/*
Copyright 2014 Google Inc. All rights reserved.

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/

package s2

import (
	"reflect"
	"testing"

	"github.com/golang/geo/r1"
	"github.com/golang/geo/r3"
	"github.com/golang/geo/s1"
)

func TestKmToAngle(t *testing.T) {
	const earthRadiusKm = 6371.01

	tests := []struct {
		have float64
		want s1.Angle
	}{
		{0.0, 0.0},
		{1.0, 0.00015696098420815537 * s1.Radian},
		{earthRadiusKm, 1.0 * s1.Radian},
		{-1.0, -0.00015696098420815537 * s1.Radian},
		{-10000.0, -1.5696098420815536300 * s1.Radian},
		{1e9, 156960.984208155363007 * s1.Radian},
	}
	for _, test := range tests {
		if got := kmToAngle(test.have); !float64Eq(float64(got), float64(test.want)) {
			t.Errorf("kmToAngle(%f) = %0.20f, want %0.20f", test.have, got, test.want)
		}
	}

}

func TestParsePoint(t *testing.T) {
	tests := []struct {
		have string
		want Point
	}{
		{"0:0", Point{r3.Vector{1, 0, 0}}},
		{"90:0", Point{r3.Vector{6.123233995736757e-17, 0, 1}}},
		{"91:0", Point{r3.Vector{-0.017452406437283473, -0, 0.9998476951563913}}},
		{"179.99:0", Point{r3.Vector{-0.9999999847691292, -0, 0.00017453292431344843}}},
		{"180:0", Point{r3.Vector{-1, -0, 1.2246467991473515e-16}}},
		{"181.0:0", Point{r3.Vector{-0.9998476951563913, -0, -0.017452406437283637}}},
		{"-45:0", Point{r3.Vector{0.7071067811865476, 0, -0.7071067811865475}}},
		{"0:0.01", Point{r3.Vector{0.9999999847691292, 0.00017453292431333684, 0}}},
		{"0:30", Point{r3.Vector{0.8660254037844387, 0.49999999999999994, 0}}},
		{"0:45", Point{r3.Vector{0.7071067811865476, 0.7071067811865475, 0}}},
		{"0:90", Point{r3.Vector{6.123233995736757e-17, 1, 0}}},
		{"30:30", Point{r3.Vector{0.7500000000000001, 0.4330127018922193, 0.49999999999999994}}},
		{"-30:30", Point{r3.Vector{0.7500000000000001, 0.4330127018922193, -0.49999999999999994}}},
		{"180:90", Point{r3.Vector{-6.123233995736757e-17, -1, 1.2246467991473515e-16}}},
		{"37.4210:-122.0866, 37.4231:-122.0819", Point{r3.Vector{-0.4218751185559026, -0.6728760966593905, 0.6076669670863027}}},
	}
	for _, test := range tests {
		if got := parsePoint(test.have); !got.ApproxEqual(test.want) {
			t.Errorf("parsePoint(%s) = %v, want %v", test.have, got, test.want)
		}
	}
}

func TestParseRect(t *testing.T) {
	tests := []struct {
		have string
		want Rect
	}{
		{"0:0", Rect{}},
		{
			"1:1",
			Rect{
				r1.Interval{float64(s1.Degree), float64(s1.Degree)},
				s1.Interval{float64(s1.Degree), float64(s1.Degree)},
			},
		},
		{
			"1:1, 2:2, 3:3",
			Rect{
				r1.Interval{float64(s1.Degree), 3 * float64(s1.Degree)},
				s1.Interval{float64(s1.Degree), 3 * float64(s1.Degree)},
			},
		},
		{
			"-90:-180, 90:180",
			Rect{
				r1.Interval{-90 * float64(s1.Degree), 90 * float64(s1.Degree)},
				s1.Interval{180 * float64(s1.Degree), -180 * float64(s1.Degree)},
			},
		},
		{
			"-89.99:0, 89.99:179.99",
			Rect{
				r1.Interval{-89.99 * float64(s1.Degree), 89.99 * float64(s1.Degree)},
				s1.Interval{0, 179.99 * float64(s1.Degree)},
			},
		},
		{
			"-89.99:-179.99, 89.99:179.99",
			Rect{
				r1.Interval{-89.99 * float64(s1.Degree), 89.99 * float64(s1.Degree)},
				s1.Interval{179.99 * float64(s1.Degree), -179.99 * float64(s1.Degree)},
			},
		},
		{
			"37.4210:-122.0866, 37.4231:-122.0819",
			Rect{
				r1.Interval{float64(s1.Degree * 37.4210), float64(s1.Degree * 37.4231)},
				s1.Interval{float64(s1.Degree * -122.0866), float64(s1.Degree * -122.0819)},
			},
		},
		{
			"-876.54:-654.43, 963.84:2468.35",
			Rect{
				r1.Interval{-876.54 * float64(s1.Degree), -876.54 * float64(s1.Degree)},
				s1.Interval{-654.43 * float64(s1.Degree), -654.43 * float64(s1.Degree)},
			},
		},
	}
	for _, test := range tests {
		if got := parseRect(test.have); got != test.want {
			t.Errorf("parseRect(%s) = %v, want %v", test.have, got, test.want)
		}
	}
}

func TestParseLatLngs(t *testing.T) {
	tests := []struct {
		have string
		want []LatLng
	}{
		{"0:0", []LatLng{{0, 0}}},
		{
			"37.4210:-122.0866, 37.4231:-122.0819",
			[]LatLng{
				{s1.Degree * 37.4210, s1.Degree * -122.0866},
				{s1.Degree * 37.4231, s1.Degree * -122.0819},
			},
		},
	}
	for _, test := range tests {
		got := parseLatLngs(test.have)
		if !reflect.DeepEqual(got, test.want) {
			t.Errorf("parseLatLngs(%s) = %v, want %v", test.have, got, test.want)
		}
	}
}

func TestParsePoints(t *testing.T) {
	tests := []struct {
		have string
		want []Point
	}{
		{"0:0", []Point{{r3.Vector{1, 0, 0}}}},
		{"      0:0,    ", []Point{{r3.Vector{1, 0, 0}}}},
		{
			"90:0,-90:0",
			[]Point{
				{r3.Vector{6.123233995736757e-17, 0, 1}},
				{r3.Vector{6.123233995736757e-17, 0, -1}},
			},
		},
		{
			"90:0, 0:90, -90:0, 0:-90",
			[]Point{
				{r3.Vector{6.123233995736757e-17, 0, 1}},
				{r3.Vector{6.123233995736757e-17, 1, 0}},
				{r3.Vector{6.123233995736757e-17, 0, -1}},
				{r3.Vector{6.123233995736757e-17, -1, 0}},
			},
		},
	}

	for _, test := range tests {
		got := parsePoints(test.have)
		for i := range got { // assume we at least get the same number of points
			if !got[i].ApproxEqual(test.want[i]) {
				t.Errorf("parsePoints(%s): [%d]: got %v, want %v", test.have, i, got[i], test.want[i])
			}
		}
	}
}