/* The MIT License

   Copyright (c) 2011  Heng Li <lh3@live.co.uk>

   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.
*/

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <zlib.h>
#include "htslib/kstring.h"
#include "htslib/kseq.h"
KSTREAM_INIT(gzFile, gzread, 16384)

#define N_TMPSTR 5
#define LINE_LEN 60

// append a CIGAR operation plus length
#define write_cigar(_c, _n, _m, _v) do { \
        if (_n == _m) { \
            _m = _m? _m<<1 : 4; \
            _c = realloc(_c, _m * sizeof(unsigned)); \
        } \
        _c[_n++] = (_v); \
    } while (0)

// a fatal error
static void fatal(const char *msg)
{
    fprintf(stderr, "E %s\n", msg);
    exit(1);
}
// remove pads
static void remove_pads(const kstring_t *src, kstring_t *dst)
{
    int i, j;
    dst->l = 0;
    kputsn(src->s, src->l, dst);
    for (i = j = 0; i < dst->l; ++i)
        if (dst->s[i] != '*') dst->s[j++] = dst->s[i];
    dst->s[j] = 0;
    dst->l = j;
}

int main(int argc, char *argv[])
{
    gzFile fp;
    kstream_t *ks;
    kstring_t s, t[N_TMPSTR];
    int dret, i, k, af_n, af_max, af_i, c, is_padded = 0, write_cns = 0, *p2u = 0;
    long m_cigar = 0, n_cigar = 0;
    unsigned *af, *cigar = 0;

    while ((c = getopt(argc, argv, "pc")) >= 0) {
        switch (c) {
            case 'p': is_padded = 1; break;
            case 'c': write_cns = 1; break;
        }
    }
    if (argc == optind) {
        fprintf(stderr, "\nUsage:   ace2sam [-pc] <in.ace>\n\n");
        fprintf(stderr, "Options: -p     output padded SAM\n");
        fprintf(stderr, "         -c     write the contig sequence in SAM\n\n");
        fprintf(stderr, "Notes: 1. Fields must appear in the following order: (CO->[BQ]->(AF)->(RD->QA))\n");
        fprintf(stderr, "       2. The order of reads in AF and in RD must be identical\n");
        fprintf(stderr, "       3. Except in BQ, words and numbers must be separated by a single SPACE or TAB\n");
        fprintf(stderr, "       4. This program writes the headerless SAM to stdout and header to stderr\n\n");
        return 1;
    }

    s.l = s.m = 0; s.s = 0;
    af_n = af_max = af_i = 0; af = 0;
    for (i = 0; i < N_TMPSTR; ++i) t[i].l = t[i].m = 0, t[i].s = 0;
    fp = strcmp(argv[1], "-")? gzopen(argv[optind], "r") : gzdopen(fileno(stdin), "r");
    ks = ks_init(fp);
    while (ks_getuntil(ks, 0, &s, &dret) >= 0) {
        if (strcmp(s.s, "CO") == 0) { // contig sequence
            kstring_t *cns;
            t[0].l = t[1].l = t[2].l = t[3].l = t[4].l = 0; // 0: name; 1: padded ctg; 2: unpadded ctg/padded read; 3: unpadded read; 4: SAM line
            af_n = af_i = 0; // reset the af array
            ks_getuntil(ks, 0, &s, &dret); kputs(s.s, &t[0]); // contig name
            ks_getuntil(ks, '\n', &s, &dret); // read the whole line
            while (ks_getuntil(ks, '\n', &s, &dret) >= 0 && s.l > 0) kputsn(s.s, s.l, &t[1]); // read the padded consensus sequence
            remove_pads(&t[1], &t[2]); // construct the unpadded sequence
            // compute the array for mapping padded positions to unpadded positions
            p2u = realloc(p2u, t[1].m * sizeof(int));
            for (i = k = 0; i < t[1].l; ++i) {
                p2u[i] = k;
                if (t[1].s[i] != '*') ++k;
            }
            // write out the SAM header and contig sequences
            fprintf(stderr, "H @SQ\tSN:%s\tLN:%llu\n", t[0].s, (unsigned long long)(t[is_padded?1:2].l)); // The SAM header line
            cns = &t[is_padded?1:2];
            fprintf(stderr, "S >%s\n", t[0].s);
            for (i = 0; i < cns->l; i += LINE_LEN) {
                fputs("S ", stderr);
                for (k = 0; k < LINE_LEN && i + k < cns->l; ++k)
                    fputc(cns->s[i + k], stderr);
                fputc('\n', stderr);
            }

