/* Copyright (C) 2020-2023 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.,  39 Mesa Street, Suite 108A, San Francisco,
   CA 94129, USA, for further information.
*/

/* pdfmark handling for the PDF interpreter */

#include "pdf_int.h"
#include "pdf_stack.h"
#include "pdf_file.h"
#include "pdf_dict.h"
#include "pdf_array.h"
#include "pdf_loop_detect.h"
#include "pdf_mark.h"
#include "pdf_obj.h"
#include "pdf_misc.h"
#include "pdf_page.h"
#include "pdf_deref.h"

#include "gscoord.h"         /* For gs_currentmatrix */

static int pdfi_get_named_dest(pdf_context *ctx, pdf_obj *Named, pdf_obj **Dest);

static int pdfi_pdfmark_setparam_obj(pdf_context *ctx, pdf_obj *obj, gs_param_string *entry)
{
    int code = 0;
    byte *data = NULL;
    int size = 0;

    code = pdfi_obj_to_string(ctx, obj, &data, &size);
    if (code < 0)
        return code;
    entry->data = data;
    entry->size = size;
    entry->persistent = false;
    return 0;
}

static int pdfi_pdfmark_setparam_pair(pdf_context *ctx, pdf_name *Key, pdf_obj *Value,
                                   gs_param_string *entry)
{
    int code = 0;

    /* Handle the Key */
    if (pdfi_type_of(Key) != PDF_NAME) {
        code = gs_note_error(gs_error_typecheck);
        goto exit;
    }

    code = pdfi_pdfmark_setparam_obj(ctx, (pdf_obj *)Key, entry);
    if (code < 0)
        goto exit;

    code = pdfi_pdfmark_setparam_obj(ctx, Value, entry+1);
    if (code < 0)
        goto exit;

 exit:
    return code;
}


/* Note: this isn't part of the obj_to_string() stuff */
static int pdfi_pdfmark_ctm_str(pdf_context *ctx, gs_matrix *ctm, byte **data, int *len)
{
    int size = 100;
    char *buf;

    buf = (char *)gs_alloc_bytes(ctx->memory, size, "pdfi_pdfmark_ctm_str(data)");
    if (buf == NULL)
        return_error(gs_error_VMerror);
    snprintf(buf, size, "[%.4f %.4f %.4f %.4f %.4f %.4f]",
             ctm->xx, ctm->xy, ctm->yx, ctm->yy, ctm->tx, ctm->ty);
    *data = (byte *)buf;
    *len = strlen(buf);
    return 0;
}

/* Write an string array command to the device (e.g. pdfmark) */
static int pdfi_pdfmark_write_array(pdf_context *ctx, gs_param_string_array *array_list, const char *command)
{
    gs_c_param_list list;
    int code;

    /* Set the list to writeable, and initialise it */
    gs_c_param_list_write(&list, ctx->memory);
    /* We don't want keys to be persistent, as we are going to throw
     * away our array, force them to be copied
     */
    gs_param_list_set_persistent_keys((gs_param_list *) &list, false);

    /* Make really sure the list is writable, but don't initialise it */
    gs_c_param_list_write_more(&list);

    /* Add the param string array to the list */
    code = param_write_string_array((gs_param_list *)&list, command, array_list);
    if (code < 0)
        return code;

    /* Set the param list back to readable, so putceviceparams can readit (mad...) */
    gs_c_param_list_read(&list);

    /* and set the actual device parameters */
    code = gs_putdeviceparams(ctx->pgs->device, (gs_param_list *)&list);

    gs_c_param_list_release(&list);

    return code;
}

/* Write an string array command to the device (e.g. pdfmark) */
static int pdfi_pdfmark_write_string(pdf_context *ctx, gs_param_string *param_string, const char *command)
{
    gs_c_param_list list;
    int code;

    /* Set the list to writeable, and initialise it */
    gs_c_param_list_write(&list, ctx->memory);
    /* We don't want keys to be persistent, as we are going to throw
     * away our array, force them to be copied
     */
    gs_param_list_set_persistent_keys((gs_param_list *) &list, false);

    /* Make really sure the list is writable, but don't initialise it */
    gs_c_param_list_write_more(&list);

