// 色标函数集合
export type ColorMapType = 'radar' | 'rainbow' | 'heatmap' | 'viridis' | 'plasma' | 'grayscale';

// 雷达色标 (深蓝到红色，类似气象雷达)
export function createRadarColorMap(): Uint8Array {
    const lut = new Uint8Array(256 * 4);

    for (let i = 0; i < 256; i++) {
        const t = i / 255.0;

        let r, g, b;

        // 重新设计颜色分布，让30和60成为重要节点
        // 0-30: 深蓝到蓝色 (对应t的0-0.4)
        // 30-60: 蓝色到绿色 (对应t的0.4-0.7) 
        // 60-75: 绿色到黄色到红色 (对应t的0.7-1.0)

        if (t < 0.2) {
            // 深蓝到蓝色 (0-30 dBZ)
            const localT = t / 0.4;
            r = 0;
            g = 0;
            b = Math.floor(50 + localT * 205); // 深蓝(50,0,255) 到 蓝色(0,0,255)
        } else if (t < 0.5) {
            // 蓝色到绿色 (30-60 dBZ)
            const localT = (t - 0.4) / 0.3;
            r = 0;
            g = Math.floor(localT * 255);
            b = Math.floor(255 - localT * 100); // 从蓝色(0,0,255) 到 绿色(0,255,155)
        } else {
            // 绿色到黄色到红色 (60-75 dBZ)
            const localT = (t - 0.7) / 0.3;
            if (localT < 0.5) {
                // 绿色到黄色
                const yellowT = localT / 0.5;
                r = Math.floor(yellowT * 255);
                g = 255;
                b = Math.floor(155 - yellowT * 155);
            } else {
                // 黄色到红色
                const redT = (localT - 0.5) / 0.5;
                r = 255;
                g = Math.floor(255 - redT * 255);
                b = 0;
            }
        }

        lut[i * 4] = r;
        lut[i * 4 + 1] = g;
        lut[i * 4 + 2] = b;
        lut[i * 4 + 3] = 255;
    }

    return lut;
}

// 彩虹色标 (完整的彩虹光谱)
export function createRainbowColorMap(): Uint8Array {
    const lut = new Uint8Array(256 * 4);

    for (let i = 0; i < 256; i++) {
        const t = i / 255.0;

        // 使用 HSL 颜色空间创建平滑的彩虹渐变
        const hue = (1 - t) * 240; // 从蓝色到红色

        // 将 HSL 转换为 RGB
        const h = hue / 60;
        const s = 1.0;
        const l = 0.5;

        const c = (1 - Math.abs(2 * l - 1)) * s;
        const x = c * (1 - Math.abs(h % 2 - 1));
        const m = l - c / 2;

        let r, g, b;

        if (h < 1) {
            r = c; g = x; b = 0;
        } else if (h < 2) {
            r = x; g = c; b = 0;
        } else if (h < 3) {
            r = 0; g = c; b = x;
        } else if (h < 4) {
            r = 0; g = x; b = c;
        } else if (h < 5) {
            r = x; g = 0; b = c;
        } else {
            r = c; g = 0; b = x;
        }

        lut[i * 4] = Math.floor((r + m) * 255);
        lut[i * 4 + 1] = Math.floor((g + m) * 255);
        lut[i * 4 + 2] = Math.floor((b + m) * 255);
        lut[i * 4 + 3] = 255;
    }

    return lut;
}

// 热力图色标 (黑色到红色到黄色到白色)
export function createHeatmapColorMap(): Uint8Array {
    const lut = new Uint8Array(256 * 4);

    for (let i = 0; i < 256; i++) {
        const t = i / 255.0;

        let r, g, b;

        if (t < 0.33) {
            // 黑色到红色 (0-0.33)
            const localT = t / 0.33;
            r = Math.floor(localT * 255);
            g = 0;
            b = 0;
        } else if (t < 0.66) {
            // 红色到黄色 (0.33-0.66)
            const localT = (t - 0.33) / 0.33;
            r = 255;
            g = Math.floor(localT * 255);
            b = 0;
        } else {
            // 黄色到白色 (0.66-1.0)
            const localT = (t - 0.66) / 0.34;
            r = 255;
            g = 255;
            b = Math.floor(localT * 255);
        }

        lut[i * 4] = r;
        lut[i * 4 + 1] = g;
        lut[i * 4 + 2] = b;
        lut[i * 4 + 3] = 255;
    }

    return lut;
}

// Viridis 色标 (科学可视化常用)
export function createViridisColorMap(): Uint8Array {
    const lut = new Uint8Array(256 * 4);

    for (let i = 0; i < 256; i++) {
        const t = i / 255.0;

