package elasticsearch

import (
	"fmt"
	"github.com/google/go-cmp/cmp"
	"github.com/json-iterator/go"
	"io/ioutil"
	"kubesphere.io/kubesphere/pkg/simple/client/logging"
	"kubesphere.io/kubesphere/pkg/simple/client/logging/elasticsearch/versions/v5"
	"kubesphere.io/kubesphere/pkg/simple/client/logging/elasticsearch/versions/v6"
	"kubesphere.io/kubesphere/pkg/simple/client/logging/elasticsearch/versions/v7"
	"net/http"
	"net/http/httptest"
	"testing"
)

func TestInitClient(t *testing.T) {
	var tests = []struct {
		fakeResp string
		expected string
	}{
		{
			fakeResp: "es6_detect_version_major_200.json",
			expected: ElasticV6,
		},
		{
			fakeResp: "es7_detect_version_major_200.json",
			expected: ElasticV7,
		},
	}

	for i, test := range tests {
		t.Run(fmt.Sprintf("%d", i), func(t *testing.T) {
			es := mockElasticsearchService("/", test.fakeResp, http.StatusOK)
			defer es.Close()

			client := &Elasticsearch{host: es.URL}
			err := client.loadClient()
			if err != nil {
				t.Fatal(err)
			}

			if diff := cmp.Diff(client.version, test.expected); diff != "" {
				t.Fatalf("%T differ (-got, +want): %s", test.expected, diff)
			}
		})
	}
}

func TestGetCurrentStats(t *testing.T) {
	var tests = []struct {
		fakeVersion string
		fakeResp    string
		fakeCode    int
		expected    logging.Statistics
		expectedErr string
	}{
		{
			fakeVersion: ElasticV6,
			fakeResp:    "es6_get_current_stats_200.json",
			fakeCode:    http.StatusOK,
			expected: logging.Statistics{
				Containers: 93,
				Logs:       241222,
			},
		},
		{
			fakeVersion: ElasticV6,
			fakeResp:    "es6_get_current_stats_404.json",
			fakeCode:    http.StatusNotFound,
			expectedErr: "type: index_not_found_exception, reason: no such index",
		},
		{
			fakeVersion: ElasticV7,
			fakeResp:    "es7_get_current_stats_200.json",
			fakeCode:    http.StatusOK,
			expected: logging.Statistics{
				Containers: 48,
				Logs:       9726,
			},
		},
		{
			fakeVersion: ElasticV7,
			fakeResp:    "es7_get_current_stats_404.json",
			fakeCode:    http.StatusNotFound,
			expectedErr: "type: index_not_found_exception, reason: no such index [ks-logstash-log-2020.05.2]",
		},
	}

	for i, test := range tests {
		t.Run(fmt.Sprintf("%d", i), func(t *testing.T) {
			srv := mockElasticsearchService("/ks-logstash-log*/_search", test.fakeResp, test.fakeCode)
			defer srv.Close()

			es := newElasticsearchClient(srv, test.fakeVersion)

			result, err := es.GetCurrentStats(logging.SearchFilter{})
			if test.expectedErr != "" {
				if diff := cmp.Diff(fmt.Sprint(err), test.expectedErr); diff != "" {
					t.Fatalf("%T differ (-got, +want): %s", test.expectedErr, diff)
				}
			}
			if diff := cmp.Diff(result, test.expected); diff != "" {
				t.Fatalf("%T differ (-got, +want): %s", test.expected, diff)
			}
		})
	}
}

