Fix Wallet.broadcast function, now returns a tx id as a hex string

cc3736809a Fix memory database configuration enum (thunderbiscuit)

Pull request description:

  The `DatabaseConfig.Memory` enum currently requires a "junk" string argument which is not used when creating the wallet:

  ```rust
  // lib.rs line 24
  pub enum DatabaseConfig {
      Memory { junk: String },
      Sled { config: SledDbConfiguration },
  }

  // lib.rs line 209
  impl Wallet {
      fn new(
          descriptor: String,
          change_descriptor: Option<String>,
          network: Network,
          database_config: DatabaseConfig,
          blockchain_config: BlockchainConfig,
      ) -> Result<Self, BdkError> {
          let any_database_config = match database_config {
              DatabaseConfig::Memory { .. } => AnyDatabaseConfig::Memory(()),
              DatabaseConfig::Sled { config } => AnyDatabaseConfig::Sled(config),
          };
  ```

  Which translates to the udl file like this:
  ```txt
  [Enum]
  interface DatabaseConfig {
    Memory(string junk);
    Sled(SledDbConfiguration config);
  };
  ```

  According to the [docs from uniffi-rs](https://mozilla.github.io/uniffi-rs/udl/enumerations.html) the `interface` here is required because the enums have named fields. But after testing I found that we can declare the udl file like so, and remove the requirement for the `junk` argument:
  ```txt
  [Enum]
  interface DatabaseConfig {
    Memory();
    Sled(SledDbConfiguration config);
  };
  ```

  On the Rust side we then have
  ```rust
  pub enum DatabaseConfig {
      Memory,
      Sled { config: SledDbConfiguration },
  }
  ```

  And the resulting bindings go from (note that the bindings transform the enum into a sealed class rather than a Kotlin enum)
  ```kotlin
  sealed class DatabaseConfig  {

      data class Memory(
          val junk: String
          ) : DatabaseConfig()

      data class Sled(
          val config: SledDbConfiguration
          ) : DatabaseConfig()
  ```
  to
  ```kotlin
  sealed class DatabaseConfig  {
      object Memory : DatabaseConfig()

      data class Sled(
          val config: SledDbConfiguration
          ) : DatabaseConfig()
  ```

  Which makes the API simpler to use, and removes the confusion created by having to provide an empty string (or not know what we're supposed to provide) to the `Memory()` enum.

  The final call-site looks like this:
  ```kotlin
      fun onlineWalletSyncGetBalance() {
          // val db = DatabaseConfig.Memory("")
          val db = DatabaseConfig.Memory
          val client = BlockchainConfig.Electrum(
              ElectrumConfig(
                  "ssl://electrum.blockstream.info:60002",
                  null,
                  5u,
                  null,
                  100u
              )
          )
          val wallet = Wallet(descriptor, null, Network.REGTEST, databaseConfig, blockchainConfig)
          wallet.sync(LogProgress(), null)
          val balance = wallet.getBalance()
          assertTrue(balance > 0u)
      }
  ```

  All tests run well on my side of things, but I'm opening this more as a discussion piece because I wasn't sure if there were other reasons for the choice of providing the argument to the `Memory` enum, or other design choices I'm not aware of. Any thoughts on this @artfuldev? I think you were the one who wrote the initial enum.

Top commit has no ACKs.

Tree-SHA512: 135e5943039a08522773f721a7cf6bbb93bd5bb9394bf42a30bab5f3e16fd35ce078056756e020a666d4f574d74080bc3404cc81809c0d7e0afe5c9471878425

.editorconfig

@@ -0,0 +1,29 @@
+root = true
+
+[*]
+charset = utf-8
+end_of_line = lf
+indent_size = 2
+indent_style = space
+trim_trailing_whitespace = true
+insert_final_newline = true
+
+[*.md]
+trim_trailing_whitespace = false
+
+[*.rs]
+indent_size = 4
+
+[*.kt]
+indent_size = 4
+
+[*.gradle]
+indent_size = 4
+
+[tests/**/*.rs]
+charset = utf-8
+end_of_line = unset
+indent_size = unset
+indent_style = unset
+trim_trailing_whitespace = unset
+insert_final_newline = unset

