/*
* The MIT License (MIT)
*
* Copyright (c) 2014 Matt Allen
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in all
* copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
package org.sufficientlysecure.keychain.ui.widget;
import android.content.Context;
import android.content.res.TypedArray;
import android.graphics.Color;
import android.graphics.Paint;
import android.util.AttributeSet;
import android.view.View;
import org.sufficientlysecure.keychain.R;
/**
* Created by Matt Allen
* 01/07/14
* http://www.mattallensoftware.co.uk
* mattallen092@gmail.com
* <p/>
* https://github.com/matt-allen/android-password-strength-indicator
* <p/>
* <p>
* This View is designed to indicate how secure a user-entered password is in a visual way to
* relay to the user if they need to make it stronger. The strength of the password can be set
* at creation (or after) which will decide whether their password is strong enough.
* </p>
* <p/>
* <p>
* The password strength is decided by an index of 20. The minimum score needed to pass is 10
* which means the String has met the conditions imposed by the strength test, but can be improved.
* If the password scores 10-19 it is considered weak, and only if it scores 20 will it be
* considered strong.
* </p>
*/
public class PasswordStrengthView extends View {
protected int mMinWidth;
protected int mMinHeight;
protected Paint mIndicatorPaint;
protected Paint mGuidePaint;
protected int mIndicatorHeight;
protected int mIndicatorWidth;
protected int mCurrentScore;
protected int mColorFail;
protected int mColorWeak;
protected int mColorStrong;
protected boolean mShowGuides = true;
/**
* Used to define that the indicator should only be looking
* for a weak password. The bare minimum is used here to let
* the user continue.
*/
public static final int STRENGTH_WEAK = 0;
/**
* A fairly strict rule for generating a password. It encourages a password that is
* less easy to crack.
*/
public static final int STRENGTH_MEDIUM = 1;
/**
* A strong algorithm that encourages very strong passwords that should be fairly long, with
* non-alphanumeric, numbers, and upper case.
*/
public static final int STRENGTH_STRONG = 2;
private int mStrengthRequirement = -1;
protected String mPassword;
public PasswordStrengthView(Context context, AttributeSet attrs) {
super(context, attrs);
int COLOR_FAIL = getResources().getColor(R.color.android_red_light);
int COLOR_WEAK = getResources().getColor(R.color.android_orange_light);
int COLOR_STRONG = getResources().getColor(R.color.android_green_light);
TypedArray style = context.getTheme().obtainStyledAttributes(
attrs,
R.styleable.PasswordStrengthView,
0, 0);
mStrengthRequirement = style.getInteger(R.styleable.PasswordStrengthView_strength,
STRENGTH_MEDIUM);
mShowGuides = style.getBoolean(R.styleable.PasswordStrengthView_showGuides, true);
mColorFail = style.getColor(R.styleable.PasswordStrengthView_color_fail, COLOR_FAIL);
mColorWeak = style.getColor(R.styleable.PasswordStrengthView_color_weak, COLOR_WEAK);
mColorStrong = style.getColor(R.styleable.PasswordStrengthView_color_strong,
COLOR_STRONG);
// Create and style the paint used for drawing the guide on the indicator
mGuidePaint = new Paint(Paint.ANTI_ALIAS_FLAG);
mGuidePaint.setStyle(Paint.Style.FILL_AND_STROKE);
mGuidePaint.setColor(Color.BLACK);
// Create and style paint for indicator
mIndicatorPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
mIndicatorPaint.setStyle(Paint.Style.FILL);
style.recycle();
}
/**
* This view can determine if the password entered by the user is acceptable for
* use by your use case. This is based on the strength requirement you have set.
*
* @return True if requirement has been met
*/
public boolean isStrengthRequirementMet() {
return (mCurrentScore >= 10);
}
/**
* Change the strength requirement of the password entered by the user. This will also
* re-check the password already entered against these new requirements.
*
* @param requiredStrength Use the public constants of this class to set
*/
public void setStrengthRequirement(int requiredStrength) {
if (requiredStrength >= 0 && requiredStrength <= 2) {
mStrengthRequirement = requiredStrength;
if (mPassword != null && mPassword.length() > 0) {
generatePasswordScore();
// Update view with new score
invalidate();
requestLayout();
}
} else {
throw new IndexOutOfBoundsException("Input out of expected range");
}
}
/**
* Update the password string to check strength of
*
* @param passwordString String representation of user-input
*/
public void setPassword(String passwordString) {
if (passwordString != null && passwordString.length() > 0) {
mPassword = passwordString;
generatePasswordScore();
} else {
mPassword = "";
mCurrentScore = 0;
}
// Update view with new score
invalidate();
requestLayout();
}
/**
* Private convenience method for adding to the password score
*
* @param score Amount to be added to current score
*/
protected void addToPasswordScore(int score) {
int newScore = mCurrentScore + score;
// Limit max score
if (newScore > 20) {
mCurrentScore = 20;
} else {
mCurrentScore = newScore;
}
}
/**
* Call this to determine the current strength requirement set on the algorithm
*
* @return Int representation of the current strength set for the indicator
*/
public int getStrengthRequirement() {
return mStrengthRequirement;
}
/**
* Generate a score based on the password. The password will already need to be stored
* as a class member before running this.
