import "../math/trigonometry";

import "equirectangular";

import "geo";

d3.geo.rotation = function(rotate) {

rotate = d3_geo_rotation(rotate[0] % 360 * d3_radians, rotate[1] * d3_radians, rotate.length > 2 ? rotate[2] * d3_radians : 0);

function forward(coordinates) {

coordinates = rotate(coordinates[0] * d3_radians, coordinates[1] * d3_radians);

return coordinates[0] *= d3_degrees, coordinates[1] *= d3_degrees, coordinates;

}

forward.invert = function(coordinates) {

coordinates = rotate.invert(coordinates[0] * d3_radians, coordinates[1] * d3_radians);

return coordinates[0] *= d3_degrees, coordinates[1] *= d3_degrees, coordinates;

};

return forward;

};

// Note: |δλ| must be < 2π

function d3_geo_rotation(δλ, δφ, δγ) {

return δλ ? (δφ || δγ ? d3_geo_compose(d3_geo_rotationλ(δλ), d3_geo_rotationφγ(δφ, δγ))

: d3_geo_rotationλ(δλ))

: (δφ || δγ ? d3_geo_rotationφγ(δφ, δγ)

: d3_geo_equirectangular);

}

function d3_geo_forwardRotationλ(δλ) {

return function(λ, φ) {

return λ += δλ, [λ > π ? λ - 2 * π : λ < -π ? λ + 2 * π : λ, φ];

};

}

function d3_geo_rotationλ(δλ) {

var rotation = d3_geo_forwardRotationλ(δλ);

rotation.invert = d3_geo_forwardRotationλ(-δλ);

return rotation;

}

function d3_geo_rotationφγ(δφ, δγ) {

var cosδφ = Math.cos(δφ),

sinδφ = Math.sin(δφ),

cosδγ = Math.cos(δγ),

sinδγ = Math.sin(δγ);

function rotation(λ, φ) {

var cosφ = Math.cos(φ),

x = Math.cos(λ) * cosφ,

y = Math.sin(λ) * cosφ,

z = Math.sin(φ),

k = z * cosδφ + x * sinδφ;

return [

Math.atan2(y * cosδγ - k * sinδγ, x * cosδφ - z * sinδφ),

Math.asin(Math.max(-1, Math.min(1, k * cosδγ + y * sinδγ)))

];

}

rotation.invert = function(λ, φ) {

var cosφ = Math.cos(φ),

x = Math.cos(λ) * cosφ,

y = Math.sin(λ) * cosφ,

z = Math.sin(φ),

k = z * cosδγ - y * sinδγ;

return [

Math.atan2(y * cosδγ + z * sinδγ, x * cosδφ + k * sinδφ),

Math.asin(Math.max(-1, Math.min(1, k * cosδφ - x * sinδφ)))

];

};

return rotation;

}