.gitignore

@@ -1,4 +1,16 @@
-/target
-*.h
-/main
-/Cargo.lock
+target
+build
+Cargo.lock
+/bindings/bdk-kotlin/local.properties
+.gradle
+wallet_db
+bdk_ffi_test
+local.properties
+*.log
+*.dylib
+*.so
+.DS_Store
+testdb
+xcuserdata
+.lsp
+.clj-kondo

CHANGELOG.md

@@ -0,0 +1,37 @@
+# Changelog
+All notable changes to this project will be documented in this file.
+
+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]
+
+- Fix Wallet.broadcast function, now returns a tx id as a hex string
+
+## [v0.4.0]
+
+- Add dual license MIT and Apache 2.0
+- Add sqlite database support
+- Fix memory database configuration enum, remove junk field
+
+## [v0.3.1]
+
+- Remove hard coded sync progress value (was always returning 21.0)
+
+## [v0.3.0]
+
+- Move bdk-kotlin bindings and ios example to separate repos
+- Add bin to generate Python bindings
+- Add `PartiallySignedBitcoinTransaction::deserialize` function as named constructor to decode from a string per [BIP 0174]
+- Add `PartiallySignedBitcoinTransaction::serialize` function to encode to a string per [BIP 0174]
+- Remove `PartiallySignedBitcoinTransaction.details` struct field
+
+[BIP 0174]:https://github.com/bitcoin/bips/blob/master/bip-0174.mediawiki#encoding
+
+## [v0.2.0]
+
+[unreleased]: https://github.com/bitcoindevkit/bdk-ffi/compare/v0.4.0...HEAD
+[v0.4.0]: https://github.com/bitcoindevkit/bdk-ffi/compare/v0.3.1...v0.4.0
+[v0.3.1]: https://github.com/bitcoindevkit/bdk-ffi/compare/v0.3.0...v0.3.1
+[v0.3.0]: https://github.com/bitcoindevkit/bdk-ffi/compare/v0.2.0...v0.3.0
+[v0.2.0]: https://github.com/bitcoindevkit/bdk-ffi/compare/v0.0.0...v0.2.0

Cargo.toml

@@ -1,16 +1,32 @@
 [package]
-name = "bdk_ffi"
-version = "0.1.0"
-authors = ["Steve Myers <steve@notmandatory.org>"]
+name = "bdk-ffi"
+version = "0.4.1"
+authors = ["Steve Myers <steve@notmandatory.org>", "Sudarsan Balaji <sudarsan.balaji@artfuldev.com>"]
 edition = "2018"
 
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 [lib]
-crate-type = ["staticlib"]
+crate-type = ["staticlib", "cdylib"]
+name = "bdkffi"
 
 [dependencies]
-bdk = { version = "^0.7", feature = ["all-keys"] }
-safer-ffi = { version = "*", features = ["proc_macros"]}
+bdk = { version = "0.14", features = ["all-keys", "use-esplora-ureq", "sqlite"] }
+
+# TODO remove when bdk "sqlite-bundled" feature added
+rusqlite = { version = "0.25.3", features = ["bundled"] }
+
+uniffi_macros = { version = "0.16.0", features = ["builtin-bindgen"] }
+uniffi = { version = "0.16.0", features = ["builtin-bindgen"] }
+thiserror = "1.0"
+anyhow = "=1.0.45" # remove after upgrading to next version of uniffi
+
+uniffi_bindgen = { version = "0.16.0", optional = true }
+
+[build-dependencies]
+uniffi_build = { version = "0.16.0", features = ["builtin-bindgen"] }
 
 [features]
-c-headers = ["safer-ffi/headers"]
+generate-python = ["uniffi_bindgen"]
+
+[[bin]]
+name = "generate"

LICENSE

@@ -0,0 +1,14 @@
+This software is licensed under [Apache 2.0](LICENSE-APACHE) or
+[MIT](LICENSE-MIT), at your option.
+
+Some files retain their own copyright notice, however, for full authorship
+information, see version control history.
+
+Except as otherwise noted in individual files, all files in this repository are
+licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+http://www.apache.org/licenses/LICENSE-2.0> or the MIT license <LICENSE-MIT or
+http://opensource.org/licenses/MIT>, at your option.
+
+You may not use, copy, modify, merge, publish, distribute, sublicense, and/or
+sell copies of this software or any files in this repository except in
+accordance with one or both of these licenses.

