import React,{Component}from 'react';
import {
    View,
    StyleSheet,
    Animated,
    Easing
}from 'react-native';
import PropTypes from "prop-types"
export default class CusProgressBar extends Component {
    static propTypes = {
        ...View.propTypes,
        //当前进度
        progress: PropTypes.number,
        //second progress进度
        buffer: PropTypes.number,
        //进度条颜色
        progressColor: PropTypes.string,
        //buffer进度条颜色
        bufferColor: PropTypes.string,
        //进度动画时长
        progressAniDuration: PropTypes.number,
        //buffer动画时长
        bufferAniDuration: PropTypes.number
    }
    static defaultProps = {
        //进度条颜色
        progressColor: 'red',
        //buffer进度条颜色
        bufferColor: 'rgba(255,0,0,0.7)',
        //进度条动画时长
        progressAniDuration: 300,
        //buffer进度条动画时长
        bufferAniDuration: 300
    }
    // 构造
    constructor(props) {
        super(props);
        this._progressAni = new Animated.Value(0);
        this._bufferAni = new Animated.Value(0);
    }

    componentWillReceiveProps(nextProps) {
        this._progress = nextProps.progress;
        this._buffer = nextProps.buffer;
    }

    componentWillMount() {
        this._progress = this.props.progress;
        this._buffer = this.props.buffer;
    }

    render() {
        return (
            <View
                style={[styles.container,this.props.style]}
                onLayout={this._onLayout.bind(this)}
            >
                <Animated.View
                    ref="progress"
                    style={{
                        position:'absolute',
                        width:this._progressAni,
                        backgroundColor:this.props.progressColor
                    }}
                />
                <Animated.View
                    ref="buffer"
                    style={{
                        position:'absolute',
                        width:this._bufferAni,
                        backgroundColor:this.props.bufferColor
                    }}
                />
            </View>
        );
    }

    _onLayout({nativeEvent:{layout:{width,height}}}) {
        //防止多次调用,当第一次获取后,后面就不再去获取了
        if (width > 0 && this.totalWidth !== width) {
            //获取progress控件引用
            let progress = this._getProgress();
            //获取buffer控件引用
            let buffer = this._getBuffer();
            //获取父布局宽度
            this.totalWidth = width;
            //给progress控件设置高度
            progress.setNativeProps({
                style: {
                    height: height
                }
            });
            //给buffer控件设置高度
            buffer.setNativeProps({
                style: {
                    height: height
                }
            });
            //开始执行进度条动画
            this._startAniProgress(this.progress);
            //开始执行buffer动画
            this._startAniBuffer(this.buffer);
        }
    }

    _startAniProgress(progress) {
        if (this._progress >= 0 && this.totalWidth != 0) {
            Animated.timing(this._progressAni, {
                toValue: progress * this.totalWidth,
                duration: this.props.progressAniDuration,
                easing: Easing.linear
            }).start();
        }
    }

    _startAniBuffer(buffer) {
        if (this._buffer >= 0 && this.totalWidth != 0) {
            Animated.timing(this._bufferAni, {
                toValue: buffer * this.totalWidth,
                duration: this.props.bufferAniDuration,
            }).start();
        }
    }

    _getProgress() {
        if (typeof this.refs.progress.refs.node !== 'undefined') {
            return this.refs.progress.refs.node;
        }
        return this.refs.progress._component;
    }

    _getBuffer() {
        if (typeof this.refs.buffer.refs.node !== 'undefined') {
            return this.refs.buffer.refs.node;
        }
        return this.refs.buffer._component;
    }
}
Object.defineProperty(CusProgressBar.prototype, 'progress', {
    set(value){
        if (value >= 0 && this._progress != value) {
            this._progress = value;
            this._startAniProgress(value);
        }
    },
    get() {
        return this._progress;
    },
    enumerable: true,
});
Object.defineProperty(CusProgressBar.prototype, 'buffer', {
    set(value){
        if (value >= 0 && this._buffer != value) {
            this._buffer = value;
            this._startAniBuffer(value);
        }
    },
    get() {
        return this._buffer;
    },
    enumerable: true,
});
const styles = StyleSheet.create({
    container: {
        height: 4,
        backgroundColor: '#9c9c9c'
    }
});