/*
 * Copyright (c) 2013, 2014, 2015 Genome Research Ltd.
 * Author(s): James Bonfield
 * 
 * Redistribution and use in source and binary forms, with or without 
 * modification, are permitted provided that the following conditions are met:
 * 
 *    1. Redistributions of source code must retain the above copyright notice,
 *       this list of conditions and the following disclaimer.
 * 
 *    2. Redistributions in binary form must reproduce the above
 *       copyright notice, this list of conditions and the following
 *       disclaimer in the documentation and/or other materials provided
 *       with the distribution.
 * 
 *    3. Neither the names Genome Research Ltd and Wellcome Trust Sanger
 *    Institute nor the names of its contributors may be used to endorse
 *    or promote products derived from this software without specific
 *    prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY GENOME RESEARCH LTD AND CONTRIBUTORS "AS
 * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
 * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL GENOME RESEARCH
 * LTD OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/*
 * Author: James Bonfield, Wellcome Trust Sanger Institute. 2013
 */

/*! \file
 * Include cram.h instead.
 *
 * This is an internal part of the CRAM system and is automatically included
 * when you #include cram.h.
 *
 * Implements the low level CRAM I/O primitives.
 * This includes basic data types such as byte, int, ITF-8,
 * maps, bitwise I/O, etc.
 */

#ifndef _CRAM_IO_H_
#define _CRAM_IO_H_

#ifdef __cplusplus
extern "C" {
#endif

#define ITF8_MACROS

#include <stdint.h>
#include <io_lib/misc.h>
#include <io_lib/bam.h>

/**@{ ----------------------------------------------------------------------
 * ITF8 encoding and decoding.
 *
 * Also see the itf8_get and itf8_put macros.
 */

/*! INTERNAL: Converts two characters into an integer for use in switch{} */
#define CRAM_KEY(a,b) (((a)<<8)|((b)))

/*! Reads an integer in ITF-8 encoding from 'fd' and stores it in
 * *val.
 *
 * @return
 * Returns the number of bytes read on success;
 *        -1 on failure
 */
int itf8_decode(cram_fd *fd, int32_t *val);

#ifndef ITF8_MACROS
/*! Reads an integer in ITF-8 encoding from 'cp' and stores it in
 * *val.
 *
 * @return
 * Returns the number of bytes read on success;
 *        -1 on failure
 */
int itf8_get(char *cp, int32_t *val_p);

/*! Stores a value to memory in ITF-8 format.
 *
 * @return
 * Returns the number of bytes required to store the number.
 * This is a maximum of 5 bytes.
 */
int itf8_put(char *cp, int32_t val);

#else

/*
 * Macro implementations of the above
 */
#define itf8_get(c,v) (((uc)(c)[0]<0x80)?(*(v)=(uc)(c)[0],1):(((uc)(c)[0]<0xc0)?(*(v)=(((uc)(c)[0]<<8)|(uc)(c)[1])&0x3fff,2):(((uc)(c)[0]<0xe0)?(*(v)=(((uc)(c)[0]<<16)|((uc)(c)[1]<<8)|(uc)(c)[2])&0x1fffff,3):(((uc)(c)[0]<0xf0)?(*(v)=(((uc)(c)[0]<<24)|((uc)(c)[1]<<16)|((uc)(c)[2]<<8)|(uc)(c)[3])&0x0fffffff,4):(*(v)=(((uc)(c)[0]&0x0f)<<28)|((uc)(c)[1]<<20)|((uc)(c)[2]<<12)|((uc)(c)[3]<<4)|((uc)(c)[4]&0x0f),5)))))

#define itf8_put(c,v) ((!((v)&~0x7f))?((c)[0]=(v),1):(!((v)&~0x3fff))?((c)[0]=((v)>>8)|0x80,(c)[1]=(v)&0xff,2):(!((v)&~0x1fffff))?((c)[0]=((v)>>16)|0xc0,(c)[1]=((v)>>8)&0xff,(c)[2]=(v)&0xff,3):(!((v)&~0xfffffff))?((c)[0]=((v)>>24)|0xe0,(c)[1]=((v)>>16)&0xff,(c)[2]=((v)>>8)&0xff,(c)[3]=(v)&0xff,4):((c)[0]=0xf0|(((v)>>28)&0xff),(c)[1]=((v)>>20)&0xff,(c)[2]=((v)>>12)&0xff,(c)[3]=((v)>>4)&0xff,(c)[4]=(v)&0xf,5))

#define itf8_size(v) ((!((v)&~0x7f))?1:(!((v)&~0x3fff))?2:(!((v)&~0x1fffff))?3:(!((v)&~0xfffffff))?4:5)

#endif

int ltf8_put(char *cp, int64_t val);