    /* Add the param string array to the list */
    code = param_write_string((gs_param_list *)&list, command, param_string);
    if (code < 0)
        return code;

    /* Set the param list back to readable, so putceviceparams can readit (mad...) */
    gs_c_param_list_read(&list);

    /* and set the actual device parameters */
    code = gs_putdeviceparams(ctx->pgs->device, (gs_param_list *)&list);

    gs_c_param_list_release(&list);

    return code;
}

/* Apparently the strings to pass to the device are:
   key1 val1 .... keyN valN CTM "ANN"
   CTM is (for example) "[1.0 0 0 1.0 0 0]"

   This takes an optional 'label' argument which can be NULL.

   the /pdfmark command has this array of strings as a parameter, i.e.
   [ 'label' key1 val1 .... keyN valN CTM "ANN" ] /pdfmark

   Apparently the "type" doesn't have a leading "/" but the other names in the
   keys do need the "/"

   See plparams.c/process_pdfmark()
*/
static int pdfi_pdfmark_from_dict_withlabel(pdf_context *ctx, pdf_indirect_ref *label,
                                         pdf_dict *dict, gs_matrix *ctm, const char *type)
{
    int code = 0;
    int size;
    uint64_t dictsize;
    uint64_t index;
    uint64_t keynum = 0;
    int i;
    pdf_name *Key = NULL;
    pdf_obj *Value = NULL;
    pdf_obj *tempobj = NULL;
    gs_param_string *parray = NULL;
    gs_param_string_array array_list;
    byte *ctm_data = NULL;
    int ctm_len;
    gs_matrix ctm_placeholder;
    int offset = 0;

    /* If ctm not provided, make a placeholder */
    if (!ctm) {
        gs_currentmatrix(ctx->pgs, &ctm_placeholder);
        ctm = &ctm_placeholder;
    }

    dictsize = pdfi_dict_entries(dict);
    size = dictsize*2 + 2; /* pairs + CTM + type */
    if (label)
        size += 1;

    parray = (gs_param_string *)gs_alloc_bytes(ctx->memory, size*sizeof(gs_param_string),
                                               "pdfi_pdfmark_from_dict(parray)");
    if (parray == NULL) {
        code = gs_note_error(gs_error_VMerror);
        goto exit;
    }
    memset(parray, 0, size*sizeof(gs_param_string));

    if (label) {
        code = pdfi_pdfmark_setparam_obj(ctx, (pdf_obj *)label, parray+0);
        offset += 1;
    }

    /* Get each (key,val) pair from dict and setup param for it */
    if (dictsize > 0) {
        code = pdfi_dict_key_first(ctx, dict, (pdf_obj **)&Key, &index);
        while (code >= 0) {
            code = pdfi_dict_get_no_deref(ctx, dict, Key, &Value);
            if (code < 0) goto exit;

            code = pdfi_pdfmark_setparam_pair(ctx, Key, Value, parray+offset+(keynum*2));
            if (code < 0) goto exit;

            pdfi_countdown(Key);
            Key = NULL;
            pdfi_countdown(Value);
            Value = NULL;
            pdfi_countdown(tempobj);
            tempobj = NULL;

            code = pdfi_dict_key_next(ctx, dict, (pdf_obj **)&Key, &index);
            if (code == gs_error_undefined) {
                code = 0;
                break;
            }
            keynum ++;
        }
    }
    if (code < 0) goto exit;

    /* CTM */
    code = pdfi_pdfmark_ctm_str(ctx, ctm, &ctm_data, &ctm_len);
    if (code < 0) goto exit;
    parray[size-2].data = ctm_data;
    parray[size-2].size = ctm_len;

    /* Type (e.g. ANN, DOCINFO) */
    parray[size-1].data = (const byte *)type;
    parray[size-1].size = strlen(type);

    array_list.data = parray;
    array_list.persistent = false;
    array_list.size = size;

    code = pdfi_pdfmark_write_array(ctx, &array_list, "pdfmark");

 exit:
    pdfi_countdown(Key);
    pdfi_countdown(Value);
    pdfi_countdown(tempobj);
    if (parray != NULL) {
        /* Free the param data except the last two which are handled separately */
        for (i=0; i<size-2; i++) {
            if (parray[i].data)
                gs_free_object(ctx->memory, (byte *)parray[i].data, "pdfi_pdfmark_from_dict(parray)");
        }
    }
    if (ctm_data)
        gs_free_object(ctx->memory, ctm_data, "pdfi_pdfmark_from_dict(ctm_data)");
    gs_free_object(ctx->memory, parray, "pdfi_pdfmark_from_dict(parray)");
    return code;
}

