import DeviceDetector from "https://cdn.skypack.dev/device-detector-js@2.2.10";
// 用法: testSupport({client?: string, os?: string}[])
// Client 和 os 是正则表达式。
// 参见: https://cdn.jsdelivr.net/npm/device-detector-js@2.2.10/README.md
// 了解 client 和 os 的合法值
testSupport([
    { client: 'Chrome' },
]);

function testSupport(supportedDevices) {
    const deviceDetector = new DeviceDetector();
    const detectedDevice = deviceDetector.parse(navigator.userAgent);
    let isSupported = false;
    for (const device of supportedDevices) {
        if (device.client !== undefined) {
            const re = new RegExp(`^${device.client}$`);
            if (!re.test(detectedDevice.client.name)) {
                continue;
            }
        }
        if (device.os !== undefined) {
            const re = new RegExp(`^${device.os}$`);
            if (!re.test(detectedDevice.os.name)) {
                continue;
            }
        }
        isSupported = true;
        break;
    }
    if (!isSupported) {
        alert(`此演示在 ${detectedDevice.client.name}/${detectedDevice.os.name} 上运行时 ` +
            `目前不能很好地支持，继续使用需自担风险。`);
    }
}

const controls = window;
const mpHolistic = window;
const drawingUtils = window;
const config = { locateFile: (file) => {
        return `https://cdn.jsdelivr.net/npm/@mediapipe/holistic@` +
            `${mpHolistic.VERSION}/${file}`;
    } };

// 我们的输入帧将来自这里。
const videoElement = document.getElementsByClassName('input_video')[0];
const canvasElement = document.getElementsByClassName('output_canvas')[0];
const controlsElement = document.getElementsByClassName('control-panel')[0];
const canvasCtx = canvasElement.getContext('2d');

// 我们稍后会将这个添加到控制面板中，但我们会在这里保存它，
// 以便每次图形运行时都可以调用 tick()。
const fpsControl = new controls.FPS();

// 优化：在隐藏动画完成后关闭动画旋转器。
const spinner = document.querySelector('.loading');
spinner.ontransitionend = () => {
    spinner.style.display = 'none';
};

function removeElements(landmarks, elements) {
    for (const element of elements) {
        delete landmarks[element];
    }
}

function removeLandmarks(results) {
    if (results.poseLandmarks) {
        removeElements(results.poseLandmarks, [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 16, 17, 18, 19, 20, 21, 22]);
    }
}

function connect(ctx, connectors) {
    const canvas = ctx.canvas;
    for (const connector of connectors) {
        const from = connector[0];
        const to = connector[1];
        if (from && to) {
            if (from.visibility && to.visibility &&
                (from.visibility < 0.1 || to.visibility < 0.1)) {
                continue;
            }
            ctx.beginPath();
            ctx.moveTo(from.x * canvas.width, from.y * canvas.height);
            ctx.lineTo(to.x * canvas.width, to.y * canvas.height);
            ctx.stroke();
        }
    }
}

let activeEffect = 'mask';

function onResults(results) {
    // 隐藏旋转器。
    document.body.classList.add('loaded');

    // 移除我们不想绘制的关键点。
    removeLandmarks(results);

    // 更新帧率。
    fpsControl.tick();

    // 绘制叠加层。
    canvasCtx.save();
    canvasCtx.clearRect(0, 0, canvasElement.width, canvasElement.height);

    if (results.segmentationMask) {
        canvasCtx.drawImage(results.segmentationMask, 0, 0, canvasElement.width, canvasElement.height);

        // 仅覆盖现有像素。
        if (activeEffect === 'mask' || activeEffect === 'both') {
            canvasCtx.globalCompositeOperation = 'source-in';
            // 这可以是颜色、纹理或其他...
            canvasCtx.fillStyle = '#00FF007F';
            canvasCtx.fillRect(0, 0, canvasElement.width, canvasElement.height);
        }
        else {
            canvasCtx.globalCompositeOperation = 'source-out';
            canvasCtx.fillStyle = '#0000FF7F';
            canvasCtx.fillRect(0, 0, canvasElement.width, canvasElement.height);
        }

        // 仅覆盖缺失的像素。
        canvasCtx.globalCompositeOperation = 'destination-atop';
        canvasCtx.drawImage(results.image, 0, 0, canvasElement.width, canvasElement.height);
        canvasCtx.globalCompositeOperation = 'source-over';
    }
    else {
        canvasCtx.drawImage(results.image, 0, 0, canvasElement.width, canvasElement.height);
    }

    // 连接肘部到手部。首先做这个，这样其他图形将绘制在这些标记之上。
    canvasCtx.lineWidth = 5;
    if (results.poseLandmarks) {
        if (results.rightHandLandmarks) {
            canvasCtx.strokeStyle = 'white';
            connect(canvasCtx, [[
                    results.poseLandmarks[mpHolistic.POSE_LANDMARKS.RIGHT_ELBOW],
                    results.rightHandLandmarks[0]
                ]]);
        }
        if (results.leftHandLandmarks) {
            canvasCtx.strokeStyle = 'white';
            connect(canvasCtx, [[
                    results.poseLandmarks[mpHolistic.POSE_LANDMARKS.LEFT_ELBOW],
                    results.leftHandLandmarks[0]
                ]]);
        }
    }

