/* The MIT License

   Copyright (c) 2008 Genome Research Ltd (GRL).

   Permission is hereby granted, free of charge, to any person obtaining
   a copy of this software and associated documentation files (the
   "Software"), to deal in the Software without restriction, including
   without limitation the rights to use, copy, modify, merge, publish,
   distribute, sublicense, and/or sell copies of the Software, and to
   permit persons to whom the Software is furnished to do so, subject to
   the following conditions:

   The above copyright notice and this permission notice shall be
   included in all copies or substantial portions of the Software.

   THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
   EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
   MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
   NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
   BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
   ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
   CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
   SOFTWARE.
*/

/* Contact: Heng Li <lh3@sanger.ac.uk> */

#ifndef FAIDX_H
#define FAIDX_H

/*!
  @header

  Index FASTA files and extract subsequence.

  @copyright The Wellcome Trust Sanger Institute.
 */

struct __faidx_t;
typedef struct __faidx_t faidx_t;

#ifdef __cplusplus
extern "C" {
#endif

	/*!
	  @abstract   Build index for a FASTA or razip compressed FASTA file.
	  @param  fn  FASTA file name
	  @return     0 on success; or -1 on failure
	  @discussion File "fn.fai" will be generated.
	 */
	int fai_build(const char *fn);

	/*!
	  @abstract    Distroy a faidx_t struct.
	  @param  fai  Pointer to the struct to be destroyed
	 */
	void fai_destroy(faidx_t *fai);

	/*!
	  @abstract   Load index from "fn.fai".
	  @param  fn  File name of the FASTA file
	 */
	faidx_t *fai_load(const char *fn);

	/*!
	  @abstract    Fetch the sequence in a region.
	  @param  fai  Pointer to the faidx_t struct
	  @param  reg  Region in the format "chr2:20,000-30,000"
	  @param  len  Length of the region
	  @return      Pointer to the sequence; null on failure

	  @discussion The returned sequence is allocated by malloc family
	  and should be destroyed by end users by calling free() on it.
	 */
	char *fai_fetch(const faidx_t *fai, const char *reg, int *len);

	/*!
	  @abstract	   Fetch the number of sequences. 
	  @param  fai  Pointer to the faidx_t struct
	  @return	   The number of sequences
	 */
	int faidx_fetch_nseq(const faidx_t *fai);

	/*!
	  @abstract    Fetch the sequence in a region.
	  @param  fai  Pointer to the faidx_t struct
	  @param  c_name Region name
	  @param  p_beg_i  Beginning position number (zero-based)
	  @param  p_end_i  End position number (zero-based)
	  @param  len  Length of the region
	  @return      Pointer to the sequence; null on failure

	  @discussion The returned sequence is allocated by malloc family
	  and should be destroyed by end users by calling free() on it.
	 */
	char *faidx_fetch_seq(const faidx_t *fai, char *c_name, int p_beg_i, int p_end_i, int *len);

	/*!
	  @abstract    Alternative to faidx_fetch_seq().
	  @param  fai  Pointer to the faidx_t struct
	  @param  c_name Region name
	  @param  p_beg_i  Beginning position number (zero-based)
	  @param  p_end_i  End position number (zero-based)
	  @param  out  User-supplied output buffer
	  @return      Number of bytes written; -1 on failure

	  @discussion Differences with faidx_fetch_seq(): (1) writes the
	  incoming sequence to user-supplied output buffer, (2) doesn't write
	  the terminating null byte ('\0'), (3) properly handles 0-length
	  sequences, (4) returns the number of bytes written; -1 on failure.
	 */
	int faidx_fetch_seq2(const faidx_t *fai, const char *c_name, int p_beg_i, int p_end_i, char *out);

#ifdef __cplusplus
}
#endif

#endif