/* Do a pdfmark from a dictionary */
int pdfi_pdfmark_from_dict(pdf_context *ctx, pdf_dict *dict, gs_matrix *ctm, const char *type)
{
    return pdfi_pdfmark_from_dict_withlabel(ctx, NULL, dict, ctm, type);
}

/* Does a pdfmark, from a c-array of pdf_obj's
 * This will put in a dummy ctm if none provided
 */
int pdfi_pdfmark_from_objarray(pdf_context *ctx, pdf_obj **objarray, int len,
                            gs_matrix *ctm, const char *type)
{
    int code = 0;
    int size;
    gs_param_string *parray = NULL;
    gs_param_string_array array_list;
    byte *ctm_data = NULL;
    int ctm_len;
    gs_matrix ctm_placeholder;
    int i;

    /* If ctm not provided, make a placeholder */
    if (!ctm) {
        gs_currentmatrix(ctx->pgs, &ctm_placeholder);
        ctm = &ctm_placeholder;
    }

    size = len + 2; /* data + CTM + type */

    parray = (gs_param_string *)gs_alloc_bytes(ctx->memory, size*sizeof(gs_param_string),
                                               "pdfi_pdfmark_from_objarray(parray)");
    if (parray == NULL) {
        code = gs_note_error(gs_error_VMerror);
        goto exit;
    }
    memset(parray, 0, size *sizeof(gs_param_string));

    for (i=0; i<len; i++) {
        code = pdfi_pdfmark_setparam_obj(ctx, objarray[i], parray+i);
        if (code < 0) goto exit;
    }

    /* CTM */
    code = pdfi_pdfmark_ctm_str(ctx, ctm, &ctm_data, &ctm_len);
    if (code < 0) goto exit;
    parray[len].data = ctm_data;
    parray[len].size = ctm_len;

    /* Type (e.g. ANN, DOCINFO) */
    parray[len+1].data = (const byte *)type;
    parray[len+1].size = strlen(type);

    array_list.data = parray;
    array_list.persistent = false;
    array_list.size = size;

    code = pdfi_pdfmark_write_array(ctx, &array_list, "pdfmark");

 exit:
    if (parray != NULL) {
        for (i=0; i<len; i++) {
            gs_free_object(ctx->memory, (byte *)parray[i].data, "pdfi_pdfmark_from_objarray(parray)");
        }
    }
    if (ctm_data)
        gs_free_object(ctx->memory, ctm_data, "pdfi_pdfmark_from_objarray(ctm_data)");
    gs_free_object(ctx->memory, parray, "pdfi_pdfmark_from_objarray(parray)");
    return code;
}

/* Send an arbitrary object as a string, with command 'cmd'
 * This is not a pdfmark, has no ctm.
 */
int pdfi_pdfmark_object(pdf_context *ctx, pdf_obj *object, const char *cmd)
{
    gs_param_string param_string;
    int code = 0;

    param_string.data = NULL;

    code = pdfi_loop_detector_mark(ctx);
    if (code < 0)
        goto exit;

    code = pdfi_resolve_indirect_loop_detect(ctx, NULL, object, true);
    (void)pdfi_loop_detector_cleartomark(ctx);
    if (code < 0)
        goto exit;

    code = pdfi_pdfmark_setparam_obj(ctx, object, &param_string);
    if (code < 0)
        goto exit;

    code = pdfi_pdfmark_write_string(ctx, &param_string, cmd);

exit:
    if (param_string.data != NULL)
        gs_free_object(ctx->memory, (byte *)param_string.data, "free data transferred to param_string in pdfi_pdfmark_object\n");
    return code;
}

