Add child key pair generation api

CHANGELOG.md

@@ -5,6 +5,29 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
 ## [Unreleased]
+- APIs Added [#154]
+  - `generate_mnemonic()`, returns string mnemonic
+  - `interface DescriptorSecretKey`
+    - `new(Network, string_mnenoinc, password)`, contructs DescriptorSecretKey
+    - `derive(DerivationPath)`, derives and returns child DescriptorSecretKey
+    - `extend(DerivationPath)`, extends and returns DescriptorSecretKey
+    - `as_public()`, returns DescriptorSecretKey as DescriptorPublicKey
+    - `as_string()`, returns DescriptorSecretKey as String
+  - `interface DescriptorPublicKey`
+    - `derive(DerivationPath)` derives and returns child DescriptorPublicKey
+    - `extend(DerivationPath)` extends and returns DescriptorPublicKey
+    - `as_string()` returns DescriptorPublicKey as String
+- Interfaces Added [#154]
+  - `DescriptorSecretKey`
+  - `DescriptorPublicKey`
+  - `DerivationPath`
+- Dictionary Removed [#154]
+  - `ExtendedKeyInfo {mnenonic, xprv, fingerprint}` 
+- APIs Removed [#154]
+  - `generate_extended_key`, returned ExtendedKeyInfo
+  - `restore_extended_key`, returned ExtendedKeyInfo
+
+[#154]: https://github.com/bitcoindevkit/bdk-ffi/pull/154
 
 ## [v0.8.0]
 - Update BDK to version 0.20.0 [#169]

src/bdk.udl

@@ -1,9 +1,6 @@
 namespace bdk {
   [Throws=BdkError]
-  ExtendedKeyInfo generate_extended_key(Network network, WordCount word_count, string? password);
-
-  [Throws=BdkError]
-  ExtendedKeyInfo restore_extended_key(Network network, string mnemonic, string? password);
+  string generate_mnemonic(WordCount word_count);
 };
 
 [Error]
@@ -101,12 +98,6 @@ interface Transaction {
   Confirmed(TransactionDetails details, BlockTime confirmation);
 };
 
-dictionary ExtendedKeyInfo {
-  string mnemonic;
-  string xprv;
-  string fingerprint;
-};
-
 enum WordCount {
   "Words12",
   "Words15",
@@ -254,3 +245,31 @@ interface BumpFeeTxBuilder {
   [Throws=BdkError]
   PartiallySignedBitcoinTransaction finish([ByRef] Wallet wallet);
 };
+
+interface DerivationPath {
+  [Throws=BdkError]
+  constructor(string path);
+};
+
+interface DescriptorSecretKey {
+  [Throws=BdkError]
+  constructor(Network network, string mnemonic, string? password);
+
+  [Throws=BdkError]
+  DescriptorSecretKey derive(DerivationPath path);
+
+  DescriptorSecretKey extend(DerivationPath path);
+
+  DescriptorPublicKey as_public();
+
+  string as_string();
+};
+
+interface DescriptorPublicKey {
+  [Throws=BdkError]
+  DescriptorPublicKey derive(DerivationPath path);
+
+  DescriptorPublicKey extend(DerivationPath path);
+
+  string as_string();
+};