website_next: move hash logic to clients

crates/brk_bindgen/src/generators/javascript/client.rs

@@ -688,6 +688,160 @@ const _p = (prefix, acc) => acc ? `${{prefix}}_${{acc}}` : prefix;
 "#
     )
     .unwrap();
+    output.push_str(r##"
+const _MASK_64 = 0xffffffffffffffffn;
+const _RAPIDHASH_SECRETS = /** @type {const} */ ([
+  0x2d358dccaa6c78a5n,
+  0x8bb84b93962eacc9n,
+  0x4b33a62ed433d4a3n,
+  0x4d5a2da51de1aa47n,
+  0xa0761d6478bd642fn,
+  0xe7037ed1a0b428dbn,
+  0x90ed1765281c388cn,
+]);
+const _RAPIDHASH_SEED = _rapidHashSeed(0n);
+
+/** @param {bigint} value */
+function _u64(value) {
+  return value & _MASK_64;
+}
+
+/** @param {bigint} left @param {bigint} right */
+function _rapidMix(left, right) {
+  const result = _u64(left) * _u64(right);
+  return _u64(result) ^ _u64(result >> 64n);
+}
+
+/** @param {bigint} left @param {bigint} right @returns {[bigint, bigint]} */
+function _rapidMum(left, right) {
+  const result = _u64(left) * _u64(right);
+  return [_u64(result), _u64(result >> 64n)];
+}
+
+/** @param {bigint} seed */
+function _rapidHashSeed(seed) {
+  return _u64(seed ^ _rapidMix(seed ^ _RAPIDHASH_SECRETS[2], _RAPIDHASH_SECRETS[1]));
+}
+
+/** @param {Uint8Array} bytes @param {number} offset */
+function _readU32(bytes, offset) {
+  return (
+    BigInt(bytes[offset]) |
+    (BigInt(bytes[offset + 1]) << 8n) |
+    (BigInt(bytes[offset + 2]) << 16n) |
+    (BigInt(bytes[offset + 3]) << 24n)
+  );
+}
+
+/** @param {Uint8Array} bytes @param {number} offset */
+function _readU64(bytes, offset) {
+  return _readU32(bytes, offset) | (_readU32(bytes, offset + 4) << 32n);
+}
+
+/** @param {Uint8Array | ArrayBuffer | ArrayBufferView | number[]} payload */
+function _asUint8Array(payload) {
+  if (payload instanceof Uint8Array) return payload;
+  if (payload instanceof ArrayBuffer) return new Uint8Array(payload);
+  if (ArrayBuffer.isView(payload)) return new Uint8Array(payload.buffer, payload.byteOffset, payload.byteLength);
+  if (Array.isArray(payload)) return new Uint8Array(payload);
+  throw new Error("Expected address payload bytes");
+}
+
+/** @param {Uint8Array | ArrayBuffer | ArrayBufferView | number[]} payload */
+function _rapidHashV3(payload) {
+  const bytes = _asUint8Array(payload);
+  const length = bytes.length;
+  if (length === 0) throw new Error("Expected a non-empty address payload");
+  if (length > 65) throw new Error("Expected at most 65 address payload bytes");
+
+  let seed = _RAPIDHASH_SEED;
+  let a = 0n;
+  let b = 0n;
+  let remainder;
+
+  if (length <= 16) {
+    if (length >= 4) {
+      seed ^= BigInt(length);
+      if (length >= 8) {
+        a ^= _readU64(bytes, 0);
+        b ^= _readU64(bytes, length - 8);
