#ifndef _HTMLPARSER_H
#define _HTMLPARSER_H

class Domain;

#include "Parser.h"
#include "extensions.h"
#include "StringMap.h"
#include "FilterGroup.h"
#include "HTMLTag.h"
#include "HTMLEntity.h"
#include "HTMLAttribute.h"

#include <iostream>
#include <vector>

using namespace std;

class HTMLParser: public Parser {
public:
	struct cssinstance {
		HTMLTag *t;
		//these are all pointers into the document
		//the strings are not copied or zero terminated
		//their start and finishes are simply remembered (8 bytes per string)
		const char *idStart;
		const char *idFinish;
		const char *classnameStart;
		const char *classnameFinish;
		const char *styleStart;
		const char *styleFinish;
	};

	//exceptions
	class BodyOverflow {};

protected:
	//---------------------------------------------------- text chunk analysis classes
	enum chunktype {
		chunk_none = 0,
		chunk_text,        //text only (bold, italic, maybe a heading as well)
		chunk_image,       //image src
		chunk_alt,         //alt details
		chunk_description, //META content
		chunk_keywords,    //META content
		chunk_title        //Page title text
	};

	//attribute combinations
	enum tagmodifier {
		noTagModifer = 0,
		metaDescription,
		metaKeywords
	};

	//a TextChunk has NO HTML markup. Just text.
	struct TextChunk {
		chunktype       m_type;           //text/image src/img alt/meta content
		const char     *m_start;          //references in source document
		const char     *m_finish;         //not zero terminated

		//statistical properties
		size_t       m_bytes;
		unsigned int m_wordCount;
		unsigned int m_alphanumerics;
		unsigned int m_grammars;
		unsigned int m_sentences;

		//structure tags
		HTMLTag *m_headingTag;            //h1 - 6 or font-br, b-br combos
		const char    *m_hrefStart;       //start finish pair: the string is not copied, just referenced in the document
		const char    *m_hrefFinish;      //not zero terminated

		//placement info
		size_t        m_markupAreaID;     //the associated continuous in-line markup area
		size_t        m_depth;            //tag depth
		vector<cssinstance> m_csspath;    //*copy* of css instances vector

		//calculated density stats
		size_t       textLength()     const {return m_finish - m_start;}
		PERCENTAGE   textDensity()    const {return m_bytes     ? textLength()    * 100  / m_bytes     : 0;}
		unsigned int wordDensity()    const {return m_bytes     ? m_wordCount     * 1000 / m_bytes     : 0;}
		PERCENTAGE   a1Density()      const {return m_bytes     ? m_alphanumerics * 100  / m_bytes     : 0;}
		PERCENTAGE   grammarDensity() const {return m_wordCount ? m_grammars      * 100  / m_wordCount : 0;}
	};

	struct selectedzone {
		size_t firstChunk;   //the index of the first TextChunk
		size_t lastChunk;    //the index of the last  TextChunk
	};

	const short m_minimumByteDensity;

	HTMLParser(const int _pagegroupid, TIPsDatabase *_db, const Domain *_domain, const int _type, short _minimumByteDensity = 50);

	//all re-entrant and thread safe as Parsers can be shared
	bool             accepts(const InternetResource *ir) const;
	char            *chunkcode(const TextChunk &tc, char *pos) const;
	const size_t     getTextChunks(const char *body, size_t bodysize, vector<TextChunk> *chunks) const;
	const size_t     calcAggregates(vector<TextChunk > *chunks, unsigned int &totalWordCount, unsigned int &totalChunksSize, unsigned int &totalAlphaNumerics, unsigned int &totalBytesSize, unsigned int &maxDepth, const HTMLTag **maxHeadingTag, unsigned int &numHeadings, PERCENTAGE &avgTextHTMLDensity, PERCENTAGE &avgAlphaNumeric, unsigned int &avgWordDensity) const;
	const size_t     generateCodeString(const vector<TextChunk> *chunks, char **rcodestring) const;
	const size_t     selectChunks(const char *codestring, Filter *f, vector<HTMLParser::selectedzone> *v) const;
	const char      *selectedzoneText(   const vector<TextChunk> *chunks, const vector<HTMLParser::selectedzone> *selectedzones) const; //caller frees result
	const char      *selectedzonesToHTML(const vector<TextChunk> *chunks, const vector<HTMLParser::selectedzone> *selectedzones, char *newbody = 0, const size_t size = 0) const; //caller frees result if newbody = 0
	const char      *debugbody(vector<TextChunk> *chunks, vector<selectedzone> *selectedzones, const char *body, const size_t bodysize) const;
};

#endif