| 1 | package tinyclient |
| 2 | |
| 3 | import ( |
| 4 | "encoding/binary" |
| 5 | "encoding/hex" |
| 6 | "net/url" |
| 7 | "regexp" |
| 8 | "strings" |
| 9 | ) |
| 10 | |
| 11 | func identityNpub(identity string) string { |
| 12 | decoded, err := hex.DecodeString(identity) |
| 13 | if err != nil || len(decoded) != 32 { |
| 14 | return identity |
| 15 | } |
| 16 | return bech32("npub" , decoded) |
| 17 | } |
| 18 | |
| 19 | const bech32Charset = "qpzry9x8gf2tvdw0s3jn54khce6mua7l" |
| 20 | |
| 21 | // bech32 encodes data with the given human readable part. |
| 22 | func bech32(hrp string, data []byte) string { |
| 23 | fiveBits := convertBits(data) |
| 24 | expanded := make([]byte, 0, len(hrp)*2+1) |
| 25 | for _, c := range hrp { |
| 26 | expanded = append(expanded, byte(c)>>5) |
| 27 | } |
| 28 | expanded = append(expanded, 0) |
| 29 | for _, c := range hrp { |
| 30 | expanded = append(expanded, byte(c)&31) |
| 31 | } |
| 32 | values := append(append(append([]byte{}, expanded...), fiveBits...), 0, 0, 0, 0, 0, 0) |
| 33 | polymod := bech32Polymod(values) ^ 1 |
| 34 | checksum := make([]byte, 6) |
| 35 | for i := range checksum { |
| 36 | checksum[i] = byte(polymod >> uint(5*(5-i)) & 31) |
| 37 | } |
| 38 | var out strings.Builder |
| 39 | out.WriteString(hrp + "1" ) |
| 40 | for _, value := range append(fiveBits, checksum...) { |
| 41 | out.WriteByte(bech32Charset[value]) |
| 42 | } |
| 43 | return out.String() |
| 44 | } |
| 45 | |
| 46 | func convertBits(data []byte) []byte { |
| 47 | result := make([]byte, 0, 52) |
| 48 | accumulator, bits := 0, 0 |
| 49 | for _, value := range data { |
| 50 | accumulator = (accumulator << 8) | int(value) |
| 51 | bits += 8 |
| 52 | for bits >= 5 { |
| 53 | bits -= 5 |
| 54 | result = append(result, byte(accumulator>>bits&31)) |
| 55 | } |
| 56 | } |
| 57 | if bits > 0 { |
| 58 | result = append(result, byte(accumulator<<(5-bits)&31)) |
| 59 | } |
| 60 | return result |
| 61 | } |
| 62 | |
| 63 | func bech32Polymod(values []byte) uint64 { |
| 64 | generators := [...]uint64{0x3b6a57b2, 0x26508e6d, 0x1ea119fa, 0x3d4233dd, 0x2a1462b3} |
| 65 | checksum := uint64(1) |
| 66 | for _, value := range values { |
| 67 | top := checksum >> 25 |
| 68 | checksum = (checksum&0x1ffffff)<<5 ^ uint64(value) |
| 69 | for i, generator := range generators { |
| 70 | if top>>uint(i)&1 != 0 { |
| 71 | checksum ^= generator |
| 72 | } |
| 73 | } |
| 74 | } |
| 75 | return checksum |
| 76 | } |
| 77 | |
| 78 | func tlv(kind byte, value []byte) []byte { |
| 79 | return append([]byte{kind, byte(len(value))}, value...) |
| 80 | } |
| 81 | |
| 82 | // nprofile encodes a NIP-19 profile pointer with one relay hint. |
| 83 | func nprofile(pubkeyHex, relay string) string { |
| 84 | pubkey, err := hex.DecodeString(pubkeyHex) |
| 85 | if err != nil || len(pubkey) != 32 { |
| 86 | return "" |
| 87 | } |
| 88 | data := tlv(0, pubkey) |
| 89 | if relay != "" { |
| 90 | data = append(data, tlv(1, []byte(relay))...) |
| 91 | } |
| 92 | return bech32("nprofile" , data) |
| 93 | } |
| 94 | |
| 95 | // naddr encodes a NIP-19 address pointer for a replaceable event. |
| 96 | func naddr(kind uint32, pubkeyHex, identifier, relay string) string { |
| 97 | pubkey, err := hex.DecodeString(pubkeyHex) |
| 98 | if err != nil || len(pubkey) != 32 { |
| 99 | return "" |
| 100 | } |
| 101 | data := tlv(0, []byte(identifier)) |
| 102 | if relay != "" { |
| 103 | data = append(data, tlv(1, []byte(relay))...) |
| 104 | } |
| 105 | data = append(data, tlv(2, pubkey)...) |
| 106 | kindBytes := make([]byte, 4) |
| 107 | binary.BigEndian.PutUint32(kindBytes, kind) |
| 108 | data = append(data, tlv(3, kindBytes)...) |
| 109 | return bech32("naddr" , data) |
| 110 | } |
| 111 | |
| 112 | var placeholder = regexp.MustCompile(`\{([a-z]+):([a-z]+)(?:\|(enc))?\}` ) |
| 113 | |
| 114 | // connectionValues resolves the placeholders connection templates use: |