/* Version of itf8_get that checks it hasn't run out of input */

extern const int itf8_bytes[16];

static inline int safe_itf8_get(const char *cp, const char *endp,
				int32_t *val_p) {
  const unsigned char *up = (unsigned char *)cp;

  if (endp - cp < 5 && 
      (cp >= endp || endp - cp < itf8_bytes[up[0]>>4])) return 0;

  if (up[0] < 0x80) {
    *val_p =   up[0];
    return 1;
  } else if (up[0] < 0xc0) {
    *val_p = ((up[0] <<8) |  up[1])                           & 0x3fff;
    return 2;
  } else if (up[0] < 0xe0) {
    *val_p = ((up[0]<<16) | (up[1]<< 8) |  up[2])             & 0x1fffff;
    return 3;
  } else if (up[0] < 0xf0) {
    *val_p = ((up[0]<<24) | (up[1]<<16) | (up[2]<<8) | up[3]) & 0x0fffffff;
    return 4;
  } else {
    *val_p = ((up[0] & 0x0f)<<28) | (up[1]<<20) | (up[2]<<12) | (up[3]<<4) | (up[4] & 0x0f);
    return 5;
  }
}

/*! Pushes a value in ITF8 format onto the end of a block.
 *
 * This shouldn't be used for high-volume data as it is not the fastest
 * method.
 *
 * @return
 * Returns the number of bytes written
 */
int itf8_put_blk(cram_block *blk, int val);

/**@}*/
/**@{ ----------------------------------------------------------------------
 * CRAM blocks - the dynamically growable data block. We have code to
 * create, update, (un)compress and read/write.
 *
 * These are derived from the deflate_interlaced.c blocks, but with the
 * CRAM extension of content types and IDs.
 */

/*! Allocates a new cram_block structure with a specified content_type and
 * id.
 *
 * @return
 * Returns block pointer on success;
 *         NULL on failure
 */
cram_block *cram_new_block(enum cram_content_type content_type,
			   int content_id);

/*! Reads a block from a cram file.
 *
 * @return
 * Returns cram_block pointer on success;
 *         NULL on failure
 */
cram_block *cram_read_block(cram_fd *fd);

/*! Writes a CRAM block.
 *
 * @return
 * Returns 0 on success;
 *        -1 on failure
 */
int cram_write_block(cram_fd *fd, cram_block *b);

/*! Frees a CRAM block, deallocating internal data too.
 */
void cram_free_block(cram_block *b);

/*! Uncompresses a CRAM block, if compressed.
 *
 * @return
 * Returns 0 on success;
 *        -1 on failure
 */
int cram_uncompress_block(cram_block *b);

/*! Compresses a block.
 *
 * Compresses a block using one of two different zlib strategies. If we only
 * want one choice set strat2 to be -1.
 *
 * The logic here is that sometimes Z_RLE does a better job than Z_FILTERED
 * or Z_DEFAULT_STRATEGY on quality data. If so, we'd rather use it as it is
 * significantly faster.
 *
 * @return
 * Returns 0 on success;
 *        -1 on failure
 */
int cram_compress_block(cram_fd *fd, cram_block *b, cram_metrics *metrics,
			int method, int level);

cram_metrics *cram_new_metrics(void);
char *cram_block_method2str(enum cram_block_method m);
char *cram_content_type2str(enum cram_content_type t);

/*
 * Find an external block by its content_id
 */
static inline cram_block *cram_get_block_by_id(cram_slice *slice, int id) {
    if (slice->block_by_id && id >= 0 && id < 1024) {
        return slice->block_by_id[id];
    } else {
        int i;
        for (i = 0; i < slice->hdr->num_blocks; i++) {
            cram_block *b = slice->block[i];
            if (b && b->content_type == EXTERNAL && b->content_id == id)
                return b;
        }
    }
    return NULL;
}

/* --- Accessor macros for manipulating blocks on a byte by byte basis --- */

/* Block size and data pointer. */
#define BLOCK_SIZE(b) ((b)->byte)
#define BLOCK_DATA(b) ((b)->data)

/* Returns the address one past the end of the block */
#define BLOCK_END(b) (&(b)->data[(b)->byte])

/* Request block to be at least 'l' bytes long */
#define BLOCK_RESIZE(b,l)					\
    do {							\
	while((b)->alloc <= (l)) {				\
	    (b)->alloc = (b)->alloc ? (b)->alloc*1.5 : 1024;	\
	    (b)->data = realloc((b)->data, (b)->alloc);		\
	}							\
     } while(0)

/* Ensure the block can hold at least another 'l' bytes */
#define BLOCK_GROW(b,l) BLOCK_RESIZE((b), BLOCK_SIZE((b)) + (l))

/* Append string 's' of length 'l' */
#define BLOCK_APPEND(b,s,l)		  \
    do {				  \
        BLOCK_GROW((b),(l));		  \
        memcpy(BLOCK_END((b)), (s), (l)); \
	BLOCK_SIZE((b)) += (l);		  \
    } while (0)

