @"Preference pane title.");
}

#pragma mark - Private methods

/**
 * Searches for the the macdown shell utility and invokes foundShellUtilityAtURL: if found.
 */
- (void)lookForShellUtility
{
    __weak MPTerminalPreferencesViewController *weakSelf = self;
    MPDetectHomebrewPrefixWithCompletionhandler(^(NSString *output) {
        NSString *macdownPath = MPCommandInstallationPath;
        if (output)
        {
            NSCharacterSet *padding =
                [NSCharacterSet whitespaceAndNewlineCharacterSet];
            NSString *prefix = [output stringByTrimmingCharactersInSet:padding];
            macdownPath =
                [prefix stringByAppendingPathComponent:@"bin/macdown"];
        }

        if ([[NSFileManager defaultManager] fileExistsAtPath:macdownPath])
            weakSelf.shellUtilityURL = [NSURL fileURLWithPath:macdownPath];
    });
}

- (void)installShellUtility
{
    // URL for macdown utility in .app bundle
    NSURL *sharedSupportURL = [NSBundle mainBundle].sharedSupportURL;
    NSString *utilityBundlePath =
        [sharedSupportURL URLByAppendingPathComponent:@"bin/macdown"].path;

    NSFileManager *fm = [NSFileManager defaultManager];
    if ([fm fileExistsAtPath:utilityBundlePath])
    {
        BOOL ok = [fm createSymbolicLinkAtPath:MPCommandInstallationPath
                           withDestinationPath:utilityBundlePath error:NULL];
        if (ok)
            [self lookForShellUtility];
        // TODO: Handle install failure.
    }
}

- (void)uninstallShellUtility
{
    NSURL *url = self.shellUtilityURL;
    if (!url)
        return;
    BOOL ok = [[NSFileManager defaultManager] removeItemAtURL:url error:NULL];
    if (ok)
        self.shellUtilityURL = nil;
    // TODO: Handle removal failure.
}

/**
 * Highlights all occurences of "macdown" in the info-text
 */
- (void)highlightMacdownInInfo
{
    NSString *infoString = self.infoTextField.stringValue;
    NSMutableAttributedString *attributedInfoString =
        [[NSMutableAttributedString alloc] initWithString:infoString];
    
    NSRange searchRange = NSMakeRange(0, infoString.length);
    CGFloat infoFontSize = self.infoTextField.font.pointSize;
    NSFont *highlightFont = [NSFont fontWithName:@"Menlo" size:infoFontSize];
    
    while (searchRange.location < infoString.length)
    {
        searchRange.length = infoString.length - searchRange.location;
        NSRange foundRange =
            [infoString rangeOfString:@"macdown"
                              options:NSLiteralSearch range:searchRange];
        
        if (foundRange.location != NSNotFound)
        {
            [attributedInfoString addAttribute:NSFontAttributeName value:highlightFont range:foundRange];
            
            searchRange.location = foundRange.location + foundRange.length;
        }
        else // Found all occurences
        {
            break;
        }
    }

    self.infoTextField.attributedStringValue = attributedInfoString;
}

@end