package ociindex

import (
	"encoding/json"
	"os"
	"path/filepath"
	"testing"

	digest "github.com/opencontainers/go-digest"
	ocispecs "github.com/opencontainers/image-spec/specs-go/v1"
	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/require"
)

func TestEmptyDir(t *testing.T) {
	dir := t.TempDir()
	store := NewStoreIndex(dir)
	idx, err := store.Read()
	require.Error(t, err)
	assert.Nil(t, idx)
	assert.ErrorIs(t, err, os.ErrNotExist)
}

func TestReadIndex(t *testing.T) {
	dir := t.TempDir()
	idx := ocispecs.Index{
		Manifests: []ocispecs.Descriptor{
			randDescriptor("foo"),
		},
	}
	dt, err := json.Marshal(idx)
	require.NoError(t, err)
	err = os.WriteFile(filepath.Join(dir, "index.json"), dt, 0644)
	require.NoError(t, err)

	store := NewStoreIndex(dir)
	readIdx, err := store.Read()
	require.NoError(t, err)
	assert.Len(t, readIdx.Manifests, 1)

	assert.Equal(t, idx.Manifests[0], readIdx.Manifests[0])
}

func TestReadByTag(t *testing.T) {
	dir := t.TempDir()

	one := randDescriptor("foo")
	two := randDescriptor("bar")
	three := randDescriptor("baz")

	const refName = "org.opencontainers.image.ref.name"

	two.Annotations = map[string]string{
		refName: "ver1",
	}
	three.Annotations = map[string]string{
		refName: "ver2",
	}

	idx := ocispecs.Index{
		Manifests: []ocispecs.Descriptor{
			one,
			two,
			three,
		},
	}
	dt, err := json.Marshal(idx)
	require.NoError(t, err)
	err = os.WriteFile(filepath.Join(dir, "index.json"), dt, 0644)
	require.NoError(t, err)

	store := NewStoreIndex(dir)
	desc, err := store.Get("ver1")
	require.NoError(t, err)

	assert.Equal(t, *desc, two)

	desc, err = store.Get("ver3")
	require.NoError(t, err)
	assert.Nil(t, desc)
}

func TestWriteSingleDescriptor(t *testing.T) {
	dir := t.TempDir()
	store := NewStoreIndex(dir)

	desc := randDescriptor("foo")
	err := store.Put(desc)
	require.NoError(t, err)

	readDesc, err := store.GetSingle()
	require.NoError(t, err)
	assert.Equal(t, desc, *readDesc)
}

func TestAddDescriptor(t *testing.T) {
	dir := t.TempDir()

	one := randDescriptor("foo")
	two := randDescriptor("bar")

	idx := ocispecs.Index{
		Manifests: []ocispecs.Descriptor{
			one,
			two,
		},
	}
	dt, err := json.Marshal(idx)
	require.NoError(t, err)

	err = os.WriteFile(filepath.Join(dir, "index.json"), dt, 0644)
	require.NoError(t, err)

	store := NewStoreIndex(dir)
	three := randDescriptor("baz")
	err = store.Put(three)
	require.NoError(t, err)

	readIdx, err := store.Read()
	require.NoError(t, err)

	assert.Len(t, readIdx.Manifests, 3)
	assert.Equal(t, one, readIdx.Manifests[0])
	assert.Equal(t, two, readIdx.Manifests[1])
	assert.Equal(t, three, readIdx.Manifests[2])

	// store.Put also sets defaults for MediaType and SchemaVersion
	assert.Equal(t, ocispecs.MediaTypeImageIndex, readIdx.MediaType)
	assert.Equal(t, 2, readIdx.SchemaVersion)
}

func TestAddDescriptorWithTag(t *testing.T) {
	dir := t.TempDir()

	one := randDescriptor("foo")
	two := randDescriptor("bar")

	idx := ocispecs.Index{
		Manifests: []ocispecs.Descriptor{
			one,
			two,
		},
	}
	dt, err := json.Marshal(idx)
	require.NoError(t, err)

	err = os.WriteFile(filepath.Join(dir, "index.json"), dt, 0644)
	require.NoError(t, err)

	store := NewStoreIndex(dir)
	three := randDescriptor("baz")
	err = store.Put(three, Tag("ver1"))
	require.NoError(t, err)

	desc, err := store.Get("ver1")
	require.NoError(t, err)

	assert.Equal(t, three.Digest, desc.Digest)
	assert.Equal(t, three.Size, desc.Size)
	assert.Equal(t, three.MediaType, desc.MediaType)

	assert.Equal(t, "ver1", desc.Annotations["org.opencontainers.image.ref.name"])

	readIdx, err := store.Read()
	require.NoError(t, err)

