added API handler class

1 files changed, 136 insertions, 0 deletions

diff --git a/src/hearthstoneAPIHandler.cpp b/src/hearthstoneAPIHandler.cpp
new file mode 100644
index 0000000..78f084b
--- /dev/null
+++ b/src/hearthstoneAPIHandler.cpp
@@ -0,0 +1,136 @@
+#include "hearthstoneAPIHandler.h"
+#include <chrono>
+#include <curl/curl.h>
+#include <format>
+#include <fstream>
+#include <iostream>
+#include <regex>
+
+HearthstoneAPIHandler::HearthstoneAPIHandler()
+    : m_access_token(get_valid_token()), m_header(generate_request_header()) {}
+
+size_t HearthstoneAPIHandler::curl_callback_token_request(void *t_contents,
+                                                          size_t t_size,
+                                                          size_t t_nmemb,
+                                                          std::string *t_s) {
+    size_t newLength = t_size * t_nmemb;
+    try {
+        t_s->append((char *)t_contents, newLength);
+    } catch (std::bad_alloc &e) {
+        // handle memory problem
+        return 0;
+    }
+    return newLength;
+}
+
+std::chrono::hours HearthstoneAPIHandler::get_current_time() {
+    return std::chrono::duration_cast<std::chrono::hours>(
+        std::chrono::utc_clock::now().time_since_epoch());
+}
+
+std::string
+HearthstoneAPIHandler::extract_string_with_regex(const std::string &t_str,
+                                                 const std::string t_regex) {
+    std::regex regex(t_regex);
+    auto it = std::sregex_iterator(t_str.begin(), t_str.end(), regex);
+    std::smatch match = *it;
+    return match[1].str();
+}
+
+void HearthstoneAPIHandler::write_new_token_info_to_file(
+    const std::string &file_path) {
+    std::ofstream token_file(file_path);
+    CURL *curl = curl_easy_init();
+    std::string token_info;
+    if (curl) {
+        curl_easy_setopt(curl, CURLOPT_URL, "https://oauth.battle.net/token");
+        curl_easy_setopt(curl, CURLOPT_SSL_VERIFYPEER, 0L);
+        curl_easy_setopt(curl, CURLOPT_SSL_VERIFYHOST, 0L);
+        curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION,
+                         curl_callback_token_request);
+        curl_easy_setopt(curl, CURLOPT_WRITEDATA, &token_info);
+        curl_easy_setopt(curl, CURLOPT_USERPWD,
+                         "2b50f1123b424d5e9c21971a110fdd04:"
+                         "MrMkhVMNdOeqPL4Q4XVQAsRPR14J7Yq6");
+        curl_easy_setopt(curl, CURLOPT_POSTFIELDS,
+                         "grant_type=client_credentials");
+        CURLcode result_code;
+        result_code = curl_easy_perform(curl);
+        curl_easy_cleanup(curl);
+        if (result_code != CURLE_OK) {
+            std::cerr << "ERROR: token request failed" << std::endl;
+            std::exit(EXIT_FAILURE);
+        }
+    }
+    std::string token =
+        extract_string_with_regex(token_info, "\"access_token\":\"(\\w+)\"");
+    std::chrono::hours expires_at = get_current_time() + std::chrono::hours(24);
+    token_file << token << " " << expires_at.count();
+}
+
+void HearthstoneAPIHandler::refresh_token_if_needed() {
+    std::string file_path =
+        std::format("{}/resources/token_info.txt", SOURCE_DIR_PATH);
+    std::ifstream token_file(file_path);
+    std::string line;
+    std::getline(token_file, line);
+    if (line.empty()) {
+        write_new_token_info_to_file(file_path);
+    } else {
+        unsigned long expire_at = std::stoull(line.substr(line.find(" ") + 1));
+        if (std::chrono::duration_cast<std::chrono::hours>(
+                std::chrono::utc_clock::now().time_since_epoch())
+                .count() >= expire_at) {
+            write_new_token_info_to_file(file_path);
+        }
+    }
+}
+std::string HearthstoneAPIHandler::get_valid_token() {
+    refresh_token_if_needed();
+    std::string file_path =
+        std::format("{}/resources/token_info.txt", SOURCE_DIR_PATH);
+    std::ifstream token_file(file_path);
+    std::string line;
+    std::getline(token_file, line);
+    std::string token = line.substr(0, line.find(" "));
+    return token;
+}
+
+std::string HearthstoneAPIHandler::generate_request_header() {
+    return std::format("Authorization: Bearer {}", m_access_token);
+}
+
+const std::string
+HearthstoneAPIHandler::get_url(const std::string &t_parameters) {
+    return std::format("https://eu.api.blizzard.com/hearthstone/{}",
+                       t_parameters);
+}
+
+const std::string HearthstoneAPIHandler::get_set_of_cards_url(
+    const std::string &t_card_parameters) {
+    return get_url(std::format("cards/{}", t_card_parameters));
+}
+
+void HearthstoneAPIHandler::make_api_request(const char *t_url,
+                                             const char *t_header) {
+    CURL *curl = curl_easy_init();
+    if (curl) {
+        curl_easy_setopt(curl, CURLOPT_URL, t_url);
+        curl_easy_setopt(curl, CURLOPT_SSL_VERIFYPEER, 0L);
+        curl_easy_setopt(curl, CURLOPT_SSL_VERIFYHOST, 0L);
+        struct curl_slist *chunk = nullptr;
+        chunk = curl_slist_append(chunk, t_header);
+        curl_easy_setopt(curl, CURLOPT_HTTPHEADER, chunk);
+        curl_easy_perform(curl);
+        curl_easy_cleanup(curl);
+    }
+}
+
+void HearthstoneAPIHandler::make_api_request(const std::string &t_url,
+                                             const std::string &t_header) {
+    make_api_request(t_url.c_str(), t_header.c_str());
+}
+
+void HearthstoneAPIHandler::get_cards(const std::string &t_card_parameters) {
+    make_api_request(get_set_of_cards_url(t_card_parameters), m_header);
+}