//
// Copyright (c) 2018
// Mainflux
//
// SPDX-License-Identifier: Apache-2.0
//

package postgres_test

import (
	"fmt"
	"testing"

	"github.com/stretchr/testify/require"

	"github.com/mainflux/mainflux/things"
	"github.com/mainflux/mainflux/things/postgres"
	"github.com/mainflux/mainflux/things/uuid"
	"github.com/stretchr/testify/assert"
)

func TestThingSave(t *testing.T) {
	email := "thing-save@example.com"
	thingRepo := postgres.NewThingRepository(db, testLog)

	thing := things.Thing{
		ID:    uuid.New().ID(),
		Owner: email,
		Key:   uuid.New().ID(),
	}

	cases := []struct {
		desc  string
		thing things.Thing
		err   error
	}{
		{
			desc:  "create new thing",
			thing: thing,
			err:   nil,
		},
		{
			desc: "create invalid thing",
			thing: things.Thing{
				ID:       uuid.New().ID(),
				Owner:    email,
				Key:      uuid.New().ID(),
				Metadata: "invalid",
			},
			err: things.ErrMalformedEntity,
		},
	}

	for _, tc := range cases {
		_, err := thingRepo.Save(tc.thing)
		assert.Equal(t, tc.err, err, fmt.Sprintf("%s: expected %s got %s\n", tc.desc, tc.err, err))
	}
}

func TestThingUpdate(t *testing.T) {
	email := "thing-update@example.com"
	thingRepo := postgres.NewThingRepository(db, testLog)

	thing := things.Thing{
		ID:    uuid.New().ID(),
		Owner: email,
		Key:   uuid.New().ID(),
	}

	id, _ := thingRepo.Save(thing)
	thing.ID = id

	cases := []struct {
		desc  string
		thing things.Thing
		err   error
	}{
		{
			desc:  "update existing thing",
			thing: thing,
			err:   nil,
		},
		{
			desc: "update non-existing thing with existing user",
			thing: things.Thing{
				ID:    uuid.New().ID(),
				Owner: email,
			},
			err: things.ErrNotFound,
		},
		{
			desc: "update existing thing ID with non-existing user",
			thing: things.Thing{
				ID:    id,
				Owner: wrongValue,
			},
			err: things.ErrNotFound,
		},
		{
			desc: "update non-existing thing with non-existing user",
			thing: things.Thing{
				ID:    uuid.New().ID(),
				Owner: wrongValue,
			},
			err: things.ErrNotFound,
		},
		{
			desc: "update thing with invalid data",
			thing: things.Thing{
				ID:       id,
				Owner:    email,
				Metadata: "invalid",
			},
			err: things.ErrMalformedEntity,
		},
	}

	for _, tc := range cases {
		err := thingRepo.Update(tc.thing)
		assert.Equal(t, tc.err, err, fmt.Sprintf("%s: expected %s got %s\n", tc.desc, tc.err, err))
	}
}

func TestSingleThingRetrieval(t *testing.T) {
	email := "thing-single-retrieval@example.com"
	thingRepo := postgres.NewThingRepository(db, testLog)

	thing := things.Thing{
		ID:    uuid.New().ID(),
		Owner: email,
		Key:   uuid.New().ID(),
	}

	id, _ := thingRepo.Save(thing)
	thing.ID = id

	cases := map[string]struct {
		owner string
		ID    string
		err   error
	}{
		"retrieve thing with existing user": {
			owner: thing.Owner,
			ID:    thing.ID,
			err:   nil,
		},
		"retrieve non-existing thing with existing user": {
			owner: thing.Owner,
			ID:    uuid.New().ID(),
			err:   things.ErrNotFound,
		},
		"retrieve thing with non-existing owner": {
			owner: wrongValue,
			ID:    thing.ID,
			err:   things.ErrNotFound,
		},
	}

	for desc, tc := range cases {
		_, err := thingRepo.RetrieveByID(tc.owner, tc.ID)
		assert.Equal(t, tc.err, err, fmt.Sprintf("%s: expected %s got %s\n", desc, tc.err, err))
	}
}

func TestThingRetrieveByKey(t *testing.T) {
	email := "thing-retrieved-by-key@example.com"
	thingRepo := postgres.NewThingRepository(db, testLog)

	thing := things.Thing{
		ID:    uuid.New().ID(),
		Owner: email,
		Key:   uuid.New().ID(),
	}

	id, _ := thingRepo.Save(thing)
	thing.ID = id

	cases := map[string]struct {
		key string
		ID  string
		err error
	}{
		"retrieve existing thing by key": {
			key: thing.Key,
			ID:  thing.ID,
			err: nil,
		},
		"retrieve non-existent thing by key": {
			key: wrongValue,
			ID:  "",
			err: things.ErrNotFound,
		},
	}

	for desc, tc := range cases {
		id, err := thingRepo.RetrieveByKey(tc.key)
		assert.Equal(t, tc.ID, id, fmt.Sprintf("%s: expected %s got %s\n", desc, tc.ID, id))
		assert.Equal(t, tc.err, err, fmt.Sprintf("%s: expected %s got %s\n", desc, tc.err, err))
	}
}

func TestMultiThingRetrieval(t *testing.T) {
	email := "thing-multi-retrieval@example.com"
	idp := uuid.New()
	thingRepo := postgres.NewThingRepository(db, testLog)

	n := uint64(10)

	for i := uint64(0); i < n; i++ {
		t := things.Thing{
			ID:    uuid.New().ID(),
			Owner: email,
			Key:   idp.ID(),
		}

		thingRepo.Save(t)
	}

	cases := map[string]struct {
		owner  string
		offset uint64
		limit  uint64
		size   uint64
	}{
		"retrieve all things with existing owner": {
			owner:  email,
			offset: 0,
			limit:  n,
			size:   n,
		},
		"retrieve subset of things with existing owner": {
			owner:  email,
			offset: n / 2,
			limit:  n,
			size:   n / 2,
		},
		"retrieve things with non-existing owner": {
			owner:  wrongValue,
			offset: 0,
			limit:  n,
			size:   0,
		},
	}

	for desc, tc := range cases {
		result := thingRepo.RetrieveAll(tc.owner, tc.offset, tc.limit)
		size := uint64(len(result))
		assert.Equal(t, tc.size, size, fmt.Sprintf("%s: expected %d got %d\n", desc, tc.size, size))
	}
}

func TestThingRemoval(t *testing.T) {
	email := "thing-removal@example.com"
	thingRepo := postgres.NewThingRepository(db, testLog)

	thing := things.Thing{
		ID:    uuid.New().ID(),
		Owner: email,
		Key:   uuid.New().ID(),
	}

	id, _ := thingRepo.Save(thing)
	thing.ID = id

	// show that the removal works the same for both existing and non-existing
	// (removed) thing
	for i := 0; i < 2; i++ {
		err := thingRepo.Remove(email, thing.ID)
		require.Nil(t, err, fmt.Sprintf("#%d: failed to remove thing due to: %s", i, err))

		_, err = thingRepo.RetrieveByID(email, thing.ID)
		require.Equal(t, things.ErrNotFound, err, fmt.Sprintf("#%d: expected %s got %s", i, things.ErrNotFound, err))
	}
}