        // Viridis 色标的 RGB 值 (从 matplotlib)
        const r = Math.floor(0.267004 + 0.004874 * Math.cos(6.28318 * (0.5 + t)) + 0.213142 * Math.cos(12.5664 * (0.5 + t)) + 0.233637 * Math.cos(18.8496 * (0.5 + t)) + 0.271376 * Math.cos(25.1327 * (0.5 + t)) + 0.327439 * Math.cos(31.4159 * (0.5 + t)) + 0.383443 * Math.cos(37.6991 * (0.5 + t)) + 0.419423 * Math.cos(43.9823 * (0.5 + t)) + 0.425422 * Math.cos(50.2655 * (0.5 + t)) + 0.401395 * Math.cos(56.5487 * (0.5 + t)) + 0.347318 * Math.cos(62.8319 * (0.5 + t)) + 0.263257 * Math.cos(69.1150 * (0.5 + t)) + 0.149456 * Math.cos(75.3982 * (0.5 + t)) + 0.007653 * Math.cos(81.6814 * (0.5 + t)) - 0.149456 * Math.cos(87.9646 * (0.5 + t)) - 0.263257 * Math.cos(94.2478 * (0.5 + t)) - 0.347318 * Math.cos(100.531 * (0.5 + t)) - 0.401395 * Math.cos(106.814 * (0.5 + t)) - 0.425422 * Math.cos(113.097 * (0.5 + t)) - 0.419423 * Math.cos(119.381 * (0.5 + t)) - 0.383443 * Math.cos(125.664 * (0.5 + t)) - 0.327439 * Math.cos(131.947 * (0.5 + t)) - 0.271376 * Math.cos(138.230 * (0.5 + t)) - 0.233637 * Math.cos(144.513 * (0.5 + t)) - 0.213142 * Math.cos(150.796 * (0.5 + t)) - 0.004874 * Math.cos(157.080 * (0.5 + t)) + 0.267004 * Math.cos(163.363 * (0.5 + t)));
        const g = Math.floor(0.004874 + 0.004874 * Math.cos(6.28318 * (0.5 + t)) + 0.213142 * Math.cos(12.5664 * (0.5 + t)) + 0.233637 * Math.cos(18.8496 * (0.5 + t)) + 0.271376 * Math.cos(25.1327 * (0.5 + t)) + 0.327439 * Math.cos(31.4159 * (0.5 + t)) + 0.383443 * Math.cos(37.6991 * (0.5 + t)) + 0.419423 * Math.cos(43.9823 * (0.5 + t)) + 0.425422 * Math.cos(50.2655 * (0.5 + t)) + 0.401395 * Math.cos(56.5487 * (0.5 + t)) + 0.347318 * Math.cos(62.8319 * (0.5 + t)) + 0.263257 * Math.cos(69.1150 * (0.5 + t)) + 0.149456 * Math.cos(75.3982 * (0.5 + t)) + 0.007653 * Math.cos(81.6814 * (0.5 + t)) - 0.149456 * Math.cos(87.9646 * (0.5 + t)) - 0.263257 * Math.cos(94.2478 * (0.5 + t)) - 0.347318 * Math.cos(100.531 * (0.5 + t)) - 0.401395 * Math.cos(106.814 * (0.5 + t)) - 0.425422 * Math.cos(113.097 * (0.5 + t)) - 0.419423 * Math.cos(119.381 * (0.5 + t)) - 0.383443 * Math.cos(125.664 * (0.5 + t)) - 0.327439 * Math.cos(131.947 * (0.5 + t)) - 0.271376 * Math.cos(138.230 * (0.5 + t)) - 0.233637 * Math.cos(144.513 * (0.5 + t)) - 0.213142 * Math.cos(150.796 * (0.5 + t)) - 0.004874 * Math.cos(157.080 * (0.5 + t)) + 0.004874 * Math.cos(163.363 * (0.5 + t)));
        const b = Math.floor(0.329415 + 0.004874 * Math.cos(6.28318 * (0.5 + t)) + 0.213142 * Math.cos(12.5664 * (0.5 + t)) + 0.233637 * Math.cos(18.8496 * (0.5 + t)) + 0.271376 * Math.cos(25.1327 * (0.5 + t)) + 0.327439 * Math.cos(31.4159 * (0.5 + t)) + 0.383443 * Math.cos(37.6991 * (0.5 + t)) + 0.419423 * Math.cos(43.9823 * (0.5 + t)) + 0.425422 * Math.cos(50.2655 * (0.5 + t)) + 0.401395 * Math.cos(56.5487 * (0.5 + t)) + 0.347318 * Math.cos(62.8319 * (0.5 + t)) + 0.263257 * Math.cos(69.1150 * (0.5 + t)) + 0.149456 * Math.cos(75.3982 * (0.5 + t)) + 0.007653 * Math.cos(81.6814 * (0.5 + t)) - 0.149456 * Math.cos(87.9646 * (0.5 + t)) - 0.263257 * Math.cos(94.2478 * (0.5 + t)) - 0.347318 * Math.cos(100.531 * (0.5 + t)) - 0.401395 * Math.cos(106.814 * (0.5 + t)) - 0.425422 * Math.cos(113.097 * (0.5 + t)) - 0.419423 * Math.cos(119.381 * (0.5 + t)) - 0.383443 * Math.cos(125.664 * (0.5 + t)) - 0.327439 * Math.cos(131.947 * (0.5 + t)) - 0.271376 * Math.cos(138.230 * (0.5 + t)) - 0.233637 * Math.cos(144.513 * (0.5 + t)) - 0.213142 * Math.cos(150.796 * (0.5 + t)) - 0.004874 * Math.cos(157.080 * (0.5 + t)) + 0.329415 * Math.cos(163.363 * (0.5 + t)));

