package api

import (
	"encoding/json"
	"net/http"
	"net/http/httptest"
	"strconv"
	"testing"

	"github.com/thepeterstone/claudomator/internal/event"
	"github.com/thepeterstone/claudomator/internal/task"
)

func TestListTaskEvents_ReturnsStreamInSeqOrder(t *testing.T) {
	srv, store := testServer(t)
	createTaskWithState(t, store, "ev-task", task.StateReady)

	req := httptest.NewRequest("GET", "/api/tasks/ev-task/events", nil)
	w := httptest.NewRecorder()
	srv.Handler().ServeHTTP(w, req)

	if w.Code != http.StatusOK {
		t.Fatalf("status: want 200, got %d; body %s", w.Code, w.Body.String())
	}
	var events []*event.Event
	if err := json.Unmarshal(w.Body.Bytes(), &events); err != nil {
		t.Fatalf("unmarshal: %v", err)
	}
	if len(events) == 0 {
		t.Fatal("expected state-change events from the walk to READY")
	}
	for i := 1; i < len(events); i++ {
		if events[i].Seq <= events[i-1].Seq {
			t.Errorf("events not in ascending seq order: %d then %d", events[i-1].Seq, events[i].Seq)
		}
	}
}

func TestListTaskEvents_SinceSeqFilters(t *testing.T) {
	srv, store := testServer(t)
	createTaskWithState(t, store, "ev-since", task.StateReady)

	all := getEvents(t, srv, "ev-since", "")
	if len(all) < 2 {
		t.Skipf("need at least 2 events to test since_seq, got %d", len(all))
	}
	firstSeq := all[0].Seq
	rest := getEvents(t, srv, "ev-since", "?since_seq="+itoa(firstSeq))
	for _, e := range rest {
		if e.Seq <= firstSeq {
			t.Errorf("since_seq=%d returned event with seq %d", firstSeq, e.Seq)
		}
	}
}

func TestListTaskEvents_NotFound(t *testing.T) {
	srv, _ := testServer(t)
	req := httptest.NewRequest("GET", "/api/tasks/missing/events", nil)
	w := httptest.NewRecorder()
	srv.Handler().ServeHTTP(w, req)
	if w.Code != http.StatusNotFound {
		t.Errorf("want 404, got %d", w.Code)
	}
}

func TestListTaskEvents_InvalidSinceSeq(t *testing.T) {
	srv, store := testServer(t)
	createTaskWithState(t, store, "ev-bad", task.StateReady)
	req := httptest.NewRequest("GET", "/api/tasks/ev-bad/events?since_seq=abc", nil)
	w := httptest.NewRecorder()
	srv.Handler().ServeHTTP(w, req)
	if w.Code != http.StatusBadRequest {
		t.Errorf("want 400, got %d", w.Code)
	}
}

func getEvents(t *testing.T, srv *Server, taskID, query string) []*event.Event {
	t.Helper()
	req := httptest.NewRequest("GET", "/api/tasks/"+taskID+"/events"+query, nil)
	w := httptest.NewRecorder()
	srv.Handler().ServeHTTP(w, req)
	if w.Code != http.StatusOK {
		t.Fatalf("getEvents %s%s: status %d", taskID, query, w.Code)
	}
	var events []*event.Event
	if err := json.Unmarshal(w.Body.Bytes(), &events); err != nil {
		t.Fatalf("getEvents unmarshal: %v", err)
	}
	return events
}

func itoa(n int64) string {
	return strconv.FormatInt(n, 10)
}