/* <<<< Cartographic projection filter program >>>> */
#include "proj.h"
#include "proj_internal.h"
#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>
#include <string.h>
#include <math.h>
#include "emess.h"
#include "utils.h"

#include <vector>

#if defined(MSDOS) || defined(OS2) || defined(WIN32) || defined(__WIN32__)
#  include <fcntl.h>
#  include <io.h>
#  define SET_BINARY_MODE(file) _setmode(_fileno(file), O_BINARY)
#else
#  define SET_BINARY_MODE(file)
#endif

#define MAX_LINE 1000
#define MAX_PARGS 100
#define PJ_INVERSE(P) (P->inv ? 1 : 0)

static PJ *Proj;
static union {
    PJ_XY (*fwd)(PJ_LP, PJ *);
    PJ_LP (*inv)(PJ_XY, PJ *);
} proj;

static int
    reversein = 0,  /* != 0 reverse input arguments */
    reverseout = 0, /* != 0 reverse output arguments */
    bin_in = 0,     /* != 0 then binary input */
    bin_out = 0,    /* != 0 then binary output */
    echoin = 0,     /* echo input data to output line */
    tag = '#',      /* beginning of line tag character */
    inverse = 0,    /* != 0 then inverse projection */
    prescale = 0,   /* != 0 apply cartesian scale factor */
    dofactors = 0,  /* determine scale factors */
    very_verby = 0, /* very verbose mode */
    postscale = 0;

static const char
    *oform = nullptr; /* output format for x-y or decimal degrees */
static char oform_buffer[16];   /* Buffer for oform when using -d */

static const char
    *oterr = "*\t*",    /* output line for unprojectable input */
    *usage = "%s\nusage: %s [-bdeEfiIlmorsStTvVwW [args]] [+opt[=arg] ...] [file ...]\n";

static PJ_FACTORS facs;

static double (*informat)(const char *, char **), /* input data deformatter function */
              fscale = 0.;                        /* cartesian scale factor */

/* file processing function */
static void process(FILE *fid) {
    char line[MAX_LINE+3], *s = nullptr, pline[40];
    PJ_COORD data;

    for (;;) {
        int facs_bad = 0;
        ++emess_dat.File_line;

        if (bin_in) {   /* binary input */
            if (fread(&data, sizeof(PJ_UV), 1, fid) != 1)
                break;
        } else {    /* ascii input */
            if (!(s = fgets(line, MAX_LINE, fid)))
                break;

            if (!strchr(s, '\n')) { /* overlong line */
                int c;
                (void)strcat(s, "\n");
                /* gobble up to newline */
                while ((c = fgetc(fid)) != EOF && c != '\n') ;
            }

            if (*s == tag) {
                if (!bin_out)
                    (void)fputs(line, stdout);
                continue;
            }

            if (reversein) {
                data.uv.v = (*informat)(s, &s);
                data.uv.u = (*informat)(s, &s);
            } else {
                data.uv.u = (*informat)(s, &s);
                data.uv.v = (*informat)(s, &s);
            }

            if (data.uv.v == HUGE_VAL)
                data.uv.u = HUGE_VAL;

            if (!*s && (s > line)) --s; /* assumed we gobbled \n */
            if (!bin_out && echoin) {
                char t;
                t = *s;
                *s = '\0';
                (void)fputs(line, stdout);
                *s = t;
                putchar('\t');
            }
        }

        if (data.uv.u != HUGE_VAL) {
            PJ_COORD coord;
            coord.lp = data.lp;
            if (prescale) { data.uv.u *= fscale; data.uv.v *= fscale; }
            if (dofactors && !inverse) {
                facs = proj_factors(Proj, coord);
                facs_bad = proj_errno(Proj);
            }

            const auto xy = (*proj.fwd)(data.lp, Proj);
            data.xy = xy;

            if (dofactors && inverse) {
                facs = proj_factors(Proj, coord);
                facs_bad = proj_errno(Proj);
            }

            if (postscale && data.uv.u != HUGE_VAL)
                { data.uv.u *= fscale; data.uv.v *= fscale; }
        }