#define __padded2cigar(sp) do { \
        int i, l_M = 0, l_D = 0; \
        for (i = 0; i < sp.l; ++i) { \
            if (sp.s[i] == '*') { \
                if (l_M) write_cigar(cigar, n_cigar, m_cigar, l_M<<4); \
                ++l_D; l_M = 0; \
            } else { \
                if (l_D) write_cigar(cigar, n_cigar, m_cigar, l_D<<4 | 2); \
                ++l_M; l_D = 0; \
            } \
        } \
        if (l_M) write_cigar(cigar, n_cigar, m_cigar, l_M<<4); \
        else write_cigar(cigar, n_cigar, m_cigar, l_D<<4 | 2); \
    } while (0)

            if (write_cns) { // write the consensus SAM line (dummy read)
                n_cigar = 0;
                if (is_padded) __padded2cigar(t[1]);
                else write_cigar(cigar, n_cigar, m_cigar, t[2].l<<4);
                kputsn(t[0].s, t[0].l, &t[4]); kputs("\t516\t", &t[4]); kputsn(t[0].s, t[0].l, &t[4]); kputs("\t1\t60\t", &t[4]);
                for (i = 0; i < n_cigar; ++i) {
                    kputw(cigar[i]>>4, &t[4]); kputc("MIDNSHP=X"[cigar[i]&0xf], &t[4]);
                }
                kputs("\t*\t0\t0\t", &t[4]); kputsn(t[2].s, t[2].l, &t[4]); kputs("\t*", &t[4]);
            }
        } else if (strcmp(s.s, "BQ") == 0) { // contig quality
            if (t[0].l == 0) fatal("come to 'BQ' before reading 'CO'");
            if (dret != '\n') ks_getuntil(ks, '\n', &s, &dret); // read the entire "BQ" line
            if (write_cns) t[4].s[--t[4].l] = 0; // remove the trailing "*"
            for (i = 0; i < t[2].l; ++i) { // read the consensus quality
                int q;
                if (ks_getuntil(ks, 0, &s, &dret) < 0) fprintf(stderr, "E truncated contig quality\n");
                if (s.l) {
                    q = atoi(s.s) + 33;
                    if (q > 126) q = 126;
                    if (write_cns) kputc(q, &t[4]);
                } else --i;
            }
            if (dret != '\n') ks_getuntil(ks, '\n', &s, &dret);
            ks_getuntil(ks, '\n', &s, &dret); // skip the empty line
            if (write_cns) puts(t[4].s); t[4].l = 0;
        } else if (strcmp(s.s, "AF") == 0) { // padded read position
            int reversed, neg, pos;
            if (t[0].l == 0) fatal("come to 'AF' before reading 'CO'");
            if (write_cns) {
                if (t[4].l) puts(t[4].s);
                t[4].l = 0;
            }
            ks_getuntil(ks, 0, &s, &dret); // read name
            ks_getuntil(ks, 0, &s, &dret); reversed = s.s[0] == 'C'? 1 : 0; // strand
            ks_getuntil(ks, 0, &s, &dret); pos = atoi(s.s); neg = pos < 0? 1 : 0; pos = pos < 0? -pos : pos; // position
            if (af_n == af_max) { // double the af array
                af_max = af_max? af_max<<1 : 4;
                af = realloc(af, af_max * sizeof(unsigned));
            }
            af[af_n++] = pos << 2 | neg << 1 | reversed; // keep the placement information
        } else if (strcmp(s.s, "RD") == 0) { // read sequence
            if (af_i >= af_n) fatal("more 'RD' records than 'AF'");
            t[2].l = t[3].l = t[4].l = 0;
            ks_getuntil(ks, 0, &t[4], &dret); // QNAME
            if (dret != '\n') ks_getuntil(ks, '\n', &s, &dret); // read the entire RD line
            while (ks_getuntil(ks, '\n', &s, &dret) >= 0 && s.l > 0) kputs(s.s, &t[2]); // read the read sequence
        } else if (strcmp(s.s, "QA") == 0) { // clipping
