A broken agreement view class that its supposed to interpolate text fields with the form text.

BrokenAgreementView.swift

//
//  AgreementView.swift
//  Intake
//
//  Created by Moshe Berman on 12/11/15.
//  Copyright © 2015 Moshe Berman. All rights reserved.
//

import UIKit

class AgreementView: UITextView, NSLayoutManagerDelegate {
    
    var delimiter = "__x__"
    
    var indices : [NSRange] = []
    var textFields : [AgreementTextField] = []
    var formfields : [FormField] = []
    
    var agreement : Form? {
        didSet {
            
            self.cleanup()
            
            if let agreement = self.agreement {
                
                self.text = agreement.agreementText
                
                self.formfields = agreement.allFields()
                
                self.showTextFields()
            }
        }
    }
    
    override init(frame: CGRect, textContainer: NSTextContainer?) {
        super.init(frame: frame, textContainer: textContainer)
        self.textContainer.layoutManager?.delegate = self
        self.font = UIFont(descriptor: UIFontDescriptor.preferredFontDescriptorWithTextStyle(UIFontTextStyleBody), size: 0)
    }
    
    required init?(coder aDecoder: NSCoder) {
        super.init(coder: aDecoder)
        self.textContainer.layoutManager?.delegate = self
        self.font = UIFont(descriptor: UIFontDescriptor.preferredFontDescriptorWithTextStyle(UIFontTextStyleBody), size: 0)
    }
    
    // MARK: - Show the agreement input fields
    
    func showTextFields() {
        self.calculateTextFieldIndices()
        self.createTextFieldsForFormFields()
        self.createAndAssignExclusionPathsForInputTextFields()
        self.installTextFields()
    }
    
    // MARK: - Form Fields
    
    func createTextFieldsForFormFields () {
        self.textFields = []
        
        var index = 0
        let count = self.formfields.count
        
        while index < count {
            
            let formField = self.formfields[index]
            
            let textField = AgreementTextField(frame: CGRectZero, formField: formField)
            textField.placeholder = formField.displayName
            
            self.textFields.append(textField)
            
            index = index + 1
        }
        
    }
    
    // Calculate where to put the text fields
    func createAndAssignExclusionPathsForInputTextFields () {
        
        var index = 0
        let textFieldCount = self.textFields.count
        
        var exclusionPaths : [UIBezierPath] = []
        
        while index < textFieldCount {
            
            let textField : AgreementTextField = self.textFields[index]
            
            let location = self.calculatePositionOfPlaceholderAtIndex(index)
            let size = textField.intrinsicContentSize()
            textField.frame = CGRectMake(location.x, location.y, size.width, size.height)
            
            exclusionPaths.append(textField.exclusionPath())
            self.textContainer.exclusionPaths = exclusionPaths
            
            self.layoutManager.ensureLayoutForTextContainer(self.textContainer)
            index = index + 1
        }
        
        self.textContainer.exclusionPaths = exclusionPaths
    }
    
    func installTextFields() {
        for field in self.textFields {
            self.addSubview(field)
        }
    }
    
    // MARK: - Helpers
    
    // Find the indices of all of the placeholders.
    func calculateTextFieldIndices () {
        
        var indicesOfDelimiters : [NSRange] = []
        
        let searchString = NSString(string: self.textStorage.string)
        
        var nextDelimiterRange : NSRange = NSMakeRange(0, searchString.length)
        
        while nextDelimiterRange.location != NSNotFound
        {
            nextDelimiterRange = searchString.rangeOfString(self.delimiter, options: [], range: nextDelimiterRange)
            
            if nextDelimiterRange.location != NSNotFound {
                
                let location = nextDelimiterRange.location - (self.delimiter.characters.count * indicesOfDelimiters.count)
                let rangeToAppend = NSMakeRange(location, self.delimiter.characters.count)
                
                indicesOfDelimiters.append(rangeToAppend) // Grab actual location
                
                nextDelimiterRange = NSMakeRange(nextDelimiterRange.location + nextDelimiterRange.length, searchString.length - (nextDelimiterRange.location + nextDelimiterRange.length))
            }
        }
        
        self.indices = indicesOfDelimiters
    }
        
    // Figure out where the text container wanted to put the
    // placeholder glyph and use that to show the text field.
    func calculatePositionOfPlaceholderAtIndex(textIndex : NSInteger) -> CGPoint {
        
        let layoutManager : NSLayoutManager = self.textContainer.layoutManager!
        
        let delimiterRange = self.indices[textIndex]
        let characterIndex = delimiterRange.location
        let glyphRange = self.layoutManager.glyphRangeForCharacterRange(delimiterRange, actualCharacterRange:nil)
        let glyphIndex = glyphRange.location
        let rect = layoutManager.lineFragmentRectForGlyphAtIndex(glyphIndex, effectiveRange: nil, withoutAdditionalLayout: true)
        
        let remainingRect : UnsafeMutablePointer<CGRect> = nil
        
        let textContainerRect = self.textContainer.lineFragmentRectForProposedRect(rect, atIndex: characterIndex, writingDirection: .LeftToRight, remainingRect: remainingRect)
        
        let position = CGPointMake(rect.origin.x, textContainerRect.origin.y)
     
        print("Position: \(position) Character Index: \(characterIndex), Manager Rect: \(rect), Text Container Rect: \(textContainerRect)")
        
        return position
    }    
    // MARK: - Cleanup
    
    func cleanup() {
        
        for textField in self.textFields {
            textField.removeFromSuperview()
        }
        
        self.textFields.removeAll()
        self.indices.removeAll()
    }
}