// -*- C++ -*-
/**
 * \file Buffer.h
 * This file is part of LyX, the document processor.
 * Licence details can be found in the file COPYING.
 *
 * \author Lars Gullik Bjønnes
 *
 * Full author contact details are available in file CREDITS.
 */

#ifndef BUFFER_H
#define BUFFER_H

#include "OutputEnums.h"
#include "OutputParams.h"

#include "insets/InsetCode.h"

#include "support/strfwd.h"
#include "support/types.h"

#include <map>
#include <list>
#include <set>
#include <string>
#include <vector>


namespace lyx {

class BiblioInfo;
class BibTeXInfo;
class BufferParams;
class DispatchResult;
class DocIterator;
class docstring_list;
class ErrorList;
class FuncRequest;
class FuncStatus;
class Inset;
class InsetLabel;
class InsetRef;
class Font;
class Format;
class Lexer;
class Text;
class LyXVC;
class LaTeXFeatures;
class Language;
class MacroData;
class MacroNameSet;
class MacroSet;
class OutputParams;
class Paragraph;
class ParConstIterator;
class ParIterator;
class ParagraphList;
class TeXErrors;
class TexRow;
class TocBackend;
class Undo;
class WordLangTuple;

namespace frontend {
class GuiBufferDelegate;
class WorkAreaManager;
}

namespace support {
class FileName;
class FileNameList;
}

namespace graphics {
class PreviewLoader;
}


class Buffer;
typedef std::list<Buffer *> ListOfBuffers;


/** The buffer object.
 * This is the buffer object. It contains all the informations about
 * a document loaded into LyX.
 * The buffer object owns the Text (wrapped in an InsetText), which
 * contains the individual paragraphs of the document.
 *
 *
 * I am not sure if the class is complete or
 * minimal, probably not.
 * \author Lars Gullik Bjønnes
 */
class Buffer {
public:
	/// What type of log will \c getLogName() return?
	enum LogType {
		latexlog, ///< LaTeX log
		buildlog  ///< Literate build log
	};

	/// Result of \c readFile()
	enum ReadStatus {
		ReadSuccess,
		ReadCancel,
		// failures
		ReadFailure,
		ReadWrongVersion,
		ReadFileNotFound,
		ReadVCError,
		ReadAutosaveFailure,		
		ReadEmergencyFailure,
		ReadNoLyXFormat,
		ReadDocumentFailure,
		// lyx2lyx
		LyX2LyXNoTempFile,
		LyX2LyXNotFound,
		LyX2LyXOlderFormat,
		LyX2LyXNewerFormat,
		// other
		ReadOriginal
	};

	enum ExportStatus {
		// export
		ExportSuccess,
		ExportError,
		ExportNoPathToFormat,
		ExportTexPathHasSpaces,
		ExportConverterError,
		// preview
		PreviewSuccess,
		PreviewError
	};

	/// Method to check if a file is externally modified, used by
	/// isExternallyModified()
	/**
	 * timestamp is fast but inaccurate. For example, the granularity
	 * of timestamp on a FAT filesystem is 2 second. Also, various operations
	 * may touch the timestamp of a file even when its content is unchanged.
	 *
	 * checksum is accurate but slow, which can be a problem when it is
	 * frequently used, or used for a large file on a slow (network) file
	 * system.
	 *
	 * FIXME: replace this method with support/FileMonitor.
	 */
	enum CheckMethod {
		checksum_method, ///< Use file checksum
		timestamp_method ///< Use timestamp, and checksum if timestamp has changed
	};

	///
	enum UpdateScope {
		UpdateMaster,
		UpdateChildOnly
	};

	/// Constructor
	explicit Buffer(std::string const & file, bool readonly = false,
		Buffer const * cloned_buffer = 0);

	/// Destructor
	~Buffer();

	///
	Buffer * clone() const;
	///
	bool isClone() const;

	/** High-level interface to buffer functionality.
	    This function parses a command string and executes it.
	*/
	void dispatch(std::string const & command, DispatchResult & result);

	/// Maybe we know the function already by number...
	void dispatch(FuncRequest const & func, DispatchResult & result);

	/// Can this function be exectued?
	/// \return true if we made a decision
	bool getStatus(FuncRequest const & cmd, FuncStatus & flag);

	///
	DocIterator getParFromID(int id) const;
	/// do we have a paragraph with this id?
	bool hasParWithID(int id) const;

	///
	frontend::WorkAreaManager & workAreaManager() const;

