1 files changed, 100 insertions, 2 deletions

diff --git a/src/rpc/util.h b/src/rpc/util.h
index 0a3a156e45..1d1df2c635 100644
--- a/src/rpc/util.h
+++ b/src/rpc/util.h
@@ -9,14 +9,18 @@
 #include <script/standard.h>
 #include <univalue.h>
 
-#include <boost/variant/static_visitor.hpp>
-
 #include <string>
 #include <vector>
 
 class CKeyStore;
 class CPubKey;
 class CScript;
+struct InitInterfaces;
+
+//! Pointers to interfaces that need to be accessible from RPC methods. Due to
+//! limitations of the RPC framework, there's currently no direct way to pass in
+//! state to RPC method implementations.
+extern InitInterfaces* g_rpc_interfaces;
 
 CPubKey HexToPubKey(const std::string& hex_in);
 CPubKey AddrToPubKey(CKeyStore* const keystore, const std::string& addr_in);
@@ -24,4 +28,98 @@ CScript CreateMultisigRedeemscript(const int required, const std::vector<CPubKey
 
 UniValue DescribeAddress(const CTxDestination& dest);
 
+struct RPCArg {
+    enum class Type {
+        OBJ,
+        ARR,
+        STR,
+        NUM,
+        BOOL,
+        OBJ_USER_KEYS, //!< Special type where the user must set the keys e.g. to define multiple addresses; as opposed to e.g. an options object where the keys are predefined
+        AMOUNT,        //!< Special type representing a floating point amount (can be either NUM or STR)
+        STR_HEX,       //!< Special type that is a STR with only hex chars
+    };
+    const std::string m_name; //!< The name of the arg (can be empty for inner args)
+    const Type m_type;
+    const std::vector<RPCArg> m_inner; //!< Only used for arrays or dicts
+    const bool m_optional;
+    const std::string m_default_value; //!< Only used for optional args
+    const std::string m_description;
+    const std::string m_oneline_description; //!< Should be empty unless it is supposed to override the auto-generated summary line
+    const std::vector<std::string> m_type_str; //!< Should be empty unless it is supposed to override the auto-generated type strings. Vector length is either 0 or 2, m_type_str.at(0) will override the type of the value in a key-value pair, m_type_str.at(1) will override the type in the argument description.
+
+    RPCArg(
+        const std::string& name,
+        const Type& type,
+        const bool opt,
+        const std::string& default_val,
+        const std::string& description,
+        const std::string& oneline_description = "",
+        const std::vector<std::string>& type_str = {})
+        : m_name{name},
+          m_type{type},
+          m_optional{opt},
+          m_default_value{default_val},
+          m_description{description},
+          m_oneline_description{oneline_description},
+          m_type_str{type_str}
+    {
+        assert(type != Type::ARR && type != Type::OBJ);
+    }
+
+    RPCArg(
+        const std::string& name,
+        const Type& type,
+        const bool opt,
+        const std::string& default_val,
+        const std::string& description,
+        const std::vector<RPCArg>& inner,
+        const std::string& oneline_description = "",
+        const std::vector<std::string>& type_str = {})
+        : m_name{name},
+          m_type{type},
+          m_inner{inner},
+          m_optional{opt},
+          m_default_value{default_val},
+          m_description{description},
+          m_oneline_description{oneline_description},
+          m_type_str{type_str}
+    {
+        assert(type == Type::ARR || type == Type::OBJ);
+    }
+
+    /**
+     * Return the type string of the argument.
+     * Set oneline to allow it to be overrided by a custom oneline type string (m_oneline_description).
+     */
+    std::string ToString(bool oneline) const;
+    /**
+     * Return the type string of the argument when it is in an object (dict).
+     * Set oneline to get the oneline representation (less whitespace)
+     */
+    std::string ToStringObj(bool oneline) const;
+    /**
+     * Return the description string, including the argument type and whether
+     * the argument is required.
+     * implicitly_required is set for arguments in an array, which are neither optional nor required.
+     */
+    std::string ToDescriptionString(bool implicitly_required = false) const;
+};
+
+class RPCHelpMan
+{
+public:
+    RPCHelpMan(const std::string& name, const std::string& description, const std::vector<RPCArg>& args)
+        : m_name{name}, m_description{description}, m_args{args}
+    {
+    }
+
+    std::string ToString() const;
+
+private:
+    const std::string m_name;
+    const std::string m_description;
+    const std::vector<RPCArg> m_args;
+};
+
 #endif // BITCOIN_RPC_UTIL_H