/* Append as single character 'c' */
#define BLOCK_APPEND_CHAR(b,c)		  \
    do {				  \
        BLOCK_GROW((b),1);		  \
	(b)->data[(b)->byte++] = (c);	  \
    } while (0)

/* Append a single unsigned integer */
#define BLOCK_APPEND_UINT(b,i)                       \
    do {                                             \
	unsigned char *cp;                           \
	BLOCK_GROW((b),11);                          \
	cp = &(b)->data[(b)->byte];                  \
	(b)->byte += append_uint(cp, (i)) - cp;	     \
    } while (0)

#define BLOCK_UPLEN(b)			\
    (b)->comp_size = (b)->uncomp_size = BLOCK_SIZE((b))

/**@}*/
/**@{ ----------------------------------------------------------------------
 * Reference sequence handling
 */

/*! Loads a reference set from fn and stores in the cram_fd.
 *
 * @return
 * Returns 0 on success;
 *        -1 on failure
 */
int cram_load_reference(cram_fd *fd, char *fn);

/*! Generates a lookup table in refs based on the SQ headers in SAM_hdr.
 *
 * Indexes references by the order they appear in a BAM file. This may not
 * necessarily be the same order they appear in the fasta reference file.
 *
 * @return
 * Returns 0 on success;
 *        -1 on failure
 */
int refs2id(refs_t *r, SAM_hdr *bfd);

refs_t *refs_load_fai(refs_t *r_orig, char *fn, int is_err);
char *load_ref_portion(FILE *fp, ref_entry *e, int start, int end);
void refs_free(refs_t *r);

/*! Returns a portion of a reference sequence from start to end inclusive.
 *
 * The returned pointer is owned by the cram_file fd and should not be freed
 * by the caller. It is valid only until the next cram_get_ref is called
 * with the same fd parameter (so is thread-safe if given multiple files).
 *
 * To return the entire reference sequence, specify start as 1 and end
 * as 0.
 *
 * @return
 * Returns reference on success;
 *         NULL on failure
 */
char *cram_get_ref(cram_fd *fd, int id, int start, int end);
void cram_ref_incr(refs_t *r, int id);
void cram_ref_decr(refs_t *r, int id);
/**@}*/
/**@{ ----------------------------------------------------------------------
 * Containers
 */

/*! Creates a new container, specifying the maximum number of slices
 * and records permitted.
 *
 * @return
 * Returns cram_container ptr on success;
 *         NULL on failure
 */
cram_container *cram_new_container(int nrec, int nslice);
void cram_free_container(cram_container *c);

/*! Reads a container header.
 *
 * @return
 * Returns cram_container on success;
 *         NULL on failure or no container left (fd->err == 0).
 */
cram_container *cram_read_container(cram_fd *fd);

/*! Writes a container structure.
 *
 * @return
 * Returns 0 on success;
 *        -1 on failure
 */
int cram_write_container(cram_fd *fd, cram_container *h);

/*! Flushes a container to disk.
 *
 * Flushes a completely or partially full container to disk, writing
 * container structure, header and blocks. This also calls the encoder
 * functions.
 *
 * @return
 * Returns 0 on success;
 *        -1 on failure
 */
int cram_flush_container(cram_fd *fd, cram_container *c);
int cram_flush_container_mt(cram_fd *fd, cram_container *c);


/**@}*/
/**@{ ----------------------------------------------------------------------
 * Compression headers; the first part of the container
 */

/*! Creates a new blank container compression header
 *
 * @return
 * Returns header ptr on success;
 *         NULL on failure
 */
cram_block_compression_hdr *cram_new_compression_header(void);

/*! Frees a cram_block_compression_hdr */
void cram_free_compression_header(cram_block_compression_hdr *hdr);


/**@}*/
/**@{ ----------------------------------------------------------------------
 * Slices and slice headers
 */

/*! Frees a slice header */
void cram_free_slice_header(cram_block_slice_hdr *hdr);

/*! Frees a slice */
void cram_free_slice(cram_slice *s);

/*! Creates a new empty slice in memory, for subsequent writing to
 * disk.
 *
 * @return
 * Returns cram_slice ptr on success;
 *         NULL on failure
 */
cram_slice *cram_new_slice(enum cram_content_type type, int nrecs);

/*! Loads an entire slice.
 *
 * FIXME: In 1.0 the native unit of slices within CRAM is broken
 * as slices contain references to objects in other slices.
 * To work around this while keeping the slice oriented outer loop
 * we read all slices and stitch them together into a fake large
 * slice instead.
 *
 * @return
 * Returns cram_slice ptr on success;
 *         NULL on failure
 */
cram_slice *cram_read_slice(cram_fd *fd);