| 115 | // relay:url, relay:web, relay:host, relay:domain, relay:naddr, owner:npub, |
| 116 | // owner:nprofile, user:npub and user:nprofile. The relay's group address is |
| 117 | // its NIP-29 top-level group, published under the relay identity. |
| 118 | func connectionValues(data PageData) map[string]string { |
| 119 | values := map[string]string{} |
| 120 | web := strings.TrimRight(data.URL, "/" ) |
| 121 | values["relay:web" ] = web |
| 122 | values["relay:url" ] = wsURL(web) |
| 123 | if parsed, err := url.Parse(web); err == nil { |
| 124 | values["relay:host" ] = parsed.Host |
| 125 | values["relay:domain" ] = parsed.Hostname() |
| 126 | } |
| 127 | if data.Identity != "" { |
| 128 | values["relay:naddr" ] = naddr(39000, data.Identity, "_" , values["relay:url" ]) |
| 129 | } |
| 130 | if data.Policy.Owner != "" { |
| 131 | values["owner:npub" ] = identityNpub(data.Policy.Owner) |
| 132 | values["owner:nprofile" ] = nprofile(data.Policy.Owner, values["relay:url" ]) |
| 133 | } |
| 134 | if data.Actor != "" { |
| 135 | values["user:npub" ] = identityNpub(data.Actor) |
| 136 | values["user:nprofile" ] = nprofile(data.Actor, values["relay:url" ]) |
| 137 | } |
| 138 | return values |
| 139 | } |
| 140 | |
| 141 | // fillPlaceholders substitutes known values, leaving input placeholders for |
| 142 | // the page script. It reports false when a needed value is missing, such as |
| 143 | // a user value for a guest, so the link can be left out. |
| 144 | func fillPlaceholders(text string, values map[string]string) (string, bool) { |
| 145 | complete := true |
| 146 | out := placeholder.ReplaceAllStringFunc(text, func(match string) string { |
| 147 | parts := placeholder.FindStringSubmatch(match) |
| 148 | if parts[1] == "input" { |
| 149 | return match |
| 150 | } |
| 151 | value, ok := values[parts[1]+":" +parts[2]] |
| 152 | if !ok || value == "" { |
| 153 | complete = false |
| 154 | return "" |
| 155 | } |
| 156 | if parts[3] == "enc" { |
| 157 | return url.QueryEscape(value) |
| 158 | } |
| 159 | return value |
| 160 | }) |
| 161 | return out, complete |
| 162 | } |
| 163 | |
| 164 | // expandConnections turns the daemon's connection rows into ready-to-render |
| 165 | // maps with placeholders resolved. Links that need a signed-in user are |
| 166 | // dropped for guests; the card keeps a note that signing in reveals them. |
| 167 | func expandConnections(rows []any, data PageData) []any { |
| 168 | values := connectionValues(data) |
| 169 | out := make([]any, 0, len(rows)) |
| 170 | for _, row := range rows { |
| 171 | item := valueMap(row) |
| 172 | card := map[string]any{"name" : plainString(item["template" ]), "title" : plainString(item["title" ]), "about" : plainString(item["about" ]), "app" : plainString(item["app" ]), "where" : plainString(item["where" ]), "visibility" : plainString(item["visibility" ]), "inputs" : item["inputs" ]} |
| 173 | if card["title" ] == "" { |
| 174 | card["title" ] = card["name" ] |
| 175 | } |
| 176 | if qr, ok := fillPlaceholders(plainString(item["qr" ]), values); ok && qr != "" { |
| 177 | card["qr" ] = qr |
| 178 | } |
| 179 | links := []any{} |
| 180 | hidden := 0 |
| 181 | for _, link := range browseRows(item["links" ]) { |
| 182 | l := valueMap(link) |
| 183 | field := func(name string) string { |
| 184 | if value := plainString(l[name]); value != "" { |
| 185 | return value |
| 186 | } |
| 187 | return plainString(l[strings.ToUpper(name[:1])+name[1:]]) |
| 188 | } |
| 189 | href, okHref := fillPlaceholders(field("href" ), values) |
| 190 | copyText, okCopy := fillPlaceholders(field("copy" ), values) |
| 191 | if !okHref || !okCopy { |
| 192 | hidden++ |
| 193 | continue |
| 194 | } |
| 195 | links = append(links, map[string]any{"label" : field("label" ), "href" : href, "copy" : copyText}) |
| 196 | } |
| 197 | card["links" ], card["hidden" ] = links, hidden |
| 198 | out = append(out, card) |
| 199 | } |
| 200 | return out |
| 201 | } |