LICENSE-APACHE

@@ -0,0 +1,201 @@
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LICENSE-MIT

@@ -0,0 +1,16 @@
+Permission is hereby granted, free of charge, to any person obtaining a copy of
+this software and associated documentation files (the "Software"), to deal in
+the Software without restriction, including without limitation the rights to
+use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+the Software, and to permit persons to whom the Software is furnished to do so,
+subject to the following conditions:
+
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+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

README.md

@@ -0,0 +1,67 @@
+# Native language bindings for BDK
+
+This repository contains source code for generating native language bindings for the rust based 
+[bdk] library which is the central artifact of the [Bitcoin Dev Kit] project.
+
+Each supported language has it's own repository that includes this project as a [git submodule]. 
+The rust code in this project is a wrapper around the [bdk] library to expose it's APIs in a 
+uniform way using the [mozilla/uniffi-rs] bindings generator for each supported target language.
+
+## Supported target languages and platforms
+
+The below repositories include instructions for using, building, and publishing the native 
+language binding for [bdk] supported by this project.
+
+| Language | Platform     | Repository   |
+| -------- | ------------ | ------------ |
+| Kotlin   | jvm          | [bdk-kotlin] |
+| Kotlin   | android      | [bdk-kotlin] |
+| Swift    | iOS, macOS   | [bdk-swift]  |
+| Python   | linux, macOS | [bdk-python] |
+
+[bdk]: https://github.com/bitcoindevkit/bdk
+[Bitcoin Dev Kit]: https://github.com/bitcoindevkit
+[git submodule]: https://git-scm.com/book/en/v2/Git-Tools-Submodules
+[uniffi-rs]: https://github.com/mozilla/uniffi-rs
+
+[bdk-kotlin]: https://github.com/bitcoindevkit/bdk-kotlin
+[bdk-swift]: https://github.com/bitcoindevkit/bdk-swift
+[bdk-python]: https://github.com/thunderbiscuit/bdk-python
+
+## Contributing
+
+### Install uniffi-bindgen cli tool
+
+Install the uniffi-bindgen binary on your system using:
+
+`cargo install uniffi_bindgen`
+
+The version must be the same as the `uniffi` dependency in `Cargo.toml`.
+
+### Adding new structs and functions
+
+See the [UniFFI User Guide](https://mozilla.github.io/uniffi-rs/)
+
+#### For pass by value objects
+
+1. create new rust struct with only fields that are supported UniFFI types
+1. update mapping `bdk.udl` file with new `dictionary`
+
+#### For pass by reference values 
+
+1. create wrapper rust struct/impl with only fields that are `Sync + Send`
+1. update mapping `bdk.udl` file with new `interface`
+
+## Goals
+
+1. Language bindings should feel idiomatic in target languages/platforms
+1. Adding new targets should be easy
+1. Getting up and running should be easy
+1. Contributing should be easy
+1. Get it right, then automate
+
+## Thanks
+
+This project is made possible thanks to the wonderful work by the [mozilla/uniffi-rs] team.
+
+[mozilla/uniffi-rs]: https://github.com/mozilla/uniffi-rs

build.rs

@@ -0,0 +1,3 @@
+fn main() {
+    uniffi_build::generate_scaffolding("src/bdk.udl").unwrap();
+}

main.c

@@ -1,13 +0,0 @@
-#include <stdlib.h>
-
-#include "bdk_ffi.h"
-
-int main (int argc, char const * const argv[])
-{
-    Point_t * a = new_point(84,45);
-    Point_t * b = new_point(0.0,39.0);
-    Point_t * m = mid_point(a, b);
-    print_point(m);
-    print_point(NULL);
-    return EXIT_SUCCESS;
-}