/**@}*/
/**@{ ----------------------------------------------------------------------
 * CRAM file definition (header)
 */

/*! Reads a CRAM file definition structure.
 *
 * @return
 * Returns file_def ptr on success;
 *         NULL on failure
 */
cram_file_def *cram_read_file_def(cram_fd *fd);

/*! Writes a cram_file_def structure to cram_fd.
 *
 * @return
 * Returns 0 on success;
 *        -1 on failure
 */
int cram_write_file_def(cram_fd *fd, cram_file_def *def);

/*! Frees a cram_file_def structure. */
void cram_free_file_def(cram_file_def *def);


/**@}*/
/**@{ ----------------------------------------------------------------------
 * SAM header I/O
 */

/*! Reads the SAM header from the first CRAM data block.
 *
 * Also performs minimal parsing to extract read-group
 * and sample information.
 *
 * @return
 * Returns SAM hdr ptr on success;
 *         NULL on failure
 */
SAM_hdr *cram_read_SAM_hdr(cram_fd *fd);

/*! Writes a CRAM SAM header.
 *
 * @return
 * Returns 0 on success;
 *        -1 on failure
 */
int cram_write_SAM_hdr(cram_fd *fd, SAM_hdr *hdr);


/**@}*/
/**@{ ----------------------------------------------------------------------
 * The top-level cram opening, closing and option handling
 */

/*! Opens a CRAM file for read (mode "rb") or write ("wb").
 *
 * The filename may be "-" to indicate stdin or stdout.
 *
 * @return
 * Returns file handle on success;
 *         NULL on failure.
 */
cram_fd *cram_open(const char *filename, const char *mode);

/*! Closes a CRAM file.
 *
 * @return
 * Returns 0 on success;
 *        -1 on failure
 */
int cram_close(cram_fd *fd);

/*
 * Flushes a CRAM file.
 * Useful for when writing to stdout without wishing to close the stream.
 *
 * Returns 0 on success
 *        -1 on failure
 */
int cram_flush(cram_fd *fd);

/*
 * Writes an EOF block to a CRAM file.
 *
 * Returns 0 on success
 *        -1 on failure
 */
int cram_write_eof_block(cram_fd *fd);

/*! Checks for end of file on a cram_fd stream.
 *
 * @return
 * Returns 0 if not at end of file
 *         1 if we hit an expected EOF (end of range or EOF block)
 *         2 for other EOF (end of stream without EOF block)
 */
int cram_eof(cram_fd *fd);

/*! Sets options on the cram_fd.
 *
 * See CRAM_OPT_* definitions in cram_structs.h.
 * Use this immediately after opening.
 *
 * @return
 * Returns 0 on success;
 *        -1 on failure
 */
int cram_set_option(cram_fd *fd, enum cram_option opt, ...);

/*! Sets options on the cram_fd.
 *
 * See CRAM_OPT_* definitions in cram_structs.h.
 * Use this immediately after opening.
 *
 * @return
 * Returns 0 on success;
 *        -1 on failure
 */
int cram_set_voption(cram_fd *fd, enum cram_option opt, va_list args);

#if defined(CRAM_IO_CUSTOM_BUFFERING)
/*
 * Opens a CRAM file for input via callbacks
 *
 * Returns file handle on success
 *         NULL on failure.
 */
extern cram_fd *cram_open_by_callbacks(
    char const * filename,
    cram_io_allocate_read_input_t   callback_allocate_function,
    cram_io_deallocate_read_input_t callback_deallocate_function,
    size_t const bufsize
);

extern cram_fd * cram_openw_by_callbacks(
    char const * filename,
    cram_io_allocate_write_output_t   callback_allocate_function,
    cram_io_deallocate_write_output_t callback_deallocate_function,
    size_t const bufsize
);

extern cram_fd * cram_io_open(
	char const * filename, 
	char const * mode, 
	char const * fmode
);
extern cram_fd * cram_io_open_by_callbacks(
    char const * filename,
    cram_io_allocate_read_input_t   callback_allocate_function,
    cram_io_deallocate_read_input_t callback_deallocate_function,
    size_t const bufsize,
    int const decompress
);

extern cram_fd * cram_io_openw_by_callbacks(
    char const * filename,
    cram_io_allocate_write_output_t   callback_allocate_function,
    cram_io_deallocate_write_output_t callback_deallocate_function,
    size_t const bufsize
);

extern cram_fd * cram_io_close(cram_fd * fd, int * fclose_result);

extern cram_fd_output_buffer *
cram_io_deallocate_output_buffer(cram_fd_output_buffer * buffer);

extern cram_fd_output_buffer *
cram_io_allocate_output_buffer(size_t const bufsize);
#endif

/**@}*/

#ifdef __cplusplus
}
#endif

#endif /* _CRAM_IO_H_ */