	/** Save file.
	    Takes care of auto-save files and backup file if requested.
	    Returns \c true if the save is successful, \c false otherwise.
	*/
	bool save() const;
	/// Renames and saves the buffer
	bool saveAs(support::FileName const & fn);

	/// Write document to stream. Returns \c false if unsuccessful.
	bool write(std::ostream &) const;
	/// Write file. Returns \c false if unsuccessful.
	bool writeFile(support::FileName const &) const;

	/// \name Functions involved in reading files/strings.
	//@{
	/// Loads the LyX file into the buffer. This function
	/// tries to extract the file from version control if it
	/// cannot be found. If it can be found, it will try to
	/// read an emergency save file or an autosave file.
	/// \sa loadThisLyXFile
	ReadStatus loadLyXFile();
	/// Loads the LyX file \c fn into the buffer. If you want
	/// to check for files in a version control container,
	/// emergency or autosave files, one should use \c loadLyXFile.
	/// /sa loadLyXFile
	ReadStatus loadThisLyXFile(support::FileName const & fn);
	/// read a new document from a string
	bool readString(std::string const &);
	/// Reloads the LyX file
	ReadStatus reload();
//FIXME: The following function should be private
//private:
	/// read the header, returns number of unknown tokens
	int readHeader(Lexer & lex);

private:
	///
	typedef std::map<Buffer const *, Buffer *> BufferMap;
	///
	void clone(BufferMap &) const;
	/// save timestamp and checksum of the given file.
	void saveCheckSum() const;	
	/// read a new file
	ReadStatus readFile(support::FileName const & fn);
	/// Reads a file without header.
	/// \param par if != 0 insert the file.
	/// \return \c true if file is not completely read.
	bool readDocument(Lexer &);
	/// Try to extract the file from a version control container
	/// before reading if the file cannot be found. This is only
	/// implemented for RCS.
	/// \sa LyXVC::file_not_found_hook
	ReadStatus extractFromVC();
	/// Reads the first tag of a LyX File and 
	/// returns the file format number.
	ReadStatus parseLyXFormat(Lexer & lex, support::FileName const & fn,
		int & file_format) const;
	/// Convert the LyX file to the LYX_FORMAT using
	/// the lyx2lyx script and returns the filename
	/// of the temporary file to be read
	ReadStatus convertLyXFormat(support::FileName const & fn, 
		support::FileName & tmpfile, int from_format);
	//@}

public:
	/// \name Functions involved in autosave and emergency files.
	//@{
	/// Save an autosave file to #filename.lyx#
	bool autoSave() const;	
	/// save emergency file
	/// \return a status message towards the user.
	docstring emergencyWrite();

//FIXME:The following function should be private
//private:
	///
	void removeAutosaveFile() const;
	
private:
	/// Try to load an autosave file associated to \c fn.
	ReadStatus loadAutosave();
	/// Try to load an emergency file associated to \c fn. 
	ReadStatus loadEmergency();
	/// Get the filename of the emergency file associated with the Buffer
	support::FileName getEmergencyFileName() const;
	/// Get the filename of the autosave file associated with the Buffer
	support::FileName getAutosaveFileName() const;
	///
	void moveAutosaveFile(support::FileName const & old) const;
	//@}

public:
	/// Fill in the ErrorList with the TeXErrors
	void bufferErrors(TeXErrors const &, ErrorList &) const;

	/// Just a wrapper for writeLaTeXSource, first creating the ofstream.
	bool makeLaTeXFile(support::FileName const & filename,
			   std::string const & original_path,
			   OutputParams const &,
			   bool output_preamble = true,
			   bool output_body = true) const;
	/** Export the buffer to LaTeX.
	    If \p os is a file stream, and params().inputenc is "auto" or
	    "default", and the buffer contains text in different languages
	    with more than one encoding, then this method will change the
	    encoding associated to \p os. Therefore you must not call this
	    method with a string stream if the output is supposed to go to a
	    file. \code
	    ofdocstream ofs;
	    otexstream os(ofs, texrow);
	    ofs.open("test.tex");
	    writeLaTeXSource(os, ...);
	    ofs.close();
	    \endcode is NOT equivalent to \code
	    odocstringstream oss;
	    otexstream os(oss, texrow);
	    writeLaTeXSource(os, ...);
	    ofdocstream ofs;
	    ofs.open("test.tex");
	    ofs << oss.str();
	    ofs.close();
	    \endcode
	 */
	void writeLaTeXSource(otexstream & os,
			   std::string const & original_path,
			   OutputParams const &,
			   bool output_preamble = true,
			   bool output_body = true) const;
	///
	void makeDocBookFile(support::FileName const & filename,
			     OutputParams const & runparams_in,
			     bool only_body = false) const;
	///
	void writeDocBookSource(odocstream & os, std::string const & filename,
			     OutputParams const & runparams_in,
			     bool only_body = false) const;
	///
	void makeLyXHTMLFile(support::FileName const & filename,
			     OutputParams const & runparams_in) const;
	///
	void writeLyXHTMLSource(odocstream & os,
			     OutputParams const & runparams_in,
			     bool only_body = false) const;
	/// returns the main language for the buffer (document)
	Language const * language() const;
	/// get l10n translated to the buffers language
	docstring const B_(std::string const & l10n) const;

