package kyoketsu

import (
	"encoding/json"
	"fmt"
	"log"
	"net"
	"os"
	"testing"
)

type IpAddresses struct {
	Addrs []string `json:"addresses"`
}

func LoadTestAddresses(loc string) map[string]struct{} {
	b, err := os.ReadFile(loc)
	if err != nil {
		log.Fatal("Test setup failed.\n", err)
	}
	var addr IpAddresses
	addrmap := map[string]struct{}{}
	err = json.Unmarshal(b, &addr)
	if err != nil {
		log.Fatal("test setup failed.\n", err)
	}
	for i := range addr.Addrs {
		addrmap[addr.Addrs[i]] = struct{}{}
	}
	return addrmap

}

// Testing the addres recursion function to return all IPs in the target address subnet
// All test cases use a select sort to assert that all addresses in the test data are in the return
func TestAddressRecurse(t *testing.T) {
	type TestCase struct {
		Name       string
		TestData   string
		InputAddr  string
		InputMask  int
		ShouldFail bool
	}

	tc := []TestCase{
		TestCase{
			Name:      "Passing testcase with valid IP address, returns all addresses.",
			TestData:  "../test/local_ips.json",
			InputAddr: "192.168.50.50",
			InputMask: 24,
		},
		TestCase{
			Name:      "Passing testcase with valid IP address that belongs to a /16 subnet",
			TestData:  "../test/slash16_ips.json",
			InputAddr: "10.252.1.1",
			InputMask: 16,
		},
	}
	for i := range tc {
		addr, network, err := net.ParseCIDR(fmt.Sprintf("%s/%v", tc[i].InputAddr, tc[i].InputMask))
		if err != nil {
			t.Errorf("Test case: '%s' failed! Reason: %s", tc[i].Name, err)
		}
		got := &IpSubnetMapper{}
		got.Mask = tc[i].InputMask
		got.NetworkAddr = addr.Mask(network.Mask)
		got.Current = addr.Mask(network.Mask)
		addressRecurse(got, 65535)
		want := LoadTestAddresses(tc[i].TestData)
		for x := range got.Ipv4s {
			gotip := got.Ipv4s[x]
			_, ok := want[gotip.String()]
			if !ok {
				t.Errorf("Test '%s' failed! Address: %s was not found in the test data: %s\n", tc[i].Name, gotip.String(), tc[i].TestData)
			}

		}
		log.Printf("Nice! Test: '%s' passed!\n", tc[i].Name)
	}

}

// Testing the function to retrieve the next network address
func TestGetNextAddr(t *testing.T) {
	type TestCase struct {
		Name       string
		Input      string
		Wants      string
		ShouldFail bool
	}

	tc := []TestCase{
		TestCase{
			Name:       "Passing test case, function returns the next address",
			Input:      "10.252.1.1",
			Wants:      "10.252.1.2",
			ShouldFail: false,
		},
		TestCase{
			Name:       "Failing test case, function returns the wrong address",
			Input:      "10.252.1.1",
			Wants:      "10.252.1.4",
			ShouldFail: true,
		},
	}
	for i := range tc {
		got := getNextAddr(tc[i].Input)
		if got != tc[i].Wants {
			if !tc[i].ShouldFail {
				t.Errorf("Test: '%s' failed! Return: %s\nTest expected: %s\nTest Should fail: %v\n", tc[i].Name, got, tc[i].Wants, tc[i].ShouldFail)
			}

		}
	}

}

func TestGetNetwork(t *testing.T) {
	type TestCase struct {
		Name       string
		InputAddr  string
		InputMask  int
		Expects    string
		ShouldFail bool
	}
	tc := []TestCase{
		TestCase{
			Name:       "Passing test, function returns the correct network given the CIDR mask",
			InputAddr:  "192.168.50.35",
			InputMask:  24,
			Expects:    "192.168.50.0",
			ShouldFail: false,
		},
		TestCase{
			Name:       "Passing test, function returns the correct network given the CIDR mask (Larger network, /16 CIDR)",
			InputAddr:  "10.252.47.200",
			InputMask:  16,
			Expects:    "10.252.0.0",
			ShouldFail: false,
		},
	}
	for i := range tc {
		got := getNetwork(tc[i].InputAddr, tc[i].InputMask)
		if got != tc[i].Expects {
			if !tc[i].ShouldFail {
				t.Errorf("Test: '%s' failed! Returned: %s\nExpected: %s\nShould fail: %v", tc[i].Name, got, tc[i].Expects, tc[i].ShouldFail)
			}

		}

	}

}