/*

 * Copyright (C) 2013 Andreas Stuetz <andreas.stuetz@gmail.com>

 *

 * Licensed under the Apache License, Version 2.0 (the "License");

 * you may not use this file except in compliance with the License.

 * You may obtain a copy of the License at

 *

 *      http://www.apache.org/licenses/LICENSE-2.0

 *

 * Unless required by applicable law or agreed to in writing, software

 * distributed under the License is distributed on an "AS IS" BASIS,

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 * See the License for the specific language governing permissions and

 * limitations under the License.

 */

package com.astuetz.viewpager.extensions;

import java.util.Locale;

import android.annotation.SuppressLint;

import android.content.Context;

import android.content.res.TypedArray;

import android.graphics.Canvas;

import android.graphics.Paint;

import android.graphics.Paint.Style;

import android.graphics.Typeface;

import android.os.Build;

import android.os.Parcel;

import android.os.Parcelable;

import android.support.v4.view.ViewPager;

import android.support.v4.view.ViewPager.OnPageChangeListener;

import android.util.AttributeSet;

import android.util.DisplayMetrics;

import android.util.TypedValue;

import android.view.Gravity;

import android.view.View;

import android.view.ViewTreeObserver.OnGlobalLayoutListener;

import android.widget.HorizontalScrollView;

import android.widget.ImageButton;

import android.widget.LinearLayout;

import android.widget.TextView;

import com.beem.project.beem.R;

public class PagerSlidingTabStrip extends HorizontalScrollView {

	public interface IconTabProvider {

		public int getPageIconResId(int position);

	}

	// @formatter:off

	private static final int[] ATTRS = new int[] {

		android.R.attr.textSize,

		android.R.attr.textColor

    };

	// @formatter:on

	private LinearLayout.LayoutParams defaultTabLayoutParams;

	private LinearLayout.LayoutParams expandedTabLayoutParams;

	private final PageListener pageListener = new PageListener();

	public OnPageChangeListener delegatePageListener;

	private LinearLayout tabsContainer;

	private ViewPager pager;

	private int tabCount;

	private int currentPosition = 0;

	private float currentPositionOffset = 0f;

	private Paint rectPaint;

	private Paint dividerPaint;

	private boolean checkedTabWidths = false;

	private int indicatorColor = 0xFF666666;

	private int underlineColor = 0x1A000000;

	private int dividerColor = 0x1A000000;

	private boolean shouldExpand = false;

	private boolean textAllCaps = true;

	private int scrollOffset = 52;

	private int indicatorHeight = 8;

	private int underlineHeight = 2;

	private int dividerPadding = 12;

	private int tabPadding = 24;

	private int dividerWidth = 1;

	private int tabTextSize = 12;

	private int tabTextColor = 0xFF666666;

	private Typeface tabTypeface = null;

	private int tabTypefaceStyle = Typeface.BOLD;

	private int lastScrollX = 0;

	private int tabBackgroundResId = R.drawable.background_tab;

	private Locale locale;

	public PagerSlidingTabStrip(Context context) {

		this(context, null);

	}

	public PagerSlidingTabStrip(Context context, AttributeSet attrs) {

		this(context, attrs, 0);

	}

	public PagerSlidingTabStrip(Context context, AttributeSet attrs, int defStyle) {

		super(context, attrs, defStyle);

		setFillViewport(true);

		setWillNotDraw(false);

		tabsContainer = new LinearLayout(context);

		tabsContainer.setOrientation(LinearLayout.HORIZONTAL);

		tabsContainer.setLayoutParams(new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT));

		addView(tabsContainer);

		DisplayMetrics dm = getResources().getDisplayMetrics();

		scrollOffset = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, scrollOffset, dm);

		indicatorHeight = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, indicatorHeight, dm);

		underlineHeight = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, underlineHeight, dm);

		dividerPadding = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, dividerPadding, dm);

		tabPadding = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, tabPadding, dm);

		dividerWidth = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, dividerWidth, dm);

		tabTextSize = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_SP, tabTextSize, dm);

