package subsystem

import (
	"reflect"
	"testing"
)

func getField(val interface{}, field string) reflect.Value {
	return reflect.ValueOf(val).FieldByName(field)
}

func TestCpuCoreStatUptime(t *testing.T) {
	var corestat *CpuCoreStat

	corestat = new(CpuCoreStat)

	if corestat.Uptime() != 0 {
		t.Errorf("corestat.Uptime() = %v, want %v", corestat.Uptime(), 0)
	}

	corestat.User += 3
	if corestat.Uptime() != 3 {
		t.Errorf("corestat.Uptime() = %v, want %v", corestat.Uptime(), 10)
	}

	corestat.Sys += 5
	if corestat.Uptime() != 8 {
		t.Errorf("corestat.Uptime() = %v, want %v", corestat.Uptime(), 8)
	}

	corestat.Iowait += 7
	if corestat.Uptime() != 15 {
		t.Errorf("corestat.Uptime() = %v, want %v", corestat.Uptime(), 15)
	}

	corestat.Iowait += 11
	if corestat.Uptime() != 26 {
		t.Errorf("corestat.Uptime() = %v, want %v", corestat.Uptime(), 26)
	}

	corestat.Steal += 13
	if corestat.Uptime() != 39 {
		t.Errorf("corestat.Uptime() = %v, want %v", corestat.Uptime(), 39)
	}

	corestat.Hardirq += 17
	if corestat.Uptime() != 56 {
		t.Errorf("corestat.Uptime() = %v, want %v", corestat.Uptime(), 56)
	}

	corestat.Softirq += 19
	if corestat.Uptime() != 75 {
		t.Errorf("corestat.Uptime() = %v, want %v", corestat.Uptime(), 75)
	}

	corestat.Idle += 23
	if corestat.Uptime() != 98 {
		t.Errorf("corestat.Uptime() = %v, want %v", corestat.Uptime(), 98)
	}

	corestat.Nice += 29
	if corestat.Uptime() != 127 {
		t.Errorf("corestat.Uptime() = %v, want %v", corestat.Uptime(), 127)
	}

	corestat.Guest += 31
	if corestat.Uptime() != 127 {
		t.Errorf("corestat.Uptime() = %v, want %v", corestat.Uptime(), 127)
	}

	corestat.GuestNice += 37
	if corestat.Uptime() != 127 {
		t.Errorf("corestat.Uptime() = %v, want %v", corestat.Uptime(), 127)
	}
}

func TestCpuCoreStatClear(t *testing.T) {
	var corestat *CpuCoreStat

	corestat = new(CpuCoreStat)

	corestat.User = 3
	corestat.Sys = 5
	corestat.Iowait = 7
	corestat.Idle = 11
	corestat.Steal = 13
	corestat.Hardirq = 17
	corestat.Softirq = 19
	corestat.Nice = 23
	corestat.Guest = 29
	corestat.GuestNice = 31

	if corestat.User == 0 ||
		corestat.Sys == 0 ||
		corestat.Iowait == 0 ||
		corestat.Idle == 0 ||
		corestat.Steal == 0 ||
		corestat.Hardirq == 0 ||
		corestat.Softirq == 0 ||
		corestat.Nice == 0 ||
		corestat.Guest == 0 ||
		corestat.GuestNice == 0 {
		t.Errorf("corestat = %v, want all fields not to be 0.",
			corestat)
	}

	corestat.Clear()

	if corestat.User != 0 ||
		corestat.Sys != 0 ||
		corestat.Iowait != 0 ||
		corestat.Idle != 0 ||
		corestat.Steal != 0 ||
		corestat.Hardirq != 0 ||
		corestat.Softirq != 0 ||
		corestat.Nice != 0 ||
		corestat.Guest != 0 ||
		corestat.GuestNice != 0 {
		t.Errorf("corestat = %v, want all fields to be 0.",
			corestat)
	}
}

func TestNewCpuStat(t *testing.T) {
	var cpustat *CpuStat
	var num_core int

	num_core = 0
	cpustat = NewCpuStat(num_core)
	if cpustat != nil {
		t.Errorf("NewCore(%d) = %v, want %v",
			num_core, cpustat, nil)
	}

	num_core = 1
	cpustat = NewCpuStat(num_core)
	if cpustat == nil {
		t.Errorf("NewCore(%d) = %v, expect != %v",
			num_core, cpustat, nil)
	}