/* Convert a Dest array to the hacky Page and View keys that pdfwrite expects
 * dest_array: [<page_ref> <view_info>]
 * page_ref: indirect ref to a page dict
 * view_info: see table 8.2 in PDF 1.7, for example "/Fit"
 *
 * Removes /Dest and inserts two key pairs: /Page N and /View <view_info>
 * N is the page number, which starts at 1, not 0.
 */
static int pdfi_pdfmark_add_Page_View(pdf_context *ctx, pdf_dict *link_dict, pdf_array *dest_array)
{
    int code = 0;
    int i;
    uint64_t page_num;
    pdf_dict *page_dict = NULL;
    pdf_array *view_array = NULL;
    uint64_t array_size;
    pdf_obj *temp_obj = NULL;

    /* Get the page_dict, without storing the deref in the array.
     * (This is needed because otherwise there could be a circular ref that will
     * lead to a memory leak)
     */
    code = pdfi_array_get_no_store_R(ctx, dest_array, 0, (pdf_obj **)&page_dict);
    if (code < 0) goto exit;

    if(pdfi_type_of(page_dict) == PDF_INT) {
        page_num = ((pdf_num *)page_dict)->value.i;
    } else {
        if (pdfi_type_of(page_dict) != PDF_DICT) {
            if (pdfi_type_of(page_dict) != PDF_NULL) {
                code = gs_note_error(gs_error_typecheck);
                goto exit;
            }
            page_num = 0;
        } else {
            /* Find out which page number this is */
            code = pdfi_page_get_number(ctx, page_dict, &page_num);
            if (code < 0) goto exit;
        }
    }

    page_num += ctx->Pdfmark_InitialPage;

    if (pdfi_type_of(page_dict) != PDF_NULL)
        /* Add /Page key to the link_dict
         * Of course pdfwrite is numbering its pages starting at 1, because... of course :(
         */
        code = pdfi_dict_put_int(ctx, link_dict, "Page", page_num+1);
    else
        code = pdfi_dict_put_int(ctx, link_dict, "Page", 0);

    if (code < 0)
        goto exit;

    /* Get and check the destination type, again without storing the deref in the array.
     * In this case a memory leak  can only happen if the destination
     * is an invalid type, but lets take no chances.
     */
    code = pdfi_array_get_no_store_R(ctx, dest_array, 1, &temp_obj);
    if (code < 0) goto exit;

    if (pdfi_type_of(temp_obj) != PDF_NAME) {
        pdfi_countdown(temp_obj);
        temp_obj = NULL;
        code = gs_note_error(gs_error_typecheck);
        goto exit;
    }
    pdfi_countdown(temp_obj);
    temp_obj = NULL;

    /* Build an array for /View, out of the remainder of the Dest entry */
    array_size = pdfi_array_size(dest_array) - 1;
    code = pdfi_array_alloc(ctx, array_size, &view_array);
    if (code < 0) goto exit;
    pdfi_countup(view_array);
    for (i=0; i<array_size; i++) {
        code = pdfi_array_get(ctx, dest_array, i+1, &temp_obj);
        if (code < 0) goto exit;
        code = pdfi_array_put(ctx, view_array, i, temp_obj);
        if (code < 0) goto exit;

        pdfi_countdown(temp_obj);
        temp_obj = NULL;
    }
    /* Add /View key to the link_dict */
    code = pdfi_dict_put(ctx, link_dict, "View", (pdf_obj *)view_array);
    if (code < 0) goto exit;

 exit:
    pdfi_countdown(temp_obj);
    pdfi_countdown(page_dict);
    pdfi_countdown(view_array);
    return code;
}

/* Lookup a Dest string(or name) in the Names array and try to resolve it */
static int pdfi_pdfmark_handle_dest_names(pdf_context *ctx, pdf_dict *link_dict,
                                         pdf_obj *dest, pdf_array *Names)
{
    int code = 0;
    int i;
    uint64_t array_size;
    pdf_obj *name = NULL;
    pdf_dict *D_dict = NULL;
    bool found = false;
    pdf_array *dest_array = NULL;

    array_size = pdfi_array_size(Names);