+      } else {
+        a ^= _readU32(bytes, 0);
+        b ^= _readU32(bytes, length - 4);
+      }
+    } else if (length > 0) {
+      a ^= (BigInt(bytes[0]) << 45n) | BigInt(bytes[length - 1]);
+      b ^= BigInt(bytes[length >> 1]);
+    }
+    remainder = BigInt(length);
+  } else {
+    seed = _rapidMix(_readU64(bytes, 0) ^ _RAPIDHASH_SECRETS[2], _readU64(bytes, 8) ^ seed);
+    if (length > 32) {
+      seed = _rapidMix(_readU64(bytes, 16) ^ _RAPIDHASH_SECRETS[2], _readU64(bytes, 24) ^ seed);
+      if (length > 48) {
+        seed = _rapidMix(_readU64(bytes, 32) ^ _RAPIDHASH_SECRETS[1], _readU64(bytes, 40) ^ seed);
+        if (length > 64) {
+          seed = _rapidMix(_readU64(bytes, 48) ^ _RAPIDHASH_SECRETS[1], _readU64(bytes, 56) ^ seed);
+        }
+      }
+    }
+    remainder = BigInt(length);
+    a ^= _readU64(bytes, length - 16) ^ remainder;
+    b ^= _readU64(bytes, length - 8);
+  }
+
+  a ^= _RAPIDHASH_SECRETS[1];
+  b ^= seed;
+  [a, b] = _rapidMum(a, b);
+  return _rapidMix(a ^ 0xaaaaaaaaaaaaaaaan, b ^ _RAPIDHASH_SECRETS[1] ^ remainder);
+}
+
+/** @param {number} nibbles */
+function _validateHashPrefixNibbles(nibbles) {
+  if (!Number.isInteger(nibbles) || nibbles < 1 || nibbles > 16) {
+    throw new Error("Expected hash-prefix length from 1 to 16 hex nibbles");
+  }
+}
+
+/** @param {OutputType} addrType @returns {number[]} */
+function _addressPayloadLengths(addrType) {
+  switch (addrType) {
+    case "p2a": return [2];
+    case "p2pk": return [33, 65];
+    case "p2pkh":
+    case "p2sh":
+    case "v0_p2wpkh": return [20];
+    case "v0_p2wsh":
+    case "v1_p2tr": return [32];
+    default:
+      throw new Error(`Unsupported address type for address payload hash-prefix: ${addrType}`);
+  }
+}
+
+/**
+ * @param {OutputType} addrType
+ * @param {Uint8Array | ArrayBuffer | ArrayBufferView | number[]} payload
+ */
+function _validateAddressPayloadForType(addrType, payload) {
+  const length = _asUint8Array(payload).length;
+  const expected = _addressPayloadLengths(addrType);
+  if (!expected.includes(length)) {
+    throw new Error(`Expected ${addrType} address payload length ${expected.join(" or ")} bytes`);
+  }
+}
+
+/**
+ * Compute the RapidHash v3 hash-prefix used by `/api/address/hash-prefix/{addr_type}/{prefix}`.
+ * @param {Uint8Array | ArrayBuffer | ArrayBufferView | number[]} payload - Raw address payload bytes
+ * @param {number} nibbles - Prefix length from 1 to 16 hex nibbles
+ * @returns {string}
+ */
+function addressPayloadHashPrefix(payload, nibbles) {
+  _validateHashPrefixNibbles(nibbles);
+  return _rapidHashV3(payload).toString(16).padStart(16, "0").slice(0, nibbles);
+}
+
+"##);
 }
 
