package com.uiuios.aios.view;


import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Rect;
import android.os.Build;

import android.util.AttributeSet;

public class RulerSeekBar extends androidx.appcompat.widget.AppCompatSeekBar {

    /**
     * 刻度线画笔
     */
    private Paint mRulerPaint;

    /**
     * 刻度线的个数,等分数等于刻度线的个数加1
     */
    private int mRulerCount = 1;

    /**
     * 每条刻度线的宽度
     */
    private int mRulerWidth = 2;

    /**
     * 刻度线的颜色
     */
    private int mRulerColor = Color.WHITE;

    /**
     * 滑块上面是否要显示刻度线
     */
    private boolean isShowTopOfThumb = false;

    public RulerSeekBar(Context context) {
        super(context);
        init();
    }

    public RulerSeekBar(Context context, AttributeSet attrs) {
        super(context, attrs);
        init();
    }

    public RulerSeekBar(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
        init();
    }

    /**
     * 初始化
     */
    private void init() {
        //创建绘制刻度线的画笔
        mRulerPaint = new Paint();
        mRulerPaint.setColor(mRulerColor);
        mRulerPaint.setAntiAlias(true);

        //Api21及以上调用，去掉滑块后面的背景
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
            setSplitTrack(false);
        }
    }

    /**
     * 重写onDraw方法绘制刻度线
     *
     * @param canvas
     */
    @Override
    protected synchronized void onDraw(Canvas canvas) {
        super.onDraw(canvas);

        //极限条件校验
        if (getWidth() <= 0 || mRulerCount <= 0) {
            return;
        }

        //获取每一份的长度
        int length = (getWidth() - getPaddingLeft() - getPaddingRight() - mRulerCount * mRulerWidth) / (mRulerCount + 1);

        //计算刻度线的顶部坐标和底部坐标
        int rulerTop = getHeight() / 2 - getMinimumHeight() / 2;
        int rulerBottom = rulerTop + getMinimumHeight();

        //获取滑块的位置信息
        Rect thumbRect = null;
        if (getThumb() != null) {
            thumbRect = getThumb().getBounds();
        }

        //绘制刻度线
        for (int i = 1; i <= mRulerCount; i++) {
            //计算刻度线的左边坐标和右边坐标
            int rulerLeft = i * length + getPaddingLeft();
            int rulerRight = rulerLeft + mRulerWidth;

            //判断是否需要绘制刻度线
            if (!isShowTopOfThumb && thumbRect != null && rulerLeft - getPaddingLeft() > thumbRect.left && rulerRight - getPaddingLeft() < thumbRect.right) {
                continue;
            }

            //进行绘制
            canvas.drawRect(rulerLeft, rulerTop, rulerRight, rulerBottom, mRulerPaint);
        }
    }

    /**
     * 设置刻度线的个数
     *
     * @param mRulerCount
     */
    public void setRulerCount(int mRulerCount) {
        this.mRulerCount = mRulerCount;
        requestLayout();
    }

    /**
     * 设置刻度线的宽度，单位(px)
     *
     * @param mRulerWidth
     */
    public void setRulerWidth(int mRulerWidth) {
        this.mRulerWidth = mRulerWidth;
        requestLayout();
    }

    /**
     * 设置刻度线的颜色
     *
     * @param mRulerColor
     */
    public void setRulerColor(int mRulerColor) {
        this.mRulerColor = mRulerColor;
        if (mRulerPaint != null) {
            mRulerPaint.setColor(mRulerColor);
            requestLayout();
        }
    }

    /**
     * 滑块上面是否需要显示刻度线
     *
     * @param isShowTopOfThumb
     */
    public void setShowTopOfThumb(boolean isShowTopOfThumb) {
        this.isShowTopOfThumb = isShowTopOfThumb;
        requestLayout();
    }
}