package payment

import (
	"context"
	"crypto/sha256"
	"encoding/hex"
	"encoding/json"
	"errors"
	"fmt"
	"net/url"
	"strconv"
	"strings"

	"kra/internal/biz"
	datapayment "kra/internal/integration/payment"

	"gorm.io/gorm"
)

type paymentRepo struct{ data Provider }

func NewPaymentRepo(data Provider) biz.PaymentRepo { return &paymentRepo{data: data} }

func ensurePaymentIntegrationConfigs(db *gorm.DB) error {
	for _, provider := range biz.SupportedPaymentProviders {
		var row integrationConfigPO
		err := db.Where("kind = ? AND provider = ?", integrationKindPayment, provider).First(&row).Error
		defaults := biz.DefaultIntegrationConfig(integrationKindPayment, provider)
		if errors.Is(err, gorm.ErrRecordNotFound) {
			encoded, _ := json.Marshal(defaults)
			if err := db.Create(&integrationConfigPO{Kind: integrationKindPayment, Provider: provider, Enabled: false, Config: string(encoded)}).Error; err != nil {
				return err
			}
			continue
		}
		if err != nil {
			return err
		}
		values := map[string]any{}
		_ = json.Unmarshal([]byte(row.Config), &values)
		changed := false
		for key, value := range defaults {
			if _, exists := values[key]; !exists {
				values[key] = value
				changed = true
			}
		}
		if changed {
			encoded, _ := json.Marshal(values)
			if err := db.Model(&row).Update("config", string(encoded)).Error; err != nil {
				return err
			}
		}
	}
	return nil
}

func (r *paymentRepo) row(ctx context.Context, provider string) (*integrationConfigPO, map[string]any, error) {
	var row integrationConfigPO
	if err := r.data.DB().WithContext(ctx).Where("kind = ? AND provider = ?", integrationKindPayment, provider).First(&row).Error; err != nil {
		if errors.Is(err, gorm.ErrRecordNotFound) {
			return nil, nil, biz.ErrPaymentProviderNotFound
		}
		return nil, nil, err
	}
	if !row.Enabled {
		return nil, nil, fmt.Errorf("支付渠道 %s 未启用", provider)
	}
	values := map[string]any{}
	if err := json.Unmarshal([]byte(row.Config), &values); err != nil {
		return nil, nil, fmt.Errorf("支付配置格式错误: %w", err)
	}
	return &row, values, nil
}

func (r *paymentRepo) adapter(ctx context.Context, provider string) (datapayment.Adapter, map[string]any, error) {
	_, values, err := r.row(ctx, provider)
	if err != nil {
		return nil, nil, err
	}
	adapter, err := datapayment.New(provider)
	return adapter, values, err
}

func (r *paymentRepo) Create(ctx context.Context, req *biz.PaymentRequest) (*biz.PaymentResult, error) {
	if req == nil {
		return nil, errors.New("支付下单请求为空")
	}
	a, c, err := r.adapter(ctx, req.Provider)
	if err != nil {
		return nil, err
	}
	effective := *req
	effective.NotifyURL = strings.TrimSpace(text(c, "notify_url"))
	effective.ReturnURL = strings.TrimSpace(text(c, "return_url"))
	if paymentCreateRequiresNotifyURL(req.Provider, req.Extra, c) && effective.NotifyURL == "" {
		return nil, fmt.Errorf("支付渠道 %s 未配置服务端 notify_url", req.Provider)
	}
	return a.Create(ctx, &effective, c)
}

func paymentProviderRequiresNotifyURL(provider string) bool {
	switch provider {
	case biz.PaymentApple, biz.PaymentAllinPay, biz.PaymentSaobei, biz.PaymentPayPal:
		return false
	default:
		return true
	}
}