            if (af_i >= af_n) fatal("more 'QA' records than 'AF'");
            int beg, end, pos, op;
            ks_getuntil(ks, 0, &s, &dret); ks_getuntil(ks, 0, &s, &dret); // skip quality clipping
            ks_getuntil(ks, 0, &s, &dret); beg = atoi(s.s) - 1; // align clipping start
            ks_getuntil(ks, 0, &s, &dret); end = atoi(s.s); // clipping end
            if (dret != '\n') ks_getuntil(ks, '\n', &s, &dret);
            // compute 1-based POS
            pos = af[af_i]>>2; // retrieve the position information
            if (af[af_i]>>1&1) pos = -pos;
            pos += beg; // now pos is the true padded position
            // generate CIGAR
            remove_pads(&t[2], &t[3]); // backup the unpadded read sequence
            n_cigar = 0;
            if (beg) write_cigar(cigar, n_cigar, m_cigar, beg<<4|4);
            if (is_padded) {
                __padded2cigar(t[2]);
                if (beg && n_cigar > 1) cigar[1] -= beg<<4; // fix the left-hand CIGAR
                if (end < t[2].l && n_cigar) cigar[n_cigar-1] -= (t[2].l - end)<<4; // fix the right-hand CIGAR
            } else {
                // generate flattened CIGAR string
                for (i = beg, k = pos - 1; i < end; ++i, ++k)
                    t[2].s[i] = t[2].s[i] != '*'? (t[1].s[k] != '*'? 0 : 1) : (t[1].s[k] != '*'? 2 : 6);
                // generate the proper CIGAR
                for (i = beg + 1, k = 1, op = t[2].s[beg]; i < end; ++i) {
                    if (op != t[2].s[i]) {
                        write_cigar(cigar, n_cigar, m_cigar, k<<4|op);
                        op = t[2].s[i]; k = 1;
                    } else ++k;
                }
                write_cigar(cigar, n_cigar, m_cigar, k<<4|op);
                // remove unnecessary "P" and possibly merge adjacent operations
                for (i = 2; i < n_cigar; ++i) {
                    if ((cigar[i]&0xf) != 1 && (cigar[i-1]&0xf) == 6 && (cigar[i-2]&0xf) != 1) {
                        cigar[i-1] = 0;
                        if ((cigar[i]&0xf) == (cigar[i-2]&0xf)) // merge operations
                            cigar[i] += cigar[i-2], cigar[i-2] = 0;
                    }
                }
                for (i = k = 0; i < n_cigar; ++i) // squeeze out dumb operations
                    if (cigar[i]) cigar[k++] = cigar[i];
                n_cigar = k;
            }
            if (end < t[2].l) write_cigar(cigar, n_cigar, m_cigar, (t[2].l - end)<<4|4);
            // write the SAM line for the read
            kputc('\t', &t[4]); // QNAME has already been written
            kputw((af[af_i]&1)? 16 : 0, &t[4]); kputc('\t', &t[4]); // FLAG
            kputsn(t[0].s, t[0].l, &t[4]); kputc('\t', &t[4]); // RNAME
            kputw(is_padded? pos : p2u[pos-1]+1, &t[4]); // POS
            kputs("\t60\t", &t[4]); // MAPQ
            for (i = 0; i < n_cigar; ++i) { // CIGAR
                kputw(cigar[i]>>4, &t[4]); kputc("MIDNSHP=X"[cigar[i]&0xf], &t[4]);
            }
            kputs("\t*\t0\t0\t", &t[4]); // empty MRNM, MPOS and TLEN
            kputsn(t[3].s, t[3].l, &t[4]); // unpadded SEQ
            kputs("\t*", &t[4]); // QUAL
            puts(t[4].s); // print to stdout
            ++af_i;
        } else if (dret != '\n') ks_getuntil(ks, '\n', &s, &dret);
    }
    ks_destroy(ks);
    gzclose(fp);
    free(af); free(s.s); free(cigar); free(p2u);
    for (i = 0; i < N_TMPSTR; ++i) free(t[i].s);
    return 0;
}