        if (bin_out) { /* binary output */
            (void)fwrite(&data, sizeof(PJ_UV), 1, stdout);
            continue;
        } else if (data.uv.u == HUGE_VAL) /* error output */
            (void)fputs(oterr, stdout);
        else if (inverse && !oform) {   /*ascii DMS output */
            if (reverseout) {
                (void)fputs(rtodms(pline, data.uv.v, 'N', 'S'), stdout);
                putchar('\t');
                (void)fputs(rtodms(pline, data.uv.u, 'E', 'W'), stdout);
            } else {
                (void)fputs(rtodms(pline, data.uv.u, 'E', 'W'), stdout);
                putchar('\t');
                (void)fputs(rtodms(pline, data.uv.v, 'N', 'S'), stdout);
            }
        } else {    /* x-y or decimal degree ascii output, scale if warranted by output units */
            if (inverse) {
                if (proj_angular_input(Proj, PJ_FWD)) {
                    data.uv.v *= RAD_TO_DEG;
                    data.uv.u *= RAD_TO_DEG;
                }
            } else {
                if (proj_angular_output(Proj, PJ_FWD)) {
                    data.uv.v *= RAD_TO_DEG;
                    data.uv.u *= RAD_TO_DEG;
                }
            }

            if (reverseout) {
                (void)printf(oform, data.uv.v); putchar('\t');
                (void)printf(oform, data.uv.u);
            } else {
                (void)printf(oform, data.uv.u); putchar('\t');
                (void)printf(oform, data.uv.v);
            }
        }

        /* print scale factor data */
        if (dofactors) {
            if (!facs_bad)
                (void)printf("\t<%g %g %g %g %g %g>",
                    facs.meridional_scale, facs.parallel_scale, facs.areal_scale,
                    facs.angular_distortion * RAD_TO_DEG, facs.tissot_semimajor, facs.tissot_semiminor);
            else
                (void)fputs("\t<* * * * * *>", stdout);
        }
        (void)fputs(bin_in ? "\n" : s, stdout);
        fflush(stdout);
    }
}

/* file processing function --- verbosely */
static void vprocess(FILE *fid) {
    char line[MAX_LINE+3], *s, pline[40];
    PJ_LP dat_ll;
    PJ_XY dat_xy;
    int linvers;
    PJ_COORD coord;


    if (!oform)
        oform = "%.3f";

    if (bin_in || bin_out)
        emess(1,"binary I/O not available in -V option");

    for (;;) {
        proj_errno_reset(Proj);
        ++emess_dat.File_line;

        if (!(s = fgets(line, MAX_LINE, fid)))
            break;

        if (!strchr(s, '\n')) { /* overlong line */
            int c;
            (void)strcat(s, "\n");
            /* gobble up to newline */
            while ((c = fgetc(fid)) != EOF && c != '\n') ;
        }

        if (*s == tag) { /* pass on data */
            (void)fputs(s, stdout);
            continue;
        }

        /* check to override default input mode */
        if (*s == 'I' || *s == 'i') {
            linvers = 1;
            ++s;
        } else
            linvers = inverse;

        if (linvers) {
            if (!PJ_INVERSE(Proj)) {
                emess(-1,"inverse for this projection not avail.\n");
                continue;
            }
            dat_xy.x = strtod(s, &s);
            dat_xy.y = strtod(s, &s);
            if (dat_xy.x == HUGE_VAL || dat_xy.y == HUGE_VAL) {
                emess(-1,"lon-lat input conversion failure\n");
                continue;
            }
            if (prescale) { dat_xy.x *= fscale; dat_xy.y *= fscale; }
            if (reversein) {
                PJ_XY temp = dat_xy;
                dat_xy.x = temp.y;
                dat_xy.y = temp.x;
            }
            dat_ll = pj_inv(dat_xy, Proj);
        } else {
            dat_ll.lam = proj_dmstor(s, &s);
            dat_ll.phi = proj_dmstor(s, &s);
            if (dat_ll.lam == HUGE_VAL || dat_ll.phi == HUGE_VAL) {
                emess(-1,"lon-lat input conversion failure\n");
                continue;
            }
            if (reversein) {
                PJ_LP temp = dat_ll;
                dat_ll.lam = temp.phi;
                dat_ll.phi = temp.lam;
            }
            dat_xy = pj_fwd(dat_ll, Proj);
            if (postscale) { dat_xy.x *= fscale; dat_xy.y *= fscale; }
        }