	///
	int runChktex();
	/// return true if the main lyx file does not need saving
	bool isClean() const;
	///
	bool isDepClean(std::string const & name) const;

	/// whether or not disk file has been externally modified
	bool isExternallyModified(CheckMethod method) const;

	/// mark the main lyx file as not needing saving
	void markClean() const;

	///
	void markDepClean(std::string const & name);

	///
	void setUnnamed(bool flag = true);

	/// Whether or not a filename has been assigned to this buffer
	bool isUnnamed() const;

	/// Whether or not this buffer is internal.
	///
	/// An internal buffer does not contain a real document, but some auxiliary text segment.
	/// It is not associated with a filename, it is never saved, thus it does not need to be
	/// automatically saved, nor it needs to trigger any "do you want to save ?" question.
	bool isInternal() const;

	/// Mark this buffer as dirty.
	void markDirty();

	/// Returns the buffer's filename. It is always an absolute path.
	support::FileName fileName() const;

	/// Returns the buffer's filename. It is always an absolute path.
	std::string absFileName() const;

	/// Returns the the path where the buffer lives.
	/// It is always an absolute path.
	std::string filePath() const;

	/** A transformed version of the file name, adequate for LaTeX.
	    \param no_path optional if \c true then the path is stripped.
	*/
	std::string latexName(bool no_path = true) const;

	/// Get the name and type of the log.
	std::string logName(LogType * type = 0) const;

	/// Set document's parent Buffer.
	void setParent(Buffer const *);
	Buffer const * parent() const;

	/** Get the document's master (or \c this if this is not a
	    child document)
	 */
	Buffer const * masterBuffer() const;

	/// \return true if \p child is a child of this \c Buffer.
	bool isChild(Buffer * child) const;
	
	/// \return true if this \c Buffer has children
	bool hasChildren() const;
	
	/// \return a list of the direct children of this Buffer.
	/// this list has no duplicates and is in the order in which
	/// the children appear.
	ListOfBuffers getChildren() const;
	
	/// \return a list of all descendents of this Buffer (children,
	/// grandchildren, etc). this list has no duplicates and is in
	/// the order in which the children appear.
	ListOfBuffers getDescendents() const;

	/// Collect all relative buffers, in the order in which they appear.
	/// I.e., the "root" Buffer is first, then its first child, then any
	/// of its children, etc. However, there are no duplicates in this
	/// list.
	/// This is "stable", too, in the sense that it returns the same
	/// thing from whichever Buffer it is called.
	ListOfBuffers allRelatives() const;

	/// Is buffer read-only?
	bool isReadonly() const;

	/// Set buffer read-only flag
	void setReadonly(bool flag = true);

	/** Validate a buffer for LaTeX.
	    This validates the buffer, and returns a struct for use by
	    #makeLaTeX# and others. Its main use is to figure out what
	    commands and packages need to be included in the LaTeX file.
	    It (should) also check that the needed constructs are there
	    (i.e. that the \refs points to coresponding \labels). It
	    should perhaps inset "error" insets to help the user correct
	    obvious mistakes.
	*/
	void validate(LaTeXFeatures &) const;

	/// Reference information is cached in the Buffer, so we do not
	/// have to check or read things over and over. 
	///
	/// There are two caches.
	///
	/// One is a cache of the BibTeX files from which reference info is
	/// being gathered. This cache is PER BUFFER, and the cache for the
	/// master essentially includes the cache for its children. This gets
	/// invalidated when an InsetBibtex is created, deleted, or modified.
	/// 
	/// The other is a cache of the reference information itself. This
	/// exists only in the master buffer, and when it needs to be updated,
	/// the children add their information to the master's cache.
	
