package web

import (
	"sync"
	"sync/atomic"
	"testing"
	"time"
)

func TestDashboardSnapshotCacheSharesConcurrentBuildAndInvalidates(t *testing.T) {
	cache := newDashboardSnapshotCache(time.Minute)
	var builds atomic.Int32
	build := func() (map[string]any, error) {
		builds.Add(1)
		time.Sleep(15 * time.Millisecond)
		return map[string]any{"ok": true}, nil
	}

	var wait sync.WaitGroup
	for range 12 {
		wait.Add(1)
		go func() {
			defer wait.Done()
			value, _, err := cache.Get("24h", build)
			if err != nil || value["ok"] != true {
				t.Errorf("Get returned value=%#v err=%v", value, err)
			}
		}()
	}
	wait.Wait()
	if got := builds.Load(); got != 1 {
		t.Fatalf("concurrent cache builds = %d, want 1", got)
	}

	cache.Invalidate()
	if _, hit, err := cache.Get("24h", build); err != nil || hit {
		t.Fatalf("invalidated cache returned hit=%v err=%v", hit, err)
	}
	if got := builds.Load(); got != 2 {
		t.Fatalf("builds after invalidation = %d, want 2", got)
	}
}