package gateway

import (
	"context"
	"net/http"
	"testing"

	"git.yeij.top/AskaEth/Cyrene_v2/internal/auth"
	"git.yeij.top/AskaEth/Cyrene_v2/internal/runtime/history"
)

// TestHistorySessionsLastMessage asserts the GET /api/v1/sessions wire contract for the
// last-message preview (B3): every session carries lastMessage {role,content,createdAt}
// with the newest message's whitespace-collapsed content, and a message-less session
// omits the field.
func TestHistorySessionsLastMessage(t *testing.T) {
	t.Parallel()
	_, ts, jwt, st := newHistoryEnv(t)
	ctx := context.Background()
	if err := st.Append(ctx, history.Message{SessionID: history.MainSessionID, Role: history.RoleUser, Content: "你好", CreatedAt: 1000}); err != nil {
		t.Fatalf("seed user: %v", err)
	}
	if err := st.Append(ctx, history.Message{SessionID: history.MainSessionID, Role: history.RoleAssistant, Content: "  在的\n请说  ", CreatedAt: 2000}); err != nil {
		t.Fatalf("seed assistant: %v", err)
	}
	sub, err := st.NewSubSession(ctx, "owner")
	if err != nil {
		t.Fatalf("new sub: %v", err)
	}
	tok := signAny(t, jwt, "acct", auth.RoleOwner)

	resp, body := doReq(t, http.MethodGet, ts.URL+"/api/v1/sessions", nil, tok)
	if resp.StatusCode != http.StatusOK {
		t.Fatalf("status = %d, want 200 (body=%s)", resp.StatusCode, body)
	}
	// Decode into a JSON-tagged shape so the wire contract (key names) is asserted,
	// not just the in-package struct.
	var sessions []struct {
		ID          string `json:"id"`
		LastMessage *struct {
			Role      string `json:"role"`
			Content   string `json:"content"`
			CreatedAt int64  `json:"createdAt"`
		} `json:"lastMessage"`
	}
	decodeDataSlice(t, body, &sessions)
	if len(sessions) != 2 || sessions[0].ID != history.MainSessionID {
		t.Fatalf("sessions = %+v, want main first", sessions)
	}
	main := sessions[0].LastMessage
	if main == nil || main.Role != history.RoleAssistant || main.Content != "在的 请说" || main.CreatedAt != 2000 {
		t.Fatalf("main lastMessage = %+v, want assistant/在的 请说/2000", main)
	}
	// The empty sub session omits lastMessage entirely.
	if sessions[1].ID != sub {
		t.Fatalf("sessions[1].id = %q, want %q", sessions[1].ID, sub)
	}
	if sessions[1].LastMessage != nil {
		t.Fatalf("empty sub lastMessage = %+v, want omitted", sessions[1].LastMessage)
	}
}