package alpine

import (
	"archive/tar"
	"bytes"
	"compress/gzip"
	"fmt"
	"testing"
)

func apkindexTarGz(entries [][2]string) []byte {
	var buf bytes.Buffer
	gz := gzip.NewWriter(&buf)
	tw := tar.NewWriter(gz)
	sig := []byte("not a real signature")
	tw.WriteHeader(&tar.Header{Name: ".SIGN.RSA.alpine-devel@lists.alpinelinux.org-6165ee59.rsa.pub", Mode: 0o644, Size: int64(len(sig))})
	tw.Write(sig)
	tw.Flush() // no Close: apk's signature segment has no trailer
	gz.Close()

	var idx bytes.Buffer
	for _, e := range entries {
		fmt.Fprintf(&idx, "C:Q1x=\nP:%s\nV:1.0-r0\nA:x86_64\nU:https://example.org/\n", e[0])
		if e[1] != "" {
			fmt.Fprintf(&idx, "o:%s\n", e[1])
		}
		idx.WriteString("t:1\n\n")
	}
	gz = gzip.NewWriter(&buf)
	tw = tar.NewWriter(gz)
	desc := []byte("alpine-edge-main")
	tw.WriteHeader(&tar.Header{Name: "DESCRIPTION", Mode: 0o644, Size: int64(len(desc))})
	tw.Write(desc)
	tw.WriteHeader(&tar.Header{Name: "APKINDEX", Mode: 0o644, Size: int64(idx.Len())})
	tw.Write(idx.Bytes())
	tw.Close()
	gz.Close()
	return buf.Bytes()
}

func TestParseAPKINDEX(t *testing.T) {
	entries, err := ParseAPKINDEX(apkindexTarGz([][2]string{{"curl", "curl"}, {"libcurl", "curl"}}))
	if err != nil {
		t.Fatal(err)
	}
	if len(entries) != 2 || entries[1].Name != "libcurl" || entries[1].Origin != "curl" || entries[1].Version != "1.0-r0" || entries[1].URL != "https://example.org/" {
		t.Errorf("entries = %+v", entries)
	}
	if _, err := ParseAPKINDEX([]byte("not gzip")); err == nil {
		t.Error("garbage should fail")
	}
}