/* Copyright (C) 2001-2019 Artifex Software, Inc.
   All Rights Reserved.

   This software is provided AS-IS with no warranty, either express or
   implied.

   This software is distributed under license and may not be copied,
   modified or distributed except as expressly authorized under the terms
   of the license contained in the file LICENSE in this distribution.

   Refer to licensing information at http://www.artifex.com or contact
   Artifex Software, Inc.,  1305 Grant Avenue - Suite 200, Novato,
   CA 94945, U.S.A., +1(415)492-9861, for further information.
*/


/* Composite font creation operator */
#include "ghost.h"
#include "oper.h"
#include "gsstruct.h"
/*
 * The following lines used to say:
 *      #include "gsmatrix.h"
 *      #include "gxdevice.h"           /. for gxfont.h ./
 * Tony Li says the longer list is necessary to keep the GNU compiler
 * happy, but this is pretty hard to understand....
 */
#include "gxfixed.h"
#include "gxmatrix.h"
#include "gzstate.h"		/* must precede gxdevice */
#include "gxdevice.h"		/* must precede gxfont */
#include "gxfcmap.h"
#include "gxfont.h"
#include "gxfont0.h"
#include "bfont.h"
#include "ialloc.h"
#include "iddict.h"
#include "idparam.h"
#include "igstate.h"
#include "iname.h"
#include "store.h"

/* Imported from zfcmap.c */
int ztype0_get_cmap(const gs_cmap_t ** ppcmap, const ref * pfdepvector,
                    const ref * op, gs_memory_t *imem);

/* Forward references */
static font_proc_define_font(ztype0_define_font);
static font_proc_make_font(ztype0_make_font);
static int ensure_char_entry(i_ctx_t *, os_ptr, const char *, byte *, int);

/* <string|name> <font_dict> .buildfont0 <string|name> <font> */
/* Build a type 0 (composite) font. */
static int
zbuildfont0(i_ctx_t *i_ctx_p)
{
    os_ptr op = osp;
    gs_type0_data data;
    ref fdepvector;
    ref *pprefenc;
    gs_font_type0 *pfont;
    font_data *pdata;
    ref save_FID;
    int i;
    int code = 0;

    check_type(*op, t_dictionary);
    {
        ref *pfmaptype;
        ref *pfdepvector;

        if (dict_find_string(op, "FMapType", &pfmaptype) <= 0 ||
            !r_has_type(pfmaptype, t_integer) ||
            pfmaptype->value.intval < (int)fmap_type_min ||
            pfmaptype->value.intval > (int)fmap_type_max ||
            dict_find_string(op, "FDepVector", &pfdepvector) <= 0 ||
            !r_is_array(pfdepvector)
            )
            return_error(gs_error_invalidfont);
        data.FMapType = (fmap_type) pfmaptype->value.intval;
        /*
         * Adding elements below could cause the font dictionary to be
         * resized, which would invalidate pfdepvector.
         */
        fdepvector = *pfdepvector;
    }
    /* Check that every element of the FDepVector is a font. */
    data.fdep_size = r_size(&fdepvector);
    for (i = 0; i < data.fdep_size; i++) {
        ref fdep;
        gs_font *psub;

        array_get(imemory, &fdepvector, i, &fdep);
        if ((code = font_param(&fdep, &psub)) < 0)
            return code;
        /*
         * Check the inheritance rules.  Allowed configurations
         * (paths from root font) are defined by the regular
         * expression:
         *      (shift | double_escape escape* | escape*)
         *        non_modal* non_composite
         */
        if (psub->FontType == ft_composite) {
            const gs_font_type0 *const psub0 = (const gs_font_type0 *)psub;
            fmap_type fmt = psub0->data.FMapType;

            if (fmt == fmap_double_escape ||
                fmt == fmap_shift ||
                (fmt == fmap_escape &&
                 !(data.FMapType == fmap_escape ||
                   data.FMapType == fmap_double_escape))
                )
                return_error(gs_error_invalidfont);
        }
    }
    switch (data.FMapType) {
        case fmap_escape:
        case fmap_double_escape:	/* need EscChar */
            code = ensure_char_entry(i_ctx_p, op, "EscChar", &data.EscChar, 255);
            break;
        case fmap_shift:	/* need ShiftIn & ShiftOut */
            code = ensure_char_entry(i_ctx_p, op, "ShiftIn", &data.ShiftIn, 15);
            if (code >= 0)
                code = ensure_char_entry(i_ctx_p, op, "ShiftOut", &data.ShiftOut, 14);
            break;
        case fmap_SubsVector:	/* need SubsVector */
            {
                ref *psubsvector;
                uint svsize;

