refactor(client): extract config handling into a new class

src/config.cpp

@@ -0,0 +1,166 @@
+#include "config.hpp"
+
+#include <spdlog/spdlog.h>
+#include <unistd.h>
+#include <wordexp.h>
+
+#include <fstream>
+#include <stdexcept>
+
+#include "util/json.hpp"
+
+#ifndef SYSCONFDIR
+#define SYSCONFDIR "/etc"
+#endif
+
+namespace waybar {
+
+const std::string getValidPath(const std::vector<std::string> &paths) {
+  wordexp_t p;
+
+  for (const std::string &path : paths) {
+    if (wordexp(path.c_str(), &p, 0) == 0) {
+      if (access(*p.we_wordv, F_OK) == 0) {
+        std::string result = *p.we_wordv;
+        wordfree(&p);
+        return result;
+      }
+      wordfree(&p);
+    }
+  }
+
+  return std::string();
+}
+
+std::tuple<const std::string, const std::string> getConfigs(const std::string &config,
+                                                            const std::string &style) {
+  auto config_file = config.empty() ? getValidPath({
+                                          "$XDG_CONFIG_HOME/waybar/config",
+                                          "$XDG_CONFIG_HOME/waybar/config.jsonc",
+                                          "$HOME/.config/waybar/config",
+                                          "$HOME/.config/waybar/config.jsonc",
+                                          "$HOME/waybar/config",
+                                          "$HOME/waybar/config.jsonc",
+                                          "/etc/xdg/waybar/config",
+                                          "/etc/xdg/waybar/config.jsonc",
+                                          SYSCONFDIR "/xdg/waybar/config",
+                                          "./resources/config",
+                                      })
+                                    : config;
+  auto css_file = style.empty() ? getValidPath({
+                                      "$XDG_CONFIG_HOME/waybar/style.css",
+                                      "$HOME/.config/waybar/style.css",
+                                      "$HOME/waybar/style.css",
+                                      "/etc/xdg/waybar/style.css",
+                                      SYSCONFDIR "/xdg/waybar/style.css",
+                                      "./resources/style.css",
+                                  })
+                                : style;
+  if (css_file.empty() || config_file.empty()) {
+    throw std::runtime_error("Missing required resources files");
+  }
+  spdlog::info("Resources files: {}, {}", config_file, css_file);
+  return {config_file, css_file};
+}
+
+void Config::setupConfig(const std::string &config_file, int depth) {
+  if (depth > 100) {
+    throw std::runtime_error("Aborting due to likely recursive include in config files");
+  }
+  std::ifstream file(config_file);
+  if (!file.is_open()) {
+    throw std::runtime_error("Can't open config file");
+  }
+  std::string      str((std::istreambuf_iterator<char>(file)), std::istreambuf_iterator<char>());
+  util::JsonParser parser;
+  Json::Value      tmp_config = parser.parse(str);
+  if (tmp_config.isArray()) {
+    for (auto &config_part : tmp_config) {
+      resolveConfigIncludes(config_part, depth);
+    }
+  } else {
+    resolveConfigIncludes(tmp_config, depth);
+  }
+  mergeConfig(config_, tmp_config);
+}
+
+void Config::resolveConfigIncludes(Json::Value &config, int depth) {
+  Json::Value includes = config["include"];
+  if (includes.isArray()) {
+    for (const auto &include : includes) {
+      spdlog::info("Including resource file: {}", include.asString());
+      setupConfig(getValidPath({include.asString()}), ++depth);
+    }
+  } else if (includes.isString()) {
+    spdlog::info("Including resource file: {}", includes.asString());
+    setupConfig(getValidPath({includes.asString()}), ++depth);
+  }
+}
+
+void Config::mergeConfig(Json::Value &a_config_, Json::Value &b_config_) {
+  if (!a_config_) {
+    // For the first config
+    a_config_ = b_config_;
+  } else if (a_config_.isObject() && b_config_.isObject()) {
+    for (const auto &key : b_config_.getMemberNames()) {
+      if (a_config_[key].isObject() && b_config_[key].isObject()) {
+        mergeConfig(a_config_[key], b_config_[key]);
+      } else {
+        a_config_[key] = b_config_[key];
+      }
+    }
+  } else if (a_config_.isArray() && b_config_.isArray()) {
+    // This can happen only on the top-level array of a multi-bar config
+    for (Json::Value::ArrayIndex i = 0; i < b_config_.size(); i++) {
+      if (a_config_[i].isObject() && b_config_[i].isObject()) {
+        mergeConfig(a_config_[i], b_config_[i]);
+      }
+    }
+  } else {
+    spdlog::error("Cannot merge config, conflicting or invalid JSON types");
+  }
+}
+bool isValidOutput(const Json::Value &config, const std::string &name,
+                   const std::string &identifier) {
+  if (config["output"].isArray()) {
+    for (auto const &output_conf : config["output"]) {
+      if (output_conf.isString() &&
+          (output_conf.asString() == name || output_conf.asString() == identifier)) {
+        return true;
+      }
+    }
+    return false;
+  } else if (config["output"].isString()) {
+    auto config_output = config["output"].asString();
+    if (!config_output.empty()) {
+      if (config_output.substr(0, 1) == "!") {
+        return config_output.substr(1) != name && config_output.substr(1) != identifier;
+      }
+      return config_output == name || config_output == identifier;
+    }
+  }
+
+  return true;
+}
+
+void Config::load(const std::string &config, const std::string &style) {
+  std::tie(config_file_, css_file_) = getConfigs(config, style);
+  setupConfig(config_file_, 0);
+}
+
+std::vector<Json::Value> Config::getOutputConfigs(const std::string &name,
+                                                  const std::string &identifier) {
+  std::vector<Json::Value> configs;
+  if (config_.isArray()) {
+    for (auto const &config : config_) {
+      if (config.isObject() && isValidOutput(config, name, identifier)) {
+        configs.push_back(config);
+      }
+    }
+  } else if (isValidOutput(config_, name, identifier)) {
+    configs.push_back(config_);
+  }
+  return configs;
+}
+
+}  // namespace waybar