feat(models): 统一模型规格价格与路由

backend/internal/database/schema.go

@@ -1,9 +1,12 @@
 package database
 
 import (
+	"crypto/sha256"
 	"database/sql"
 	"errors"
 	"fmt"
+	"strconv"
+	"strings"
 
 	"infinite-canvas/backend/internal/model"
 
@@ -20,6 +23,7 @@ func Models() []any {
 		&model.EmailVerificationCode{},
 		&model.ModelChannel{},
 		&model.ChannelModel{},
+		&model.ChannelModelPriceTier{},
 		&model.IDSequence{},
 		&model.LogicalModel{},
 		&model.LogicalModelRevision{},
@@ -90,6 +94,15 @@ func MigrateSchema(db *gorm.DB) error {
 	if err := db.AutoMigrate(Models()...); err != nil {
 		return err
 	}
+	if err := migrateChannelModelPriceTierSelectors(db); err != nil {
+		return err
+	}
+	if err := backfillChannelModelPriceTiers(db); err != nil {
+		return err
+	}
+	if err := migrateChannelModelPriceTierSelectors(db); err != nil {
+		return err
+	}
 	if err := dropLegacyPhysicalVariants(db); err != nil {
 		return err
 	}
@@ -107,9 +120,113 @@ func MigrateSchema(db *gorm.DB) error {
 	if err := db.Exec("DROP INDEX IF EXISTS idx_route_attempt_task_number").Error; err != nil {
 		return err
 	}
+	if err := db.Exec("DROP INDEX IF EXISTS idx_logical_model_source_active").Error; err != nil {
+		return err
+	}
+	if err := db.Exec("CREATE UNIQUE INDEX IF NOT EXISTS idx_logical_model_source_active ON logical_models(source_channel_model_id) WHERE source_channel_model_id <> '' AND archived_at IS NULL").Error; err != nil {
+		return err
+	}
 	return db.Exec("CREATE UNIQUE INDEX IF NOT EXISTS idx_users_email_nonempty ON users(lower(email)) WHERE email <> ''").Error
 }
 
+// migrateChannelModelPriceTierSelectors upgrades the old video-only unique key to
+// a canonical SKU selector key. It never changes task, route-attempt, or billing
+// foreign keys, so completed work remains auditable after a product SKU merge.
+func migrateChannelModelPriceTierSelectors(db *gorm.DB) error {
+	if !db.Migrator().HasTable(&model.ChannelModelPriceTier{}) {
+		return nil
+	}
+	var tiers []model.ChannelModelPriceTier
+	if err := db.Unscoped().Find(&tiers).Error; err != nil {
+		return fmt.Errorf("读取规格价格档：%w", err)
+	}
+	for _, tier := range tiers {
+		selector := model.DecodeSKUSelector(tier.SelectorJSON)
+		if len(selector) == 0 {
+			selector = map[string]string{}
+			if resolution := strings.TrimSpace(tier.Resolution); resolution != "" && resolution != "*" {
+				selector["vquality"] = strings.ToLower(resolution)
+			}
+			if tier.VideoSeconds > 0 {
+				selector["videoSeconds"] = strconv.Itoa(tier.VideoSeconds)
+			}
+		}
+		_, key, err := model.CanonicalSKUSelector(selector)
+		if err != nil {
+			return fmt.Errorf("规范化规格价格档 %s：%w", tier.ID, err)
+		}
+		if tier.SelectorKey == key && tier.SelectorJSON == key {
+			continue
+		}
+		if err := db.Unscoped().Model(&model.ChannelModelPriceTier{}).Where("id = ?", tier.ID).Updates(map[string]any{"selector_key": key, "selector_json": key}).Error; err != nil {
+			return fmt.Errorf("更新规格价格档 %s：%w", tier.ID, err)
+		}
+	}
+	var duplicate struct {
+		ChannelModelID string
+		SelectorKey    string
+		Count          int64
+	}
+	err := db.Table("channel_model_price_tiers").
+		Select("channel_model_id, selector_key, COUNT(*) AS count").
+		Where("deleted_at IS NULL").
+		Group("channel_model_id, selector_key").
+		Having("COUNT(*) > 1").
+		First(&duplicate).Error
+	if err == nil {
+		return fmt.Errorf("渠道模型 %s 存在重复 SKU 选择器 %s，拒绝建立唯一索引", duplicate.ChannelModelID, duplicate.SelectorKey)
+	}
+	if !errors.Is(err, gorm.ErrRecordNotFound) {
+		return fmt.Errorf("检查重复 SKU 选择器：%w", err)
+	}
+	if err := db.Exec("DROP INDEX IF EXISTS idx_channel_model_price_tier_active").Error; err != nil {
+		return err
+	}
+	return db.Exec("CREATE UNIQUE INDEX IF NOT EXISTS idx_channel_model_price_tier_active ON channel_model_price_tiers(channel_model_id, selector_key) WHERE deleted_at IS NULL").Error
+}
+
+// backfillChannelModelPriceTiers 将旧的单价模型无损映射为默认价格档。历史订单保存的是
+// 金额快照，不能也不需要回写；这里仅保证升级后现有渠道模型仍能按原价格继续结算。
+func backfillChannelModelPriceTiers(db *gorm.DB) error {
+	var channelModels []model.ChannelModel
+	if err := db.Find(&channelModels).Error; err != nil {
+		return fmt.Errorf("读取渠道模型价格档回填数据：%w", err)
+	}
+	for _, channelModel := range channelModels {
+		var count int64
+		if err := db.Model(&model.ChannelModelPriceTier{}).Where("channel_model_id = ?", channelModel.ID).Count(&count).Error; err != nil {
+			return fmt.Errorf("检查渠道模型 %s 价格档：%w", channelModel.ID, err)
+		}
+		if count > 0 {
+			continue
+		}
+		priceVersion := channelModel.PriceVersion
+		if priceVersion < 1 {
+			priceVersion = 1
+		}
+		digest := sha256.Sum256([]byte(channelModel.ID))
+		tier := model.ChannelModelPriceTier{
+			ID:                           fmt.Sprintf("PTIER-%x", digest[:15]),
+			ChannelModelID:               channelModel.ID,
+			Resolution:                   "*",
+			VideoSeconds:                 0,
+			ProviderModelKey:             channelModel.ProviderModelKey,
+			BillingMode:                  channelModel.BillingMode,
+			UnitPriceMicrocredits:        channelModel.UnitPriceMicrocredits,
+			InputTokenPriceMicrocredits:  channelModel.InputTokenPriceMicrocredits,
+			OutputTokenPriceMicrocredits: channelModel.OutputTokenPriceMicrocredits,
+			CachedTokenPriceMicrocredits: channelModel.CachedTokenPriceMicrocredits,
+			PriceConfigured:              channelModel.PriceConfigured,
+			Enabled:                      channelModel.Enabled,
+			PriceVersion:                 priceVersion,
+		}
+		if err := db.Create(&tier).Error; err != nil {
+			return fmt.Errorf("回填渠道模型 %s 默认价格档：%w", channelModel.ID, err)
+		}
+	}
+	return nil
+}
+
 // migrateLogicalRoutesToChannelModels 在模型结构切换前把历史 variant 外键转换为渠道模型外键。
 // 写路径不能接受无法映射的历史引用，否则任务恢复和计费会失去明确执行目标。
 func migrateLogicalRoutesToChannelModels(db *gorm.DB) error {