src/bdk.udl

@@ -0,0 +1,157 @@
+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);
+};
+
+[Error]
+enum BdkError {
+  "InvalidU32Bytes",
+  "Generic",
+  "ScriptDoesntHaveAddressForm",
+  "NoRecipients",
+  "NoUtxosSelected",
+  "OutputBelowDustLimit",
+  "InsufficientFunds",
+  "BnBTotalTriesExceeded",
+  "BnBNoExactMatch",
+  "UnknownUtxo",
+  "TransactionNotFound",
+  "TransactionConfirmed",
+  "IrreplaceableTransaction",
+  "FeeRateTooLow",
+  "FeeTooLow",
+  "FeeRateUnavailable",
+  "MissingKeyOrigin",
+  "Key",
+  "ChecksumMismatch",
+  "SpendingPolicyRequired",
+  "InvalidPolicyPathError",
+  "Signer",
+  "InvalidNetwork",
+  "InvalidProgressValue",
+  "ProgressUpdateError",
+  "InvalidOutpoint",
+  "Descriptor",
+  "AddressValidator",
+  "Encode",
+  "Miniscript",
+  "Bip32",
+  "Secp256k1",
+  "Json",
+  "Hex",
+  "Psbt",
+  "PsbtParse",
+  "Electrum",
+  "Esplora",
+  "Sled",
+  "Rusqlite",
+};
+
+enum Network {
+  "Bitcoin",
+  "Testnet",
+  "Signet",
+  "Regtest",
+};
+
+dictionary SledDbConfiguration {
+  string path;
+  string tree_name;
+};
+
+dictionary SqliteDbConfiguration {
+  string path;
+};
+
+[Enum]
+interface DatabaseConfig {
+  Memory();
+  Sled(SledDbConfiguration config);
+  Sqlite(SqliteDbConfiguration config);
+};
+
+dictionary TransactionDetails {
+    u64? fees;
+    u64 received;
+    u64 sent;
+    string txid;
+};
+
+dictionary BlockTime {
+    u32 height;
+    u64 timestamp;
+};
+
+[Enum]
+interface Transaction {
+  Unconfirmed(TransactionDetails details);
+  Confirmed(TransactionDetails details, BlockTime confirmation);
+};
+
+dictionary ElectrumConfig {
+  string url;
+  string? socks5;
+  u8 retry;
+  u8? timeout;
+  u64 stop_gap;
+};
+
+dictionary EsploraConfig {
+  string base_url;
+  string? proxy;
+  u64 timeout_read;
+  u64 timeout_write;
+  u64 stop_gap;
+};
+
+[Enum]
+interface BlockchainConfig {
+  Electrum(ElectrumConfig config);
+  Esplora(EsploraConfig config);
+};
+
+callback interface BdkProgress {
+  void update(f32 progress, string? message);
+};
+
+interface Wallet {
+  [Throws=BdkError]
+  constructor(string descriptor, string? change_descriptor, Network network, DatabaseConfig database_config, BlockchainConfig blockchain_config);
+  string get_new_address();
+  string get_last_unused_address();
+  [Throws=BdkError]
+  u64 get_balance();
+  [Throws=BdkError]
+  void sign([ByRef] PartiallySignedBitcoinTransaction psbt);
+  [Throws=BdkError]
+  sequence<Transaction> get_transactions();
+  Network get_network();
+  [Throws=BdkError]
+  void sync(BdkProgress progress_update, u32? max_address_param);
+  [Throws=BdkError]
+  string broadcast([ByRef] PartiallySignedBitcoinTransaction psbt);
+};
+
+interface PartiallySignedBitcoinTransaction {
+  [Throws=BdkError]
+  constructor([ByRef] Wallet wallet, string recipient, u64 amount, float? fee_rate);
+  [Name=deserialize,Throws=BdkError]
+  constructor(string psbt_base64);
+  string serialize();
+};
+
+dictionary ExtendedKeyInfo {
+  string mnemonic;
+  string xprv;
+  string fingerprint;
+};
+
+enum WordCount {
+  "Words12",
+  "Words15",
+  "Words18",
+  "Words21",
+  "Words24",
+};

