feat: implement AI integration with backend configuration and rule-based enrichment actions

internal/actions/variants/set_variant.go

@@ -0,0 +1,60 @@
+package variants
+
+import (
+	"context"
+	"strings"
+	"time"
+
+	"git.pengzhan.dev/haopengzhan/rsspipe/internal/db"
+	"git.pengzhan.dev/haopengzhan/rsspipe/internal/models"
+	"git.pengzhan.dev/haopengzhan/rsspipe/internal/worker"
+)
+
+// NewSetVariantHandler creates a worker action handler for attaching extensible variant metadata.
+func NewSetVariantHandler(database *db.DB) worker.ActionHandler {
+	return func(ctx context.Context, entry models.FeedEntry, params map[string]interface{}) (*worker.ActionResult, error) {
+		key, _ := params["variant_key"].(string)
+		if key == "" {
+			key, _ = params["key"].(string)
+		}
+		if key == "" {
+			return nil, nil
+		}
+		val, _ := params["value"].(string)
+		contentType, _ := params["content_type"].(string)
+		if contentType == "" {
+			contentType = "text"
+		}
+
+		// If key == "tags", merge with existing tags so multiple rules append tags
+		if key == "tags" {
+			existingVariant, err := database.GetVariant(entry.ID, "tags")
+			if err == nil && existingVariant != nil && existingVariant.TextValue != "" {
+				existingTags := strings.Split(existingVariant.TextValue, ",")
+				newTags := strings.Split(val, ",")
+				tagSet := make(map[string]bool)
+				var merged []string
+				for _, t := range append(existingTags, newTags...) {
+					trimmed := strings.TrimSpace(t)
+					if trimmed != "" && !tagSet[strings.ToLower(trimmed)] {
+						tagSet[strings.ToLower(trimmed)] = true
+						merged = append(merged, trimmed)
+					}
+				}
+				val = strings.Join(merged, ", ")
+			}
+		}
+
+		variant := models.EntryVariant{
+			EntryID:     entry.ID,
+			VariantKey:  key,
+			ContentType: contentType,
+			TextValue:   val,
+			CreatedAt:   time.Now(),
+			UpdatedAt:   time.Now(),
+		}
+		return &worker.ActionResult{
+			ResultVariant: &variant,
+		}, nil
+	}
+}