	/// Calling this method invalidates the cache and so requires a
	/// re-read.
	void invalidateBibinfoCache() const;
	/// This invalidates the cache of files we need to check.
	void invalidateBibfileCache() const;
	/// Updates the cached bibliography information, checking first to see
	/// whether the cache is valid. If so, we do nothing. If not, then we
	/// reload all the BibTeX info.
	/// Note that this operates on the master document.
	void reloadBibInfoCache() const;
	/// \return the bibliography information for this buffer's master,
	/// or just for it, if it isn't a child.
	BiblioInfo const & masterBibInfo() const;
	/// collect bibliography info from the various insets in this buffer.
	void collectBibKeys() const;
	/// add some BiblioInfo to our cache
	void addBiblioInfo(BiblioInfo const & bi) const;
	/// add a single piece of bibliography info to our cache
	void addBibTeXInfo(docstring const & key, BibTeXInfo const & bi) const;
	///
	bool citeLabelsValid() const;
	///
	void getLabelList(std::vector<docstring> &) const;

	///
	void changeLanguage(Language const * from, Language const * to);

	///
	bool isMultiLingual() const;
	///
	std::set<Language const *> getLanguages() const;

	///
	BufferParams & params();
	BufferParams const & params() const;

	/** The list of paragraphs.
	    This is a linked list of paragraph, this list holds the
	    whole contents of the document.
	 */
	ParagraphList & paragraphs();
	ParagraphList const & paragraphs() const;

	/// LyX version control object.
	LyXVC & lyxvc();
	LyXVC const & lyxvc() const;

	/// Where to put temporary files.
	std::string const temppath() const;

	/// Used when typesetting to place errorboxes.
	TexRow const & texrow() const;
	TexRow & texrow();

	///
	ParIterator par_iterator_begin();
	///
	ParConstIterator par_iterator_begin() const;
	///
	ParIterator par_iterator_end();
	///
	ParConstIterator par_iterator_end() const;

	// Position of the child buffer where it appears first in the master.
	DocIterator firstChildPosition(Buffer const * child);

	/** \returns true only when the file is fully loaded.
	 *  Used to prevent the premature generation of previews
	 *  and by the citation inset.
	 */
	bool isFullyLoaded() const;
	/// Set by buffer_funcs' newFile.
	void setFullyLoaded(bool);

	/// FIXME: Needed by RenderPreview.
	graphics::PreviewLoader * loader() const;
	/// Update the LaTeX preview snippets associated with this buffer
	void updatePreviews() const;
	/// Remove any previewed LaTeX snippets associated with this buffer
	void removePreviews() const;

	/// Our main text (inside the top InsetText)
	Text & text() const;

	/// Our top InsetText
	Inset & inset() const;

	//
	// Macro handling
	//
	/// Collect macro definitions in paragraphs
	void updateMacros() const;
	/// Iterate through the whole buffer and try to resolve macros
	void updateMacroInstances(UpdateType) const;

	/// List macro names of this buffer, the parent and the children
	void listMacroNames(MacroNameSet & macros) const;
	/// Collect macros of the parent and its children in front of this buffer.
	void listParentMacros(MacroSet & macros, LaTeXFeatures & features) const;

	/// Return macro defined before pos (or in the master buffer)
	MacroData const * getMacro(docstring const & name, DocIterator const & pos, bool global = true) const;
	/// Return macro defined anywhere in the buffer (or in the master buffer)
	MacroData const * getMacro(docstring const & name, bool global = true) const;
	/// Return macro defined before the inclusion of the child
	MacroData const * getMacro(docstring const & name, Buffer const & child, bool global = true) const;

	/// Collect user macro names at loading time
	typedef std::set<docstring> UserMacroSet;
	mutable UserMacroSet usermacros;

	/// Replace the inset contents for insets which InsetCode is equal
	/// to the passed \p inset_code.
	void changeRefsIfUnique(docstring const & from, docstring const & to,
		InsetCode code);

	/// get source code (latex/docbook) for some paragraphs, or all paragraphs
	/// including preamble
	void getSourceCode(odocstream & os, std::string const format,
			   pit_type par_begin, pit_type par_end, bool full_source) const;

	/// Access to error list.
	/// This method is used only for GUI visualisation of Buffer related
	/// errors (like parsing or LateX compilation). This method is const
	/// because modifying the returned ErrorList does not touch the document
	/// contents.
	ErrorList & errorList(std::string const & type) const;