    /* Needs to be an even number - pairs of [name, obj] */
    if (array_size % 2 != 0) {
        /* TODO: flag an error? */
        /* Let's just ignore the last unpaired item for now */
        array_size -= 1;
    }

    for (i=0; i<array_size; i+=2) {
        code = pdfi_array_get(ctx, Names, i, (pdf_obj **)&name);
        if (code < 0) goto exit;
        /* Note: in current implementation, PDF_STRING and PDF_NAME have all the same
         * fields, but just in case that changes I treat them separately here.
         */
        if (pdfi_type_of(name) == PDF_STRING && pdfi_type_of(dest) == PDF_STRING) {
            if (!pdfi_string_cmp((pdf_string *)name, (pdf_string *)dest)) {
                found = true;
                break;
            }
        } else if (pdfi_type_of(name) == PDF_NAME && pdfi_type_of(dest) == PDF_NAME) {
            if (!pdfi_name_cmp((pdf_name *)name, (pdf_name *)dest)) {
                found = true;
                break;
            }
        }
        pdfi_countdown(name);
        name = NULL;
    }

    if (!found) {
        /* TODO: flag a warning? */
        code = 0;
        goto exit;
    }

    /* Next entry is either a dictionary (with a /D key) or an array */
    code = pdfi_array_get(ctx, Names, i+1, (pdf_obj **)&D_dict);
    if (code < 0) goto exit;

    switch (pdfi_type_of(D_dict)) {
        case PDF_DICT:
            /* Dict is supposed to contain key "D" with Dest array */
            code = pdfi_dict_knownget_type(ctx, D_dict, "D", PDF_ARRAY, (pdf_obj **)&dest_array);
            if (code <= 0) goto exit;
            break;
        case PDF_ARRAY:
            dest_array = (pdf_array *)D_dict;
            D_dict = NULL;
            break;
        default:
            code = gs_note_error(gs_error_typecheck);
            goto exit;
    }

    /* Process the dest_array to replace with /Page /View */
    code = pdfi_pdfmark_add_Page_View(ctx, link_dict, dest_array);
    if (code < 0) goto exit;

 exit:
    pdfi_countdown(name);
    pdfi_countdown(D_dict);
    pdfi_countdown(dest_array);
    return code;
}

/* Special handling for "Dest" in Links
 * Will replace /Dest with /Page /View in link_dict (for pdfwrite)
 */
int pdfi_pdfmark_modDest(pdf_context *ctx, pdf_dict *link_dict)
{
    int code = 0, code1 = 0;
    pdf_dict *Dests = NULL;
    pdf_obj *Dest = NULL;
    bool delete_Dest = true;
    pdf_array *dest_array = NULL;
    pdf_array *Names = NULL;
    pdf_dict *Names_dict = NULL;

    code = pdfi_dict_get(ctx, link_dict, "Dest", (pdf_obj **)&Dest);
    if (code < 0) goto exit;

    code = pdfi_dict_knownget_type(ctx, ctx->Root, "Dests", PDF_DICT, (pdf_obj **)&Dests);
    if (code < 0) goto exit;

    code = pdfi_dict_knownget_type(ctx, ctx->Root, "Names", PDF_DICT, (pdf_obj **)&Names_dict);
    if (code < 0) goto exit;

    switch (pdfi_type_of(Dest)) {
    case PDF_ARRAY:
        code = pdfi_pdfmark_add_Page_View(ctx, link_dict, (pdf_array *)Dest);
        if (code < 0) goto exit;
        break;
    case PDF_NAME:
        if (Dests != NULL) {
            /* Case where it's a name to look up in Contents(Root) /Dests */
            code = pdfi_dict_get_by_key(ctx, Dests, (const pdf_name *)Dest, (pdf_obj **)&dest_array);
            if (code == gs_error_undefined) {
                /* TODO: Not found, should flag a warning */
                code = 0;
                goto exit;
            }
            if (code < 0) goto exit;
            if (pdfi_type_of(dest_array) != PDF_ARRAY) {
                code = gs_note_error(gs_error_typecheck);
                goto exit;
            }
            code = pdfi_pdfmark_add_Page_View(ctx, link_dict, dest_array);
            if (code < 0) goto exit;
            break;
        }
        /* fallthrough */
    case PDF_STRING:
        if (Names_dict != NULL) {
            /* Looking in Catalog(Root) for /Names<</Dests<</Names [name dict array]>>>> */
            code = pdfi_dict_knownget_type(ctx, Names_dict, "Dests", PDF_DICT, (pdf_obj **)&Dests);
            if (code < 0) goto exit;
            if (code == 0) {
                /* TODO: Not found -- not sure if there is another case here or not */
                code = gs_note_error(gs_error_undefined);
                goto exit;
            }