 /// Generate static constants for the BrkClient class.

crates/brk_bindgen/src/generators/javascript/tree.rs

@@ -111,6 +111,32 @@ pub fn generate_main_client(
     writeln!(output, "    this.series = this._buildTree();").unwrap();
     writeln!(output, "  }}\n").unwrap();
 
+    output.push_str(r##"  /**
+   * Compute the RapidHash v3 hash-prefix for raw address payload bytes.
+   * @param {Uint8Array | ArrayBuffer | ArrayBufferView | number[]} payload
+   * @param {number} nibbles
+   * @returns {string}
+   */
+  static addressPayloadHashPrefix(payload, nibbles) {
+    return addressPayloadHashPrefix(payload, nibbles);
+  }
+
+  /**
+   * Fetch address hash-prefix matches from raw address payload bytes.
+   * @param {OutputType} addrType
+   * @param {Uint8Array | ArrayBuffer | ArrayBufferView | number[]} payload - Raw payload bytes matching addrType length
+   * @param {number} nibbles
+   * @param {{ signal?: AbortSignal, onValue?: (value: AddrHashPrefixMatches) => void, cache?: boolean }} [options]
+   * @returns {Promise<AddrHashPrefixMatches>}
+   */
+  getAddressPayloadHashPrefixMatches(addrType, payload, nibbles, options = {}) {
+    _validateAddressPayloadForType(addrType, payload);
+    const prefix = addressPayloadHashPrefix(payload, nibbles);
+    return this.getAddressHashPrefixMatches(addrType, prefix, options);
+  }
+
+"##);
+
     writeln!(output, "  /**").unwrap();
     writeln!(output, "   * @private").unwrap();
     writeln!(output, "   * @returns {{SeriesTree}}").unwrap();
@@ -161,7 +187,11 @@ pub fn generate_main_client(
 
     writeln!(output, "}}\n").unwrap();
 
-    writeln!(output, "export {{ BrkClient, BrkError }};").unwrap();
+    writeln!(
+        output,
+        "export {{ BrkClient, BrkError, addressPayloadHashPrefix }};"
+    )
+    .unwrap();
 }
 
 #[allow(clippy::too_many_arguments)]

crates/brk_bindgen/src/generators/python/api.rs

@@ -84,6 +84,23 @@ pub fn generate_main_client(output: &mut String, endpoints: &[Endpoint]) {
     .unwrap();
     writeln!(output, "        return _date_to_index(index, d)").unwrap();
     writeln!(output).unwrap();
+
+    output.push_str(r#"    @staticmethod
+    def address_payload_hash_prefix(payload: Union[bytes, bytearray, memoryview], nibbles: int) -> str:
+        """Compute the RapidHash v3 hash-prefix for raw address payload bytes."""
+        return address_payload_hash_prefix(payload, nibbles)
+
+    def get_address_payload_hash_prefix_matches(
+        self,
+        addr_type: OutputType,
+        payload: Union[bytes, bytearray, memoryview],
+        nibbles: int,
+    ) -> AddrHashPrefixMatches:
+        """Fetch address hash-prefix matches from raw payload bytes matching addr_type length."""
+        _validate_address_payload_for_type(addr_type, payload)
+        return self.get_address_hash_prefix_matches(addr_type, address_payload_hash_prefix(payload, nibbles))
+
+"#);
     // Generate API methods
     generate_api_methods(output, endpoints);
 }