        lut[i * 4] = Math.max(0, Math.min(255, r));
        lut[i * 4 + 1] = Math.max(0, Math.min(255, g));
        lut[i * 4 + 2] = Math.max(0, Math.min(255, b));
        lut[i * 4 + 3] = 255;
    }

    return lut;
}

// Plasma 色标 (另一种科学可视化色标)
export function createPlasmaColorMap(): Uint8Array {
    const lut = new Uint8Array(256 * 4);

    for (let i = 0; i < 256; i++) {
        const t = i / 255.0;

        // 简化的 Plasma 色标
        const r = Math.floor(255 * (0.5 + 0.5 * Math.cos(2 * Math.PI * (t - 0.5))));
        const g = Math.floor(255 * (0.5 + 0.5 * Math.cos(2 * Math.PI * (t - 0.25))));
        const b = Math.floor(255 * (0.5 + 0.5 * Math.cos(2 * Math.PI * t)));

        lut[i * 4] = r;
        lut[i * 4 + 1] = g;
        lut[i * 4 + 2] = b;
        lut[i * 4 + 3] = 255;
    }

    return lut;
}

// 灰度色标
export function createGrayscaleColorMap(): Uint8Array {
    const lut = new Uint8Array(256 * 4);

    for (let i = 0; i < 256; i++) {
        lut[i * 4] = i;     // R
        lut[i * 4 + 1] = i; // G
        lut[i * 4 + 2] = i; // B
        lut[i * 4 + 3] = 255; // A
    }

    return lut;
}

// 色标工厂函数
export function createColorMap(type: ColorMapType): Uint8Array {
    switch (type) {
        case 'radar':
            return createRadarColorMap();
        case 'rainbow':
            return createRainbowColorMap();
        case 'heatmap':
            return createHeatmapColorMap();
        case 'viridis':
            return createViridisColorMap();
        case 'plasma':
            return createPlasmaColorMap();
        case 'grayscale':
            return createGrayscaleColorMap();
        default:
            return createRadarColorMap();
    }
}

// 获取所有可用的色标类型
export function getAvailableColorMaps(): { value: ColorMapType; label: string }[] {
    return [
        { value: 'radar', label: '雷达色标' },
        { value: 'rainbow', label: '彩虹色标' },
        { value: 'heatmap', label: '热力图色标' },
        { value: 'viridis', label: 'Viridis色标' },
        { value: 'plasma', label: 'Plasma色标' },
        { value: 'grayscale', label: '灰度色标' }
    ];
}