Added XML parser/writer

src/coders/xml.h

@@ -0,0 +1,132 @@
+#ifndef CODERS_XML_H_
+#define CODERS_XML_H_
+
+#include <string>
+#include <memory>
+#include <vector>
+#include <unordered_map>
+
+#include "commons.h"
+
+namespace xml {
+    class Node;
+    class Attribute;
+    class Document;
+
+    typedef Attribute xmlattribute;
+    typedef std::shared_ptr<Node> xmlelement;
+    typedef std::shared_ptr<Document> xmldocument;
+    typedef std::unordered_map<std::string, xmlattribute> xmlelements_map;
+
+    class Attribute {
+        std::string name;
+        std::string text;
+    public:
+        Attribute(std::string name, std::string text);
+
+        const std::string& getName() const;
+        const std::string& getText() const;
+        int64_t asInt() const;
+        double asFloat() const;
+        bool asBool() const;
+    };
+
+    /* XML element class. Text element has tag 'text' and attribute 'text' */
+    class Node {
+        std::string tag;
+        std::unordered_map<std::string, xmlattribute> attrs;
+        std::vector<xmlelement> elements;
+    public:
+        Node(std::string tag);
+
+        /* Add sub-element */
+        void add(xmlelement element);
+        
+        /* Set attribute value. Creates attribute if does not exists */
+        void set(std::string name, std::string text);
+
+        /* Get element tag */
+        const std::string& getTag() const;
+
+        inline bool isText() const {
+            return getTag() == "#";
+        }
+
+        inline const std::string& text() const {
+            return attr("#").getText();
+        }
+
+        /* Get attribute by name
+           @param name attribute name
+           @throws std::runtime_error if element has no attribute 
+           @return xmlattribute - {name, value} */
+        const xmlattribute attr(const std::string& name) const;
+        /* Get attribute by name
+           @param name name
+           @param def default value will be returned wrapped in xmlattribute 
+           if element has no attribute 
+           @return xmlattribute - {name, value} or {name, def} if not found*/
+        const xmlattribute attr(const std::string& name, const std::string& def) const;
+
+        /* Check if element has attribute
+           @param name attribute name */
+        bool has(const std::string& name) const;
+
+        /* Get sub-element by index
+           @throws std::out_of_range if an invalid index given */
+        xmlelement sub(size_t index);
+
+        /* Get number of sub-elements */
+        size_t size() const;
+
+        const std::vector<xmlelement>& getElements() const;
+        const xmlelements_map& getAttributes() const;
+    };
+
+    class Document {
+        xmlelement root = nullptr;
+        std::string version;
+        std::string encoding;
+    public:
+        Document(std::string version, std::string encoding);
+
+        void setRoot(xmlelement element);
+        xmlelement getRoot() const;
+
+        const std::string& getVersion() const;
+        const std::string& getEncoding() const;
+    };
+
+    class Parser : public BasicParser {
+        xmldocument document;
+
+        xmlelement parseOpenTag();
+        xmlelement parseElement();
+        void parseDeclaration();
+        void parseComment();
+        std::string parseText();
+    public:
+        Parser(std::string filename, std::string source);
+
+        xmldocument parse();
+    };
+
+    /* Serialize XML Document to string 
+       @param document serializing document
+       @param nice use human readable format 
+       (with indents and line-separators)
+       @param indentStr indentation characters sequence
+       (default - 4 spaces)*/
+    extern std::string stringify(
+        const xmldocument document,
+        bool nice=true,
+        const std::string& indentStr="    "
+    );
+
+    /* Read XML Document from string
+       @param filename file name will be shown in error messages
+       @param source xml source code string */
+    extern xmldocument parse(std::string filename, std::string source);
+}
+
+#endif // CODERS_XML_H_