	assert.Len(t, readIdx.Manifests, 3)
	assert.Equal(t, one, readIdx.Manifests[0])
	assert.Equal(t, two, readIdx.Manifests[1])
	assert.Equal(t, *desc, readIdx.Manifests[2])
}

func TestAddMultipleNames(t *testing.T) {
	dir := t.TempDir()

	store := NewStoreIndex(dir)

	one := randDescriptor("foo")
	err := store.Put(one, Name("app/name:v1"), Name("app/name:v1.0"), Name("app/other:latest"))
	require.NoError(t, err)

	var idx ocispecs.Index
	dt, err := os.ReadFile(filepath.Join(dir, "index.json"))
	require.NoError(t, err)

	err = json.Unmarshal(dt, &idx)
	require.NoError(t, err)

	require.Len(t, idx.Manifests, 3)

	require.Equal(t, one.Digest, idx.Manifests[0].Digest)
	require.Equal(t, one.Size, idx.Manifests[0].Size)
	require.Equal(t, one.MediaType, idx.Manifests[0].MediaType)

	require.Equal(t, "v1", idx.Manifests[0].Annotations["org.opencontainers.image.ref.name"])
	require.Equal(t, "app/name:v1", idx.Manifests[0].Annotations["io.containerd.image.name"])

	require.Equal(t, one.Digest, idx.Manifests[1].Digest)
	require.Equal(t, one.Size, idx.Manifests[1].Size)
	require.Equal(t, one.MediaType, idx.Manifests[1].MediaType)

	require.Equal(t, "v1.0", idx.Manifests[1].Annotations["org.opencontainers.image.ref.name"])
	require.Equal(t, "app/name:v1.0", idx.Manifests[1].Annotations["io.containerd.image.name"])

	require.Equal(t, one.Digest, idx.Manifests[2].Digest)
	require.Equal(t, one.Size, idx.Manifests[2].Size)
	require.Equal(t, one.MediaType, idx.Manifests[1].MediaType)

	require.Equal(t, "latest", idx.Manifests[2].Annotations["org.opencontainers.image.ref.name"])
	require.Equal(t, "app/other:latest", idx.Manifests[2].Annotations["io.containerd.image.name"])

	desc, err := store.Get("app/name:v1")
	require.NoError(t, err)
	require.NotNil(t, desc)

	require.Equal(t, one.Digest, desc.Digest)
	require.Equal(t, one.Size, desc.Size)
	require.Equal(t, one.MediaType, desc.MediaType)

	require.Equal(t, "v1", desc.Annotations["org.opencontainers.image.ref.name"])
	require.Equal(t, "app/name:v1", desc.Annotations["io.containerd.image.name"])
}

func TestReplaceByImageName(t *testing.T) {
	dir := t.TempDir()

	strore := NewStoreIndex(dir)
	one := randDescriptor("foo")
	two := randDescriptor("bar")
	three := randDescriptor("baz")

	err := strore.Put(one)
	require.NoError(t, err)

	err = strore.Put(two, Name("app/name:v1"))
	require.NoError(t, err)

	err = strore.Put(three, Name("app/name:v2"))
	require.NoError(t, err)

	// replace by image name
	four := randDescriptor("qux")
	err = strore.Put(four, Name("app/name:v1"))
	require.NoError(t, err)

	readIdx, err := strore.Read()
	require.NoError(t, err)

	assert.Len(t, readIdx.Manifests, 3)

	assert.Equal(t, one, readIdx.Manifests[0])

	assert.Equal(t, three.Digest, readIdx.Manifests[1].Digest)
	assert.Equal(t, three.Size, readIdx.Manifests[1].Size)
	assert.Equal(t, three.MediaType, readIdx.Manifests[1].MediaType)

	assert.Equal(t, "v2", readIdx.Manifests[1].Annotations["org.opencontainers.image.ref.name"])
	assert.Equal(t, "app/name:v2", readIdx.Manifests[1].Annotations["io.containerd.image.name"])

	assert.Equal(t, four.Digest, readIdx.Manifests[2].Digest)
	assert.Equal(t, four.Size, readIdx.Manifests[2].Size)
	assert.Equal(t, four.MediaType, readIdx.Manifests[2].MediaType)

	assert.Equal(t, "v1", readIdx.Manifests[2].Annotations["org.opencontainers.image.ref.name"])
	assert.Equal(t, "app/name:v1", readIdx.Manifests[2].Annotations["io.containerd.image.name"])
}

func randDescriptor(seed string) ocispecs.Descriptor {
	dgst := digest.FromBytes([]byte(seed))
	return ocispecs.Descriptor{
		MediaType: "application/vnd.test.descriptor+json",
		Digest:    dgst,
		Size:      int64(len(seed)),
	}
}