如何按月然后按客户将一系列产品销售分组

一年中，我为许多客户存储了一系列不同的产品销售，每个月都有存储。我希望能够将一年内购买的客户分组为一个列。

var sales = [
  ["Jan", "Customer 1", "Product 1", 538]
  ["Feb", "Customer 1", "Product 1", 0]
  ["March", "Customer 1", "Product 1", 252]
  ["Apr", "Customer 1", "Product 1", 0]
  ["May", "Customer 1", "Product 1", 630]
  ["June", "Customer 1", "Product 1", 945]
  ["July", "Customer 1", "Product 1", 0]
  ["Aug", "Customer 1", "Product 1", 630]
  ["Sept", "Customer 1", "Product 1", 756]
  ["Oct", "Customer 1", "Product 1", 0]
  ["Nov", "Customer 1", "Product 1", 0]
  ["Dec", "Customer 1", "Product 1", 630]
  ["Jan", "Customer 1", "Product 2", 50]
  ["Feb", "Customer 1", "Product 2", 630]
  ...
]

我尝试将独特的产品分组，然后获得独特的客户，然后获得独特的产品，如下所示，但我不知道如何从这里继续前进。

// Get a list of unique products
var products = sales.map(item => {
  return item[2];
}).filter((val, index, self) => {
  return self.indexOf(val) === index;
});
console.log(products);

// Ge a list of unique customers
var targets = sales.map(item => {
  return item[1]
}).filter((val, index, self) => {
  return self.indexOf(val) === index
});
console.log(targets);

我想要一组按客户和产品分组的对象

[
  {
    "customer": "Customer 1",
    "product": "Product 1",
    "jan" 538,
    "feb": 0,
    "march": 252
    ...
  },
  {
    "customer": "Customer 1",
    "product": "Product 2",
    "jan" 50,
    "feb": 630,
    ...
  }
]

有任何想法吗？