		// get system attrs (android:textSize and android:textColor)

		TypedArray a = context.obtainStyledAttributes(attrs, ATTRS);

		tabTextSize = a.getDimensionPixelSize(0, tabTextSize);

		tabTextColor = a.getColor(1, tabTextColor);

		a.recycle();

		// get custom attrs

		a = context.obtainStyledAttributes(attrs, R.styleable.PagerSlidingTabStrip);

		indicatorColor = a.getColor(R.styleable.PagerSlidingTabStrip_indicatorColor, indicatorColor);

		underlineColor = a.getColor(R.styleable.PagerSlidingTabStrip_underlineColor, underlineColor);

		dividerColor = a.getColor(R.styleable.PagerSlidingTabStrip_dividerColor, dividerColor);

		indicatorHeight = a.getDimensionPixelSize(R.styleable.PagerSlidingTabStrip_indicatorHeight, indicatorHeight);

		underlineHeight = a.getDimensionPixelSize(R.styleable.PagerSlidingTabStrip_underlineHeight, underlineHeight);

		dividerPadding = a.getDimensionPixelSize(R.styleable.PagerSlidingTabStrip_dividerPadding, dividerPadding);

		tabPadding = a.getDimensionPixelSize(R.styleable.PagerSlidingTabStrip_tabPaddingLeftRight, tabPadding);

		tabBackgroundResId = a.getResourceId(R.styleable.PagerSlidingTabStrip_tabBackground, tabBackgroundResId);

		shouldExpand = a.getBoolean(R.styleable.PagerSlidingTabStrip_shouldExpand, shouldExpand);

		scrollOffset = a.getDimensionPixelSize(R.styleable.PagerSlidingTabStrip_scrollOffset, scrollOffset);

		textAllCaps = a.getBoolean(R.styleable.PagerSlidingTabStrip_textAllCaps, textAllCaps);

		a.recycle();

		rectPaint = new Paint();

		rectPaint.setAntiAlias(true);

		rectPaint.setStyle(Style.FILL);

		dividerPaint = new Paint();

		dividerPaint.setAntiAlias(true);

		dividerPaint.setStrokeWidth(dividerWidth);

		defaultTabLayoutParams = new LinearLayout.LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.MATCH_PARENT);

		expandedTabLayoutParams = new LinearLayout.LayoutParams(0, LayoutParams.MATCH_PARENT, 1.0f);

		if (locale == null) {

			locale = getResources().getConfiguration().locale;

		}

	}

	public void setViewPager(ViewPager pager) {

		this.pager = pager;

		if (pager.getAdapter() == null) {

			throw new IllegalStateException("ViewPager does not have adapter instance.");

		}

		pager.setOnPageChangeListener(pageListener);

		notifyDataSetChanged();

	}

	public void setOnPageChangeListener(OnPageChangeListener listener) {

		this.delegatePageListener = listener;

	}

	public void notifyDataSetChanged() {

		tabsContainer.removeAllViews();

		tabCount = pager.getAdapter().getCount();

		for (int i = 0; i < tabCount; i++) {

			if (pager.getAdapter() instanceof IconTabProvider) {

				addIconTab(i, ((IconTabProvider) pager.getAdapter()).getPageIconResId(i));

			} else {

				addTextTab(i, pager.getAdapter().getPageTitle(i).toString());

			}

		}

		updateTabStyles();

		checkedTabWidths = false;

		getViewTreeObserver().addOnGlobalLayoutListener(new OnGlobalLayoutListener() {

			@SuppressWarnings("deprecation")

			@SuppressLint("NewApi")

			@Override

			public void onGlobalLayout() {

				if (Build.VERSION.SDK_INT < Build.VERSION_CODES.JELLY_BEAN) {

					getViewTreeObserver().removeGlobalOnLayoutListener(this);

				} else {

					getViewTreeObserver().removeOnGlobalLayoutListener(this);