        if (proj_context_errno(nullptr)) {
            emess(-1, proj_errno_string(proj_context_errno(nullptr)));
            continue;
        }

        if (!*s && (s > line)) --s; /* assumed we gobbled \n */
        coord.lp = dat_ll;
        facs = proj_factors(Proj, coord);
        if (proj_errno(Proj)) {
            emess(-1,"failed to compute factors\n\n");
            continue;
        }

        if (*s != '\n')
            (void)fputs(s, stdout);

        (void)fputs("Longitude: ", stdout);
        (void)fputs(proj_rtodms(pline, dat_ll.lam, 'E', 'W'), stdout);
        (void)printf(" [ %.11g ]\n", dat_ll.lam * RAD_TO_DEG);
        (void)fputs("Latitude:  ", stdout);
        (void)fputs(proj_rtodms(pline, dat_ll.phi, 'N', 'S'), stdout);
        (void)printf(" [ %.11g ]\n", dat_ll.phi * RAD_TO_DEG);
        (void)fputs("Easting (x):   ", stdout);
        (void)printf(oform, dat_xy.x); putchar('\n');
        (void)fputs("Northing (y):  ", stdout);
        (void)printf(oform, dat_xy.y); putchar('\n');
        (void)printf("Meridian scale (h) : %.8f  ( %.4g %% error )\n", facs.meridional_scale, (facs.meridional_scale-1.)*100.);
        (void)printf("Parallel scale (k) : %.8f  ( %.4g %% error )\n", facs.parallel_scale, (facs.parallel_scale-1.)*100.);
        (void)printf("Areal scale (s):     %.8f  ( %.4g %% error )\n", facs.areal_scale, (facs.areal_scale-1.)*100.);
        (void)printf("Angular distortion (w): %.3f\n", facs.angular_distortion * RAD_TO_DEG);
        (void)printf("Meridian/Parallel angle: %.5f\n", facs.meridian_parallel_angle * RAD_TO_DEG);
        (void)printf("Convergence : ");
        (void)fputs(proj_rtodms(pline, facs.meridian_convergence, 0, 0), stdout);
        (void)printf(" [ %.8f ]\n", facs.meridian_convergence * RAD_TO_DEG);
        (void)printf("Max-min (Tissot axis a-b) scale error: %.5f %.5f\n\n", facs.tissot_semimajor, facs.tissot_semiminor);

        fflush(stdout);
    }
}

int main(int argc, char **argv) {
    char *arg;
    std::vector<char*> argvVector;
    char **eargv = argv;
    FILE *fid;
    int eargc = 0, mon = 0;

    if( argc == 0 ) {
        exit(1);
    }

    if ( (emess_dat.Prog_name = strrchr(*argv,DIR_CHAR)) != nullptr)
        ++emess_dat.Prog_name;
    else emess_dat.Prog_name = *argv;
    inverse = strncmp(emess_dat.Prog_name, "inv", 3) == 0 ||
              strncmp(emess_dat.Prog_name, "lt-inv", 6) == 0; // older libtool have a lt- prefix
    if (argc <= 1 ) {
        (void)fprintf(stderr, usage, pj_get_release(), emess_dat.Prog_name);
        exit (0);
    }