*/
protected void generatePasswordScore() {
mCurrentScore = 0;
int upperCase = getUppercaseCount(mPassword);
int nonAlpha = getNonAlphanumericCount(mPassword);
int numbers = getNumberCount(mPassword);
switch (mStrengthRequirement) {
case STRENGTH_WEAK:
addToPasswordScore(mPassword.length() * 2);
addToPasswordScore(upperCase * 2);
addToPasswordScore(nonAlpha * 2);
addToPasswordScore(numbers * 2);
break;
case STRENGTH_MEDIUM:
addToPasswordScore(mPassword.length());
addToPasswordScore(upperCase);
addToPasswordScore(nonAlpha * 2);
addToPasswordScore(numbers);
break;
case STRENGTH_STRONG:
addToPasswordScore(mPassword.length() / 2);
// Cut the score in half to make this a very high requirement
addToPasswordScore(upperCase);
addToPasswordScore(nonAlpha);
addToPasswordScore(numbers);
break;
}
}
@Override
protected void onSizeChanged(int w, int h, int oldW, int oldH) {
super.onSizeChanged(w, h, oldW, oldH);
int paddingX = getPaddingLeft();
int paddingY = getPaddingTop();
mIndicatorHeight = h - paddingY;
mIndicatorWidth = w - paddingX;
}
/**
* The standard parts of the onMeasure needed to create the password strength
* indicator. Subclasses should call super.onMeasure, but also need to set
* the minimum height and width in the constructor.
*
* @param widthMeasureSpec The measurement given by the system
* @param heightMeasureSpec The measurement given by the system
*/
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
// Set minimum space for the view to do it's thing
int minW = getPaddingLeft() + getPaddingRight() + mMinWidth;
int w = resolveSizeAndState(minW, widthMeasureSpec, 1);
// And give it enough height so it's visible
int minH = mMinHeight + getPaddingBottom() + getPaddingTop();
int h = resolveSizeAndState(minH, heightMeasureSpec, 0);
// Feed these back into UIKit
setMeasuredDimension(w, h);
}
/**
* Set the colour of the indicator {@code Paint} to one that is appropriate
* for the strength of the password.
*/
protected void generateIndicatorColor() {
int color = mColorFail;
if (mCurrentScore >= 18) {
color = mColorStrong;
} else if (mCurrentScore >= 10) {
color = mColorWeak;
}
mIndicatorPaint.setColor(color);
}
/**
* Quick method to determine how many of the characters in a given string are upper case
*
* @param stringToCheck The string to examine
* @return Number of upper case characters
*/
protected int getUppercaseCount(String stringToCheck) {
int score = 0;
int loops = stringToCheck.length() - 1;
for (int i = 0; i <= loops; i++) {
if (Character.isUpperCase(stringToCheck.charAt(i))) {
score++;
}
}
return score;
}
/**
* A convenience method to determine how many characters in the given String aren't
* letters or numbers.
*
* @param stringToCheck
* @return Number of characters that aren't numbers or letters
*/
protected int getNonAlphanumericCount(String stringToCheck) {
int score = 0;
int loops = stringToCheck.length() - 1;
for (int i = 0; i <= loops; i++) {
if (!Character.isLetter(stringToCheck.charAt(i)) &&
!Character.isDigit(stringToCheck.charAt(i))) {
score++;
}
}
return score;
}
/**
* A convenience method for returning the count of numbers in a given String.
*
* @param stringToCheck
* @return The numbers of digits in the String
*/
protected int getNumberCount(String stringToCheck) {
int score = 0;
int loops = stringToCheck.length() - 1;
for (int i = 0; i <= loops; i++) {
if (Character.isDigit(stringToCheck.charAt(i))) {
score++;
}
}
return score;
}
/**
* Set the guides to show on the view.<br />
* On the line style, the guides will show underneath<br />
* On the rounded style, the guides will be shown on the outer edges.<br />
* The view will be redrawn after the method is called.
*
* @param showGuides True if you want the guides to be shown
*/
public void setShowGuides(boolean showGuides) {
mShowGuides = showGuides;
if (mPassword != null && mPassword.length() > 0) {
generatePasswordScore();
} else {
mCurrentScore = 0;
}
invalidate();
requestLayout();
}
/**
* Determine whether the view is showing the guides for the password score
*
* @return True if the guides are being shown
*/
public boolean isShowingGuides() {
return mShowGuides;
}
}