src/bin/generate.rs

@@ -0,0 +1,67 @@
+pub const BDK_UDL: &str = "src/bdk.udl";
+
+#[cfg(feature = "generate-python")]
+fn fixup_python_lib_path<O: AsRef<std::path::Path>>(
+    out_dir: O,
+    lib_name: &str,
+) -> Result<(), Box<dyn std::error::Error>> {
+    use std::fs;
+    use std::io::Write;
+
+    const LOAD_INDIRECT_DEF: &str = "def loadIndirect():";
+
+    let bindings_file = out_dir.as_ref().join("bdk.py");
+    let mut data = fs::read_to_string(&bindings_file)?;
+
+    let pos = data.find(LOAD_INDIRECT_DEF).expect(&format!(
+        "loadIndirect not found in `{}`",
+        bindings_file.display()
+    ));
+    let range = pos..pos + LOAD_INDIRECT_DEF.len();
+
+    let replacement = format!(
+        r#"
+def loadIndirect():
+    import glob
+    return getattr(ctypes.cdll, glob.glob(os.path.join(os.path.dirname(os.path.abspath(__file__)), '{}.*'))[0])
+
+def _loadIndirectOld():"#,
+        lib_name
+    );
+    data.replace_range(range, &replacement);
+
+    let mut file = fs::OpenOptions::new()
+        .write(true)
+        .truncate(true)
+        .open(&bindings_file)?;
+    file.write(data.as_bytes())?;
+
+    Ok(())
+}
+
+#[cfg(feature = "generate-python")]
+fn generate_python() -> Result<(), Box<dyn std::error::Error>> {
+    use std::env;
+
+    let out_path = env::var("GENERATE_PYTHON_BINDINGS_OUT")
+        .map_err(|_| String::from("`GENERATE_PYTHON_BINDINGS_OUT` env variable missing"))?;
+    uniffi_bindgen::generate_bindings(
+        &format!("{}/{}", env!("CARGO_MANIFEST_DIR"), BDK_UDL),
+        None,
+        vec!["python"],
+        Some(&out_path),
+        false,
+    )?;
+
+    if let Some(name) = env::var("GENERATE_PYTHON_BINDINGS_FIXUP_LIB_PATH").ok() {
+        fixup_python_lib_path(&out_path, &name)?;
+    }
+
+    Ok(())
+}
+
+fn main() -> Result<(), Box<dyn std::error::Error>> {
+    #[cfg(feature = "generate-python")]
+    generate_python()?;
+    Ok(())
+}

src/lib.rs

@@ -1,47 +1,316 @@
-use ::safer_ffi::prelude::*;
+use bdk::bitcoin::hashes::hex::ToHex;
+use bdk::bitcoin::secp256k1::Secp256k1;
+use bdk::bitcoin::util::psbt::PartiallySignedTransaction;
+use bdk::bitcoin::{Address, Network};
+use bdk::blockchain::any::{AnyBlockchain, AnyBlockchainConfig};
+use bdk::blockchain::Progress;
+use bdk::blockchain::{
+    electrum::ElectrumBlockchainConfig, esplora::EsploraBlockchainConfig, ConfigurableBlockchain,
+};
+use bdk::database::any::{AnyDatabase, SledDbConfiguration, SqliteDbConfiguration};
+use bdk::database::{AnyDatabaseConfig, ConfigurableDatabase};
+use bdk::keys::bip39::{Language, Mnemonic, WordCount};
+use bdk::keys::{DerivableKey, ExtendedKey, GeneratableKey, GeneratedKey};
+use bdk::miniscript::BareCtx;
+use bdk::wallet::AddressIndex;
+use bdk::{BlockTime, Error, FeeRate, SignOptions, Wallet as BdkWallet};
+use std::convert::TryFrom;
+use std::str::FromStr;
+use std::sync::{Mutex, MutexGuard};
 
