//
//  Soundex.swift
//  DriverLicense
//
//  Created by Kyle Smith on 11/21/15.
//  Copyright © 2015 Kyle Smith. All rights reserved.
//

import Foundation

class Soundex {
    class func key(word: String) -> String {
        let trimmedWord = word.stringByTrimmingCharactersInSet(NSCharacterSet.whitespaceCharacterSet())
        var letterArray = [Character]()

        for character in trimmedWord.characters {
            letterArray.append(character)
        }
        //let letterArray = Array(arrayLiteral: trimmedWord.uppercaseString)

        if (letterArray.count < 1) {
            return ""
        }

        var soundex:[Character] = Array()

        var lastCode: Character?
        for (index, letter) in (letterArray.enumerate()) {
            if (soundex.count >= 3) { break }

            var code: Character

            switch letter {
            case "R":
                code = "6"
            case "M", "N":
                code = "5"
            case "L":
                code = "4"
            case "T", "D":
                code = "3"
            case "C", "S", "K", "G", "J", "Q", "X", "Z":
                code = "2"
            case "B", "P", "F", "V":
                code = "1"
            default:
                code = "0"
            }

            if (index == 0) {
                lastCode = code
                continue
            }

            if (code != "0" && code != lastCode) {
                soundex.append(code)
                lastCode = code
            }
        }

        while (soundex.count < 3) {
            soundex.append("0")
        }

        soundex.insert(letterArray.first!, atIndex: 0)

        return soundex.reduce("") { $0 + String($1) }
    }

    class func word(word: String, soundsLike: String) -> Bool {
        return self.key(word) == self.key(soundsLike)
    }
}