package graph

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

	"github.com/local/glpi-neural-brain/internal/model"
)

func TestResearchTaskLifecycleSQLite(t *testing.T) {
	store, err := Open(t.TempDir())
	if err != nil {
		t.Fatal(err)
	}
	defer store.Close()
	ctx := context.Background()
	request := model.ResearchTask{
		DedupeKey:   "zfs-restore",
		Topic:       "ZFS Restore",
		Reason:      "missing_validation",
		RequestedBy: "test",
		Priority:    .91,
		Questions:   []string{"Wie wird ein Restore validiert?"},
		MaxAttempts: 3,
	}
	queued, created, err := store.EnqueueResearchTask(ctx, request, 24*time.Hour)
	if err != nil || !created {
		t.Fatalf("enqueue created=%t err=%v", created, err)
	}
	duplicate, created, err := store.EnqueueResearchTask(ctx, request, 24*time.Hour)
	if err != nil || created || duplicate.ID != queued.ID {
		t.Fatalf("dedupe created=%t original=%s duplicate=%s err=%v", created, queued.ID, duplicate.ID, err)
	}
	leased, ok, err := store.LeaseNextResearchTask(ctx, .65, 30*time.Minute)
	if err != nil || !ok || leased.ID != queued.ID || leased.Status != "reserved" || leased.Attempts != 1 {
		t.Fatalf("lease ok=%t task=%+v err=%v", ok, leased, err)
	}
	if err := store.MarkResearchTaskRunning(ctx, leased.ID); err != nil {
		t.Fatal(err)
	}
	leased.EvidenceCount = 3
	leased.ArticleCreated = true
	leased.ArticleTitle = "ZFS Restore validieren"
	leased.Outcome = "article_created"
	if err := store.CompleteResearchTask(ctx, leased); err != nil {
		t.Fatal(err)
	}
	completed, err := store.GetResearchTask(ctx, leased.ID)
	if err != nil {
		t.Fatal(err)
	}
	if completed.Status != "completed" || completed.EvidenceCount != 3 || !completed.ArticleCreated || completed.CompletedAt.IsZero() {
		t.Fatalf("unexpected completed task: %+v", completed)
	}
	counts, err := store.ResearchTaskCounts(ctx)
	if err != nil || counts["completed"] != 1 {
		t.Fatalf("unexpected counts=%v err=%v", counts, err)
	}
}

func TestResearchTaskFailureDefersUntilMaxAttempts(t *testing.T) {
	store, err := Open(t.TempDir())
	if err != nil {
		t.Fatal(err)
	}
	defer store.Close()
	ctx := context.Background()
	queued, _, err := store.EnqueueResearchTask(ctx, model.ResearchTask{Topic: "Btrfs Timeline", Priority: .8, MaxAttempts: 2}, 0)
	if err != nil {
		t.Fatal(err)
	}
	leased, ok, err := store.LeaseNextResearchTask(ctx, 0, 30*time.Minute)
	if err != nil || !ok {
		t.Fatalf("lease ok=%t err=%v", ok, err)
	}
	leased.LastError = "temporary"
	leased.Outcome = "failed"
	if err := store.FailResearchTask(ctx, leased, time.Millisecond); err != nil {
		t.Fatal(err)
	}
	first, err := store.GetResearchTask(ctx, queued.ID)
	if err != nil || first.Status != "deferred" {
		t.Fatalf("expected deferred task, got %+v err=%v", first, err)
	}
	time.Sleep(3 * time.Millisecond)
	leased, ok, err = store.LeaseNextResearchTask(ctx, 0, 30*time.Minute)
	if err != nil || !ok {
		t.Fatalf("second lease ok=%t err=%v", ok, err)
	}
	leased.LastError = "permanent"
	leased.Outcome = "failed"
	if err := store.FailResearchTask(ctx, leased, 0); err != nil {
		t.Fatal(err)
	}
	final, err := store.GetResearchTask(ctx, queued.ID)
	if err != nil || final.Status != "failed" || final.Attempts != 2 {
		t.Fatalf("expected failed task after max attempts, got %+v err=%v", final, err)
	}
}

func TestResearchTaskConcurrentEnqueueDeduplicates(t *testing.T) {
	store, err := Open(t.TempDir())
	if err != nil {
		t.Fatal(err)
	}
	defer store.Close()
	ctx := context.Background()
	request := model.ResearchTask{DedupeKey: "same-search", Topic: "Same SearXNG task", Questions: []string{"same question"}, Priority: .8}

	var created atomic.Int64
	var wg sync.WaitGroup
	errs := make(chan error, 16)
	for i := 0; i < 16; i++ {
		wg.Add(1)
		go func() {
			defer wg.Done()
			_, wasCreated, enqueueErr := store.EnqueueResearchTask(ctx, request, time.Hour)
			if enqueueErr != nil {
				errs <- enqueueErr
				return
			}
			if wasCreated {
				created.Add(1)
			}
		}()
	}
	wg.Wait()
	close(errs)
	for err := range errs {
		t.Fatal(err)
	}
	if got := created.Load(); got != 1 {
		t.Fatalf("expected exactly one created task, got %d", got)
	}
	tasks, err := store.ListResearchTasks(ctx, 100)
	if err != nil {
		t.Fatal(err)
	}
	if len(tasks) != 1 {
		t.Fatalf("expected exactly one queued task, got %d: %+v", len(tasks), tasks)
	}
}