/*
 *  Copyright (c)  2017.  wugian
 *  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.xgimi.gimicinema.view;

import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.os.Parcel;
import android.os.Parcelable;
import android.util.AttributeSet;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.TextView;

/**
 * TODO 单行文本跑马灯控件
 *
 * @author tianlu
 * @version 1.0
 *          Create At : 2010-2-16 下午09:35:03
 */
public class AutoScrollTextView extends TextView implements OnClickListener {
    public final static String TAG = AutoScrollTextView.class.getSimpleName();

    private float textLength = 0f;//文本长度
    private float viewWidth = 0f;
    private float step = 0f;//文字的横坐标
    private float y = 0f;//文字的纵坐标
    private float temp_view_plus_text_length = 0.0f;//用于计算的临时变量
    private float temp_view_plus_two_text_length = 0.0f;//用于计算的临时变量
    public boolean isStarting = false;//是否开始滚动
    private Paint paint = null;//绘图样式
    private String text = "";//文本内容


    public AutoScrollTextView(Context context) {
        super(context);
        initView();
    }

    public AutoScrollTextView(Context context, AttributeSet attrs) {
        super(context, attrs);
        initView();
    }

    public AutoScrollTextView(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
        initView();
    }

    /**
     * 初始化控件
     */
    private void initView() {
        setOnClickListener(this);
    }

    private boolean isMeasured;

    /**
     * 文本初始化，每次更改文本内容或者文本效果等之后都需要重新初始化一下
     */
    public void init() {
        paint = getPaint();
        paint.setColor(this.getCurrentTextColor());
        text = getText().toString();
        textLength = paint.measureText(text);
        viewWidth = getWidth();
//        step = textLength;
        step = textLength;
        temp_view_plus_text_length = viewWidth + textLength;
        temp_view_plus_two_text_length = viewWidth + textLength * 2;
        y = getTextSize() + getPaddingTop();
    }

    @Override
    public Parcelable onSaveInstanceState() {
        Parcelable superState = super.onSaveInstanceState();
        SavedState ss = new SavedState(superState);

        ss.step = step;
        ss.isStarting = isStarting;

        return ss;
    }

    @Override
    public void onRestoreInstanceState(Parcelable state) {
        if (!(state instanceof SavedState)) {
            super.onRestoreInstanceState(state);
            return;
        }
        SavedState ss = (SavedState) state;
        super.onRestoreInstanceState(ss.getSuperState());

        step = ss.step;
        isStarting = ss.isStarting;
    }

    public static class SavedState extends BaseSavedState {
        public boolean isStarting = false;
        public float step = 0.0f;

        SavedState(Parcelable superState) {
            super(superState);
        }

        @Override
        public void writeToParcel(Parcel out, int flags) {
            super.writeToParcel(out, flags);
            out.writeBooleanArray(new boolean[]{isStarting});
            out.writeFloat(step);
        }


        public static final Parcelable.Creator<SavedState> CREATOR
                = new Parcelable.Creator<SavedState>() {

            public SavedState[] newArray(int size) {
                return new SavedState[size];
            }

            @Override
            public SavedState createFromParcel(Parcel in) {
                return new SavedState(in);
            }
        };

        private SavedState(Parcel in) {
            super(in);
            boolean[] b = null;
            in.readBooleanArray(b);
            if (b != null && b.length > 0)
                isStarting = b[0];
            step = in.readFloat();
        }
    }

    /**
     * 开始滚动
     */
    public void startScroll() {
        isStarting = true;
        invalidate();
    }

    /**
     * 停止滚动
     */
    public void stopScroll() {
        isStarting = false;
        invalidate();
    }

    private static final int SCROLL_SPEED = 4;

    @Override
    public void onDraw(Canvas canvas) {
        if (!isMeasured) {
            init();
            isMeasured = true;
        }
        canvas.drawText(text, temp_view_plus_text_length - step, y, paint);
        if (!isStarting) {
            return;
        }
        step += SCROLL_SPEED;
//        Log.d(TAG, "onDraw: " + step + "," + temp_view_plus_text_length + "," + viewWidth + "," + textLength);
        if (step > temp_view_plus_two_text_length)
            step = textLength;
        invalidate();

    }

    @Override
    public void onClick(View v) {
        if (isStarting)
            stopScroll();
        else
            startScroll();
    }
}