#ifndef PGF_H_
#define PGF_H_

#include <gu/exn.h>
#include <gu/mem.h>
#include <gu/map.h>
#include <gu/enum.h>
#include <gu/string.h>


typedef GuString PgfCId;
extern GU_DECLARE_TYPE(PgfCId, typedef);

typedef GuString PgfToken;

extern GU_DECLARE_TYPE(PgfExn, abstract);
extern GU_DECLARE_TYPE(PgfParseError, abstract);
extern GU_DECLARE_TYPE(PgfTypeError, abstract);

/// @name PGF Grammar objects
/// @{

typedef struct PgfPGF PgfPGF;

typedef struct PgfConcr PgfConcr;


/**< A representation of a PGF grammar. 
 */

#include <pgf/expr.h>
#include <pgf/graphviz.h>

/// An enumeration of #PgfExpr elements.
typedef GuEnum PgfExprEnum;

PgfPGF*
pgf_read(const char* fpath,
         GuPool* pool, GuExn* err);

/**< Read a grammar from a PGF file.
 *
 * @param from  PGF input stream.
 * The stream must be positioned in the beginning of a binary
 * PGF representation. After a succesful invocation, the stream is
 * still open and positioned at the end of the representation.
 *
 * @param[out] err_out  Raised error.
 * If non-\c NULL, \c *err_out should be \c NULL. Then, upon
 * failure, \c *err_out is set to point to a newly allocated
 * error object, which the caller must free with #g_exn_free
 * or #g_exn_propagate.
 *
 * @return A new PGF object, or \c NULL upon failure. The returned
 * object must later be freed with #pgf_free.
 *
 */

GuString
pgf_abstract_name(PgfPGF*);

void
pgf_iter_languages(PgfPGF*, GuMapItor*, GuExn* err);

PgfConcr*
pgf_get_language(PgfPGF*, PgfCId lang);

GuString
pgf_concrete_name(PgfConcr*);

GuString
pgf_language_code(PgfConcr* concr);

void
pgf_iter_categories(PgfPGF* pgf, GuMapItor* fn, GuExn* err);

PgfCId
pgf_start_cat(PgfPGF* pgf);

void
pgf_iter_functions(PgfPGF* pgf, GuMapItor* fn, GuExn* err);

void
pgf_iter_functions_by_cat(PgfPGF* pgf, PgfCId catname,
                          GuMapItor* fn, GuExn* err);

PgfType*
pgf_function_type(PgfPGF* pgf, PgfCId funname);

GuString
pgf_print_name(PgfConcr*, PgfCId id);

bool
pgf_has_linearization(PgfConcr* concr, PgfCId id);

void
pgf_linearize(PgfConcr* concr, PgfExpr expr, GuOut* out, GuExn* err);

bool
pgf_parseval(PgfConcr* concr, PgfExpr expr, PgfCId cat, 
             double *precision, double *recall, double *exact);
                    
PgfExprEnum*
pgf_generate_all(PgfPGF* pgf, PgfCId cat, GuPool* pool);

PgfExprEnum*
pgf_parse(PgfConcr* concr, PgfCId cat, GuString sentence,
          GuExn* err,
          GuPool* pool, GuPool* out_pool);

typedef struct PgfMorphoCallback PgfMorphoCallback;
struct PgfMorphoCallback {
	void (*callback)(PgfMorphoCallback* self,
	                 PgfCId lemma, GuString analysis, prob_t prob,
	                 GuExn* err);
};

void
pgf_lookup_morpho(PgfConcr *concr, GuString sentence,
                  PgfMorphoCallback* callback, GuExn* err);

typedef struct PgfFullFormEntry PgfFullFormEntry;

GuEnum*
pgf_fullform_lexicon(PgfConcr *concr, GuPool* pool);

GuString
pgf_fullform_get_string(PgfFullFormEntry* entry);

void
pgf_fullform_get_analyses(PgfFullFormEntry* entry,
                          PgfMorphoCallback* callback, GuExn* err);

PgfExprEnum*
pgf_parse_with_heuristics(PgfConcr* concr, PgfCId cat, 
                          GuString sentence, double heuristics,
                          GuExn* err,
                          GuPool* pool, GuPool* out_pool);

typedef struct {
	PgfToken tok;
	PgfCId cat;
	prob_t prob;
} PgfTokenProb;

GuEnum*
pgf_complete(PgfConcr* concr, PgfCId cat, GuString string, 
             GuString prefix, GuExn* err, GuPool* pool);

/// @}

void
pgf_print(PgfPGF* pgf, GuOut* out, GuExn* err); 

void
pgf_check_expr(PgfPGF* gr, PgfExpr* pe, PgfType* ty,
               GuExn* exn, GuPool* pool);

PgfType*
pgf_infer_expr(PgfPGF* gr, PgfExpr* pe, 
               GuExn* exn, GuPool* pool);

void
pgf_check_type(PgfPGF* gr, PgfType** ty,
               GuExn* exn, GuPool* pool);

#endif // PGF_H_