    /* process run line arguments */
    while (--argc > 0) { /* collect run line arguments */
        if(**++argv == '-') for(arg = *argv;;) {
            switch(*++arg) {
              case '\0': /* position of "stdin" */
                if (arg[-1] == '-') eargv[eargc++] = const_cast<char*>("-");
                break;
              case 'b': /* binary I/O */
                bin_in = bin_out = 1;
                continue;
              case 'v': /* monitor dump of initialization */
                mon = 1;
                continue;
              case 'i': /* input binary */
                bin_in = 1;
                continue;
              case 'o': /* output binary */
                bin_out = 1;
                continue;
              case 'I': /* alt. method to spec inverse */
                inverse = 1;
                continue;
              case 'E': /* echo ascii input to ascii output */
                echoin = 1;
                continue;
              case 'V': /* very verbose processing mode */
                very_verby = 1;
                mon = 1;
                continue;
              case 'S': /* compute scale factors */
                dofactors = 1;
                continue;
              case 't': /* set col. one char */
                if (arg[1]) tag = *++arg;
                else emess(1,"missing -t col. 1 tag");
                continue;
              case 'l': /* list projections, ellipses or units */
                if (!arg[1] || arg[1] == 'p' || arg[1] == 'P') {
                    /* list projections */
                    const struct PJ_LIST *lp;
                    int do_long = arg[1] == 'P', c;
                    const char *str;

                    for (lp = proj_list_operations() ; lp->id ; ++lp) {
                        if( strcmp(lp->id,"latlong") == 0
                            || strcmp(lp->id,"longlat") == 0
                            || strcmp(lp->id,"geocent") == 0 )
                            continue;

                        (void)printf("%s : ", lp->id);
                        if (do_long)  /* possibly multiline description */
                            (void)puts(*lp->descr);
                        else { /* first line, only */
                            str = *lp->descr;
                            while ((c = *str++) && c != '\n')
                                putchar(c);
                            putchar('\n');
                        }
                    }
                } else if (arg[1] == '=') { /* list projection 'descr' */
                    const struct PJ_LIST *lp;

                    arg += 2;
                    for (lp = proj_list_operations(); lp->id ; ++lp)
                        if (!strcmp(lp->id, arg)) {
                            (void)printf("%9s : %s\n", lp->id, *lp->descr);
                            break;
                        }
                } else if (arg[1] == 'e') { /* list ellipses */
                    const struct PJ_ELLPS *le;

                    for (le = proj_list_ellps(); le->id ; ++le)
                        (void)printf("%9s %-16s %-16s %s\n",
                                     le->id, le->major, le->ell, le->name);
                } else if (arg[1] == 'u') { /* list units */
                    auto units = proj_get_units_from_database(nullptr, nullptr, "linear", false, nullptr);
                    for( int i = 0; units && units[i]; i++ )
                    {
                        if( units[i]->proj_short_name )
                        {
                            (void)printf("%12s %-20.15g %s\n",
                                            units[i]->proj_short_name,
                                            units[i]->conv_factor,
                                            units[i]->name);
                        }
                    }
                    proj_unit_list_destroy(units);
                } else
                    emess(1,"invalid list option: l%c",arg[1]);
                exit(0);
                /* cppcheck-suppress duplicateBreak */
                continue; /* artificial */
              case 'e': /* error line alternative */
                if (--argc <= 0)
                    noargument:
                emess(1,"missing argument for -%c",*arg);
                oterr = *++argv;
                continue;
              case 'm': /* cartesian multiplier */
                if (--argc <= 0) goto noargument;
                postscale = 1;
                if (!strncmp("1/",*++argv,2) ||
                    !strncmp("1:",*argv,2)) {
                    if((fscale = atof((*argv)+2)) == 0.)
                        goto badscale;
                    fscale = 1. / fscale;
                } else
                    if ((fscale = atof(*argv)) == 0.) {
                      badscale:
                        emess(1,"invalid scale argument");
                    }
                continue;
              case 'W': /* specify seconds precision */
              case 'w': /* -W for constant field width */
              {
                int c = arg[1];
                if (c != 0 && isdigit(c)) {
                    set_rtodms(c - '0', *arg == 'W');
                    ++arg;
                } else
                    emess(1,"-W argument missing or non-digit");
                continue;
              }
              case 'f': /* alternate output format degrees or xy */
                if (--argc <= 0) goto noargument;
                oform = *++argv;
                continue;
              case 'd':
                if (--argc <= 0) goto noargument;
                sprintf(oform_buffer, "%%.%df", atoi(*++argv));
                oform = oform_buffer;
                break;
              case 'r': /* reverse input */
                reversein = 1;
                continue;
              case 's': /* reverse output */
                reverseout = 1;
                continue;
              default:
                emess(1, "invalid option: -%c",*arg);
                break;
            }
            break;
        } else if (**argv == '+') { /* + argument */
            argvVector.push_back(*argv + 1);
        } else /* assumed to be input file name(s) */
            eargv[eargc++] = *argv;
    }
    if (eargc == 0) /* if no specific files force sysin */
        eargv[eargc++] = const_cast<char*>("-");

