package sanitize

import (
	"archive/tar"
	"archive/zip"
	"bytes"
	"compress/gzip"
	"io"
	"strings"
	"testing"
	"time"

	"git.mchus.pro/mchus/logpile/internal/privacy"
)

const leakLog = "" +
	"domain corp.acme.ru\n" +
	"nameserver 10.0.0.1\n" +
	"racdomain=corp.acme.ru\n" +
	"server ntp01.acme.ru\n" +
	"contact ops@corp.acme.ru\n" +
	"outbound 93.184.216.34 established\n" +
	"TimeZone=Europe/Moscow\n" +
	"SELTimeUTCOffset=180\n" +
	"pool at pool.ntp.org keep\n"

func scanClean(t *testing.T, name string, data []byte) {
	t.Helper()
	rep := privacy.Scan([]privacy.File{{Path: name, Content: data}})
	if rep != nil && rep.Summary.Total > 0 {
		var b strings.Builder
		for _, f := range rep.Findings {
			b.WriteString("\n  " + f.Category + " " + f.Match)
		}
		t.Fatalf("%s still has %d findings:%s", name, rep.Summary.Total, b.String())
	}
}

func TestRedactText_LengthPreservedAndClean(t *testing.T) {
	in := []byte(leakLog)
	out, changes := redactText(in, false)

	if len(out) != len(in) {
		t.Fatalf("length changed: %d -> %d", len(in), len(out))
	}
	if len(changes) == 0 {
		t.Fatal("no changes made")
	}
	scanClean(t, "out.log", out)

	// idempotent
	out2, ch2 := redactText(out, false)
	if !bytes.Equal(out, out2) || len(ch2) != 0 {
		t.Fatalf("not idempotent: %d more changes\n%q", len(ch2), out2)
	}

	s := string(out)
	if strings.Contains(s, "acme.ru") || strings.Contains(s, "93.184.216.34") || strings.Contains(s, "Europe/Moscow") {
		t.Fatalf("leak survived:\n%s", s)
	}
	if !strings.Contains(s, "pool.ntp.org") {
		t.Fatal("allowlisted pool.ntp.org was redacted")
	}
	if !strings.Contains(s, "10.0.0.1") {
		t.Fatal("private IP was redacted")
	}
	if !strings.Contains(s, "TimeZone=Etc/Universal") {
		t.Fatalf("timezone not neutralised to a same-length zone:\n%s", s)
	}
	if !strings.Contains(s, "SELTimeUTCOffset=000") {
		t.Fatalf("offset not zeroed:\n%s", s)
	}
}

func TestSanitize_PlainLogNoLeak_ByteIdentical(t *testing.T) {
	in := []byte("just a boring log line\nnothing here\n")
	res, err := Sanitize("x.log", in)
	if err != nil {
		t.Fatal(err)
	}
	if !bytes.Equal(res.Data, in) {
		t.Fatalf("clean input was modified:\n%q", res.Data)
	}
	if res.TotalReplaced != 0 {
		t.Fatalf("changes on clean input: %+v", res.Changes)
	}
}

func buildTar(t *testing.T, members map[string]string) []byte {
	t.Helper()
	var buf bytes.Buffer
	tw := tar.NewWriter(&buf)
	mt := time.Date(2026, 3, 4, 5, 6, 7, 0, time.UTC)
	// deterministic order
	for _, name := range []string{"onekeylog/clean.txt", "onekeylog/configuration/conf/resolv.conf"} {
		body, ok := members[name]
		if !ok {
			continue
		}
		if err := tw.WriteHeader(&tar.Header{
			Name: name, Mode: 0o644, Size: int64(len(body)), ModTime: mt, Typeflag: tar.TypeReg, Format: tar.FormatGNU,
		}); err != nil {
			t.Fatal(err)
		}
		tw.Write([]byte(body))
	}
	tw.Close()
	return buf.Bytes()
}

func tarList(t *testing.T, data []byte) map[string]tar.Header {
	t.Helper()
	m := map[string]tar.Header{}
	tr := tar.NewReader(bytes.NewReader(data))
	for {
		h, err := tr.Next()
		if err == io.EOF {
			break
		}
		if err != nil {
			t.Fatalf("re-read tar: %v", err)
		}
		body, _ := io.ReadAll(tr)
		h.Size = int64(len(body))
		m[h.Name] = *h
	}
	return m
}

func TestSanitize_Tar_PreservesListingAndCleanMember(t *testing.T) {
	members := map[string]string{
		"onekeylog/clean.txt":                      "cpu model Xeon Gold\nmemory 512GB\n",
		"onekeylog/configuration/conf/resolv.conf": leakLog,
	}
	in := buildTar(t, members)
	res, err := Sanitize("dump.tar", in)
	if err != nil {
		t.Fatal(err)
	}

	before, after := tarList(t, in), tarList(t, res.Data)
	if len(before) != len(after) {
		t.Fatalf("member count changed: %d -> %d", len(before), len(after))
	}
	for name, hb := range before {
		ha, ok := after[name]
		if !ok {
			t.Fatalf("member %s vanished", name)
		}
		if hb.Size != ha.Size || hb.Mode != ha.Mode || !hb.ModTime.Equal(ha.ModTime) || hb.Typeflag != ha.Typeflag {
			t.Fatalf("member %s header changed: %+v -> %+v", name, hb, ha)
		}
	}

