package dataobj

import (
	"math"
	"testing"

	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/require"

	"github.com/grafana/loki/v3/pkg/dataobj/internal/metadata/filemd"
	"github.com/grafana/loki/v3/pkg/scratch"
)

func Test_encoder_typeRefs(t *testing.T) {
	tt := []struct {
		name  string
		input SectionType

		expectRef     uint32
		expectNameRef *filemd.SectionType_NameRef
	}{
		{
			name:  "invalid",
			input: SectionType{},

			expectRef:     0,
			expectNameRef: nil,
		},
		{
			name: "streams",
			input: SectionType{
				Namespace: "github.com/grafana/loki",
				Kind:      "streams",
			},

			expectRef:     1,
			expectNameRef: &filemd.SectionType_NameRef{NamespaceRef: 1, KindRef: 2},
		},
		{
			name: "logs",
			input: SectionType{
				Namespace: "github.com/grafana/loki",
				Kind:      "logs",
			},

			expectRef:     2,
			expectNameRef: &filemd.SectionType_NameRef{NamespaceRef: 1, KindRef: 3},
		},
		{
			name: "existing namespace, new kind",
			input: SectionType{
				Namespace: "github.com/grafana/loki",
				Kind:      "section-kind-1",
			},

			expectRef:     3,
			expectNameRef: &filemd.SectionType_NameRef{NamespaceRef: 1, KindRef: 4},
		},
		{
			name: "existing namespace, existing kind",
			input: SectionType{
				Namespace: "github.com/grafana/loki",
				Kind:      "section-kind-1",
			},

			expectRef:     3,
			expectNameRef: &filemd.SectionType_NameRef{NamespaceRef: 1, KindRef: 4},
		},
		{
			name: "new namespace, existing kind",
			input: SectionType{
				Namespace: "new-namespace",
				Kind:      "section-kind-1",
			},

			expectRef:     4,
			expectNameRef: &filemd.SectionType_NameRef{NamespaceRef: 5, KindRef: 4},
		},
		{
			name: "new namespace, new kind",
			input: SectionType{
				Namespace: "new-namespace-2",
				Kind:      "section-kind-2",
			},

			expectRef:     5,
			expectNameRef: &filemd.SectionType_NameRef{NamespaceRef: 6, KindRef: 7},
		},
		{
			name: "existing type, new version",
			input: SectionType{
				Namespace: "github.com/grafana/loki",
				Kind:      "streams",
				Version:   math.MaxUint32,
			},

			expectRef:     6,
			expectNameRef: &filemd.SectionType_NameRef{NamespaceRef: 1, KindRef: 2},
		},
	}

	enc := newEncoder(scratch.NewMemory())

	// Test are run sequentially so we can check the behaviour of streaming types
	// in.
	for _, tc := range tt {
		typeRef := enc.getTypeRef(tc.input)
		nameRef := enc.rawTypes[typeRef].NameRef

		assert.Equal(t, tc.expectRef, typeRef, "unexpected type ref for %s", tc.name)
		assert.Equal(t, tc.expectNameRef, nameRef, "unexpected name ref for %s", tc.name)
	}

}

func Test_encoder_ObjectSize(t *testing.T) {
	store := scratch.NewMemory()
	enc := newEncoder(store)

	var (
		sectionType = SectionType{
			Namespace: "github.com/grafana/loki",
			Kind:      "test",
		}

		data     = []byte("test data content")
		metadata = []byte("test metadata")
	)

	enc.AppendSection(sectionType, nil, data, metadata)

	snapshot, err := enc.Flush()
	assert.NoError(t, err)
	defer snapshot.Close()

	computedMetadata, err := enc.Metadata()
	require.NoError(t, err)
	require.Greater(t, computedMetadata.ObjectSize, int64(0), "ObjectSize should be greater than zero")
	require.Equal(t, snapshot.Size(), computedMetadata.ObjectSize, "ObjectSize in metadata should match the actual encoded snapshot size")
}