source/ps/TemplateLoader.h

   1 /* Copyright (C) 2022 Wildfire Games.
   2  * This file is part of 0 A.D.
   3  *
   4  * 0 A.D. is free software: you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation, either version 2 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * 0 A.D. is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with 0 A.D.  If not, see <http://www.gnu.org/licenses/>.
  16  */
  17
  18 #ifndef INCLUDED_TEMPLATELOADER
  19 #define INCLUDED_TEMPLATELOADER
  20
  21 #include "simulation2/system/ParamNode.h"
  22
  23 #include <string_view>
  24 #include <unordered_map>
  25
  26 enum ETemplatesType
  27 {
  28         ALL_TEMPLATES,
  29         ACTOR_TEMPLATES,
  30         SIMULATION_TEMPLATES
  31 };
  32
  33 /**
  34  * Template loader: Handles the loading of entity template files for:
  35  * - the initialisation and deserialization of entity components in the
  36  *   simulation (CmpTemplateManager).
  37  * - access to actor templates, obstruction data, etc. in RMS/RMGEN
  38  * - access to various templates in the GUI, to display faction specificities
  39  *
  40  * Template names are intentionally restricted to ASCII strings for storage/serialization
  41  * efficiency (we have a lot of strings so this is significant);
  42  * they correspond to filenames so they shouldn't contain non-ASCII anyway.
  43  *
  44  *
  45  * TODO: Find a way to validate templates outside of the simulation.
  46  */
  47 class CTemplateLoader
  48 {
  49 public:
  50         CTemplateLoader()
  51         {
  52         }
  53
  54         /**
  55          * Provides the file data for requested template.
  56          */
  57         const CParamNode& GetTemplateFileData(const std::string& templateName);
  58
  59         /**
  60          * Check if the template XML file exits, without trying to load it.
  61          */
  62         bool TemplateExists(const std::string& templateName) const;
  63
  64         /**
  65          * Returns a list of strings that could be validly passed as @c templateName to LoadTemplateFile.
  66          * (This includes "actor|foo" etc names).
  67          */
  68         std::vector<std::string> FindTemplates(const std::string& path, bool includeSubdirectories, ETemplatesType templatesType) const;
  69
  70         /**
  71          * Returns a list of strings that could validly be passed as @c templateName to LoadTemplateFile.
  72          * Not ignoring any special directories.
  73          */
  74         std::vector<std::string> FindTemplatesUnrestricted(const std::string& path, bool includeSubdirectories) const;
  75
  76 private:
  77         /**
  78          * (Re)loads the given template, regardless of whether it exists already,
  79          * and saves into m_TemplateFileData. Also loads any parents that are not yet
  80          * loaded. Returns false on error.
  81          * @param templateName - XML filename to load (may be a |-separated string)
  82          * @param compositing - whether this template is an intermediary layer in a |-separated string.
  83          * @param depth - the current recursion depth.
  84          */
  85         bool LoadTemplateFile(CParamNode& node, std::string_view templateName, bool compositing, int depth);
  86
  87         /**
  88          * Constructs a standard static-decorative-object template for the given actor
  89          */
  90         void ConstructTemplateActor(std::string_view actorName, CParamNode& out);
  91
  92         /**
  93          * Map from template name (XML filename or special |-separated string) to the most recently
  94          * loaded non-broken template data. This includes files that will fail schema validation.
  95          * (Failed loads won't remove existing entries under the same name, so we behave more nicely
  96          * when hotloading broken files)
  97          */
  98         std::unordered_map<std::string, CParamNode> m_TemplateFileData;
  99 };
 100
 101 #endif // INCLUDED_TEMPLATELOADER