// 点（x,y）围绕中心（cx,cy）旋转deg度

const rotate = function (cx: number, cy: number, deg: number, x: number, y: number) {
    const cos = Math.cos(deg), sin = Math.sin(deg)
    return [
        +((x - cx) * cos - (y - cy) * sin + cx).toFixed(7),
        +((x - cx) * sin + (y - cy) * cos + cy).toFixed(7)
    ]
}

// r1和r2，内半径和外半径
// beginA起点弧度，rotateA旋转弧度式

export default function (beginA: number, rotateA: number, cx: number, cy: number, r1: number, r2: number, doback: Function) {

    // 保证逆时针也是可以的
    if (rotateA < 0) {
        beginA += rotateA
        rotateA *= -1
    }

    const temp: number[] = []
    let p: number[]

    // 内部
    p = rotate(0, 0, beginA, r1, 0)
    temp[0] = p[0]
    temp[1] = p[1]
    p = rotate(0, 0, rotateA, p[0], p[1])
    temp[2] = p[0]
    temp[3] = p[1]

    // 外部
    p = rotate(0, 0, beginA, r2, 0)
    temp[4] = p[0]
    temp[5] = p[1]
    p = rotate(0, 0, rotateA, p[0], p[1])
    temp[6] = p[0]
    temp[7] = p[1]

    doback(
        beginA, beginA + rotateA,
        temp[0] + cx, temp[1] + cy,
        temp[4] + cx, temp[5] + cy,
        temp[2] + cx, temp[3] + cy,
        temp[6] + cx, temp[7] + cy,
        (r2 - r1) * 0.5
    )

}