            code = pdfi_dict_knownget_type(ctx, Dests, "Names", PDF_ARRAY, (pdf_obj **)&Names);
            if (code < 0) goto exit;
            if (code == 0) {
                code = pdfi_get_named_dest(ctx, Dest, (pdf_obj **)&dest_array);
                if (code < 0)
                    goto exit;
                if (pdfi_type_of(dest_array) == PDF_DICT) {
                    pdf_obj *D = NULL;
                    /* Dict is supposed to contain key "D" with Dest array */
                    code = pdfi_dict_knownget_type(ctx, (pdf_dict *)dest_array, "D", PDF_ARRAY, &D);
                    if (code <= 0) goto exit;

                    pdfi_countdown(dest_array);
                    dest_array = (pdf_array *)D;
                }
                if (pdfi_type_of(dest_array) == PDF_ARRAY) {
                    code = pdfi_pdfmark_add_Page_View(ctx, link_dict, dest_array);
                    if (code < 0)
                        goto exit;
                } else {
                    pdfi_set_error(ctx, 0, NULL, E_PDF_BAD_NAMED_DEST, "pdfi_pdfmark_modDest", NULL);
                }
                break;
            } else
                code = pdfi_pdfmark_handle_dest_names(ctx, link_dict, Dest, Names);
            if (code < 0) goto exit;
        } else {
            /* TODO: Ignore it -- flag a warning? */
        }
        break;
    default:
        /* TODO: Ignore it -- flag a warning? */
        break;
    }

 exit:
    if (delete_Dest) {
        /* Delete the Dest key */
        code1 = pdfi_dict_delete(ctx, link_dict, "Dest");
        if (code1 < 0 && code >= 0)
            code = code1;
    }
    pdfi_countdown(Dest);
    pdfi_countdown(Dests);
    pdfi_countdown(Names);
    pdfi_countdown(Names_dict);
    pdfi_countdown(dest_array);
    return code;
}

static int pdfi_check_limits(pdf_context *ctx, pdf_dict *node, char *str, int len)
{
    int code = 0, min, i, len2 = 0;
    pdf_array *Limits = NULL;
    pdf_string *Str = NULL;
    char *str2 = NULL;

    code = pdfi_dict_get_type(ctx, node, "Limits", PDF_ARRAY, (pdf_obj **)&Limits);
    if (code < 0)
        goto error;

    if (pdfi_array_size(Limits) != 2) {
        /* Limits are not valid, just ignore them. The calling code will then check
         * the Names array.
         */
        pdfi_set_warning(ctx, 0, NULL, W_PDF_BAD_TREE_LIMITS, "pdfi_check_limits", 0);
        goto error;
    }

    code = pdfi_array_get_type(ctx, Limits, 0, PDF_STRING, (pdf_obj **)&Str);
    if (code < 0)
        goto error;

    if (pdfi_type_of(Str) == PDF_NAME) {
        code = pdfi_string_from_name(ctx, (pdf_name *)Str, &str2, &len2);
        if (code < 0)
            return code;
    } else {
        len2 = ((pdf_string *)Str)->length;
        str2 = (char *)gs_alloc_bytes(ctx->memory, len2 + 1, "pdfi_check_limits");
        if (str2 == NULL) {
            code = gs_note_error(gs_error_VMerror);
            goto error;
        }
         memcpy(str2, ((pdf_string *)Str)->data, len2);
         str2[len2] = 0;
    }

    pdfi_countdown(Str);
    Str = NULL;

    min = len;
    if (len2 < min)
        min = len2;

