package woocommerce

import (
	"context"
	"encoding/json"
	"strconv"
	"time"
)

const (
	defaultListPerPage = 50
	maxListPerPage     = 100
)

type OrderBilling struct {
	Email     string `json:"email"`
	FirstName string `json:"first_name"`
	LastName  string `json:"last_name"`
}

type OrderLineItem struct {
	ID          int             `json:"id"`
	Name        string          `json:"name"`
	ProductID   int             `json:"product_id"`
	VariationID int             `json:"variation_id"`
	Quantity    int             `json:"quantity"`
	Total       string          `json:"total"`
	SKU         string          `json:"sku"`
	MetaData    json.RawMessage `json:"meta_data"`
}

type Order struct {
	ID         int             `json:"id"`
	Status     string          `json:"status"`
	Currency   string          `json:"currency"`
	Total      string          `json:"total"`
	CustomerID int             `json:"customer_id"`
	DateCreated string         `json:"date_created"`
	DateCreatedGMT string      `json:"date_created_gmt"`
	Billing    OrderBilling    `json:"billing"`
	LineItems  []OrderLineItem `json:"line_items"`
	Raw        json.RawMessage `json:"-"`
}

type ProductReview struct {
	ID           int             `json:"id"`
	ProductID    int             `json:"product_id"`
	Status       string          `json:"status"`
	Reviewer     string          `json:"reviewer"`
	ReviewerEmail string         `json:"reviewer_email"`
	Review       string          `json:"review"`
	Rating       int             `json:"rating"`
	DateCreated  string          `json:"date_created"`
	DateCreatedGMT string        `json:"date_created_gmt"`
	ProductName  string          `json:"product_name"`
	Raw          json.RawMessage `json:"-"`
}

func clampPerPage(perPage int) int {
	if perPage <= 0 {
		return defaultListPerPage
	}
	if perPage > maxListPerPage {
		return maxListPerPage
	}
	return perPage
}

// ListOrdersPage fetches one page of WooCommerce orders.
func (c *Client) ListOrdersPage(ctx context.Context, page, perPage int, modifiedAfter string) ([]Order, []byte, error) {
	perPage = clampPerPage(perPage)
	if page <= 0 {
		page = 1
	}
	q := map[string]string{
		"page":     strconv.Itoa(page),
		"per_page": strconv.Itoa(perPage),
		"orderby":  "date",
		"order":    "desc",
	}
	if modifiedAfter != "" {
		q["modified_after"] = modifiedAfter
	}
	raw, err := c.do(ctx, "GET", "/orders", q, nil)
	if err != nil {
		return nil, nil, err
	}
	var out []Order
	if err := json.Unmarshal(raw, &out); err != nil {
		return nil, nil, err
	}
	// Keep full payload slices aligned with unmarshaled rows.
	var rawItems []json.RawMessage
	_ = json.Unmarshal(raw, &rawItems)
	for i := range out {
		if i < len(rawItems) {
			out[i].Raw = rawItems[i]
		}
	}
	return out, raw, nil
}

// ListProductReviewsPage fetches one page of WooCommerce product reviews.
func (c *Client) ListProductReviewsPage(ctx context.Context, page, perPage int) ([]ProductReview, []byte, error) {
	perPage = clampPerPage(perPage)
	if page <= 0 {
		page = 1
	}
	q := map[string]string{
		"page":     strconv.Itoa(page),
		"per_page": strconv.Itoa(perPage),
		"orderby":  "date",
		"order":    "desc",
	}
	raw, err := c.do(ctx, "GET", "/products/reviews", q, nil)
	if err != nil {
		return nil, nil, err
	}
	var out []ProductReview
	if err := json.Unmarshal(raw, &out); err != nil {
		return nil, nil, err
	}
	var rawItems []json.RawMessage
	_ = json.Unmarshal(raw, &rawItems)
	for i := range out {
		if i < len(rawItems) {
			out[i].Raw = rawItems[i]
		}
	}
	return out, raw, nil
}

func parseWooTime(vals ...string) *time.Time {
	layouts := []string{
		time.RFC3339,
		"2006-01-02T15:04:05",
		"2006-01-02 15:04:05",
	}
	for _, v := range vals {
		if v == "" {
			continue
		}
		for _, layout := range layouts {
			if t, err := time.Parse(layout, v); err == nil {
				u := t.UTC()
				return &u
			}
		}
	}
	return nil
}