Parse optional account_ids in run handler

internal/httpapi/run.go

@@ -1,8 +1,11 @@
 package httpapi
 
 import (
+	"bytes"
 	"context"
+	"encoding/json"
 	"errors"
+	"io"
 	"net/http"
 
 	"github.com/vasyansk/imap-copier/internal/crypto"
@@ -63,13 +66,41 @@ func (s *Server) handleTestAccounts(w http.ResponseWriter, r *http.Request) {
 	w.WriteHeader(http.StatusAccepted)
 }
 
+// parseRunAccountIDs reads an optional {"account_ids":[...]} run body. An empty
+// body means "all accounts" and yields a nil slice. Malformed JSON is an error.
+func parseRunAccountIDs(r *http.Request) ([]int64, error) {
+	raw, err := io.ReadAll(r.Body)
+	if err != nil {
+		return nil, err
+	}
+	if len(bytes.TrimSpace(raw)) == 0 {
+		return nil, nil
+	}
+	var body struct {
+		AccountIDs []int64 `json:"account_ids"`
+	}
+	if err := json.Unmarshal(raw, &body); err != nil {
+		return nil, err
+	}
+	return body.AccountIDs, nil
+}
+
 func (s *Server) handleRun(w http.ResponseWriter, r *http.Request) {
 	taskID, err := pathID(r, "id")
 	if err != nil {
 		http.Error(w, "bad id", http.StatusBadRequest)
 		return
 	}
-	runID, err := s.orch.Run(r.Context(), taskID, "manual", nil)
+	accountIDs, err := parseRunAccountIDs(r)
+	if err != nil {
+		http.Error(w, "bad request body", http.StatusBadRequest)
+		return
+	}
+	runID, err := s.orch.Run(r.Context(), taskID, "manual", accountIDs)
+	if errors.Is(err, orchestrator.ErrNoAccountsSelected) {
+		http.Error(w, "no matching accounts selected", http.StatusBadRequest)
+		return
+	}
 	if errors.Is(err, orchestrator.ErrNotTested) {
 		http.Error(w, "accounts must pass connection tests first", http.StatusConflict)
 		return