//go:build integration

package process

import (
	"errors"
	"strings"
	"testing"
	"time"

	"github.com/nats-io/nats.go"
	"github.com/nats-io/nats.go/jetstream"

	stdio "git.novox.be/novox/mesh-sdk/go"
)

// 1188/AC1: given a process connection to a test bus granted the bucket mesh-mail_sends, when it creates a
// key, reads it, and updates it with the revision it read, then each succeeds and returns the new
// revision; an update with a stale revision fails as stdio.ErrChanged; a create of an existing key fails
// as stdio.ErrChanged.
func TestStateCreateGetUpdateOnAGrantedBucket(t *testing.T) {
	url, account := grantedSendProcess(t)
	_, adminJetStream := adminJS(t, url)
	if _, err := adminJetStream.CreateKeyValue(ctxFor(t), jetstream.KeyValueConfig{Bucket: "mesh-mail_sends"}); err != nil {
		t.Fatalf("the admin could not make the bucket: %v", err)
	}

	conn, err := Connect(account)
	if err != nil {
		t.Fatal(err)
	}
	defer conn.Close()
	s := conn.State("sends")

	rev, err := s.Create("key", map[string]any{"v": 1})
	if err != nil {
		t.Fatalf("Create on a granted bucket: %v", err)
	}
	if rev == 0 {
		t.Fatal("Create returned no revision")
	}

	e, err := s.Get("key")
	if err != nil || e == nil {
		t.Fatalf("Get after Create: %+v, %v", e, err)
	}
	if e.Revision != rev || string(e.Value) != `{"v":1}` {
		t.Fatalf("Get read back %+v, want revision %d and {\"v\":1}", e, rev)
	}

	rev2, err := s.Update("key", map[string]any{"v": 2}, rev)
	if err != nil {
		t.Fatalf("Update at the revision read: %v", err)
	}
	if rev2 == rev {
		t.Fatal("Update did not return a new revision")
	}

	if _, err := s.Update("key", map[string]any{"v": 3}, rev); !errors.Is(err, stdio.ErrChanged) {
		t.Fatalf("Update at a stale revision: %v, want stdio.ErrChanged", err)
	}

	if _, err := s.Create("key", map[string]any{"v": 4}); !errors.Is(err, stdio.ErrChanged) {
		t.Fatalf("Create of an existing key: %v, want stdio.ErrChanged", err)
	}
}

// 1188/AC4: given an account not granted a bucket, when it writes there, then the bus's refusal comes
// back as an error naming the bucket. The bucket exists (made by the admin) so the only reason Create
// can fail is the missing grant, never "bucket not found"; and Conn's own ErrorHandler (conn.go
// withRefusal/publishRefused) catches the denied publish at once, so this returns promptly rather than
// after a timeout.
func TestStateRefusesAnUngrantedBucketNamingIt(t *testing.T) {
	url, account := grantedSendProcess(t)
	_, adminJetStream := adminJS(t, url)
	if _, err := adminJetStream.CreateKeyValue(ctxFor(t), jetstream.KeyValueConfig{Bucket: "mesh-mail_unrelated"}); err != nil {
		t.Fatalf("the admin could not make the bucket: %v", err)
	}

	conn, err := Connect(account)
	if err != nil {
		t.Fatal(err)
	}
	defer conn.Close()

	s := conn.State("unrelated")
	_, err = s.Create("key", map[string]any{"v": 1})
	if err == nil {
		t.Fatal("writing to an ungranted bucket was not refused")
	}
	if !errors.Is(err, nats.ErrPermissionViolation) {
		t.Errorf("the refusal %v does not wrap nats.ErrPermissionViolation", err)
	}
	if !strings.Contains(err.Error(), "mesh-mail_unrelated") {
		t.Errorf("the refusal %q does not name the bucket mesh-mail_unrelated", err.Error())
	}
}

// 1840/S1: given a process connection granted its bucket, when it puts keys whole and lists them, then Put
// returns a new revision each time and Keys lists them sorted (none for a bucket with none).
func TestStatePutAndKeysOnAGrantedBucket(t *testing.T) {
	url, account := grantedSendProcess(t)
	_, adminJetStream := adminJS(t, url)
	if _, err := adminJetStream.CreateKeyValue(ctxFor(t), jetstream.KeyValueConfig{Bucket: "mesh-mail_sends"}); err != nil {
		t.Fatalf("the admin could not make the bucket: %v", err)
	}
	conn, err := Connect(account)
	if err != nil {
		t.Fatal(err)
	}
	defer conn.Close()
	s := conn.State("sends")

	if keys, err := s.Keys(); err != nil || len(keys) != 0 {
		t.Fatalf("Keys of an empty bucket: %v, %v", keys, err)
	}
	rev, err := s.Put("b", map[string]any{"v": 1})
	if err != nil || rev == 0 {
		t.Fatalf("Put on a granted bucket: %d, %v", rev, err)
	}
	rev2, err := s.Put("b", map[string]any{"v": 2})
	if err != nil || rev2 <= rev {
		t.Fatalf("Put over a key: %d, %v", rev2, err)
	}
	if _, err := s.Put("a", 1); err != nil {
		t.Fatal(err)
	}
	keys, err := s.Keys()
	if err != nil || strings.Join(keys, ",") != "a,b" {
		t.Fatalf("Keys: %v, %v, want a,b", keys, err)
	}
}

