// --------------------------------------------------------------------------------
//
// Copyright (C) 2000
// Ralf Westram
//
// Permission to use, copy, modify, distribute and sell this software
// and its documentation for any purpose is hereby granted without fee,
// provided that the above copyright notice appear in all copies and
// that both that copyright notice and this permission notice appear
// in supporting documentation.  Ralf Westram makes no
// representations about the suitability of this software for any
// purpose.  It is provided "as is" without express or implied warranty.
//
// This code is part of my library.
// You may find a more recent version at http://www.reallysoft.de/
//
// --------------------------------------------------------------------------------

#include "xml.hxx"

using namespace std;

XML_Document *the_XML_Document = 0;

static const char *entities =
"  <!ENTITY nbsp \"&#160;\">\n"
"  <!ENTITY acute \"&#180;\">\n" // Acute accent (forward)
"  <!ENTITY eacute \"&#233;\">\n" // e Acute (forward)
"  <!ENTITY apostr \"&#39;\">\n" // single quote (vertical)
"  <!ENTITY semi \"&#59;\">\n"
;

static string encodeEntities(const string& str, bool /*quotedText*/) {
    // if quotedText is true the string is encoded for usage in quotes
    // currently it makes no difference, but this might change

    string neu;
    neu.reserve(str.length()*4);


    for (string::const_iterator s = str.begin(); s != str.end(); ++s) {
        char        replace = 0;
        const char *entity  = 0;

        switch (*s) {
            case '<':  { entity = "lt"; break; }
            case '>':  { entity = "gt"; break; }
            case '&':  { entity = "amp"; break; }
            case '\'':  { entity = "apostr"; break; }
            case char(0xb4):  { entity = "acute"; break; } // acute (forward)
            case '': { entity = "eacute"; break; }
            default:   { replace = *s; }
            }

        if (replace) {
            neu.append(1, replace);
        }
        else {
            xml_assert(entity);
            neu.append(1, '&');
            neu.append(entity);
            neu.append(1, ';');
        }
    }

    return neu;
}

// ----------------------
//      XML_Attribute

XML_Attribute::XML_Attribute(const string& name_, const string& content_)
    : name(name_)
    , content(content_)
    , next(0)
{}

XML_Attribute::~XML_Attribute() {
    delete next;
}
XML_Attribute *XML_Attribute::append_to(XML_Attribute *queue) {
    if (!queue) return this;
    queue->next = append_to(queue->next);
    return queue;
}
void XML_Attribute::print(FILE *out) const {
    fprintf(out, " %s=\"%s\"", name.c_str(), encodeEntities(content, true).c_str());
    if (next) next->print(out);
}

// -----------------
//      XML_Node

XML_Node::XML_Node(bool is_tag) {
    xml_assert(the_XML_Document);

    father = the_XML_Document->LatestSon();
    the_XML_Document->set_LatestSon(this);
    indent = 0;

    if (father) {
        father->add_son(this, is_tag);
        indent = father->Indent()+1;
    }

    opened = false;
}

XML_Node::~XML_Node() {
    if (father) father->remove_son(this);
    the_XML_Document->set_LatestSon(father);
}


// ----------------
//      XML_Tag

XML_Tag::XML_Tag(const string &name_)
    : XML_Node(true)
    , name(name_)
    , son(0)
    , attribute(0)
    , state(0)
    , onExtraLine(true)
{}

XML_Tag::~XML_Tag() {
    FILE *out = the_XML_Document->Out();
    xml_assert(!son);
    close(out);

    delete attribute;
}

void XML_Tag::add_attribute(const string& name_, const string& content_) {
    XML_Attribute *newAttr = new XML_Attribute(name_, content_);
    attribute = newAttr->append_to(attribute);
}

void XML_Tag::add_attribute(const string& name_, int value) {
    char buf[30];
    sprintf(buf, "%i", value);
    add_attribute(name_, buf);
}

void XML_Tag::add_son(XML_Node *son_, bool son_is_tag) {
    if (son) throw string("Tried to add a second son! Destroy previous son first.");
    son                           = son_;
    int wanted_state              = son_is_tag ? 2 : 1;
    if (state<wanted_state) state = wanted_state;
}

void XML_Tag::remove_son(XML_Node *son_) {
    if (son != son_) throw string("Tried to remove wrong son!");
    son = 0;
}

inline void to_indent(FILE *out, int indent) { int i = indent*the_XML_Document->indentation_per_level; while (i--) fputc(' ', out); }

void XML_Tag::open(FILE *out) {
    if (father && !father->Opened()) father->open(out);
    if (onExtraLine) {
        fputc('\n', out);
        to_indent(out, Indent());
    }
    fputc('<', out); fputs(name.c_str(), out);
    if (attribute) attribute->print(out);
    fputc('>', out);
    opened = true;
}

void XML_Tag::close(FILE *out) {
    if (!opened) {
        if (!the_XML_Document->skip_empty_tags || attribute || !father) {
            if (father && !father->Opened()) father->open(out);
            if (onExtraLine) {
                fputc('\n', out);
                to_indent(out, Indent());
            }
            fputc('<', out); fputs(name.c_str(), out);
            if (attribute) attribute->print(out);
            fputs("/>", out);
        }
    }
    else {
        if (state >= 2 && onExtraLine) { fputc('\n', out); to_indent(out, Indent()); }
        fprintf(out, "</%s>", name.c_str());
    }
}

// -----------------
//      XML_Text

XML_Text::~XML_Text() {
    FILE *out = the_XML_Document->Out();
    close(out);
}

void XML_Text::add_son(XML_Node *, bool) {
    throw string("Can't add son to XML_Text-Node");
}

void XML_Text::remove_son(XML_Node * /* son_ */) {
    throw string("Can't remove son from XML_Text-Node");
}

void XML_Text::open(FILE *) {}

void XML_Text::close(FILE *out) {
    if (father && !father->Opened()) father->open(out);
    fputs(encodeEntities(content, false).c_str(), out);
}

// --------------------
//      XML_Comment

XML_Comment::~XML_Comment() {
    FILE *out = the_XML_Document->Out();
    close(out);
}

void XML_Comment::add_son(XML_Node *, bool) {
    throw string("Can't add son to XML_Comment-Node");
}

void XML_Comment::remove_son(XML_Node *) {
    throw string("Can't remove son from XML_Comment-Node");
}

void XML_Comment::open(FILE *) {}

void XML_Comment::close(FILE *out) {
    fputc('\n', out); to_indent(out, Indent());
    fputs("<!--", out);
    fputs(encodeEntities(content, false).c_str(), out);
    fputs("-->", out);
}

// ---------------------
//      XML_Document

XML_Document::XML_Document(const string& name_, const string& dtd_, FILE *out_)
    : dtd(dtd_),
      root(0),
      out(out_),
      skip_empty_tags(false),
      indentation_per_level(1)
{
    xml_assert(out);
    if (the_XML_Document) GBK_terminate("You can only have one XML_Document at a time.");
    the_XML_Document = this;
    latest_son       = 0;
    root             = new XML_Tag(name_);
    xml_assert(latest_son == root);

    fputs("<?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"no\"?>\n", out);
    fprintf(out, "<!DOCTYPE %s SYSTEM '%s' [\n%s]>\n", name_.c_str(), dtd.c_str(), entities);
}

XML_Document::~XML_Document() {
    delete root;
    xml_assert(the_XML_Document == this);
    the_XML_Document = 0;
}