// paymentCreateRequiresNotifyURL keeps the repository-level URL guard aligned
// with the selected provider operation. Synchronous barcode/retail APIs return
// their execution result directly and do not consume notify_url; redirect and
// client-side prepay APIs still require the configured server callback URL.
func paymentCreateRequiresNotifyURL(provider string, extra, config map[string]any) bool {
	if !paymentProviderRequiresNotifyURL(provider) {
		return false
	}
	keys := []string{"method", "pay_method", "trade_type", "pay_type", "channel"}
	switch provider {
	case biz.PaymentAlipay, biz.PaymentAlipayV3:
		keys = []string{"method", "pay_method", "trade_type", "channel"}
	case biz.PaymentWechatV2:
		keys = []string{"trade_type", "pay_type", "method", "pay_method", "channel"}
	case biz.PaymentWechatV3:
		keys = []string{"trade_type", "pay_type", "method"}
	case biz.PaymentQQ:
		keys = []string{"trade_type", "pay_type", "method", "pay_method"}
	case biz.PaymentLakala:
		keys = []string{"method", "pay_method", "trade_type"}
	}
	value := firstAny(extra, keys...)
	if value == "" {
		value = firstAny(config, keys...)
	}
	normalized := strings.NewReplacer(".", "_", "-", "_", " ", "_").Replace(strings.ToLower(strings.TrimSpace(value)))
	switch provider {
	case biz.PaymentAlipay, biz.PaymentAlipayV3:
		return !contains([]string{"pay", "trade_pay", "alipay_trade_pay", "barcode", "barcode_pay", "micropay", "face_to_face"}, normalized)
	case biz.PaymentWechatV2:
		return !contains([]string{"micropay", "micro_pay", "barcode", "barcode_pay", "pay_code", "payment_code"}, normalized)
	case biz.PaymentWechatV3:
		return !contains([]string{"micropay", "micro_pay", "codepay", "code_pay", "barcode", "barcode_pay", "facepay", "face_pay"}, normalized)
	case biz.PaymentQQ:
		return !contains([]string{"micropay", "micro_pay", "barcode", "barcode_pay"}, normalized)
	case biz.PaymentLakala:
		return !contains([]string{"retail", "retail_pay", "micropay", "barcode"}, normalized)
	default:
		return true
	}
}
func (r *paymentRepo) Query(ctx context.Context, provider, tradeNo string) (*biz.PaymentResult, error) {
	a, c, err := r.adapter(ctx, provider)
	if err != nil {
		return nil, err
	}
	return a.Query(ctx, tradeNo, c)
}
func (r *paymentRepo) Refund(ctx context.Context, req *biz.PaymentRefundRequest) (*biz.PaymentResult, error) {
	if req == nil {
		return nil, errors.New("支付退款请求为空")
	}
	a, c, err := r.adapter(ctx, req.Provider)
	if err != nil {
		return nil, err
	}
	return a.Refund(ctx, req, c)
}
func (r *paymentRepo) HandleCallback(ctx context.Context, callback *biz.PaymentCallback) (*biz.PaymentResult, error) {
	if callback == nil {
		return nil, errors.New("支付回调为空")
	}
	a, c, err := r.adapter(ctx, callback.Provider)
	if err != nil {
		return nil, err
	}
	result, err := a.Callback(ctx, callback, c)
	if err != nil {
		return nil, &biz.PaymentCallbackError{Cause: err, Ack: paymentCallbackAck(callback.Provider, c, false)}
	}
	if result == nil {
		err = errors.New("支付回调解析结果为空")
		return nil, &biz.PaymentCallbackError{Cause: err, Ack: paymentCallbackAck(callback.Provider, c, false)}
	}
	result.SuccessAck = paymentCallbackAck(callback.Provider, c, true)
	result.FailureAck = paymentCallbackAck(callback.Provider, c, false)
	if result.Provider != callback.Provider {
		err = errors.New("支付回调渠道不匹配")
		return nil, &biz.PaymentCallbackError{Cause: err, Ack: result.FailureAck}
	}
	result.EventID = paymentCallbackEventID(callback, result)
	return result, nil
}

func paymentCallbackEventID(callback *biz.PaymentCallback, result *biz.PaymentResult) string {
	if result != nil {
		if eventID := strings.TrimSpace(result.EventID); eventID != "" {
			return eventID
		}
	}
	if callback == nil {
		return ""
	}
	fields := callbackFields(callback)
	if eventID := strings.TrimSpace(first(fields, "event_id", "notify_id", "notificationUUID", "id")); eventID != "" {
		return eventID
	}
	hash := sha256.Sum256(append([]byte(callback.Provider+"\x00"), callback.Body...))
	return hex.EncodeToString(hash[:])
}

func paymentCallbackAck(provider string, values map[string]any, success bool) biz.PaymentCallbackAck {
	ack := biz.DefaultPaymentCallbackAck(provider, success)
	prefix := "callback_success_"
	if !success {
		prefix = "callback_failure_"
	}
	if configured := strings.TrimSpace(text(values, prefix+"status")); configured != "" {
		if status, err := strconv.Atoi(configured); err == nil && status >= 200 && status <= 599 {
			ack.StatusCode = status
		}
	}
	if contentType := strings.TrimSpace(text(values, prefix+"content_type")); contentType != "" {
		ack.ContentType = contentType
	}
	if body, exists := values[prefix+"body"]; exists {
		ack.Body = []byte(fmt.Sprint(body))
	}
	return ack
}

func callbackFields(callback *biz.PaymentCallback) map[string]string {
	fields := map[string]string{}
	for key, value := range callback.Query {
		fields[key] = value
	}
	contentType := strings.ToLower(callback.Headers["Content-Type"])
	if strings.Contains(contentType, "application/x-www-form-urlencoded") {
		if values, err := url.ParseQuery(string(callback.Body)); err == nil {
			for key, value := range values {
				if len(value) > 0 {
					fields[key] = value[0]
				}
			}
		}
	}
	var object map[string]any
	if json.Unmarshal(callback.Body, &object) == nil {
		for key, value := range object {
			if text, ok := value.(string); ok {
				fields[key] = text
			}
		}
	}
	return fields
}

func first(values map[string]string, keys ...string) string {
	for _, key := range keys {
		if values[key] != "" {
			return values[key]
		}
	}
	return ""
}

func contains(values []string, value string) bool {
	for _, item := range values {
		if item == value {
			return true
		}
	}
	return false
}

func validatePaymentConfig(provider string, values map[string]any) error {
	return biz.ValidateIntegrationConfig(biz.IntegrationKindPayment, provider, values)
}