-/// A `struct` usable from both Rust and C
-#[derive_ReprC]
-#[repr(C)]
-#[derive(Debug, Clone, Copy)]
-pub struct Point {
-    x: f64,
-    y: f64,
+uniffi_macros::include_scaffolding!("bdk");
+
+type BdkError = Error;
+
+pub enum DatabaseConfig {
+    Memory,
+    Sled { config: SledDbConfiguration },
+    Sqlite { config: SqliteDbConfiguration },
 }
 
-/* Export a Rust function to the C world. */
-/// Returns the middle point of `[a, b]`.
-#[ffi_export]
-fn mid_point(a: Option<repr_c::Box<Point>>, b: Option<repr_c::Box<Point>>) -> repr_c::Box<Point> {
-    let a = a.unwrap();
-    let b = b.unwrap();
-    repr_c::Box::new(Point {
-        x: (a.x + b.x) / 2.,
-        y: (a.y + b.y) / 2.,
+pub struct ElectrumConfig {
+    pub url: String,
+    pub socks5: Option<String>,
+    pub retry: u8,
+    pub timeout: Option<u8>,
+    pub stop_gap: u64,
+}
+
+pub struct EsploraConfig {
+    pub base_url: String,
+    pub proxy: Option<String>,
+    pub timeout_read: u64,
+    pub timeout_write: u64,
+    pub stop_gap: u64,
+}
+
+pub enum BlockchainConfig {
+    Electrum { config: ElectrumConfig },
+    Esplora { config: EsploraConfig },
+}
+
+trait WalletHolder<B> {
+    fn get_wallet(&self) -> MutexGuard<BdkWallet<B, AnyDatabase>>;
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Default)]
+pub struct TransactionDetails {
+    pub fees: Option<u64>,
+    pub received: u64,
+    pub sent: u64,
+    pub txid: String,
+}
+
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub enum Transaction {
+    Unconfirmed {
+        details: TransactionDetails,
+    },
+    Confirmed {
+        details: TransactionDetails,
+        confirmation: BlockTime,
+    },
+}
+
+impl From<&bdk::TransactionDetails> for TransactionDetails {
+    fn from(x: &bdk::TransactionDetails) -> TransactionDetails {
+        TransactionDetails {
+            fees: x.fee,
+            txid: x.txid.to_string(),
+            received: x.received,
+            sent: x.sent,
+        }
+    }
+}
+
+impl From<&bdk::TransactionDetails> for Transaction {
+    fn from(x: &bdk::TransactionDetails) -> Transaction {
+        match x.confirmation_time.clone() {
+            Some(block_time) => Transaction::Confirmed {
+                details: TransactionDetails::from(x),
+                confirmation: block_time,
+            },
+            None => Transaction::Unconfirmed {
+                details: TransactionDetails::from(x),
+            },
+        }
+    }
+}
+
+trait WalletOperations<B>: WalletHolder<B> {
+    fn get_new_address(&self) -> String {
+        self.get_wallet()
+            .get_address(AddressIndex::New)
+            .unwrap()
+            .address
+            .to_string()
+    }
+
+    fn get_last_unused_address(&self) -> String {
+        self.get_wallet()
+            .get_address(AddressIndex::LastUnused)
+            .unwrap()
+            .address
+            .to_string()
+    }
+
+    fn get_balance(&self) -> Result<u64, Error> {
+        self.get_wallet().get_balance()
+    }
+
+    fn sign(&self, psbt: &PartiallySignedBitcoinTransaction) -> Result<(), Error> {
+        let mut psbt = psbt.internal.lock().unwrap();
+        let finalized = self.get_wallet().sign(&mut psbt, SignOptions::default())?;
+        match finalized {
+            true => Ok(()),
+            false => Err(BdkError::Generic(format!(
+                "transaction signing not finalized {:?}",
+                psbt
+            ))),
+        }
+    }
+
+    fn get_transactions(&self) -> Result<Vec<Transaction>, Error> {
+        let transactions = self.get_wallet().list_transactions(true)?;
+        Ok(transactions.iter().map(Transaction::from).collect())
+    }
+}
+
+struct Wallet {
+    wallet_mutex: Mutex<BdkWallet<AnyBlockchain, AnyDatabase>>,
+}
+
+pub trait BdkProgress: Send + Sync {
+    fn update(&self, progress: f32, message: Option<String>);
+}
+
+struct BdkProgressHolder {
+    progress_update: Box<dyn BdkProgress>,
+}
+
+impl Progress for BdkProgressHolder {
+    fn update(&self, progress: f32, message: Option<String>) -> Result<(), Error> {
+        self.progress_update.update(progress, message);
+        Ok(())
+    }
+}
+
+struct PartiallySignedBitcoinTransaction {
+    internal: Mutex<PartiallySignedTransaction>,
+}
+
+impl PartiallySignedBitcoinTransaction {
+    fn new(
+        wallet: &Wallet,
+        recipient: String,
+        amount: u64,
+        fee_rate: Option<f32>, // satoshis per vbyte
+    ) -> Result<Self, Error> {
+        let wallet = wallet.get_wallet();
+        match Address::from_str(&recipient) {
+            Ok(address) => {
