/* Convert DMS string to radians */

#include <ctype.h>

#include <math.h>

#include <stdlib.h>

#include <string.h>

#include "proj.h"

#include "proj_internal.h"

static double proj_strtod(char *nptr, char **endptr);

/* following should be sufficient for all but the ridiculous */

#define MAX_WORK 64

static const char *sym = "NnEeSsWw";

static const double vm[] = {DEG_TO_RAD, .0002908882086657216,

                            .0000048481368110953599};

/* byte sequence for Degree Sign U+00B0 in UTF-8. */

static constexpr char DEG_SIGN1 = '\xc2';

static constexpr char DEG_SIGN2 = '\xb0';

double dmstor(const char *is, char **rs) {

    return dmstor_ctx(pj_get_default_ctx(), is, rs);

}

double dmstor_ctx(PJ_CONTEXT *ctx, const char *is, char **rs) {

    int n, nl;

    char *s, work[MAX_WORK];

    const char *p;

    double v, tv;

    if (rs)

        *rs = (char *)is;

    /* copy string into work space */

    while (isspace(*is))

        ++is;

    n = MAX_WORK;

    s = work;

    p = (char *)is;

    /*

     * Copy characters into work until we hit a non-printable character or run

     * out of space in the buffer.  Make a special exception for the bytes of

     * the Degree Sign in UTF-8.

     *

     * It is possible that a really odd input (like lots of leading zeros)

     * could be truncated in copying into work.  But ...

     */

    while ((isgraph(static_cast<unsigned char>(*p)) || *p == DEG_SIGN1 ||

            *p == DEG_SIGN2) &&

           --n)

        *s++ = *p++;

    *s = '\0';

    int sign = *(s = work);

    if (sign == '+' || sign == '-')

        s++;

    else

        sign = '+';

    v = 0.;

    for (nl = 0; nl < 3; nl = n + 1) {

        if (!(isdigit(*s) || *s == '.'))

            break;

        if ((tv = proj_strtod(s, &s)) == HUGE_VAL)

            return tv;

        int adv = 1;

        if (*s == 'D' || *s == 'd' || *s == DEG_SIGN2) {

            /*

             * Accept \xb0 as a single-byte degree symbol. This byte is the

             * degree symbol in various single-byte encodings: multiple ISO

             * 8859 parts, several Windows code pages and others.

             */

            n = 0;

        } else if (*s == '\'') {

            n = 1;

        } else if (*s == '"') {

            n = 2;

        } else if (s[0] == DEG_SIGN1 && s[1] == DEG_SIGN2) {

            /* degree symbol in UTF-8 */

            n = 0;

            adv = 2;

        } else if (*s == 'r' || *s == 'R') {

            if (nl) {

                proj_context_errno_set(ctx,

                                       PROJ_ERR_INVALID_OP_ILLEGAL_ARG_VALUE);

                return HUGE_VAL;

            }

            ++s;

            v = tv;

            n = 4;

            continue;

        } else {

            v += tv * vm[nl];

            n = 4;

            continue;

        }

        if (n < nl) {

            proj_context_errno_set(ctx, PROJ_ERR_INVALID_OP_ILLEGAL_ARG_VALUE);

            return HUGE_VAL;

        }

        v += tv * vm[n];

        s += adv;

    }

    /* postfix sign */

    if (*s && (p = strchr(sym, *s))) {

        sign = (p - sym) >= 4 ? '-' : '+';

        ++s;

    }

    if (sign == '-')

        v = -v;

    if (rs) /* return point of next char after valid string */

        *rs = (char *)is + (s - work);

    return v;

}

static double proj_strtod(char *nptr, char **endptr)

{

    char c, *cp = nptr;

    double result;

    /*

     * Scan for characters which cause problems with VC++ strtod()

     */

    while ((c = *cp) != '\0') {

        if (c == 'd' || c == 'D') {

            /*

             * Found one, so NUL it out, call strtod(),

             * then restore it and return

             */

            *cp = '\0';

            result = strtod(nptr, endptr);

            *cp = c;

            return result;

        }

        ++cp;

    }

    /* no offending characters, just handle normally */

    return pj_strtod(nptr, endptr);

}