From 81351fff01e1f3d0b19d0b8007ec07d5edb16df7 Mon Sep 17 00:00:00 2001
From: "matthias@arch" <matthiasqui@protonmail.com>
Date: Thu, 29 Sep 2022 17:05:11 +0200
Subject: [PATCH] vector support for file reading

---
 src/file_io.cpp          | 22 +++++++++++++++++++---
 src/file_io.hpp          | 11 +++++++++--
 src/settings_manager.hpp |  2 +-
 3 files changed, 29 insertions(+), 6 deletions(-)

diff --git a/src/file_io.cpp b/src/file_io.cpp
index 374d90c..95621e2 100644
--- a/src/file_io.cpp
+++ b/src/file_io.cpp
@@ -28,8 +28,20 @@ namespace gz {
         return success;
     }
 
-    std::unordered_map<std::string, std::string> readKeyValueFile(const std::string& filepath, bool removeSpaces) {
-        std::unordered_map<std::string, std::string> attr;
+
+    using pairSS = std::pair<std::string, std::string>;
+    using umapSS = std::unordered_map<std::string, std::string>;
+    using mapSS = std::map<std::string, std::string>;
+    using vecSS = std::vector<pairSS>;
+
+    inline void insert(vecSS& t, pairSS&& p) { t.emplace_back(p); }
+    inline void insert(umapSS& t, pairSS&& p) { t.emplace(p); }
+    inline void insert(mapSS& t, pairSS&& p) { t.emplace(p); }
+
+
+    template<ReadKeyValueFileImplemented T>
+    T readKeyValueFile(const std::string& filepath, bool removeSpaces) {
+        T attr;
         std::string line;
         int eqPos;
         std::ifstream file(filepath);
@@ -50,7 +62,7 @@ namespace gz {
                         line.erase(std::remove_if(line.begin(), line.begin() + eqPos + 2, [](unsigned char x) { return std::isspace(x); }), line.begin() + eqPos + 2);
                     }
                     eqPos = line.find("=");
-                    attr[line.substr(0, eqPos)] = line.substr(eqPos+1, line.length());
+                    insert(attr, std::pair{ line.substr(0, eqPos), line.substr(eqPos+1, line.length()) });
                 }
             }
             file.close();
@@ -61,6 +73,10 @@ namespace gz {
         return attr;
     }
 
+    template umapSS readKeyValueFile<umapSS>(const std::string&, bool);
+    template mapSS readKeyValueFile<mapSS>(const std::string&, bool);
+    template vecSS readKeyValueFile<vecSS>(const std::string&, bool);
+
     template bool writeKeyValueFile<std::hash<std::string>, std::equal_to<std::string>>(const std::string&, const std::unordered_map<std::string, std::string, std::hash<std::string>, std::equal_to<std::string>>&);
     template bool writeKeyValueFile<util::string_hash, std::equal_to<>>(const std::string&, const std::unordered_map<std::string, std::string, util::string_hash, std::equal_to<>>&);
 }
diff --git a/src/file_io.hpp b/src/file_io.hpp
index a05c521..6c5242b 100644
--- a/src/file_io.hpp
+++ b/src/file_io.hpp
@@ -16,12 +16,19 @@ namespace gz {
     template<typename Hash, typename Pred>
     bool writeKeyValueFile(const std::string& filepath, const std::unordered_map<std::string, std::string, Hash, Pred>& content);
 
+    template<typename T>
+    concept ReadKeyValueFileImplemented = 
+        std::same_as<T, std::vector<std::pair<std::string, std::string>>> ||
+        std::same_as<T, std::map<std::string, std::string>> ||
+        std::same_as<T, std::unordered_map<std::string, std::string>> ;
+
     /**
      * @brief Read a file that contains key = value pairs
      * @throws FileIOError
      * @see @ref fio_t_key_value "Key-Value filetype"
      */
-    std::unordered_map<std::string, std::string> readKeyValueFile(const std::string& filepath, bool removeSpaces=false);
+    template<ReadKeyValueFileImplemented T>
+    T readKeyValueFile(const std::string& filepath, bool removeSpaces=false);
 }
 
 /**
@@ -33,7 +40,7 @@ namespace gz {
  * @section fio_filetypes Filetypes
  *  @subsection fio_t_key_value Simple Key-Value file
  *   A file that contains key - value pairs in each line, separated with "=".
- *   Any number of whitespaces around the separator is allowed.
+ *   Whitespaces around the separator are allowed.
  *   If the first character of a line is "#", the whole line is a comment.
  *   Example:
  *   @code
diff --git a/src/settings_manager.hpp b/src/settings_manager.hpp
index ef47feb..a18f4d5 100644
--- a/src/settings_manager.hpp
+++ b/src/settings_manager.hpp
@@ -654,7 +654,7 @@ namespace gz {
         if (filepath.empty()) {
             throw InvalidArgument("filename is not set", "readFromFile");
         }
-        std::unordered_map<std::string, std::string> map = readKeyValueFile(filepath);
+        std::unordered_map<std::string, std::string> map = readKeyValueFile<std::unordered_map<std::string, std::string>>(filepath);
         settings.insert(map.begin(), map.end());
         if (checkValidity) {
             // insert only valid values