// test kronecker product
var assert = require('assert'),
    math = require('../../../index');

describe('kron', function() {

  it('should calculate the kronecker product of two arrays', function() {
      assert.deepEqual(math.kron([
          [1, -2, 1],
          [1, 1, 0]
      ], [
          [1, 0],
          [0, 1]
      ]), [
          [1, 0, -2, -0, 1, 0],
          [0, 1, -0, -2, 0, 1],
          [1, 0, 1, 0, 0, 0],
          [0, 1, 0, 1, 0, 0]
      ]);
      assert.deepEqual(math.kron([
          [53, 12, -9, 0],
          [2, 2, 5, 2]
      ], [
          [99, 56, 22, 7]
      ]), [
          [5247, 2968, 1166, 371, 1188, 672, 264, 84, -891, -504, -198, -63, 0, 0, 0, 0],
          [198, 112, 44, 14, 198, 112, 44, 14, 495, 280, 110, 35, 198, 112, 44, 14]
      ]);
  });

  it('should calculate product for empty 2D Arrays', function() {
    assert.deepEqual(math.kron([[]], [[]]), [[]]);
  });

  it('should calculate product for 1D Arrays', function() {
    assert.deepEqual(math.kron([1,1], [[1,0],[0,1]]), [[1, 0, 1, 0],[0, 1, 0, 1]]);
    assert.deepEqual(math.kron([[1,0],[0,1]], [1,1]), [[1, 1, 0, 0],[0, 0, 1, 1]]);
    assert.deepEqual(math.kron([1,2,6,8], [12,1,2,3]), [[12,1,2,3,24,2,4,6,72,6,12,18,96,8,16,24]]);
  });

  it('should support complex numbers', function() {
    assert.deepEqual(math.kron([
      [1,math.complex(0,1)],
      [math.complex(0,1),2]
    ],
    [
      [2,2],
      [2,2]
    ]),
    [
      [2,2,math.complex(0,2),math.complex(0,2)],
      [2,2,math.complex(0,2),math.complex(0,2)],
      [math.complex(0,2),math.complex(0,2),4,4],
      [math.complex(0,2),math.complex(0,2),4,4]
    ]);
  });

  it('should throw an error for greater then 2 dimensions', function() {
    assert.throws(function () {
      math.kron([[[1, 1], [1, 1]], [[1, 1], [1, 1]]], [[[1, 2, 3], [4, 5, 6]], [[6, 7, 8], [9, 10, 11]]]);
    });
  });

  it('should throw an error if called with an invalid number of arguments', function() {
    assert.throws(function () {math.kron();}, TypeError);
    assert.throws(function () {math.kron([[1,2]]);}, TypeError);
  });

  describe('DenseMatrix', function () {

    it('should calculate the kronecker product of a 2d matrix', function() {
      var y = math.matrix([[1, 1], [1, 1]]);
      var x = math.matrix([[1, 0], [0, 1]]);
      var product = math.kron(x, y);
      assert.deepEqual(product.valueOf(), [[1,1,0,0],[1,1,0,0],[0,0,1,1],[0,0,1,1]]);

      var y = math.matrix([[1, 2], [55, -1]]);
      var x = math.matrix([[13, 0], [0, -1]]);
      var product = math.kron(x, y);
      assert.deepEqual(product.toArray(), [[13,26,0,0],[715,-13,0,-0],[0,0,-1,-2],[0,0,-55,1]]);
    });

    it('should throw an error for invalid kronecker product of matrix', function() {
      y = math.matrix([[[]]]);
      x = math.matrix([[[1,1], [1,1]], [[1,1], [1,1]]]);
      assert.throws(function () { math.kron(y, x) });
    });
  });

  describe('SparseMatrix', function () {
    it('should calculate the kronecker product of a 2d matrix', function() {
      var y = math.sparse([[1, 1], [1, 1]]);
      var x = math.sparse([[1, 0], [0, 1]]);
      var product = math.kron(x, y);
      assert.deepEqual(product.valueOf(), [[1,1,0,0],[1,1,0,0],[0,0,1,1],[0,0,1,1]]);

      var y = math.matrix([[1, 2], [55, -1]], 'sparse');
      var x = math.matrix([[13, 0], [0, -1]], 'sparse');
      var product = math.kron(x, y);
      assert.deepEqual(product.toArray(), [[13,26,0,0],[715,-13,0,-0],[0,0,-1,-2],[0,0,-55,1]]);
    });
  });
});