				}

				currentPosition = pager.getCurrentItem();

				scrollToChild(currentPosition, 0);

			}

		});

	}

	private void addTextTab(final int position, String title) {

		TextView tab = new TextView(getContext());

		tab.setText(title);

		tab.setFocusable(true);

		tab.setGravity(Gravity.CENTER);

		tab.setSingleLine();

		tab.setOnClickListener(new OnClickListener() {

			@Override

			public void onClick(View v) {

				pager.setCurrentItem(position);

			}

		});

		tabsContainer.addView(tab);

	}

	private void addIconTab(final int position, int resId) {

		ImageButton tab = new ImageButton(getContext());

		tab.setFocusable(true);

		tab.setImageResource(resId);

		tab.setOnClickListener(new OnClickListener() {

			@Override

			public void onClick(View v) {

				pager.setCurrentItem(position);

			}

		});

		tabsContainer.addView(tab);

	}

	private void updateTabStyles() {

		for (int i = 0; i < tabCount; i++) {

			View v = tabsContainer.getChildAt(i);

			v.setLayoutParams(defaultTabLayoutParams);

			v.setBackgroundResource(tabBackgroundResId);

			if (shouldExpand) {

				v.setPadding(0, 0, 0, 0);

			} else {

				v.setPadding(tabPadding, 0, tabPadding, 0);

			}

			if (v instanceof TextView) {

				TextView tab = (TextView) v;

				tab.setTextSize(TypedValue.COMPLEX_UNIT_PX, tabTextSize);

				tab.setTypeface(tabTypeface, tabTypefaceStyle);

				tab.setTextColor(tabTextColor);

				// setAllCaps() is only available from API 14, so the upper case is made manually if we are on a

				// pre-ICS-build

				if (textAllCaps) {

					if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.ICE_CREAM_SANDWICH) {

						tab.setAllCaps(true);

					} else {

						tab.setText(tab.getText().toString().toUpperCase(locale));

					}

				}

			}

		}

	}

	@Override

	protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {

		super.onMeasure(widthMeasureSpec, heightMeasureSpec);

		if (!shouldExpand || MeasureSpec.getMode(widthMeasureSpec) == MeasureSpec.UNSPECIFIED) {

			return;

		}

		int myWidth = getMeasuredWidth();

		int childWidth = 0;

		for (int i = 0; i < tabCount; i++) {

			childWidth += tabsContainer.getChildAt(i).getMeasuredWidth();

		}

		if (!checkedTabWidths && childWidth > 0 && myWidth > 0) {

			if (childWidth <= myWidth) {

				for (int i = 0; i < tabCount; i++) {

					tabsContainer.getChildAt(i).setLayoutParams(expandedTabLayoutParams);

				}

			}

			checkedTabWidths = true;

		}

	}

	private void scrollToChild(int position, int offset) {

		if (tabCount == 0) {

			return;

		}

		int newScrollX = tabsContainer.getChildAt(position).getLeft() + offset;

		if (position > 0 || offset > 0) {

			newScrollX -= scrollOffset;

		}

		if (newScrollX != lastScrollX) {

			lastScrollX = newScrollX;

			scrollTo(newScrollX, 0);

		}

	}

	@Override

	protected void onDraw(Canvas canvas) {

		super.onDraw(canvas);

		if (isInEditMode() || tabCount == 0) {

			return;

		}

		final int height = getHeight();

		// draw indicator line

		rectPaint.setColor(indicatorColor);

		// default: line below current tab

		View currentTab = tabsContainer.getChildAt(currentPosition);

		float lineLeft = currentTab.getLeft();

		float lineRight = currentTab.getRight();

		// if there is an offset, start interpolating left and right coordinates between current and next tab

		if (currentPositionOffset > 0f && currentPosition < tabCount - 1) {

			View nextTab = tabsContainer.getChildAt(currentPosition + 1);

			final float nextTabLeft = nextTab.getLeft();