// 1840/S2: given a process connection granted its bucket, which already holds two keys and a deleted one,
// when it watches, then it gets the two current values marked Current, and then a later put and a delete in
// order; a narrowed watch gets only the keys it names.
func TestStateWatchOnAGrantedBucket(t *testing.T) {
	url, account := grantedSendProcess(t)
	_, adminJetStream := adminJS(t, url)
	kv, err := adminJetStream.CreateKeyValue(ctxFor(t), jetstream.KeyValueConfig{Bucket: "mesh-mail_sends"})
	if err != nil {
		t.Fatalf("the admin could not make the bucket: %v", err)
	}
	ctx := ctxFor(t)
	for k, v := range map[string]string{"a.x": `1`, "a.y": `2`, "b.z": `3`, "gone": `4`} {
		if _, err := kv.Put(ctx, k, []byte(v)); err != nil {
			t.Fatal(err)
		}
	}
	if err := kv.Delete(ctx, "gone"); err != nil {
		t.Fatal(err)
	}
	conn, err := Connect(account)
	if err != nil {
		t.Fatal(err)
	}
	defer conn.Close()
	s := conn.State("sends")

	all := make(chan stdio.StateChange, 16)
	if err := s.Watch("", func(c stdio.StateChange) error { all <- c; return nil }); err != nil {
		t.Fatalf("Watch on a granted bucket: %v", err)
	}
	current := map[string]bool{}
	for len(all) > 0 {
		c := <-all
		if !c.Current || c.Op != "put" {
			t.Fatalf("a current value arrived as %+v", c)
		}
		current[c.Key] = true
	}
	if len(current) != 3 || current["gone"] {
		t.Fatalf("current values %v, want a.x, a.y, b.z and not gone", current)
	}

	narrow := make(chan stdio.StateChange, 16)
	if err := s.Watch("a.*", func(c stdio.StateChange) error { narrow <- c; return nil }); err != nil {
		t.Fatal(err)
	}
	if len(narrow) != 2 {
		t.Fatalf("a narrowed watch handed %d current values, want 2", len(narrow))
	}
	// the current values come in the order of their last revision, not of their keys: taken as a set.
	narrowCurrent := map[string]bool{}
	for len(narrow) > 0 {
		c := <-narrow
		if !c.Current || c.Op != "put" {
			t.Fatalf("a narrowed watch's current value arrived as %+v", c)
		}
		narrowCurrent[c.Key] = true
	}
	if !narrowCurrent["a.x"] || !narrowCurrent["a.y"] {
		t.Fatalf("a narrowed watch's current values %v, want a.x and a.y", narrowCurrent)
	}

	if _, err := s.Put("a.x", 5); err != nil {
		t.Fatal(err)
	}
	if err := kv.Delete(ctx, "a.y"); err != nil {
		t.Fatal(err)
	}
	for _, want := range []struct{ key, op string }{{"a.x", "put"}, {"a.y", "delete"}} {
		select {
		case c := <-all:
			if c.Key != want.key || c.Op != want.op || c.Current {
				t.Fatalf("got %+v, want %s %s, not current", c, want.op, want.key)
			}
		case <-time.After(10 * time.Second):
			t.Fatalf("no %s of %s", want.op, want.key)
		}
	}
	if _, err := s.Put("b.q", 6); err != nil {
		t.Fatal(err)
	}
	for _, want := range []string{"a.x", "a.y"} {
		select {
		case c := <-narrow:
			if c.Key != want || c.Current {
				t.Fatalf("narrowed watch got %+v, want the change of %s", c, want)
			}
		case <-time.After(10 * time.Second):
			t.Fatalf("narrowed watch missed %s", want)
		}
	}
	select {
	case c := <-narrow:
		t.Fatalf("narrowed watch got %+v for a key it did not name", c)
	case <-time.After(500 * time.Millisecond):
	}
}

// 1840/AC8: given an account not granted a bucket, when it watches it, then the refusal names the bucket.
func TestStateWatchRefusesAnUngrantedBucketNamingIt(t *testing.T) {
	url, account := grantedSendProcess(t)
	_, adminJetStream := adminJS(t, url)
	if _, err := adminJetStream.CreateKeyValue(ctxFor(t), jetstream.KeyValueConfig{Bucket: "mesh-mail_unrelated"}); err != nil {
		t.Fatalf("the admin could not make the bucket: %v", err)
	}
	conn, err := Connect(account)
	if err != nil {
		t.Fatal(err)
	}
	defer conn.Close()
	err = conn.State("unrelated").Watch("", func(stdio.StateChange) error { return nil })
	if err == nil || !errors.Is(err, nats.ErrPermissionViolation) || !strings.Contains(err.Error(), "mesh-mail_unrelated") {
		t.Fatalf("Watch on an ungranted bucket: %v, want a refusal naming mesh-mail_unrelated", err)
	}
}

// 1840/S1: given a process connection granted its bucket, when it deletes a key, then the key is gone and
// deleting it again is no error.
func TestStateDeleteOnAGrantedBucket(t *testing.T) {
	url, account := grantedSendProcess(t)
	_, adminJetStream := adminJS(t, url)
	if _, err := adminJetStream.CreateKeyValue(ctxFor(t), jetstream.KeyValueConfig{Bucket: "mesh-mail_sends"}); err != nil {
		t.Fatalf("the admin could not make the bucket: %v", err)
	}
	conn, err := Connect(account)
	if err != nil {
		t.Fatal(err)
	}
	defer conn.Close()
	s := conn.State("sends")
	if _, err := s.Put("k", 1); err != nil {
		t.Fatal(err)
	}
	if err := s.Delete("k"); err != nil {
		t.Fatalf("Delete on a granted bucket: %v", err)
	}
	if e, err := s.Get("k"); err != nil || e != nil {
		t.Fatalf("Get after Delete: %+v, %v", e, err)
	}
	if err := s.Delete("k"); err != nil {
		t.Fatalf("Delete of an absent key: %v", err)
	}
}