	// clean member byte-identical
	if memberBytes(t, res.Data, "onekeylog/clean.txt") != members["onekeylog/clean.txt"] {
		t.Fatal("clean member was altered")
	}
	// leak member cleaned
	scanClean(t, "resolv.conf", []byte(memberBytes(t, res.Data, "onekeylog/configuration/conf/resolv.conf")))
	if res.TotalReplaced == 0 {
		t.Fatal("nothing redacted")
	}
}

func memberBytes(t *testing.T, tarData []byte, name string) string {
	t.Helper()
	tr := tar.NewReader(bytes.NewReader(tarData))
	for {
		h, err := tr.Next()
		if err == io.EOF {
			t.Fatalf("member %s not found", name)
		}
		if err != nil {
			t.Fatal(err)
		}
		if h.Name == name {
			b, _ := io.ReadAll(tr)
			return string(b)
		}
	}
}

func TestSanitize_TarGz_PreservesGzipHeaderAndInnerListing(t *testing.T) {
	inner := buildTar(t, map[string]string{
		"onekeylog/clean.txt":                      "board serial ABC123\n",
		"onekeylog/configuration/conf/resolv.conf": leakLog,
	})
	var gz bytes.Buffer
	gw, _ := gzip.NewWriterLevel(&gz, gzip.BestCompression)
	gw.Name = "dump.tar"
	gw.ModTime = time.Date(2026, 1, 2, 3, 4, 5, 0, time.UTC)
	gw.Write(inner)
	gw.Close()

	res, err := Sanitize("dump.tar.gz", gz.Bytes())
	if err != nil {
		t.Fatal(err)
	}

	gr, err := gzip.NewReader(bytes.NewReader(res.Data))
	if err != nil {
		t.Fatal(err)
	}
	if gr.Name != "dump.tar" || !gr.ModTime.Equal(time.Date(2026, 1, 2, 3, 4, 5, 0, time.UTC)) {
		t.Fatalf("gzip header not preserved: name=%q mtime=%v", gr.Name, gr.ModTime)
	}
	out, _ := io.ReadAll(gr)

	before, after := tarList(t, inner), tarList(t, out)
	for name, hb := range before {
		if ha, ok := after[name]; !ok || !hb.ModTime.Equal(ha.ModTime) || hb.Size != ha.Size {
			t.Fatalf("inner member %s changed", name)
		}
	}
	scanClean(t, "inner-resolv", []byte(memberBytes(t, out, "onekeylog/configuration/conf/resolv.conf")))
}

func TestSanitize_Zip_UntouchedEntryIdentical(t *testing.T) {
	var zb bytes.Buffer
	zw := zip.NewWriter(&zb)
	mod := time.Date(2025, 7, 8, 9, 10, 0, 0, time.UTC)
	for _, e := range []struct{ name, body string }{
		{"clean.txt", "hardware inventory only\n"},
		{"host/resolv.conf", leakLog},
	} {
		w, _ := zw.CreateHeader(&zip.FileHeader{Name: e.name, Method: zip.Deflate, Modified: mod})
		w.Write([]byte(e.body))
	}
	zw.Close()

	res, err := Sanitize("bundle.zip", zb.Bytes())
	if err != nil {
		t.Fatal(err)
	}

	zr, err := zip.NewReader(bytes.NewReader(res.Data), int64(len(res.Data)))
	if err != nil {
		t.Fatalf("output zip invalid: %v", err)
	}
	got := map[string]string{}
	for _, f := range zr.File {
		if !f.Modified.Equal(mod) {
			t.Fatalf("%s Modified changed: %v", f.Name, f.Modified)
		}
		rc, _ := f.Open()
		b, _ := io.ReadAll(rc)
		rc.Close()
		got[f.Name] = string(b)
	}
	if got["clean.txt"] != "hardware inventory only\n" {
		t.Fatalf("clean entry altered: %q", got["clean.txt"])
	}
	scanClean(t, "zip-resolv", []byte(got["host/resolv.conf"]))
}

func TestSanitize_BinaryMemberFlagged(t *testing.T) {
	fru := append([]byte{0x01, 0x00, 0x00, 0x00}, []byte("corp.acme.ru\x00padding")...)
	in := func() []byte {
		var buf bytes.Buffer
		tw := tar.NewWriter(&buf)
		tw.WriteHeader(&tar.Header{Name: "onekeylog/FRU.bin", Mode: 0o644, Size: int64(len(fru)), Typeflag: tar.TypeReg})
		tw.Write(fru)
		tw.Close()
		return buf.Bytes()
	}()

	res, err := Sanitize("d.tar", in)
	if err != nil {
		t.Fatal(err)
	}
	if len(res.SkippedBinary) != 1 || !strings.Contains(res.SkippedBinary[0], "FRU.bin") {
		t.Fatalf("binary member not flagged: %+v", res.SkippedBinary)
	}
	if memberBytes(t, res.Data, "onekeylog/FRU.bin") != string(fru) {
		t.Fatal("binary member was modified")
	}
}