+                let (psbt, _details) = {
+                    let mut builder = wallet.build_tx();
+                    builder.add_recipient(address.script_pubkey(), amount);
+                    if let Some(sat_per_vb) = fee_rate {
+                        builder.fee_rate(FeeRate::from_sat_per_vb(sat_per_vb));
+                    }
+                    builder.finish()?
+                };
+                Ok(PartiallySignedBitcoinTransaction {
+                    internal: Mutex::new(psbt),
+                })
+            }
+            Err(..) => Err(BdkError::Generic(
+                "failed to read wallet address".to_string(),
+            )),
+        }
+    }
+
+    pub fn deserialize(psbt_base64: String) -> Result<Self, Error> {
+        let psbt: PartiallySignedTransaction = PartiallySignedTransaction::from_str(&psbt_base64)?;
+        Ok(PartiallySignedBitcoinTransaction {
+            internal: Mutex::new(psbt),
+        })
+    }
+
+    pub fn serialize(&self) -> String {
+        let psbt = self.internal.lock().unwrap().clone();
+        psbt.to_string()
+    }
+}
+
+impl WalletHolder<AnyBlockchain> for Wallet {
+    fn get_wallet(&self) -> MutexGuard<BdkWallet<AnyBlockchain, AnyDatabase>> {
+        self.wallet_mutex.lock().expect("wallet")
+    }
+}
+
+impl WalletOperations<AnyBlockchain> for Wallet {}
+
+impl Wallet {
+    fn new(
+        descriptor: String,
+        change_descriptor: Option<String>,
+        network: Network,
+        database_config: DatabaseConfig,
+        blockchain_config: BlockchainConfig,
+    ) -> Result<Self, BdkError> {
+        let any_database_config = match database_config {
+            DatabaseConfig::Memory => AnyDatabaseConfig::Memory(()),
+            DatabaseConfig::Sled { config } => AnyDatabaseConfig::Sled(config),
+            DatabaseConfig::Sqlite { config } => AnyDatabaseConfig::Sqlite(config),
+        };
+        let any_blockchain_config = match blockchain_config {
+            BlockchainConfig::Electrum { config } => {
+                AnyBlockchainConfig::Electrum(ElectrumBlockchainConfig {
+                    retry: config.retry,
+                    socks5: config.socks5,
+                    timeout: config.timeout,
+                    url: config.url,
+                    stop_gap: usize::try_from(config.stop_gap).unwrap(),
+                })
+            }
+            BlockchainConfig::Esplora { config } => {
+                AnyBlockchainConfig::Esplora(EsploraBlockchainConfig {
+                    base_url: config.base_url,
+                    proxy: config.proxy,
+                    timeout_read: config.timeout_read,
+                    timeout_write: config.timeout_write,
+                    stop_gap: usize::try_from(config.stop_gap).unwrap(),
+                })
+            }
+        };
+        let database = AnyDatabase::from_config(&any_database_config)?;
+        let blockchain = AnyBlockchain::from_config(&any_blockchain_config)?;
+        let wallet_mutex = Mutex::new(BdkWallet::new(
+            &descriptor,
+            change_descriptor.to_owned().as_ref(),
+            network,
+            database,
+            blockchain,
+        )?);
+        Ok(Wallet { wallet_mutex })
+    }
+
+    fn get_network(&self) -> Network {
+        self.get_wallet().network()
+    }
+
+    fn sync(
+        &self,
+        progress_update: Box<dyn BdkProgress>,
+        max_address_param: Option<u32>,
+    ) -> Result<(), BdkError> {
+        self.get_wallet()
+            .sync(BdkProgressHolder { progress_update }, max_address_param)
+    }
+
+    fn broadcast(&self, psbt: &PartiallySignedBitcoinTransaction) -> Result<String, Error> {
+        let tx = psbt.internal.lock().unwrap().clone().extract_tx();
+        let txid = self.get_wallet().broadcast(&tx)?;
+        Ok(txid.to_hex())
+    }
+}
+
+pub struct ExtendedKeyInfo {
+    mnemonic: String,
+    xprv: String,
+    fingerprint: String,
+}
+
+fn generate_extended_key(
+    network: Network,
+    word_count: WordCount,
+    password: Option<String>,
+) -> Result<ExtendedKeyInfo, Error> {
+    let mnemonic: GeneratedKey<_, BareCtx> =
+        Mnemonic::generate((word_count, Language::English)).unwrap();
+    let mnemonic = mnemonic.into_key();
+    let xkey: ExtendedKey = (mnemonic.clone(), password).into_extended_key()?;
+    let xprv = xkey.into_xprv(network).unwrap();
+    let fingerprint = xprv.fingerprint(&Secp256k1::new());
+    Ok(ExtendedKeyInfo {
+        mnemonic: mnemonic.to_string(),
+        xprv: xprv.to_string(),
+        fingerprint: fingerprint.to_string(),
     })
 }
 
