let webcam;

class PagePhotograph extends React.Component {
    constructor(props) {
        super(props);
        this.state = {
            isCameraEnable: false,
            isPhotoReady: false,
            myImage: null,
            loading: false,
        };

        this.refVideo = React.createRef();
        this.refCamvas = React.createRef();
        this.refFileInput = React.createRef();
        this.refVideoContainer = React.createRef();
    }

    goNext = (base64) => {
        this.props.next(base64);
    }
    
    goBack = () => {
        this.props.back();
    }

    onLoadedmetadata = () => {
        const { refVideoContainer, refVideo } = this;
        refVideoContainer.current.style = '';
        refVideo.current.width = refVideo.current.videoWidth;
        refVideo.current.height = refVideo.current.videoHeight;
        refVideo.current.defaultMuted = true;
        refVideo.current.muted = true;
        refVideo.current.play();
        const VIDEO__Width = refVideo.current.videoWidth;
        const VIDEO__Height = refVideo.current.videoHeight;
        console.log('videoContainer', refVideoContainer.current.clientHeight);
        const _scale = refVideoContainer.current.clientHeight / Math.min(VIDEO__Width, VIDEO__Height);
        this.setState({isCameraEnable: true});
        console.log('isCameraEnable',this.state.isCameraEnable);
        $(refVideoContainer.current).css({
            width: VIDEO__Width,
            height: VIDEO__Height,
            top: '50%',
            left: '50%',
            'margin-top': VIDEO__Height * -0.5,
            'margin-left': VIDEO__Width * -0.5,
        });
        gsap.set(refVideoContainer.current, {
            scaleX: _scale,
            scaleY: _scale,
            transformOrigin: 'center center',
        });
    }

    initWebcam = () => {
        const { refVideo, refCamvas } = this;
        this.setState({isCameraEnable: false});
        webcam = new Webcam(refVideo.current, 'user', refCamvas.current);
        webcam
            .start()
            .then(() => {})
            .catch((error) => {
                webcam.stop();
                console.log(error);
                alert('妳的瀏覽器不支援相機哦! 請改用左下方按鍵上傳照片，或設定瀏覽器開啟相機。');
            });
    }

    onSnapshot = () => {
        const { refVideoContainer } = this;
        const { isCameraEnable } = this.state;
        if (!isCameraEnable) {
          return;
        }
        this.setState({loading: true});
        webcam
            .snap()
            .then(async (base64) => {
                this.setState({myImage: base64});
                const image = await ImageLoader(base64);
                const canvas = Image2Canvas(image, window.innerWidth / window.innerHeight * refVideoContainer.current.clientHeight, refVideoContainer.current.clientHeight);
                const detectSrc = canvas.toDataURL('image/jpg', 1.0);
                const detectImage = await ImageLoader(detectSrc);
                detectFace(detectImage).then(() => {
                    this.setState({loading: false});
                    this.goNext(detectSrc);
                }).catch((error) => {
                    this.setState({loading: false});
                    console.log('DetectFace Error\nName:'+error.name+'\nMessage:'+error.message);
                    alert(error.message);
                    this.onRemake();
                });
            })
            .catch((error) => {
                this.setState({loading: false});
                console.log(`Snapshot Error\nName: ${error.name}\nMessage: ${error.message}`);
            });
    }

    flipCamera = () => {
        this.setState({isCameraEnable: false});
        webcam.flip();
        webcam.start();
    }

    onRemake = () => {
        this.setState({myImage: ''});
        this.setState({isPhotoReady: false});
        this.setState({isCameraEnable: false});
        this.initWebcam();
    }

    onFileChange = (event) => {
        const file = event.target.files[0];
        if (file) {
          const reader = new FileReader();
          reader.onload = (e) => {
            const image = new Image();
            image.onload = () => {
                const canvas = document.createElement('canvas');
                canvas.width = image.width < 640 ? image.width : 640;
                canvas.height = (image.height / image.width) * canvas.width;
                const context = canvas.getContext('2d');
                context.drawImage(image, 0, 0, canvas.width, canvas.height);
                const base64 = canvas.toDataURL('image/jpg', 1.0);
                ImageLoader(base64).then((_img) => {
                    this.setState({myImage: base64});
                    this.setState({isPhotoReady: true});
                    this.setState({loading: true});
                    detectFace(_img).then(() => {
                        this.setState({loading: false});
                        this.goNext(base64);
                    }).catch((error) => {
                        this.setState({loading: false});
                        console.log('DetectFace Error\nName:'+error.name+'\nMessage:'+error.message);
                        alert(error.message);
                    });
                });
            };
            image.src = e.target.result;
          };
          reader.readAsDataURL(file);
        } else {
          console.log('failed');
        }
    }

    componentDidMount() {
        this.refVideo.current.addEventListener('loadedmetadata', this.onLoadedmetadata);
        this.initWebcam();
    }
  
    componentWillUnmount() {
        this.refVideo.current.removeEventListener("loadedmetadata", this.onLoadedmetadata);
        if (webcam) {
            webcam.stop();
            webcam = null;
        }
    }

    render() {
        const { goBack, onFileChange, onSnapshot, flipCamera, refVideo, refCamvas, refFileInput, refVideoContainer } = this;
        const { isPhotoReady, myImage, isCameraEnable, loading} = this.state;
        return (
            <div class="photographPage">
                <div class="photographPage__header">
                    <div class="btn__back" onClick={goBack}>
                        <img src="https://d1xzlli46wohoc.cloudfront.net/assets/images/btn-back.png" alt="" />
                    </div>
                </div>
                <div class="photographPage__body">
                    <div ref={refVideoContainer} class="video__container">
                        <video ref={refVideo} autoPlay={true} muted playsInline></video>
                        <canvas id='canvas' ref={refCamvas} ></canvas>
                    </div>
                    {
                        (isPhotoReady) ? (
                            <img class="photographPage__userImage" src={myImage} />
                        ) : ('')
                    }
                    <div class="photographPage__facemasker">
                        <img src="https://d1xzlli46wohoc.cloudfront.net/assets/images/masker.png" alt="" />
                        <div class="photographPage__facemaskerText">請在明亮環境，將臉部對準虛線範圍<br/>確保臉部合成準確，請避免頭髮遮蔽五官！</div>
                    </div>
                </div>
                <div class="photographPage__toolbar">
                    <img src="https://d1xzlli46wohoc.cloudfront.net/assets/images/tollbar-bg.png" alt="" />
                    <div class="photographPage__toolbar__wrapper">
                        <div class="btn__insert">
                            <img src="https://d1xzlli46wohoc.cloudfront.net/assets/images/icon-insert-photo.png" alt="" />
                            <input ref={refFileInput} type="file" accept="image/jpg, image/jpeg, image/png" onChange={onFileChange}/>
                        </div>
                        <div className={"btn__camera " + (isCameraEnable ? 'is__show' : 'is__hidden')} onClick={onSnapshot}>
                            <img src="https://d1xzlli46wohoc.cloudfront.net/assets/images/icon-camera.png" alt="" />
                        </div>
                        <div className={"btn__flip__camera "  + (isCameraEnable ? 'is__show' : 'is__hidden')} onClick={flipCamera}>
                            <img src="https://d1xzlli46wohoc.cloudfront.net/assets/images/icon-flip-camera.png" alt="" />
                        </div>
                    </div>
                </div>
                <LoaderComponent show={loading}></LoaderComponent>
            </div>
        );
    }
}