Telereview/code/interface_borne/assets/js/camera_page.js

class CameraPage {
    constructor() {

        this.spinnerWeight = 10;
        this.spinnerColor = "#0F0FFF"

        this.canvas = document.getElementById("overlay-canvas");
        this.ctx = this.canvas.getContext("2d");
        this.video = document.getElementById("camera-video");
        this.width;
        this.height; //calcule automatiquement en fonction de la largeur du flux vidéo
        this.videoWidth;
        this.videoHeight;
        this.streaming = false;
        this.activeEffects = [];
        this.images = {};
        this._startup();
        this._loadImages();
        this._enabled = false;
        this.DOMElement = document.getElementById("camera");
    }

    set enabled(val) {
        this._enabled = val;
        this.DOMElement.style.display = val ? "block" : "none";
        if (val) {
            this._frame();
            this.video.play();
        }else {
            this.video.pause();
        }
    }

    get enabled() {
        return this._enabled;
    }

    _startup() {
        navigator.mediaDevices
            .getUserMedia({ video: true, audio: false })
            .then((stream) => {
                this.video.srcObject = stream;
                this.video.play();
            })
            .catch((err) => {
                console.error(`Erreur pendant la lecture de la camera: ${err}`);
            });

        this.video.addEventListener(
            "canplay",
            (ev) => {
                if (!this.streaming) {
                    //calcul de la taille de la vidéo en fonction de la taille de la fenêtre pour qu'elle soit toujours visible
                    let aspectRatio = this.video.videoWidth / this.video.videoHeight;
                    if (window.innerHeight * aspectRatio > window.innerWidth) {
                        this.width = window.innerWidth;
                        this.height = window.innerWidth / aspectRatio;
                    } else {
                        this.width = window.innerHeight * aspectRatio;
                        this.height = window.innerHeight;
                    }

                    this.videoHeight = this.video.videoHeight;
                    this.videoWidth = this.video.videoWidth;

                    this.video.setAttribute("width", this.width);
                    this.video.setAttribute("height", this.height);
                    this.canvas.setAttribute("width", this.width);
                    this.canvas.setAttribute("height", this.height);
                    this.streaming = true;
                }
            },
            false
        );
    }

    _loadImages() {
        this.images.thumbsUp = new Image();
        this.images.thumbsUp.src = "assets/img/thumbs_up.png";
        this.images.thumbsDown = new Image();
        this.images.thumbsDown.src = "assets/img/thumbs_down.png";
    }

    _frame() {
        if (this.streaming && this.enabled && this.width && this.height) {
            this.ctx.clearRect(0, 0, this.canvas.width, this.canvas.height);
            this._drawEffects();
        }
        if (this.enabled) {
            requestAnimationFrame(() => this._frame());
        }
    }

    _scaleEffect(x, y, width, height) {
        let xScale = this.width / this.videoWidth;
        let yScale = this.height / this.videoHeight;
        return {
            x: x * xScale,
            y: y * yScale,
            width: width * xScale,
            height: height * yScale
        }
    }

    _drawEffects() {
        for (let effect of this.activeEffects) {
            let { x, y, width, height } = this._scaleEffect(effect.x, effect.y, effect.width, effect.height);
            width = width * this.videoWidth * 2;
            height = height * this.videoHeight * 2;
            x = x * this.videoWidth - width / 2;
            y = y * this.videoHeight - height / 2;
            console.log(width, height);
            if (effect.type == "thumbs_down") {
                this._drawThumbsDown(x, y, width, height);
            }
            if (effect.type == "thumbs_up") {
                this._drawThumbsUp(x, y, width, height);
            }
            if (effect.type == "loading") {
                this._drawLoading(x, y, width, effect.progress);
            }
        }
    }

    _drawLoading(x, y, radius, progress) {
        this.ctx.lineWidth = this.spinnerWeight;
        this.ctx.strokeStyle = this.spinnerColor;

        this.ctx.beginPath();
        this.ctx.arc(x, y, radius, 0, progress * 2 * Math.PI);
        this.ctx.stroke();
    }

    _drawThumbsDown(x, y, width, height) {
        this.ctx.beginPath();
        this.ctx.drawImage(this.images.thumbsDown, x, y, width, height);
        this.ctx.stroke();
    }

    _drawThumbsUp(x, y, width, height) {
        this.ctx.beginPath();
        this.ctx.drawImage(this.images.thumbsUp, x, y, width, height);
        this.ctx.stroke();
    }

    setEffects(effects) {
        this.activeEffects = effects;
    }
}