	/// The Toc backend.
	/// This is useful only for screen visualisation of the Buffer. This
	/// method is const because modifying this backend does not touch
	/// the document contents.
	TocBackend & tocBackend() const;

	///
	Undo & undo();

	/// This function is called when the buffer is changed.
	void changed(bool update_metrics) const;
	///
	void setChild(DocIterator const & dit, Buffer * child);
	///
	void updateTocItem(std::string const &, DocIterator const &) const;
	/// This function is called when the buffer structure is changed.
	void structureChanged() const;
	/// This function is called when some parsing error shows up.
	void errors(std::string const & err, bool from_master = false) const;
	/// This function is called when the buffer busy status change.
	void setBusy(bool on) const;
	/// Update window titles of all users.
	void updateTitles() const;
	/// Reset autosave timers for all users.
	void resetAutosaveTimers() const;
	///
	void message(docstring const & msg) const;

	///
	void setGuiDelegate(frontend::GuiBufferDelegate * gui);
	///
	bool hasGuiDelegate() const;

	///
	bool doExport(std::string const & target, bool put_in_tempdir) const;
	///
	bool preview(std::string const & format) const;

private:
	/// target is a format name optionally followed by a space
	/// and a destination file-name
	ExportStatus doExport(std::string const & target, bool put_in_tempdir,
		bool includeall, std::string & result_file) const;
	///
	ExportStatus doExport(std::string const & target, bool put_in_tempdir,
		bool includeall) const;
	///
	ExportStatus preview(std::string const & format, bool includeall = false) const;

public:
	/// mark the buffer as busy exporting something, or not
	void setExportStatus(bool e) const;
	///
	bool isExporting() const;

	///
	typedef std::vector<std::pair<Inset *, ParIterator> > References;
	References & references(docstring const & label);
	References const & references(docstring const & label) const;
	void clearReferenceCache() const;
	void setInsetLabel(docstring const & label, InsetLabel const * il);
	InsetLabel const * insetLabel(docstring const & label) const;

	/// return a list of all used branches (also in children)
	void getUsedBranches(std::list<docstring> &, bool const from_master = false) const;

	/// sets the buffer_ member for every inset in this buffer.
	// FIXME This really shouldn't be needed, but at the moment it's not
	// clear how to do it just for the individual pieces we need.
	void setBuffersForInsets() const;
	/// Updates screen labels and some other information associated with
	/// insets and paragraphs. Actually, it's more like a general "recurse
	/// through the Buffer" routine, that visits all the insets and paragraphs.
	void updateBuffer() const { updateBuffer(UpdateMaster, InternalUpdate); }
	/// \param scope: whether to start with the master document or just
	/// do this one.
	/// \param output: whether we are preparing for output.
	void updateBuffer(UpdateScope scope, UpdateType utype) const;
	/// 
	void updateBuffer(ParIterator & parit, UpdateType utype) const;

	/// Spellcheck starting from \p from.
	/// \p from initial position, will then points to the next misspelled
	///    word.
	/// \p to will points to the end of the next misspelled word.
	/// \p word_lang will contain the found misspelled word.
	/// \return progress if a new word was found.
	int spellCheck(DocIterator & from, DocIterator & to,
		WordLangTuple & word_lang, docstring_list & suggestions) const;
	///
	void checkChildBuffers();

private:
	/// Change name of buffer. Updates "read-only" flag.
	void setFileName(support::FileName const & fname);
	///
	void getLanguages(std::set<Language const *> &) const;
	/// Checks whether any of the referenced bibfiles have changed since the
	/// last time we loaded the cache. Note that this does NOT update the
	/// cached information.
	void checkIfBibInfoCacheIsValid() const;
	/// Update the list of all bibfiles in use (including bibfiles
	/// of loaded child documents).
	void updateBibfilesCache(UpdateScope scope = UpdateMaster) const;
	/// Return the list with all bibfiles in use (including bibfiles
	/// of loaded child documents).
	support::FileNameList const & 
		getBibfilesCache(UpdateScope scope = UpdateMaster) const;
	///
	void collectChildren(ListOfBuffers & children, bool grand_children) const;

	/// noncopyable
	Buffer(Buffer const &);
	void operator=(Buffer const &);

	/// Use the Pimpl idiom to hide the internals.
	class Impl;
	/// The pointer never changes although *pimpl_'s contents may.
	Impl * const d;
};


} // namespace lyx

#endif