package yookassa

import (
	"bytes"
	"context"
	"encoding/base64"
	"encoding/json"
	"fmt"
	"net/http"
	"time"

	"github.com/google/uuid"
	"github.com/shopspring/decimal"
)

type Client struct {
	shopID     string
	secretKey  string
	baseURL    string
	httpClient *http.Client
}

func NewClient(shopID, secretKey string) *Client {
	return &Client{
		shopID:     shopID,
		secretKey:  secretKey,
		baseURL:    "https://api.yookassa.ru/v3",
		httpClient: &http.Client{Timeout: 15 * time.Second},
	}
}

func (c *Client) CreatePayment(ctx context.Context, amount decimal.Decimal, description string, orderID uuid.UUID, returnURL string) (*PaymentResponse, error) {
	reqBody := PaymentRequest{
		Amount: Amount{
			Value:    amount.StringFixed(2),
			Currency: "RUB",
		},
		Capture: true, // Автоматическое списание
		Confirmation: Confirmation{
			Type:      "redirect",
			ReturnURL: returnURL,
		},
		Metadata: map[string]string{
			"order_id": orderID.String(),
		},
		Description: description,
	}

	body, _ := json.Marshal(reqBody)
	req, err := http.NewRequestWithContext(ctx, "POST", c.baseURL+"/payments", bytes.NewReader(body))
	if err != nil {
		return nil, err
	}

	// Basic Auth
	auth := base64.StdEncoding.EncodeToString([]byte(c.shopID + ":" + c.secretKey))
	req.Header.Set("Authorization", "Basic "+auth)
	req.Header.Set("Content-Type", "application/json")

	// Идемпотентность: используем наш order_id как ключ
	req.Header.Set("Idempotence-Key", orderID.String())

	resp, err := c.httpClient.Do(req)
	if err != nil {
		return nil, err
	}
	defer resp.Body.Close()

	if resp.StatusCode != http.StatusOK {
		return nil, fmt.Errorf("yookassa error: status %d", resp.StatusCode)
	}

	var result PaymentResponse
	if err := json.NewDecoder(resp.Body).Decode(&result); err != nil {
		return nil, err
	}

	return &result, nil
}