package app

import (
	"context"
	"os"
	"strings"
	"testing"
	"time"
)

func TestBuildTransportPolicyCIDRSetElements(t *testing.T) {
	in := []TransportPolicyCompileInterface{
		{
			IfaceID: "edge-a",
			Rules: []TransportPolicyCompileRule{
				{SelectorType: "cidr", SelectorValue: "10.1.0.0/24", NftSet: "agvpn_pi_edge_a_cidr"},
				{SelectorType: "cidr", SelectorValue: "10.1.0.5", NftSet: "agvpn_pi_edge_a_cidr"},
				{SelectorType: "domain", SelectorValue: "example.com", NftSet: "agvpn_pi_edge_a_domain"},
			},
		},
	}
	got := buildTransportPolicyCIDRSetElements(in)
	ips := got["agvpn_pi_edge_a_cidr"]
	if len(ips) != 2 {
		t.Fatalf("unexpected cidr elements: %#v", got)
	}
}

func TestApplyTransportPolicyKernelNftSets(t *testing.T) {
	prevRun := transportPolicyKernelRunCommand
	prevUpdate := transportPolicyKernelUpdateSet
	defer func() {
		transportPolicyKernelRunCommand = prevRun
		transportPolicyKernelUpdateSet = prevUpdate
	}()

	var cmds []string
	transportPolicyKernelRunCommand = func(timeout time.Duration, name string, args ...string) (string, string, int, error) {
		cmds = append(cmds, name+" "+strings.Join(args, " "))
		return "", "", 0, nil
	}
	updates := map[string][]string{}
	transportPolicyKernelUpdateSet = func(_ context.Context, setName string, ips []string) error {
		updates[setName] = append([]string(nil), ips...)
		return nil
	}

	current := transportPolicyRuntimeState{
		Interfaces: []TransportPolicyCompileInterface{
			{
				IfaceID: "edge-old",
				Sets: []TransportPolicyCompileSet{
					{SelectorType: "cidr", Name: "agvpn_pi_edge_old_cidr"},
				},
			},
		},
	}
	staged := transportPolicyRuntimeState{
		Interfaces: []TransportPolicyCompileInterface{
			{
				IfaceID: "edge-a",
				Rules: []TransportPolicyCompileRule{
					{SelectorType: "cidr", SelectorValue: "10.1.0.0/24", NftSet: "agvpn_pi_edge_a_cidr"},
				},
			},
		},
	}
	if err := applyTransportPolicyKernelNftSets(current, staged); err != nil {
		t.Fatalf("unexpected error: %v", err)
	}
	if len(updates["agvpn_pi_edge_a_cidr"]) != 1 {
		t.Fatalf("expected update for desired set, got: %#v", updates)
	}
	hasDeleteStale := false
	for _, cmd := range cmds {
		if strings.Contains(cmd, "delete set inet agvpn agvpn_pi_edge_old_cidr") {
			hasDeleteStale = true
			break
		}
	}
	if !hasDeleteStale {
		t.Fatalf("expected stale set cleanup command, got: %#v", cmds)
	}
}

func TestApplyTransportPolicyKernelStageDisabled(t *testing.T) {
	prevRun := transportPolicyKernelRunCommand
	defer func() { transportPolicyKernelRunCommand = prevRun }()
	called := false
	transportPolicyKernelRunCommand = func(timeout time.Duration, name string, args ...string) (string, string, int, error) {
		called = true
		return "", "", 0, nil
	}

	prev := os.Getenv(transportPolicyKernelEnvEnable)
	_ = os.Setenv(transportPolicyKernelEnvEnable, "0")
	defer func() { _ = os.Setenv(transportPolicyKernelEnvEnable, prev) }()

	if err := applyTransportPolicyKernelStage(transportPolicyRuntimeState{}, transportPolicyRuntimeState{}); err != nil {
		t.Fatalf("unexpected error: %v", err)
	}
	if called {
		t.Fatalf("kernel stage must be skipped when disabled")
	}
}