    for (i=0;i< min;i++) {
        if (str[i] < str2[i]) {
            code = gs_note_error(gs_error_undefined);
            goto error;
        }
        if (str[i] != str2[i])
            break;
    }
    if (i > min && len2 < Str->length) {
        code = gs_note_error(gs_error_undefined);
        goto error;
    }
    gs_free_object(ctx->memory, str2, "pdfi_check_limits");
    str2 = NULL;

    code = pdfi_array_get_type(ctx, Limits, 1, PDF_STRING, (pdf_obj **)&Str);
    if (code < 0)
        goto error;

    if (pdfi_type_of(Str) == PDF_NAME) {
        code = pdfi_string_from_name(ctx, (pdf_name *)Str, &str2, &len2);
        if (code < 0)
            return code;
    } else {
        len2 = ((pdf_string *)Str)->length;
        str2 = (char *)gs_alloc_bytes(ctx->memory, len2 + 1, "pdfi_check_limits");
        if (str2 == NULL) {
            code = gs_note_error(gs_error_VMerror);
            goto error;
        }
         memcpy(str2, ((pdf_string *)Str)->data, len2);
         str2[len2] = 0;
    }

    pdfi_countdown(Str);
    Str = NULL;

    min = len;
    if (len2 < min)
        min = len2;

    for (i=0;i< min;i++) {
        if (str[i] > str2[i]) {
            code = gs_note_error(gs_error_undefined);
            goto error;
        }
        if (str[i] != str2[i])
            break;
    }

    if (i > min && len > len2)
        code = gs_note_error(gs_error_undefined);

error:
    gs_free_object(ctx->memory, str2, "pdfi_check_limits");
    pdfi_countdown(Str);
    pdfi_countdown(Limits);
    return code;
}

static int pdfi_get_name_from_node(pdf_context *ctx, pdf_dict *node, char *str, int len, pdf_obj **Name, bool is_root)
{
    int i = 0, code = 0;
    pdf_string *StrKey = NULL;
    pdf_array *NamesArray = NULL;
    pdf_dict *Kid = NULL;
    bool known;

    code = pdfi_loop_detector_mark(ctx);
    if (code < 0)
        return code;

    code = pdfi_dict_known(ctx, node, "Names", &known);
    if (code < 0)
        goto error;

    if (known) {
        code = pdfi_dict_known(ctx, node, "Limits", &known);
        if (code < 0)
            goto error;

        if (!known) {
            if (!is_root)
                /* No Limits array (a required entry, except in the Root), so just assume that the
                 * string is in this node and check all the Names anyway
                 */
                pdfi_set_warning(ctx, 0, NULL, W_PDF_NO_TREE_LIMITS, "pdfi_get_name_from_node", 0);
        } else {
            code = pdfi_check_limits(ctx, node, str, len);
            if (code < 0)
                goto error;
        }

        code = pdfi_dict_get_type(ctx, node, "Names", PDF_ARRAY, (pdf_obj **)&NamesArray);
        if (code < 0)
            goto error;

        if (pdfi_array_size(NamesArray) & 1)
            pdfi_set_warning(ctx, 0, NULL, W_PDF_NAMES_ARRAY_SIZE, "pdfi_get_name_from_node", 0);

        for (i = 0;i < pdfi_array_size(NamesArray) / 2; i++) {
            code = pdfi_array_get_type(ctx, NamesArray, i * 2, PDF_STRING, (pdf_obj **)&StrKey);
            if (code < 0)
                goto error;

            if (StrKey->length == len && memcmp((const char *)StrKey->data, str, len) == 0) {
                code = pdfi_array_get(ctx, NamesArray, (i * 2) + 1, (pdf_obj **)Name);
                goto error;
            }
            pdfi_countdown(StrKey);
            StrKey = NULL;
        }
        pdfi_countdown(NamesArray);
        NamesArray = NULL;
    }

    /* Either no Names array (initial node) or not in array */
    code = pdfi_dict_get_type(ctx, node, "Kids", PDF_ARRAY, (pdf_obj **)&NamesArray);
    if (code < 0)
        goto error;

    for (i = 0;i < pdfi_array_size(NamesArray); i++) {
        code = pdfi_array_get_type(ctx, NamesArray, i, PDF_DICT, (pdf_obj **)&Kid);
        if (code < 0)
            goto error;

        code = pdfi_get_name_from_node(ctx, