package go_ntp_test

import (
	"fmt"
	"regexp"
	"testing"

	ntp "git.sa-roci.de/oss/go_ntp"
	server "github.com/coreos/mantle/network/ntp"
)

var (
	testCases = []struct {
		ntpServers    []string
		expectedError string
		createLocal   bool
	}{
		{
			ntpServers:    []string{},
			expectedError: `no time servers defined`,
		},
		{
			ntpServers: []string{
				"127.0.0.1",
			},
			expectedError: `read udp 127\.0\.0\.1:\d+->127\.0\.0\.1:123:`,
		},
		{
			ntpServers: ntp.GetDefaultServers(),
		},
		{
			ntpServers: []string{
				"127.0.0.1:1880",
			},
			createLocal: true,
		},
	}
)

func TestGetCurrentTime(t *testing.T) {
	for i, testCase := range testCases {
		var srv *server.Server
		if testCase.createLocal {
			var err error
			if srv, err = server.NewServer("127.0.0.1:1880"); err == nil {
				go srv.Serve()
			} else {
				t.Errorf("TestGetCurrentTime: test case %d: could not create local NTP server: %s", i+1, err)
				continue
			}
		}

		if synced, err := ntp.GetCurrentTime(testCase.ntpServers...); err == nil {
			if testCase.expectedError == "" {
				fmt.Printf("TestGetCurrentTime: test case %d: retrieved NTP time: %s\n", i+1, synced)
			} else {
				t.Errorf("TestGetCurrentTime: test case %d: expected error (%s) did not occur", i+1, testCase.expectedError)
			}
		} else {
			if testCase.expectedError == "" {
				t.Errorf("TestGetCurrentTime: test case %d: got unexpected error (%s)", i+1, err.Error())
			} else {
				tester := regexp.MustCompile(testCase.expectedError)
				if !tester.MatchString(err.Error()) {
					t.Errorf("TestGetCurrentTime: test case %d: expected error to match '%s' but got '%s'", i+1, testCase.expectedError, err.Error())
				}
			}
		}

		if srv != nil {
			srv.Close()
		}
	}
}

func TestGetLocalOffset(t *testing.T) {
	for i, testCase := range testCases {
		var srv *server.Server
		if testCase.createLocal {
			var err error
			if srv, err = server.NewServer("127.0.0.1:1880"); err == nil {
				go srv.Serve()
			} else {
				t.Errorf("TestGetLocalOffset: test case %d: could not create local NTP server: %s", i+1, err)
				continue
			}
		}

		if offset, err := ntp.GetLocalOffset(testCase.ntpServers...); err == nil {
			if testCase.expectedError == "" {
				fmt.Printf("TestGetCurrentTime: test case %d: retrieved NTP time offset: %s\n", i+1, offset)
			} else {
				t.Errorf("TestGetCurrentTime: test case %d: expected error (%s) did not occur", i+1, testCase.expectedError)
			}
		} else {
			if testCase.expectedError == "" {
				t.Errorf("TestGetCurrentTime: test case %d: got unexpected error (%s)", i+1, err.Error())
			} else {
				tester := regexp.MustCompile(testCase.expectedError)
				if !tester.MatchString(err.Error()) {
					t.Errorf("TestGetCurrentTime: test case %d: expected error to match '%s' but got '%s'", i+1, testCase.expectedError, err.Error())
				}
			}
		}

		if srv != nil {
			srv.Close()
		}
	}
}