func TestCountLogsByInterval(t *testing.T) {
	var tests = []struct {
		fakeVersion string
		fakeResp    string
		fakeCode    int
		expected    logging.Histogram
		expectedErr string
	}{
		{
			fakeVersion: ElasticV7,
			fakeResp:    "es7_count_logs_by_interval_200.json",
			fakeCode:    http.StatusOK,
			expected: logging.Histogram{
				Total: 10000,
				Buckets: []logging.Bucket{
					{
						Time:  1589644800000,
						Count: 410,
					},
					{
						Time:  1589646600000,
						Count: 7465,
					},
					{
						Time:  1589648400000,
						Count: 12790,
					},
				},
			},
		},
		{
			fakeVersion: ElasticV7,
			fakeResp:    "es7_count_logs_by_interval_400.json",
			fakeCode:    http.StatusBadRequest,
			expectedErr: "type: search_phase_execution_exception, reason: all shards failed",
		},
		{
			fakeVersion: ElasticV7,
			fakeResp:    "es7_count_logs_by_interval_404.json",
			fakeCode:    http.StatusNotFound,
			expectedErr: "type: index_not_found_exception, reason: no such index [ks-logstash-log-20]",
		},
	}

	for i, test := range tests {
		t.Run(fmt.Sprintf("%d", i), func(t *testing.T) {
			srv := mockElasticsearchService("/ks-logstash-log*/_search", test.fakeResp, test.fakeCode)
			defer srv.Close()

			es := newElasticsearchClient(srv, test.fakeVersion)

			result, err := es.CountLogsByInterval(logging.SearchFilter{}, "15m")
			if test.expectedErr != "" {
				if diff := cmp.Diff(fmt.Sprint(err), test.expectedErr); diff != "" {
					t.Fatalf("%T differ (-got, +want): %s", test.expectedErr, diff)
				}
			}
			if diff := cmp.Diff(result, test.expected); diff != "" {
				t.Fatalf("%T differ (-got, +want): %s", test.expected, diff)
			}
		})
	}
}

func TestSearchLogs(t *testing.T) {
	var tests = []struct {
		fakeVersion string
		fakeResp    string
		fakeCode    int
		expected    string
		expectedErr string
	}{
		{
			fakeVersion: ElasticV7,
			fakeResp:    "es7_search_logs_200.json",
			fakeCode:    http.StatusOK,
			expected:    "es7_search_logs_200_result.json",
		},
	}

	for i, test := range tests {
		t.Run(fmt.Sprintf("%d", i), func(t *testing.T) {
			var expected logging.Logs
			err := JsonFromFile(test.expected, &expected)
			if err != nil {
				t.Fatal(err)
			}

			srv := mockElasticsearchService("/ks-logstash-log*/_search", test.fakeResp, test.fakeCode)
			defer srv.Close()

			es := newElasticsearchClient(srv, test.fakeVersion)

			result, err := es.SearchLogs(logging.SearchFilter{}, 0, 10, "asc")
			if test.expectedErr != "" {
				if diff := cmp.Diff(fmt.Sprint(err), test.expectedErr); diff != "" {
					t.Fatalf("%T differ (-got, +want): %s", test.expectedErr, diff)
				}
			}
			if diff := cmp.Diff(result, expected); diff != "" {
				t.Fatalf("%T differ (-got, +want): %s", expected, diff)
			}
		})
	}
}

func mockElasticsearchService(pattern, fakeResp string, fakeCode int) *httptest.Server {
	mux := http.NewServeMux()
	mux.HandleFunc(pattern, func(res http.ResponseWriter, req *http.Request) {
		b, _ := ioutil.ReadFile(fmt.Sprintf("./testdata/%s", fakeResp))
		res.WriteHeader(fakeCode)
		res.Write(b)
	})
	return httptest.NewServer(mux)
}

func newElasticsearchClient(srv *httptest.Server, version string) *Elasticsearch {
	es := &Elasticsearch{index: "ks-logstash-log"}
	switch version {
	case ElasticV5:
		es.c, _ = v5.New(srv.URL, "ks-logstash-log")
	case ElasticV6:
		es.c, _ = v6.New(srv.URL, "ks-logstash-log")
	case ElasticV7:
		es.c, _ = v7.New(srv.URL, "ks-logstash-log")
	}
	return es
}

func JsonFromFile(expectedFile string, expectedJsonPtr interface{}) error {
	json, err := ioutil.ReadFile(fmt.Sprintf("./testdata/%s", expectedFile))
	if err != nil {
		return err
	}
	err = jsoniter.Unmarshal(json, expectedJsonPtr)
	if err != nil {
		return err
	}

	return nil
}