                if (dict_find_string(op, "SubsVector", &psubsvector) <= 0 ||
                    !r_has_type(psubsvector, t_string) ||
                    (svsize = r_size(psubsvector)) == 0 ||
                (data.subs_width = (int)*psubsvector->value.bytes + 1) > 4 ||
                    (svsize - 1) % data.subs_width != 0
                    )
                    return_error(gs_error_invalidfont);
                data.subs_size = (svsize - 1) / data.subs_width;
                data.SubsVector.data = psubsvector->value.bytes + 1;
                data.SubsVector.size = svsize - 1;
            } break;
        case fmap_CMap:	/* need CMap */
            code = ztype0_get_cmap(&data.CMap, (const ref *)&fdepvector,
                                   (const ref *)op, imemory);
            break;
        default:
            ;
    }
    if (code < 0)
        return code;
    /*
     * Save the old FID in case we have to back out.
     * build_gs_font will return an error if there is a FID entry
     * but it doesn't reference a valid font.
     */
    {
        ref *pfid;

        if (dict_find_string(op, "FID", &pfid) <= 0)
            make_null(&save_FID);
        else
            save_FID = *pfid;
    }
    {
        build_proc_refs build;

        code = build_proc_name_refs(imemory, &build,
                                    "%Type0BuildChar", "%Type0BuildGlyph");
        if (code < 0)
            return code;
        code = build_gs_font(i_ctx_p, op, (gs_font **) & pfont,
                             ft_composite, &st_gs_font_type0, &build,
                             bf_options_none);
    }
    if (code != 0)
        return code;
    /* Fill in the rest of the basic font data. */
    pfont->procs.init_fstack = gs_type0_init_fstack;
    pfont->procs.define_font = ztype0_define_font;
    pfont->procs.make_font = ztype0_make_font;
    pfont->procs.next_char_glyph = gs_type0_next_char_glyph;
    pfont->procs.decode_glyph = gs_font_map_glyph_to_unicode; /* PDF needs. */
    if (dict_find_string(op, "PrefEnc", &pprefenc) <= 0) {
        ref nul;

        make_null_new(&nul);
        if ((code = idict_put_string(op, "PrefEnc", &nul)) < 0)
            goto fail;
    }
    get_GlyphNames2Unicode(i_ctx_p, (gs_font *)pfont, op);
    /* Fill in the font data */
    pdata = pfont_data(pfont);
    data.encoding_size = r_size(&pdata->Encoding);
    /*
     * Adobe interpreters apparently require that Encoding.size >= subs_size
     * +1 (not sure whether the +1 only applies if the sum of the range
     * sizes is less than the size of the code space).  The gs library
     * doesn't require this -- it only gives an error if a show operation
     * actually would reference beyond the end of the Encoding -- so we
     * check this here rather than in the library.
     */
    if (data.FMapType == fmap_SubsVector) {
        if (data.subs_size >= r_size(&pdata->Encoding)) {
            code = gs_note_error(gs_error_rangecheck);
            goto fail;
        }
    }
    data.Encoding =
        (uint *) ialloc_byte_array(data.encoding_size, sizeof(uint),
                                   "buildfont0(Encoding)");
    if (data.Encoding == 0) {
        code = gs_note_error(gs_error_VMerror);
        goto fail;
    }
    /* Fill in the encoding vector, checking to make sure that */
    /* each element is an integer between 0 and fdep_size-1. */
    for (i = 0; i < data.encoding_size; i++) {
        ref enc;

        array_get(imemory, &pdata->Encoding, i, &enc);
        if (!r_has_type(&enc, t_integer)) {
            code = gs_note_error(gs_error_typecheck);
            goto fail;
        }
        if ((ulong) enc.value.intval >= data.fdep_size) {
            code = gs_note_error(gs_error_rangecheck);
            goto fail;
        }
        data.Encoding[i] = (uint) enc.value.intval;
    }
    data.FDepVector =
        ialloc_struct_array(data.fdep_size, gs_font *,
                            &st_gs_font_ptr_element,
                            "buildfont0(FDepVector)");
    if (data.FDepVector == 0) {
        code = gs_note_error(gs_error_VMerror);
        goto fail;
    }
    for (i = 0; i < data.fdep_size; i++) {
        ref fdep;
        ref *pfid;

