package listing

import (
	"context"
	"encoding/json"
	"fmt"
	"math"
	"strconv"
	"strings"
	"time"
)

func (s *Service) ImportExternalUpload(ctx context.Context, req ExternalUploadRequest, meta ExternalUploadMeta) (*ExternalUploadResponse, error) {
	if s.repo == nil {
		return nil, ErrDependencyUnavailable
	}
	uploaderName := req.normalizedUploaderName()
	if uploaderName == "" {
		return nil, ErrMissingUploaderName
	}
	items, err := parseExternalUploadItems(req.Data)
	if err != nil {
		return nil, err
	}
	if len(items) > maxExternalUploadItems {
		return nil, ErrTooManyUploadItems
	}
	rules, err := s.publishRules(ctx)
	if err != nil {
		return nil, err
	}
	clientUploadTime := parseClientUploadTime(req.UploadTime)
	results := make([]ExternalUploadResult, 0, len(items))
	resp := &ExternalUploadResponse{Total: len(items)}
	for index, item := range items {
		createReq := externalAccountToCreateRequest(uploaderName, req.UploadTime, item)
		if err := validateRequest(createReq, rules); err != nil {
			if len(items) == 1 {
				return nil, err
			}
			resp.Failed++
			results = append(results, ExternalUploadResult{Index: index, Error: err.Error()})
			continue
		}
		parsedPayload, _ := json.Marshal(item)
		dto, err := s.repo.CreateFromExternalUpload(ctx, externalUploadCreate{
			UploaderName:     uploaderName,
			ClientUploadTime: clientUploadTime,
			ClientIP:         meta.IP,
			RawPayload:       meta.RawPayload,
			ParsedPayload:    parsedPayload,
		}, createReq)
		if err != nil {
			if len(items) == 1 {
				return nil, err
			}
			resp.Failed++
			results = append(results, ExternalUploadResult{Index: index, Error: err.Error()})
			continue
		}
		resp.Success++
		result := ExternalUploadResult{
			Index:                      index,
			ListingID:                  dto.ID,
			ListingNo:                  dto.ListingNo,
			AccountID:                  dto.AccountID,
			ListingGroupConversationID: dto.ListingGroupConversationID,
			Status:                     dto.Status,
			ReviewStatus:               dto.ReviewStatus,
		}
		results = append(results, result)
		if len(items) == 1 {
			resp.ListingID = dto.ID
			resp.ListingNo = dto.ListingNo
			resp.AccountID = dto.AccountID
			resp.ListingGroupConversationID = dto.ListingGroupConversationID
			resp.Status = dto.Status
			resp.ReviewStatus = dto.ReviewStatus
		}
	}
	resp.Items = results
	if resp.Success == 0 && resp.Failed > 0 {
		return resp, ErrInvalidInput
	}
	return resp, nil
}

func parseExternalUploadItems(raw json.RawMessage) ([]ExternalAccountData, error) {
	if len(raw) == 0 || strings.TrimSpace(string(raw)) == "" || string(raw) == "null" {
		return nil, ErrMissingUploadData
	}
	var singleRaw map[string]json.RawMessage
	if err := json.Unmarshal(raw, &singleRaw); err == nil {
		if err := validateExternalUploadRaw(singleRaw, "data"); err != nil {
			return nil, err
		}
		var single ExternalAccountData
		if err := json.Unmarshal(raw, &single); err != nil {
			return nil, ErrMissingUploadData
		}
		return []ExternalAccountData{single}, nil
	}
	var rawItems []json.RawMessage
	if err := json.Unmarshal(raw, &rawItems); err != nil {
		return nil, ErrMissingUploadData
	}
	if len(rawItems) == 0 {
		return nil, ErrMissingUploadData
	}
	items := make([]ExternalAccountData, 0, len(rawItems))
	for index, rawItem := range rawItems {
		var rawMap map[string]json.RawMessage
		if err := json.Unmarshal(rawItem, &rawMap); err != nil {
			return nil, UploadValidationError{Invalid: []string{fmt.Sprintf("data[%d]", index)}}
		}
		prefix := fmt.Sprintf("data[%d]", index)
		if err := validateExternalUploadRaw(rawMap, prefix); err != nil {
			return nil, err
		}
		var item ExternalAccountData
		if err := json.Unmarshal(rawItem, &item); err != nil {
			return nil, UploadValidationError{Invalid: []string{prefix}}
		}
		items = append(items, item)
	}
	return items, nil
}