    if( oform ) {
        if( !validate_form_string_for_numbers(oform) ) {
            emess(3, "invalid format string");
            exit(0);
        }
    }

    /* done with parameter and control input */
    if (inverse && postscale) {
        prescale = 1;
        postscale = 0;
        fscale = 1./fscale;
    }
    proj_context_use_proj4_init_rules(nullptr, true);

    // proj historically ignores any datum shift specifier, like nadgrids, towgs84, etc
    argvVector.push_back(const_cast<char*>("break_cs2cs_recursion"));

    if (!(Proj = proj_create_argv(nullptr, static_cast<int>(argvVector.size()), argvVector.data())))
        emess(3,"projection initialization failure\ncause: %s",
              proj_errno_string(proj_context_errno(nullptr)));

    if (!proj_angular_input(Proj, PJ_FWD)) {
        emess(3, "can't initialize operations that take non-angular input coordinates");
        exit(0);
    }

    if (proj_angular_output(Proj, PJ_FWD)) {
        emess(3, "can't initialize operations that produce angular output coordinates");
        exit(0);
    }

    // Ugly hack. See https://github.com/OSGeo/PROJ/issues/1782
    if( Proj->right == PJ_IO_UNITS_WHATEVER && Proj->descr &&
        strncmp(Proj->descr, "General Oblique Transformation",
                strlen("General Oblique Transformation")) == 0 )
    {
        Proj->right = PJ_IO_UNITS_PROJECTED;
    }

    if (inverse) {
        if (!Proj->inv)
            emess(3,"inverse projection not available");
        proj.inv = pj_inv;
    } else
        proj.fwd = pj_fwd;
    /* set input formatting control */
    if (mon) {
        pj_pr_list(Proj);
        if (very_verby) {
            (void)printf("#Final Earth figure: ");
            if (Proj->es != 0.0) {
                (void)printf("ellipsoid\n#  Major axis (a): ");
                (void)printf(oform ? oform : "%.3f", Proj->a);
                (void)printf("\n#  1/flattening: %.6f\n",
                             1./(1. - sqrt(1. - Proj->es)));
                (void)printf("#  squared eccentricity: %.12f\n", Proj->es);
            } else {
                (void)printf("sphere\n#  Radius: ");
                (void)printf(oform ? oform : "%.3f", Proj->a);
                (void)putchar('\n');
            }
        }
    }

    if (inverse)
        informat = strtod;
    else {
        informat = proj_dmstor;
        if (!oform)
            oform = "%.2f";
    }

    if (bin_out) {
        SET_BINARY_MODE(stdout);
    }

    /* process input file list */
    for ( ; eargc-- ; ++eargv) {
        if (**eargv == '-') {
            fid = stdin;
            emess_dat.File_name = const_cast<char*>("<stdin>");

            if (bin_in)
            {
                SET_BINARY_MODE(stdin);
            }

        } else {
            if ((fid = fopen(*eargv, "rb")) == nullptr) {
                emess(-2, "input file: %s", *eargv);
                continue;
            }
            emess_dat.File_name = *eargv;
        }
        emess_dat.File_line = 0;
        if (very_verby)
            vprocess(fid);
        else
            process(fid);
        (void)fclose(fid);
        emess_dat.File_name = nullptr;
    }

    if( Proj )
        proj_destroy(Proj);

    exit(0); /* normal completion */
}
