package handlers

import (
	"bytes"
	"context"
	"encoding/json"
	"errors"
	"net/http"
	"net/http/httptest"
	"testing"

	"git.threesix.ai/jordan/sp4-v2-1770499323/pkg/logging"
	"git.threesix.ai/jordan/sp4-v2-1770499323/services/chat-svc/internal/port"
)

// mockTaskProducer implements port.TaskProducer for testing.
type mockTaskProducer struct {
	lastAction  string
	lastPayload map[string]any
	jobID       string
	err         error
}

var _ port.TaskProducer = (*mockTaskProducer)(nil)

func (m *mockTaskProducer) EnqueueTask(ctx context.Context, action string, payload map[string]any) (string, error) {
	m.lastAction = action
	m.lastPayload = payload
	if m.err != nil {
		return "", m.err
	}
	return m.jobID, nil
}

func TestTask_Enqueue(t *testing.T) {
	tests := []struct {
		name       string
		body       any
		producer   *mockTaskProducer
		wantStatus int
		wantJobID  string
	}{
		{
			name: "valid request",
			body: EnqueueRequest{
				Action:  "send_notification",
				Payload: map[string]any{"user_id": "user-123", "message": "Hello"},
			},
			producer:   &mockTaskProducer{jobID: "job-456"},
			wantStatus: http.StatusAccepted,
			wantJobID:  "job-456",
		},
		{
			name:       "empty body",
			body:       nil,
			producer:   &mockTaskProducer{},
			wantStatus: http.StatusBadRequest,
		},
		{
			name: "producer error",
			body: EnqueueRequest{
				Action: "send_notification",
			},
			producer:   &mockTaskProducer{err: errors.New("queue unavailable")},
			wantStatus: http.StatusInternalServerError,
		},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			handler := NewTask(tt.producer, logging.Nop())

			var body []byte
			if tt.body != nil {
				var err error
				body, err = json.Marshal(tt.body)
				if err != nil {
					t.Fatalf("failed to marshal body: %v", err)
				}
			}

			req := httptest.NewRequest(http.MethodPost, "/api/chat-svc/tasks", bytes.NewReader(body))
			req.Header.Set("Content-Type", "application/json")
			w := httptest.NewRecorder()

			err := handler.Enqueue(w, req)
			if err != nil {
				if tt.wantStatus == http.StatusAccepted {
					t.Fatalf("unexpected error: %v", err)
				}
				return
			}

			if tt.wantStatus != http.StatusAccepted {
				t.Fatalf("expected error but got nil")
			}

			if w.Code != http.StatusAccepted {
				t.Errorf("expected status %d, got %d", http.StatusAccepted, w.Code)
			}

			var resp map[string]any
			if err := json.NewDecoder(w.Body).Decode(&resp); err != nil {
				t.Fatalf("failed to decode response: %v", err)
			}

			data, ok := resp["data"].(map[string]any)
			if !ok {
				t.Fatal("expected 'data' field in response")
			}

			if data["job_id"] != tt.wantJobID {
				t.Errorf("expected job_id %q, got %q", tt.wantJobID, data["job_id"])
			}
		})
	}
}