crates/brk_bindgen/src/generators/python/client.rs

@@ -147,6 +147,125 @@ def _p(prefix: str, acc: str) -> str:
 "#
     )
     .unwrap();
+    output.push_str(r#"
+_MASK_64 = (1 << 64) - 1
+_RAPIDHASH_SECRETS = (
+    0x2d358dccaa6c78a5,
+    0x8bb84b93962eacc9,
+    0x4b33a62ed433d4a3,
+    0x4d5a2da51de1aa47,
+    0xa0761d6478bd642f,
+    0xe7037ed1a0b428db,
+    0x90ed1765281c388c,
+)
+_RAPIDHASH_SEED = 0
+
+
+def _u64(value: int) -> int:
+    return value & _MASK_64
+
+
+def _rapid_mix(left: int, right: int) -> int:
+    result = _u64(left) * _u64(right)
+    return _u64(result) ^ _u64(result >> 64)
+
+
+def _rapid_mum(left: int, right: int) -> Tuple[int, int]:
+    result = _u64(left) * _u64(right)
+    return _u64(result), _u64(result >> 64)
+
+
+def _rapid_hash_seed(seed: int) -> int:
+    return _u64(seed ^ _rapid_mix(seed ^ _RAPIDHASH_SECRETS[2], _RAPIDHASH_SECRETS[1]))
+
+
+_RAPIDHASH_SEED = _rapid_hash_seed(0)
+
+
+def _read_u32(data: bytes, offset: int) -> int:
+    return int.from_bytes(data[offset:offset + 4], "little")
+
+
+def _read_u64(data: bytes, offset: int) -> int:
+    return int.from_bytes(data[offset:offset + 8], "little")
+
+
+def _rapid_hash_v3(payload: Union[bytes, bytearray, memoryview]) -> int:
+    data = bytes(payload)
+    length = len(data)
+    if length == 0:
+        raise ValueError("Expected a non-empty address payload")
+    if length > 65:
+        raise ValueError("Expected at most 65 address payload bytes")
+
+    seed = _RAPIDHASH_SEED
+    a = 0
+    b = 0
+
+    if length <= 16:
+        if length >= 4:
+            seed ^= length
+            if length >= 8:
+                a ^= _read_u64(data, 0)
+                b ^= _read_u64(data, length - 8)
+            else:
+                a ^= _read_u32(data, 0)
+                b ^= _read_u32(data, length - 4)
+        elif length > 0:
+            a ^= (data[0] << 45) | data[length - 1]
+            b ^= data[length >> 1]
+        remainder = length
+    else:
+        if length > 16:
+            seed = _rapid_mix(_read_u64(data, 0) ^ _RAPIDHASH_SECRETS[2], _read_u64(data, 8) ^ seed)
+            if length > 32:
+                seed = _rapid_mix(_read_u64(data, 16) ^ _RAPIDHASH_SECRETS[2], _read_u64(data, 24) ^ seed)
+                if length > 48:
+                    seed = _rapid_mix(_read_u64(data, 32) ^ _RAPIDHASH_SECRETS[1], _read_u64(data, 40) ^ seed)
+                    if length > 64:
+                        seed = _rapid_mix(_read_u64(data, 48) ^ _RAPIDHASH_SECRETS[1], _read_u64(data, 56) ^ seed)
+        remainder = length
+        a ^= _read_u64(data, length - 16) ^ remainder
+        b ^= _read_u64(data, length - 8)
+
+    a ^= _RAPIDHASH_SECRETS[1]
+    b ^= seed
+    a, b = _rapid_mum(a, b)
+    return _rapid_mix(a ^ 0xaaaaaaaaaaaaaaaa, b ^ _RAPIDHASH_SECRETS[1] ^ remainder)
+
+
+def _validate_hash_prefix_nibbles(nibbles: int) -> None:
+    if isinstance(nibbles, bool) or not isinstance(nibbles, int) or nibbles < 1 or nibbles > 16:
+        raise ValueError("Expected hash-prefix length from 1 to 16 hex nibbles")
+
+
+def _address_payload_lengths(addr_type: OutputType) -> Tuple[int, ...]:
+    if addr_type == "p2a":
+        return (2,)
+    if addr_type == "p2pk":
+        return (33, 65)
+    if addr_type in ("p2pkh", "p2sh", "v0_p2wpkh"):
+        return (20,)
+    if addr_type in ("v0_p2wsh", "v1_p2tr"):
+        return (32,)
+    raise ValueError(f"Unsupported address type for address payload hash-prefix: {addr_type}")
+
+
+def _validate_address_payload_for_type(addr_type: OutputType, payload: Union[bytes, bytearray, memoryview]) -> None:
+    length = len(bytes(payload))
+    expected = _address_payload_lengths(addr_type)
+    if length not in expected:
+        joined = " or ".join(str(value) for value in expected)
+        raise ValueError(f"Expected {addr_type} address payload length {joined} bytes")
+
+
+def address_payload_hash_prefix(payload: Union[bytes, bytearray, memoryview], nibbles: int) -> str:
+    """Compute the RapidHash v3 hash-prefix used by `/api/address/hash-prefix/{addr_type}/{prefix}`."""
+    _validate_hash_prefix_nibbles(nibbles)
+    return f"{_rapid_hash_v3(payload):016x}"[:nibbles]
+
+
+"#);
 }
 
