package birdfmt

import (
	"net/netip"
	"os"
	"strings"
	"testing"
)

// Ensures generator output matches the standard_layout scenario files (CI bird -p).
func TestStandardLayout_GeneratorMatchesFixtures(t *testing.T) {
	p4 := netip.MustParsePrefix("203.0.113.0/24")

	f4, err := RenderExportFilterIPv4("evobgp_export_v4", []netip.Prefix{p4}, nil)
	if err != nil {
		t.Fatal(err)
	}
	assertFileEquals(t, "testdata/scenarios/standard_layout/bird.d/evobgp_filters_v4.conf", f4)

	f6, err := RenderExportFilterIPv6("evobgp_export_v6", nil, nil)
	if err != nil {
		t.Fatal(err)
	}
	assertFileEquals(t, "testdata/scenarios/standard_layout/bird.d/evobgp_filters_v6.conf", f6)

	staticV4 := RenderStaticIPv4Protocol("evobgp_prefixes_v4", []netip.Prefix{p4})
	assertFileEquals(t, "testdata/scenarios/standard_layout/bird.d/evobgp_prefixes_v4.conf", staticV4)

	staticV6 := RenderStaticIPv6Protocol("evobgp_prefixes_v6", nil)
	assertFileEquals(t, "testdata/scenarios/standard_layout/bird.d/evobgp_prefixes_v6.conf", staticV6)

	tpl, err := RenderBGPTemplates(BGPTemplatesOptions{
		LocalASN:       65001,
		ExportFilterV4: "evobgp_export_v4",
		ExportFilterV6: "evobgp_export_v6",
	})
	if err != nil {
		t.Fatal(err)
	}
	assertFileEquals(t, "testdata/scenarios/standard_layout/bird.d/evobgp_bgp_template.conf", tpl)

	peer, err := RenderProtocolBGPFromTemplate(BGPPeerFromTemplateOptions{
		ProtocolName: "evobgp_peer_ci",
		TemplateName: BGPTemplateNameV4,
		NeighborIP:   "192.0.2.2",
		NeighborASN:  65002,
	})
	if err != nil {
		t.Fatal(err)
	}
	assertFileEquals(t, "testdata/scenarios/standard_layout/bird.d/evobgp_peers.conf", peer)

	main, err := RenderMainBirdConf(MainBirdConfOptions{
		RouterID: "192.0.2.1",
		Includes: StandardIncludeFragments(),
		Preamble: "tags: layout, include, filter, peer\nStandard EvoBGP layout: main skeleton + bird.d fragments (matches StandardIncludeFragments).",
	})
	if err != nil {
		t.Fatal(err)
	}
	// Fixture has two header comment lines; RenderMainBirdConf adds # per line.
	wantMain, err := os.ReadFile("testdata/scenarios/standard_layout/bird.conf")
	if err != nil {
		t.Fatal(err)
	}
	if strings.TrimSpace(main) != strings.TrimSpace(string(wantMain)) {
		t.Fatalf("main bird.conf mismatch\n--- got ---\n%s\n--- want ---\n%s", main, wantMain)
	}
}

func assertFileEquals(t *testing.T, path, content string) {
	t.Helper()
	want, err := os.ReadFile(path)
	if err != nil {
		t.Fatal(err)
	}
	if strings.TrimSpace(content) != strings.TrimSpace(string(want)) {
		t.Fatalf("%s mismatch\n--- got ---\n%s\n--- want ---\n%s", path, content, string(want))
	}
}