bsnes-libretro/nall/config.hpp

#pragma once

#include <nall/platform.hpp>
#include <nall/file.hpp>
#include <nall/string.hpp>

namespace nall {
namespace Configuration {

struct Node {
  string name;
  string desc;
  enum class Type : uint { Null, Boolean, Integer, Natural, Double, String } type = Type::Null;
  void* data = nullptr;
  vector<Node> children;

  explicit operator bool() const { return data; }

  auto get() const -> string {
    switch(type) {
    case Type::Boolean: return {*(bool*)data};
    case Type::Integer: return {*(int*)data};
    case Type::Natural: return {*(uint*)data};
    case Type::Double: return {*(double*)data};
    case Type::String: return {*(string*)data};
    }
    return "";
  }

  auto set(const string& value) -> void {
    switch(type) {
    case Type::Boolean: *(bool*)data = (value != "false"); break;
    case Type::Integer: *(int*)data = toInteger(value); break;
    case Type::Natural: *(uint*)data = toNatural(value); break;
    case Type::Double: *(double*)data = toReal(value); break;
    case Type::String: *(string*)data = value; break;
    }
  }

  auto assign() { type = Type::Null; data = nullptr; }
  auto assign(bool& bind) { type = Type::Boolean; data = (void*)&bind; }
  auto assign(int& bind) { type = Type::Integer; data = (void*)&bind; }
  auto assign(uint& bind) { type = Type::Natural; data = (void*)&bind; }
  auto assign(double& bind) { type = Type::Double; data = (void*)&bind; }
  auto assign(string& bind) { type = Type::String; data = (void*)&bind; }
  auto assign(const Node& node) { operator=(node); }

  template<typename T> auto append(T& data, const string& name, const string& desc = "") -> void {
    Node node;
    node.assign(data);
    node.name = name;
    node.desc = desc;
    children.append(node);
  }

  auto find(const string& path) -> maybe<Node&> {
    auto p = path.split("/");
    auto name = p.takeLeft();
    for(auto& child : children) {
      if(child.name == name) {
        if(p.size() == 0) return child;
        return child.find(p.merge("/"));
      }
    }
    return nothing;
  }

  auto load(Markup::Node path) -> void {
    for(auto& child : children) {
      if(auto leaf = path[child.name]) {
        if(child) child.set(leaf.text());
        child.load(leaf);
      }
    }
  }

  auto save(file& fp, uint depth = 0) -> void {
    for(auto& child : children) {
      if(child.desc) {
        for(auto n : range(depth)) fp.print("  ");
        fp.print("//", child.desc, "\n");
      }
      for(auto n : range(depth)) fp.print("  ");
      fp.print(child.name);
      if(child) fp.print(": ", child.get());
      fp.print("\n");
      child.save(fp, depth + 1);
      if(depth == 0) fp.print("\n");
    }
  }
};

struct Document : Node {
  auto load(const string& filename) -> bool {
    if(!file::exists(filename)) return false;
    auto document = BML::unserialize(string::read(filename));
    Node::load(document);
    return true;
  }

  auto save(const string& filename) -> bool {
    file fp(filename, file::mode::write);
    if(!fp.open()) return false;
    Node::save(fp);
    return true;
  }
};

}
}