        array_get(pfont->memory, &fdepvector, i, &fdep);
        /* The lookup can't fail, because of the pre-check above. */
        dict_find_string(&fdep, "FID", &pfid);
        if (!r_has_type(pfid, t_fontID))
            return gs_note_error(gs_error_typecheck);

        data.FDepVector[i] = r_ptr(pfid, gs_font);
    }
    pfont->data = data;
    code = define_gs_font(i_ctx_p, (gs_font *) pfont);
    if (code >= 0)
        return code;
fail:
        /*
         * Undo the insertion of the FID entry in the dictionary.  Note that
         * some allocations (Encoding, FDepVector) are not undone.
         */
    if (r_has_type(&save_FID, t_null)) {
        ref rnfid;

        name_enter_string(pfont->memory, "FID", &rnfid);
        idict_undef(op, &rnfid);
    } else
        idict_put_string(op, "FID", &save_FID);
    gs_free_object(pfont->memory, pfont, "buildfont0(font)");
    return code;
}
/* If a newly defined or scaled composite font had to scale */
/* any composite sub-fonts, adjust the parent font's FDepVector. */
/* This is called only if gs_type0_define/make_font */
/* actually changed the FDepVector. */
static int
ztype0_adjust_FDepVector(gs_font_type0 * pfont)
{
    gs_memory_t *mem = pfont->memory;
    /* HACK: We know the font was allocated by the interpreter. */
    gs_ref_memory_t *imem = (gs_ref_memory_t *)mem;
    gs_font **pdep = pfont->data.FDepVector;
    ref newdep;
    uint fdep_size = pfont->data.fdep_size;
    ref *prdep;
    uint i;
    int code = gs_alloc_ref_array(imem, &newdep, a_readonly, fdep_size,
                                  "ztype0_adjust_matrix");

    if (code < 0)
        return code;
    for (prdep = newdep.value.refs, i = 0; i < fdep_size; i++, prdep++) {
        const ref *pdict = pfont_dict(pdep[i]);

        ref_assign(prdep, pdict);
        r_set_attrs(prdep, imemory_new_mask(imem));
    }
    /*
     * The FDepVector is an existing key in the parent's dictionary,
     * so it's safe to pass NULL as the dstack pointer to dict_put_string.
     */
    return dict_put_string(pfont_dict(pfont), "FDepVector", &newdep, NULL);
}
static int
ztype0_define_font(gs_font_dir * pdir, gs_font * pfont)
{
    gs_font_type0 *const pfont0 = (gs_font_type0 *)pfont;
    gs_font **pdep = pfont0->data.FDepVector;
    int code = gs_type0_define_font(pdir, pfont);

    if (code < 0 || pfont0->data.FDepVector == pdep)
        return code;
    return ztype0_adjust_FDepVector(pfont0);
}
static int
ztype0_make_font(gs_font_dir * pdir, const gs_font * pfont,
                 const gs_matrix * pmat, gs_font ** ppfont)
{
    gs_font_type0 **const ppfont0 = (gs_font_type0 **)ppfont;
    gs_font **pdep = (*ppfont0)->data.FDepVector;
    int code;

    code = zdefault_make_font(pdir, pfont, pmat, ppfont);
    if (code < 0)
        return code;
    code = gs_type0_make_font(pdir, pfont, pmat, ppfont);
    if (code < 0)
        return code;
    if ((*ppfont0)->data.FDepVector == pdep)
        return 0;
    return ztype0_adjust_FDepVector(*ppfont0);
}

/* ------ Internal routines ------ */

/* Find or add a character entry in a font dictionary. */
static int
ensure_char_entry(i_ctx_t *i_ctx_p, os_ptr op, const char *kstr,
                  byte * pvalue, int default_value)
{
    ref *pentry;

    if (dict_find_string(op, kstr, &pentry) <= 0) {
        ref ent;

        make_int(&ent, default_value);
        *pvalue = (byte) default_value;
        return idict_put_string(op, kstr, &ent);
    } else {
        check_int_leu_only(*pentry, 255);
        *pvalue = (byte) pentry->value.intval;
        return 0;
    }
}

/* ------ Initialization procedure ------ */

const op_def zfont0_op_defs[] =
{
    {"2.buildfont0", zbuildfont0},
    op_def_end(0)
};