func validateExternalUploadRaw(raw map[string]json.RawMessage, prefix string) error {
	var validation UploadValidationError
	requireStringField(raw, prefix, "loginMethod", &validation)
	requireStringField(raw, prefix, "rank", &validation)
	requireNumberField(raw, prefix, "level", &validation)
	requireNumberField(raw, prefix, "safeSlots", &validation)
	requireNumberField(raw, prefix, "secretKD", &validation)
	requireNumberField(raw, prefix, "deposit", &validation)
	requireNumberField(raw, prefix, "dailyLossM", &validation)

	currency := requireObjectField(raw, prefix, "currency", &validation)
	requireNumberField(currency, prefix+".currency", "hafuCoin", &validation)
	requireNumberField(currency, prefix+".currency", "recycleRatio", &validation)
	requireNumberField(currency, prefix+".currency", "recycleRent", &validation)

	dailyConsumption := requireObjectField(raw, prefix, "dailyConsumption", &validation)
	requireNumberField(dailyConsumption, prefix+".dailyConsumption", "stamina", &validation)
	requireNumberField(dailyConsumption, prefix+".dailyConsumption", "weight", &validation)

	if len(validation.Missing) > 0 || len(validation.Invalid) > 0 {
		return validation
	}
	return nil
}

func requireObjectField(raw map[string]json.RawMessage, prefix string, field string, validation *UploadValidationError) map[string]json.RawMessage {
	if raw == nil {
		validation.Missing = append(validation.Missing, prefix+"."+field)
		return nil
	}
	value, ok := raw[field]
	if !ok || isJSONNull(value) {
		validation.Missing = append(validation.Missing, prefix+"."+field)
		return nil
	}
	var object map[string]json.RawMessage
	if err := json.Unmarshal(value, &object); err != nil {
		validation.Invalid = append(validation.Invalid, prefix+"."+field)
		return nil
	}
	return object
}

func requireStringField(raw map[string]json.RawMessage, prefix string, field string, validation *UploadValidationError) {
	value, ok := raw[field]
	if !ok || isJSONNull(value) {
		validation.Missing = append(validation.Missing, prefix+"."+field)
		return
	}
	var text string
	if err := json.Unmarshal(value, &text); err != nil {
		validation.Invalid = append(validation.Invalid, prefix+"."+field)
		return
	}
	if strings.TrimSpace(text) == "" {
		validation.Missing = append(validation.Missing, prefix+"."+field)
	}
}

func requireNumberField(raw map[string]json.RawMessage, prefix string, field string, validation *UploadValidationError) {
	if raw == nil {
		validation.Missing = append(validation.Missing, prefix+"."+field)
		return
	}
	value, ok := raw[field]
	if !ok || isJSONNull(value) {
		validation.Missing = append(validation.Missing, prefix+"."+field)
		return
	}
	var number json.Number
	decoder := json.NewDecoder(strings.NewReader(string(value)))
	decoder.UseNumber()
	if err := decoder.Decode(&number); err != nil {
		validation.Invalid = append(validation.Invalid, prefix+"."+field)
	}
}

func isJSONNull(value json.RawMessage) bool {
	return strings.TrimSpace(string(value)) == "null"
}

func parseClientUploadTime(value int64) *time.Time {
	if value <= 0 {
		return nil
	}
	if value > 1_000_000_000_000 {
		parsed := time.UnixMilli(value)
		return &parsed
	}
	parsed := time.Unix(value, 0)
	return &parsed
}

