template-ify the cbor stuff

1 files changed, 85 insertions, 7 deletions

diff --git a/src/cbor/include/cbor_decoder.hpp b/src/cbor/include/cbor_decoder.hpp
index 249db9cc..39151ca8 100644
--- a/src/cbor/include/cbor_decoder.hpp
+++ b/src/cbor/include/cbor_decoder.hpp
@@ -1,15 +1,61 @@
 #pragma once
 
+#include <stdint.h>
 #include <cstdint>
+
 namespace cbor {
 
+  static auto parse_stdstring(CborValue *val, std::string *out) -> CborError {
+        uint8_t *buf; size_t len;
+        CborError err = cbor_value_dup_byte_string(val, &buf, &len, NULL);
+        if (err != CborNoError) {
+          return err;
+        }
+        *out = std::move(std::string(buf, len));
+        free(buf);
+        return err
+  }
+
   class ArrayDecoder {
     public:
-      static auto Create(uint8_t *buffer, size_t buffer_len) -> cpp::result<std::unique_ptr<ArrayDecoder>, CborError>;
+      static auto Create(uint8_t *buffer, size_t buffer_len)
+        -> cpp::result<std::unique_ptr<ArrayDecoder>, CborError>;
+
+      template<typename T>
+      auto NextValue() -> cpp::result<T, CborError>;
 
-      auto ParseString() -> cpp::result<std::string, CborError>;
-      auto ParseUnsigned() -> cpp::result<uint32_t, CborError>;
-      auto ParseSigned() -> cpp::result<int32_t, CborError>;
+      template<> auto NextValue() -> cpp::result<int64_t, CborError> {
+        return NextValue(&cbor_value_is_integer, &cbor_value_get_int);
+      }
+      template<> auto NextValue() -> cpp::result<uint64_t, CborError> {
+        return NextValue(&cbor_value_is_unsigned_integer, &cbor_value_get_uint64);
+      }
+      template<> auto NextValue() -> cpp::result<std::string, CborError> {
+        return NextValue(&cbor_value_is_byte_string, &parse_stdstring);
+      }
+
+      template <typename T>
+      auto NextValue(
+          bool(*is_valid)(CborValue*),
+          CborError(*parse)(CborValue*, T*)) -> cpp::result<T, CborError> {
+        if (error_ != CborNoError) {
+          return cpp::fail(error_);
+        }
+        if (!is_valid(&it_)) {
+          error_ = CborErrorIllegalType;
+          return cpp::fail(error_);
+        }
+        T ret;
+        error_ = parse(&it_, &ret);
+        if (error_ != CborNoError) {
+          return cpp::fail(error_);
+        }
+        error_ = cbor_value_advance(&it_);
+        if (error_ != CborNoError) {
+          return cpp::fail(error_);
+        }
+        return ret;
+      }
 
       auto Failed() -> CborError { return error_; }
 
@@ -27,9 +73,41 @@ namespace cbor {
     public:
       static auto Create(uint8_t *buffer, size_t buffer_len) -> cpp::result<std::unique_ptr<MapDecoder>, CborError>;
 
-      auto FindString(const std::string &key) -> std::optional<std::string>;
-      auto FindUnsigned(const std::string &key) -> std::optional<uint32_t>;
-      auto FindSigned(const std::string &key) -> std::optional<int32_t>;
+      template<typename T>
+      auto FindValue(const std::string &key) -> std::optional<T>;
+
+      template<> auto FindValue(const std::string &key) -> std::optional<int64_t> {
+        return FindValue(key, &cbor_value_is_integer, &cbor_value_get_int);
+      }
+      template<> auto FindValue(const std::string &key) -> std::optional<uint64_t> {
+        return FindValue(key, &cbor_value_is_unsigned_integer, &cbor_value_get_uint64);
+      }
+      template<> auto FindValue(const std::string &key) -> std::optional<std::string> {
+        return FindValue(key, &cbor_value_is_byte_string, &parse_stdstring);
+      }
+
+      template <typename T>
+      auto FindValue(
+          const std::string &key,
+          bool(*is_valid)(CborValue*),
+          CborError(*parse)(CborValue*, T*)) -> std::optional<T> {
+        if (error_ != CborNoError) {
+          return {};
+        }
+        if (cbor_value_map_find_value(&it_, key.c_str(), &val) != CborNoError) {
+          return {};
+        }
+        if (!is_valid(&val)) {
+          error_ = CborErrorIllegalType;
+          return {};
+        }
+        T ret;
+        error_ = parse(&val, &ret);
+        if (error_ != CborNoError) {
+          return cpp::fail(error_);
+        }
+        return ret;
+      }
 
       auto Failed() -> CborError { return error_; }