	for num_core = 1; num_core < 1024; num_core++ {
		cpustat = NewCpuStat(num_core)
		if len(cpustat.CoreStats) != num_core {
			t.Errorf("len(cpustat.CoreStats) = %v, want %v",
				len(cpustat.CoreStats), num_core)
		}
	}
}

func TestCpuStatClear(t *testing.T) {
	num_core := 4
	cpustat := NewCpuStat(num_core)

	cores := []*CpuCoreStat{&cpustat.All}
	for i := 0; i < num_core; i++ {
		cores = append(cores, &cpustat.CoreStats[i])
	}

	for _, corestat := range cores {
		corestat.User = 3
		corestat.Sys = 5
		corestat.Iowait = 7
		corestat.Idle = 11
		corestat.Steal = 13
		corestat.Hardirq = 17
		corestat.Softirq = 19
		corestat.Nice = 23
		corestat.Guest = 29
		corestat.GuestNice = 31
	}

	for _, corestat := range cores {
		if corestat.User == 0 ||
			corestat.Sys == 0 ||
			corestat.Iowait == 0 ||
			corestat.Idle == 0 ||
			corestat.Steal == 0 ||
			corestat.Hardirq == 0 ||
			corestat.Softirq == 0 ||
			corestat.Nice == 0 ||
			corestat.Guest == 0 ||
			corestat.GuestNice == 0 {
			t.Errorf("corestat = %v, want all fields not to be 0.",
				corestat)
		}
	}

	cpustat.Clear()

	for _, corestat := range cores {
		if corestat.User != 0 ||
			corestat.Sys != 0 ||
			corestat.Iowait != 0 ||
			corestat.Idle != 0 ||
			corestat.Steal != 0 ||
			corestat.Hardirq != 0 ||
			corestat.Softirq != 0 ||
			corestat.Nice != 0 ||
			corestat.Guest != 0 ||
			corestat.GuestNice != 0 {
			t.Errorf("corestat = %v, want all fields to be 0.",
				corestat)
		}
	}
}

func TestNewNetStatEntry(t *testing.T) {
	entry := NewNetStatEntry()

	checkField := func(e *NetStatEntry, fieldName string, wanted int64) {
		val := reflect.ValueOf(*e).FieldByName(fieldName).Int()
		if val != wanted {
			t.Errorf(".%s = %v, want %v",
				fieldName, val, wanted)
		}
	}

	checkStrField := func(e *NetStatEntry, fieldName string, wanted string) {
		val := reflect.ValueOf(*e).FieldByName(fieldName).String()
		if val != wanted {
			t.Errorf(".%s = %v, want %v",
				fieldName, val, wanted)
		}
	}

	checkStrField(entry, "Name", "")
	checkField(entry, "RxBytes", 0)
	checkField(entry, "RxPackets", 0)
	checkField(entry, "RxErrors", 0)
	checkField(entry, "RxDrops", 0)
	checkField(entry, "RxFifo", 0)
	checkField(entry, "RxFrame", 0)
	checkField(entry, "RxCompressed", 0)
	checkField(entry, "RxMulticast", 0)
	checkField(entry, "TxBytes", 0)
	checkField(entry, "TxPackets", 0)
	checkField(entry, "TxErrors", 0)
	checkField(entry, "TxDrops", 0)
	checkField(entry, "TxFifo", 0)
	checkField(entry, "TxFrame", 0)
	checkField(entry, "TxCompressed", 0)
	checkField(entry, "TxMulticast", 0)

	entry.Name = "lo"
	entry.RxBytes = 10
	entry.RxPackets = 20

	entry.Clear()

	checkStrField(entry, "Name", "")
	checkField(entry, "RxBytes", 0)
	checkField(entry, "RxPackets", 0)
}

func TestNewNetStat(t *testing.T) {
	netstat := NewNetStat()

	if len(netstat.Entries) != 0 {
		t.Errorf("len(netstat.Entries) = %v, want %v",
			len(netstat.Entries), 0)
	}
}

func TestNewStatRecord(t *testing.T) {
	stat_record := NewStatRecord()

	checkFieldIsNil := func(field string) {
		val := getField(*stat_record, field)
		if !val.IsNil() {
			t.Errorf("stat_record.%s = %v, want %v",
				field, val, nil)
		}
	}

	checkFieldIsNil("Cpu")
	checkFieldIsNil("Proc")
	checkFieldIsNil("Disk")
	checkFieldIsNil("Softirq")
	checkFieldIsNil("Net")
}