 /// Generate the SeriesData and SeriesEndpoint classes

crates/brk_bindgen/src/generators/rust/api.rs

@@ -76,6 +76,36 @@ impl BrkClient {{
     )
     .unwrap();
 
+    output.push_str(r#"    /// Decode a mainnet Bitcoin address into the BRK address type and raw payload bytes.
+    pub fn decode_address_payload(address: &str) -> Result<AddressPayload> {
+        decode_address_payload(address)
+    }
+
+    /// Compute the RapidHash v3 hash-prefix for raw address payload bytes.
+    pub fn address_payload_hash_prefix(payload: &[u8], nibbles: usize) -> Result<String> {
+        address_payload_hash_prefix(payload, nibbles)
+    }
+
+    /// Decode a mainnet Bitcoin address and compute its hash prefix.
+    pub fn address_hash_prefix(address: &str, nibbles: usize) -> Result<AddressHashPrefix> {
+        address_hash_prefix(address, nibbles)
+    }
+
+    /// Fetch address hash-prefix matches from raw payload bytes matching `addr_type` length.
+    pub fn get_address_payload_hash_prefix_matches(&self, addr_type: OutputType, payload: &[u8], nibbles: usize) -> Result<AddrHashPrefixMatches> {
+        validate_address_payload_for_type(addr_type, payload)?;
+        let prefix = address_payload_hash_prefix(payload, nibbles)?;
+        self.get_address_hash_prefix_matches(addr_type, &prefix)
+    }
+
+    /// Fetch address hash-prefix matches for a mainnet Bitcoin address.
+    pub fn get_address_hash_prefix_matches_for_address(&self, address: &str, nibbles: usize) -> Result<AddrHashPrefixMatches> {
+        let hashed = address_hash_prefix(address, nibbles)?;
+        self.get_address_hash_prefix_matches(hashed.addr_type, &hashed.prefix)
+    }
+
+"#);
+
     generate_api_methods(output, endpoints);
 
     writeln!(output, "}}").unwrap();
@@ -118,6 +148,23 @@ fn generate_get_method(output: &mut String, endpoint: &Endpoint) {
         "get_text"
     };
 
+    if endpoint.path == "/api/address/hash-prefix/{addr_type}/{prefix}" {
+        writeln!(
+            output,
+            "        let addr_type = address_payload_type_path(addr_type)?;"
+        )
+        .unwrap();
+        writeln!(
+            output,
+            "        self.base.{}(&format!(\"{}\"{}))",
+            fetch_method, path, index_arg
+        )
+        .unwrap();
+        writeln!(output, "    }}").unwrap();
+        writeln!(output).unwrap();
+        return;
+    }
+
     if endpoint.query_params.is_empty() {
         writeln!(
             output,

crates/brk_bindgen/src/generators/rust/client.rs

@@ -11,7 +11,8 @@ use crate::{
 pub fn generate_imports(output: &mut String) {
     writeln!(
         output,
-        r#"use std::sync::Arc;
+        r#"use std::str::FromStr;
+use std::sync::Arc;
 use std::ops::{{Bound, RangeBounds}};
 use serde::de::DeserializeOwned;
 pub use brk_cohort::*;
@@ -43,6 +44,97 @@ impl std::error::Error for BrkError {{}}
 /// Result type for BRK client operations.
 pub type Result<T> = std::result::Result<T, BrkError>;
 