func externalAccountToCreateRequest(uploaderName string, uploadTime int64, item ExternalAccountData) CreateRequest {
	hafCoinM := item.Currency.HafuCoin
	price := item.Currency.RecycleRent
	ratio := item.Currency.RecycleRatio
	insurance := insuranceFromSafeSlots(item.SafeSlots)
	staminaLevel := levelText(item.DailyConsumption.Stamina)
	loadLevel := levelText(item.DailyConsumption.Weight)
	skins := cleanStrings(item.Inventory.Skins)
	assetSummary := map[string]any{
		"face_owner":       "",
		"secret_kd":        item.SecretKD,
		"fire_level":       item.Level,
		"daily_loss_m":     item.DailyLossM,
		"publish_ratio":    ratio,
		"season_insurance": insurance,
		"stamina_level":    staminaLevel,
		"load_level":       loadLevel,
		"resources":        externalResources(item.Inventory),
		"skin_groups":      externalSkinGroups(skins),
		"online_time_text": strings.TrimSpace(item.OwnerOnlineTime),
		"ban_record":       normalizeBanRecord(item.BanRecord),
		"common_regions":   commonRegions(item.CommonRegion),
		"remark":           "开放接口自动上传，等待后台审核。",
		"import_meta": map[string]any{
			"uploader_name":      uploaderName,
			"client_upload_time": uploadTime,
			"contact_phone":      strings.TrimSpace(item.ContactPhone),
		},
		"price_breakdown": map[string]any{
			"seller_reference_ratio": ratio,
			"seller_ratio":           ratio,
			"seller_coin_base_price": price,
			"seller_total_price":     price,
			"consumable_price":       consumableValue(map[string]any{"resources": externalResources(item.Inventory)}),
			"buyer_coin_base_price":  price,
			"buyer_total_price":      price,
			"buyer_ratio":            ratio,
			"platform_markup_amount": 0,
			"platform_rule_type":     "external_upload",
		},
	}
	return CreateRequest{
		Title:             externalUploadTitle(item, insurance, hafCoinM),
		Description:       "开放接口自动上传，等待后台审核。",
		ServerRegion:      serverRegionFromLoginMethod(item.LoginMethod),
		LoginPlatform:     strings.TrimSpace(item.LoginMethod),
		RankLevel:         strings.TrimSpace(item.Rank),
		HafCoinAmount:     int64(math.Round(hafCoinM * 1000000)),
		AssetSummary:      assetSummary,
		ScreenshotURLS:    []string{defaultUploadScreenshot},
		PriceCent:         yuanToCent(price),
		DepositAmountCent: yuanToCent(item.Deposit),
	}
}

func externalUploadTitle(item ExternalAccountData, insurance string, hafCoinM float64) string {
	parts := []string{
		strings.TrimSpace(item.Rank),
		insurance,
		fmt.Sprintf("%.1fM", hafCoinM),
		strings.TrimSpace(item.LoginMethod),
	}
	title := strings.TrimSpace(strings.Join(cleanStrings(parts), " "))
	if title == "" {
		return "开放接口上传账号"
	}
	if len([]rune(title)) > 128 {
		return string([]rune(title)[:128])
	}
	return title
}

func serverRegionFromLoginMethod(value string) string {
	value = strings.TrimSpace(value)
	switch {
	case strings.Contains(value, "微信"):
		return "微信"
	case strings.Contains(strings.ToLower(value), "steam"):
		return "Steam"
	default:
		return "QQ"
	}
}

func insuranceFromSafeSlots(value int) string {
	switch value {
	case 9:
		return "3*3"
	case 6:
		return "2*3"
	case 4:
		return "2*2"
	case 2:
		return "2*1"
	default:
		if value > 0 {
			return strconv.Itoa(value) + "格"
		}
		return ""
	}
}

func levelText(value int) string {
	if value <= 0 {
		return ""
	}
	return strconv.Itoa(value) + "级"
}

func externalResources(inventory ExternalUploadInventory) []any {
	resources := []any{
		map[string]any{"key": "awmAmmo", "label": "AWM子弹", "price": "0.6元/发", "quantity": inventory.AWMBullets, "mode": "收费"},
		map[string]any{"key": "helmet6", "label": "6头", "price": "1.5元/个", "quantity": inventory.Level6Helmets, "mode": "收费"},
		map[string]any{"key": "armor6", "label": "6甲", "price": "2.5元/个", "quantity": inventory.Level6Armor, "mode": "收费"},
	}
	return resources
}

func externalSkinGroups(skins []string) map[string][]string {
	groups := map[string][]string{
		"melee":    {},
		"imported": {},
	}
	for _, skin := range skins {
		switch skin {
		case "坠星者", "暗星", "龙牙", "信条", "怜悯", "赤枭", "影锋", "黑海", "北极星", "电锯惊魂", "处刑者":
			groups["melee"] = append(groups["melee"], skin)
		default:
			groups["imported"] = append(groups["imported"], skin)
		}
	}
	return groups
}

func normalizeBanRecord(value string) string {
	value = strings.TrimSpace(value)
	switch value {
	case "", "无", "无封禁", "无封禁记录":
		return "无封禁记录"
	default:
		return value
	}
}

func commonRegions(value string) []string {
	return cleanStrings(strings.Split(value, ","))
}

func cleanStrings(values []string) []string {
	result := make([]string, 0, len(values))
	seen := make(map[string]struct{}, len(values))
	for _, value := range values {
		value = strings.TrimSpace(value)
		if value == "" {
			continue
		}
		if _, ok := seen[value]; ok {
			continue
		}
		seen[value] = struct{}{}
		result = append(result, value)
	}
	return result
}
