// Copyright 2015 The Prometheus Authors
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package collector

import (
	"regexp"
	"testing"

	"github.com/coreos/go-systemd/dbus"
	"github.com/prometheus/client_golang/prometheus"
)

// Creates mock UnitLists
func getUnitListFixtures() [][]dbus.UnitStatus {
	fixture1 := []dbus.UnitStatus{
		{
			Name:        "foo",
			Description: "foo desc",
			LoadState:   "loaded",
			ActiveState: "active",
			SubState:    "running",
			Followed:    "",
			Path:        "/org/freedesktop/systemd1/unit/foo",
			JobId:       0,
			JobType:     "",
			JobPath:     "/",
		},
		{
			Name:        "bar",
			Description: "bar desc",
			LoadState:   "not-found",
			ActiveState: "inactive",
			SubState:    "dead",
			Followed:    "",
			Path:        "/org/freedesktop/systemd1/unit/bar",
			JobId:       0,
			JobType:     "",
			JobPath:     "/",
		},
		{
			Name:        "foobar",
			Description: "bar desc",
			LoadState:   "not-found",
			ActiveState: "inactive",
			SubState:    "dead",
			Followed:    "",
			Path:        "/org/freedesktop/systemd1/unit/bar",
			JobId:       0,
			JobType:     "",
			JobPath:     "/",
		},
		{
			Name:        "baz",
			Description: "bar desc",
			LoadState:   "not-found",
			ActiveState: "inactive",
			SubState:    "dead",
			Followed:    "",
			Path:        "/org/freedesktop/systemd1/unit/bar",
			JobId:       0,
			JobType:     "",
			JobPath:     "/",
		},
	}

	fixture2 := []dbus.UnitStatus{}

	return [][]dbus.UnitStatus{fixture1, fixture2}
}

func TestSystemdCollectorDoesntCrash(t *testing.T) {
	c, err := NewSystemdCollector()
	if err != nil {
		t.Fatal(err)
	}
	sink := make(chan prometheus.Metric)
	go func() {
		for {
			<-sink
		}
	}()

	fixtures := getUnitListFixtures()
	collector := (c).(*systemdCollector)
	for _, units := range fixtures {
		collector.collectUnitStatusMetrics(sink, units)
	}
}

func TestSystemdIgnoreFilter(t *testing.T) {
	fixtures := getUnitListFixtures()
	whitelistPattern := regexp.MustCompile("foo")
	blacklistPattern := regexp.MustCompile("bar")
	filtered := filterUnits(fixtures[0], whitelistPattern, blacklistPattern)
	for _, unit := range filtered {
		if blacklistPattern.MatchString(unit.Name) || !whitelistPattern.MatchString(unit.Name) {
			t.Error(unit.Name, "should not be in the filtered list")
		}
	}
}
func TestSystemdIgnoreFilterDefaultKeepsAll(t *testing.T) {
	c, err := NewSystemdCollector()
	if err != nil {
		t.Fatal(err)
	}
	fixtures := getUnitListFixtures()
	collector := c.(*systemdCollector)
	filtered := filterUnits(fixtures[0], collector.unitWhitelistPattern, collector.unitBlacklistPattern)
	if len(filtered) != len(fixtures[0]) {
		t.Error("Default filters removed units")
	}
}

func TestSystemdSummary(t *testing.T) {
	fixtures := getUnitListFixtures()
	summary := summarizeUnits(fixtures[0])

	for _, state := range unitStatesName {
		if state == "inactive" {
			testSummaryHelper(t, state, summary[state], 3.0)
		} else if state == "active" {
			testSummaryHelper(t, state, summary[state], 1.0)
		} else {
			testSummaryHelper(t, state, summary[state], 0.0)
		}
	}
}

func testSummaryHelper(t *testing.T, state string, actual float64, expected float64) {
	if actual != expected {
		t.Errorf("Summary mode didn't count %s jobs correctly. Actual: %f, expected: %f", state, actual, expected)
	}
}