    // 姿势...
    drawingUtils.drawConnectors(canvasCtx, results.poseLandmarks, mpHolistic.POSE_CONNECTIONS, { color: 'white' });
    drawingUtils.drawLandmarks(canvasCtx, Object.values(mpHolistic.POSE_LANDMARKS_LEFT)
        .map(index => results.poseLandmarks[index]), { visibilityMin: 0.65, color: 'white', fillColor: 'rgb(255,138,0)' });
    drawingUtils.drawLandmarks(canvasCtx, Object.values(mpHolistic.POSE_LANDMARKS_RIGHT)
        .map(index => results.poseLandmarks[index]), { visibilityMin: 0.65, color: 'white', fillColor: 'rgb(0,217,231)' });

    // 手...
    drawingUtils.drawConnectors(canvasCtx, results.rightHandLandmarks, mpHolistic.HAND_CONNECTIONS, { color: 'white' });
    drawingUtils.drawLandmarks(canvasCtx, results.rightHandLandmarks, {
        color: 'white',
        fillColor: 'rgb(0,217,231)',
        lineWidth: 2,
        radius: (data) => {
            return drawingUtils.lerp(data.from.z, -0.15, .1, 10, 1);
        }
    });
    drawingUtils.drawConnectors(canvasCtx, results.leftHandLandmarks, mpHolistic.HAND_CONNECTIONS, { color: 'white' });
    drawingUtils.drawLandmarks(canvasCtx, results.leftHandLandmarks, {
        color: 'white',
        fillColor: 'rgb(255,138,0)',
        lineWidth: 2,
        radius: (data) => {
            return drawingUtils.lerp(data.from.z, -0.15, .1, 10, 1);
        }
    });

    // 面部...
    drawingUtils.drawConnectors(canvasCtx, results.faceLandmarks, mpHolistic.FACEMESH_TESSELATION, { color: '#C0C0C070', lineWidth: 1 });
    drawingUtils.drawConnectors(canvasCtx, results.faceLandmarks, mpHolistic.FACEMESH_RIGHT_EYE, { color: 'rgb(0,217,231)' });
    drawingUtils.drawConnectors(canvasCtx, results.faceLandmarks, mpHolistic.FACEMESH_RIGHT_EYEBROW, { color: 'rgb(0,217,231)' });
    drawingUtils.drawConnectors(canvasCtx, results.faceLandmarks, mpHolistic.FACEMESH_LEFT_EYE, { color: 'rgb(255,138,0)' });
    drawingUtils.drawConnectors(canvasCtx, results.faceLandmarks, mpHolistic.FACEMESH_LEFT_EYEBROW, { color: 'rgb(255,138,0)' });
    drawingUtils.drawConnectors(canvasCtx, results.faceLandmarks, mpHolistic.FACEMESH_FACE_OVAL, { color: '#E0E0E0', lineWidth: 5 });
    drawingUtils.drawConnectors(canvasCtx, results.faceLandmarks, mpHolistic.FACEMESH_LIPS, { color: '#E0E0E0', lineWidth: 5 });

    canvasCtx.restore();
}

const holistic = new mpHolistic.Holistic(config);
holistic.onResults(onResults);

// 呈现一个控制面板，用户可以通过它操作解决方案选项。
new controls
    .ControlPanel(controlsElement, {
    selfieMode: true,
    modelComplexity: 1,
    smoothLandmarks: true,
    enableSegmentation: false,
    smoothSegmentation: true,
    minDetectionConfidence: 0.5,
    minTrackingConfidence: 0.5,
    effect: 'background',
})
    .add([
    new controls.StaticText({ title: 'MediaPipe 全身姿态检测' }),
    fpsControl,
    new controls.Toggle({ title: '自拍模式', field: 'selfieMode' }),
    new controls.SourcePicker({
        onSourceChanged: () => {
            // 重置，因为在源更改之间重置时，姿势会给出更好的结果。
            holistic.reset();
        },
        onFrame: async (input, size) => {
            const aspect = size.height / size.width;
            let width, height;
            if (window.innerWidth > window.innerHeight) {
                height = window.innerHeight;
                width = height / aspect;
            }
            else {
                width = window.innerWidth;
                height = width * aspect;
            }
            canvasElement.width = width;
            canvasElement.height = height;
            await holistic.send({ image: input });
        },
    }),
    new controls.Slider({
        title: '模型复杂度',
        field: 'modelComplexity',
        discrete: ['轻量', '完整', '重度'],
    }),
    new controls.Toggle({ title: '平滑关键点', field: 'smoothLandmarks' }),
    new controls.Toggle({ title: '启用分割', field: 'enableSegmentation' }),
    new controls.Toggle({ title: '平滑分割', field: 'smoothSegmentation' }),
    new controls.Slider({
        title: '最小检测置信度',
        field: 'minDetectionConfidence',
        range: [0, 1],
        step: 0.01
    }),
    new controls.Slider({
        title: '最小跟踪置信度',
        field: 'minTrackingConfidence',
        range: [0, 1],
        step: 0.01
    }),
    new controls.Slider({
        title: '效果',
        field: 'effect',
        discrete: { 'background': '背景', 'mask': '前景' },
    }),
])
    .on(x => {
    const options = x;
    videoElement.classList.toggle('selfie', options.selfieMode);
    activeEffect = x['effect'];
    holistic.setOptions(options);
});

// 添加窗口大小调整事件监听器，以确保画布大小随窗口变化而调整
window.addEventListener('resize', () => {
    const aspect = videoElement.videoHeight / videoElement.videoWidth;
    let width, height;
    if (window.innerWidth > window.innerHeight) {
        height = window.innerHeight;
        width = height / aspect;
    }
    else {
        width = window.innerWidth;
        height = width * aspect;
    }
    canvasElement.width = width;
    canvasElement.height = height;
});