+/// BRK address type and raw payload bytes used by the hash-prefix index.
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub struct AddressPayload {{
+    pub addr_type: OutputType,
+    pub payload: Vec<u8>,
+}}
+
+/// BRK address type and leading hex nibbles of the address-payload hash.
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub struct AddressHashPrefix {{
+    pub addr_type: OutputType,
+    pub prefix: String,
+}}
+
+/// Compute the RapidHash v3 hash-prefix used by `/api/address/hash-prefix/{{addr_type}}/{{prefix}}`.
+pub fn address_payload_hash_prefix(payload: &[u8], nibbles: usize) -> Result<String> {{
+    if payload.is_empty() {{
+        return Err(BrkError {{ message: "Expected a non-empty address payload".to_string() }});
+    }}
+    if payload.len() > 65 {{
+        return Err(BrkError {{ message: "Expected at most 65 address payload bytes".to_string() }});
+    }}
+    if !(1..=16).contains(&nibbles) {{
+        return Err(BrkError {{ message: "Expected hash-prefix length from 1 to 16 hex nibbles".to_string() }});
+    }}
+    Ok(format!("{{:016x}}", rapidhash::v3::rapidhash_v3(payload))[..nibbles].to_string())
+}}
+
+fn validate_address_payload_for_type(addr_type: OutputType, payload: &[u8]) -> Result<()> {{
+    let expected: &[usize] = match addr_type {{
+        OutputType::P2A => &[2],
+        OutputType::P2PK33 => &[33],
+        OutputType::P2PK65 => &[65],
+        OutputType::P2PKH | OutputType::P2SH | OutputType::P2WPKH => &[20],
+        OutputType::P2WSH | OutputType::P2TR => &[32],
+        OutputType::P2MS | OutputType::OpReturn | OutputType::Empty | OutputType::Unknown => {{
+            return Err(BrkError {{ message: format!("Unsupported address type for address payload hash-prefix: {{addr_type:?}}") }});
+        }},
+    }};
+    let addr_type = address_payload_type_path(addr_type)?;
+
+    if !expected.contains(&payload.len()) {{
+        let joined = expected
+            .iter()
+            .map(ToString::to_string)
+            .collect::<Vec<_>>()
+            .join(" or ");
+        return Err(BrkError {{ message: format!("Expected {{addr_type}} address payload length {{joined}} bytes") }});
+    }}
+
+    Ok(())
+}}
+
+fn address_payload_type_path(addr_type: OutputType) -> Result<&'static str> {{
+    match addr_type {{
+        OutputType::P2A => Ok("p2a"),
+        OutputType::P2PK33 | OutputType::P2PK65 => Ok("p2pk"),
+        OutputType::P2PKH => Ok("p2pkh"),
+        OutputType::P2SH => Ok("p2sh"),
+        OutputType::P2WPKH => Ok("v0_p2wpkh"),
+        OutputType::P2WSH => Ok("v0_p2wsh"),
+        OutputType::P2TR => Ok("v1_p2tr"),
+        OutputType::P2MS | OutputType::OpReturn | OutputType::Empty | OutputType::Unknown => {{
+            Err(BrkError {{ message: format!("Unsupported address type for address payload hash-prefix: {{addr_type:?}}") }})
+        }},
+    }}
+}}
+
+/// Decode a mainnet Bitcoin address into the BRK address type and raw payload bytes.
+pub fn decode_address_payload(address: &str) -> Result<AddressPayload> {{
+    if address.is_empty() {{
+        return Err(BrkError {{ message: "Expected an address string".to_string() }});
+    }}
+    let addr_bytes = AddrBytes::from_str(address).map_err(|e| BrkError {{ message: e.to_string() }})?;
+    let addr_type = OutputType::from(&addr_bytes);
+
+    Ok(AddressPayload {{
+        addr_type,
+        payload: addr_bytes.as_slice().to_vec(),
+    }})
+}}
+
+/// Decode a mainnet Bitcoin address and compute its hash prefix.
+pub fn address_hash_prefix(address: &str, nibbles: usize) -> Result<AddressHashPrefix> {{
+    let decoded = decode_address_payload(address)?;
+    Ok(AddressHashPrefix {{
+        addr_type: decoded.addr_type,
+        prefix: address_payload_hash_prefix(&decoded.payload, nibbles)?,
+    }})
+}}
+
 /// Options for configuring the BRK client.
 #[derive(Debug, Clone)]
 pub struct BrkClientOptions {{