busy-web/ember-date-time

/**
 * @module Utils/Clock
 *
 */
import { Snap } from 'snapsvg';

export function getBoundsCenter(width, height) {
    const cx = (width / 2);
    const cy = (height / 2);
    const r = ( height < width ) ? cx : cy;
    return { cx, cy, r };
}

/**
    * Returns the degree of a slice in the circle for a va
    * total number passed in.
    *
    * @public
    * @method getSliceDegree
    * @param totalSlices {number} the total number of slices this circle is broken into
    * @param slice{number} the slice number to get the degrees of
    * @return {number}
    */
export function getSliceDegree(totalSlices, slice) {
    return (slice * (360 / totalSlices)) % 360;
}

/**
    * Returns the degree of a specified value as it pertains to the
    * total number passed in.
    *
    * @public
    * @method getValueFromDegree
    * @param totalSlices {number} the total number of slices this circle is broken into
    * @param degree {number} the degree to get the number for
    * @return {number}
    */
export function getSliceFromDegree(totalSlices, degree) {
    // find the slice number
    return (degree * totalSlices) / 360;
}

export function getLineFromDegree(degree, length, x1, y1) {
    // getSliceDegree will calculate all angles according to the positive x axis
    // so rotate all degrees by 270 to get the proper alignment of time per degree on the clock
    degree = (degree + 270) % 360;

    // convert degrees to radians
    let rads = Snap.rad(degree);

    // calculate x and y
    let x2 = x1 + length * Math.cos(rads);
    let y2 = y1 + length * Math.sin(rads);

    return { x1, y1, x2, y2 };
}

/**
 * calculates the angle of a line
 *
 * @method angleOfLine
 * @param x1 {number}
 * @param y1 {number}
 * @param x2 {number}
 * @param y2 {number}
 * @return {number} angle in degrees
 */
export function angleOfLine(x1, y1, x2, y2) {
    let dy = -(y1 - y2); // invert dy for proper x-axis
    let dx = x1 - x2;


    // returns the angle of a line off the x-axis
    let angle = Math.atan2(dy, dx);
    angle *= 180 / Math.PI;

    // invert the angle to make work on the y-axis
    angle = -angle;

    // convert to 360 degree angles
    if (angle < 0) {
        angle += 360;
    }

    // rotate the angle back up to the y-axis 0 coordinate
    angle = (angle + 90) % 360;
    return angle;
}

/**
 * returns the direction of the angle ????
 * was called `calculateDirection`
 *
 * @method getDirection
 * @param startAngle {number}
 * @param endAngle {number}
 * @return {number} angle
 */
export function getDirection(startAngle, endAngle) {
    let angle = endAngle - startAngle;
    if (angle > 180) {
        angle -= 360;
    }
    return angle;
}

export function createSVGPath(totalSlices, degree, x, y, start, end) {
    const sliceRange = ((360 / totalSlices) / 2);
    const ld = (((degree - sliceRange) + 360) % 360); // get the angle for the left bounds
    const rd = ((degree + sliceRange) % 360); // get the angle for the right bounds

    // get the bottom left and right points
    const bl = getLineFromDegree(ld, start, x, y);        // bottom left
    const br = getLineFromDegree(rd, start, x, y);        // bottom right

    // get the top left and right points
    const tl = getLineFromDegree(ld, end, x, y);            // top left
    const tr = getLineFromDegree(rd, end, x, y);            // top right

    // get the point to curve the top bar to.
    const tc = getLineFromDegree(degree, end, x, y);    // top center

    const M = `M${tl.x2} ${tl.y2}`;
    const Q = `Q ${tc.x2} ${tc.y2} ${tr.x2} ${tr.y2}`;
    const L = `L ${br.x2} ${br.y2} ${bl.x2} ${bl.y2} Z`;

    const d = `${M} ${Q} ${L}`;
    return { d };
}