package lulu

// TODO: should we remove the redundant tax/subtotal fields or remain
// true to their retarded api?

import (
	"encoding/json"
	"fmt"

	"github.com/shopspring/decimal"
)

// printJobCostReq is the json body of a /print-job-cost-calculations/ request.
type printJobCostReq struct {
	LineItems []printJobCostLineItem `json:"line_items"`
	ShipAddr  ShippingAddress        `json:"shipping_address"`
	ShipOpt   ShippingLevel          `json:"shipping_option"`
}

type printJobCostLineItem struct {
	NPages   uint  `json:"page_count"`
	Mfg      PkgId `json:"pod_package_id"`
	Quantity uint  `json:"quantity"`
}

// PrintJobCost is the response from /print-job-cost-calculations/.
type PrintJobCost struct {
	Addr, SuggestedAddr                                         ShippingAddress
	AddrWarning                                                 ShippingAddressWarning
	Currency                                                    string
	Fees                                                        []Fee
	FulfillmentCost                                             FulfillmentCost
	LineItemCosts                                               []LineItemCost
	ShipCost                                                    FulfillmentCost
	TotalCostExclTax, TotalCostInclTax, TotalDiscount, TotalTax decimal.Decimal
}

type ShippingAddressWarning struct {
	Type string `json:"type"`    // eg "validation_warning"
	Path string `json:"path"`    // eg "external"
	Code string `json:"code"`    // eg "REPLACED"
	Msg  string `json:"message"` // eg "street1: Holstenstr. 40 -> Holstenstraße 40"
}

type Fee struct {
	Currency         string          `json:"currency"`
	Type             string          `json:"fee_type"`
	Sku              string          `json:"sku"`
	TaxRate          decimal.Decimal `json:"tax_rate"`
	TotalCostExclTax decimal.Decimal `json:"total_cost_excl_tax"`
	TotalCostInclTax decimal.Decimal `json:"total_cost_incl_tax"`
	TotalTax         decimal.Decimal `json:"total_tax"`
}

type FulfillmentCost struct {
	TaxRate          decimal.Decimal `json:"tax_rate"`
	TotalCostExclTax decimal.Decimal `json:"total_cost_excl_tax"`
	TotalCostInclTax decimal.Decimal `json:"total_cost_incl_tax"`
	TotalTax         decimal.Decimal `json:"total_tax"`
}

type LineItemCost struct {
	CostExclDiscounts      decimal.Decimal  `json:"cost_excl_discounts"`
	Discounts              []Discount       `json:"discounts"`
	Quantity               uint             `json:"quantity"`
	TaxRate                decimal.Decimal  `json:"tax_rate"`
	TotalCostExclDiscounts decimal.Decimal  `json:"total_cost_excl_discounts"`
	TotalCostExclTax       decimal.Decimal  `json:"total_cost_excl_tax"`
	TotalCostInclTax       decimal.Decimal  `json:"total_cost_incl_tax"`
	TotalTax               decimal.Decimal  `json:"total_tax"`
	UnitTierCost           *decimal.Decimal `json:"unit_tier_cost"`
}

type Discount struct {
	Amount decimal.Decimal `json:"amount"`
	Descr  string          `json:"description"`
}

// printJobCostResp is the json body of a /print-job-cost-calculations/ response.
type printJobCostResp struct {
	Addr struct {
		City        string                   `json:"city"`
		CountryCode string                   `json:"country_code"`
		IsBusiness  bool                     `json:"is_business"`
		Name        string                   `json:"name"`
		Phone       string                   `json:"phone_number"`
		PostCode    string                   `json:"postcode"`
		StateCode   string                   `json:"state_code"`
		Street1     string                   `json:"street1"`
		Street2     string                   `json:"street2"`
		Warning     ShippingAddressWarning   `json:"warnings"`
		Suggested   suggestedShippingAddress `json:"suggested_address"`
	} `json:"shipping_address"`
	Currency         string          `json:"currency"`
	Fees             []Fee           `json:"fees"`
	FulfillmentCost  FulfillmentCost `json:"fulfillment_cost"`
	LineItemCosts    []LineItemCost  `json:"line_item_costs"`
	ShipCost         FulfillmentCost `json:"shipping_cost"`
	TotalCostExclTax decimal.Decimal `json:"total_cost_excl_tax"`
	TotalCostInclTax decimal.Decimal `json:"total_cost_incl_tax"`
	TotalDiscount    decimal.Decimal `json:"total_discount_amount"`
	TotalTax         decimal.Decimal `json:"total_tax"`
}

// Some blockhead that Lulu hired thought it would be a good idea to use
// a string in one place and a number in another for the postal code.
// That's why this special struct is needed.
type suggestedShippingAddress struct {
	CountryCode string `json:"country_code"`
	StateCode   string `json:"state_code"`
	PostCode    uint   `json:"postcode"`
	City        string `json:"city"`
	Street1     string `json:"street1"`
	Street2     string `json:"street2"`
}

func (c *PrintJobCost) UnmarshalJSON(data []byte) error {
	// Lulu decided to put warnings and suggested_address INSIDE
	// shipping_address in the response. So we unmarshal into an
	// alias struct and then map onto our own structs. The
	// alternative is to add everything to our ShippingAddress
	// struct, but that would be confusing to users of this library:
	// ShippingAddress would have semantics because some fields would
	// be "optional".

	var resp printJobCostResp
	if err := json.Unmarshal(data, &resp); err != nil {
		return err
	}

	addr := resp.Addr
	c.Addr = ShippingAddress{
		City:        addr.City,
		CountryCode: addr.CountryCode,
		IsBusiness:  addr.IsBusiness,
		Name:        addr.Name,
		Phone:       addr.Phone,
		PostCode:    addr.PostCode,
		StateCode:   addr.StateCode,
		Street1:     addr.Street1,
		Street2:     addr.Street2,
	}
	sugad := addr.Suggested
	c.SuggestedAddr = ShippingAddress{
		CountryCode: sugad.CountryCode,
		StateCode:   sugad.StateCode,
		PostCode:    fmt.Sprint(sugad.PostCode), // idiot
		City:        sugad.City,
		Street1:     sugad.Street1,
		Street2:     sugad.Street2,
	}
	c.AddrWarning = addr.Warning

	c.Currency = resp.Currency
	c.Fees = resp.Fees
	c.FulfillmentCost = resp.FulfillmentCost
	c.LineItemCosts = resp.LineItemCosts
	c.ShipCost = resp.ShipCost
	c.TotalCostExclTax = resp.TotalCostExclTax
	c.TotalCostInclTax = resp.TotalCostInclTax
	c.TotalDiscount = resp.TotalDiscount
	c.TotalTax = resp.TotalTax

	return nil
}