-/// Pretty-prints a point using Rust's formatting logic.
-#[ffi_export]
-fn print_point(point: Option<repr_c::Box<Point>>) {
-    println!("{:?}", point);
+fn restore_extended_key(
+    network: Network,
+    mnemonic: String,
+    password: Option<String>,
+) -> Result<ExtendedKeyInfo, Error> {
+    let mnemonic = Mnemonic::parse_in(Language::English, mnemonic).unwrap();
+    let xkey: ExtendedKey = (mnemonic.clone(), password).into_extended_key()?;
+    let xprv = xkey.into_xprv(network).unwrap();
+    let fingerprint = xprv.fingerprint(&Secp256k1::new());
+    Ok(ExtendedKeyInfo {
+        mnemonic: mnemonic.to_string(),
+        xprv: xprv.to_string(),
+        fingerprint: fingerprint.to_string(),
+    })
 }
 
-#[ffi_export]
-fn new_point(x: f64, y: f64) -> repr_c::Box<Point> {
-    repr_c::Box::new(Point { x, y })
-}
-
-#[ffi_export]
-fn free_point(point: Option<repr_c::Box<Point>>) {
-    drop(point)
-}
-
-/// The following test function is necessary for the header generation.
-#[::safer_ffi::cfg_headers]
-#[test]
-fn generate_headers() -> ::std::io::Result<()> {
-    ::safer_ffi::headers::builder()
-        .to_file("bdk_ffi.h")?
-        .generate()
-}
+uniffi::deps::static_assertions::assert_impl_all!(Wallet: Sync, Send);

uniffi.toml

@@ -0,0 +1,12 @@
+[bindings.kotlin]
+package_name = "org.bitcoindevkit"
+cdylib_name = "bdkffi"
+
+[bindings.python]
+cdylib_name = "bdkffi"
+
+[bindings.ruby]
+cdylib_name = "bdkffi"
+
+[bindings.swift]
+cdylib_name = "bdkffi"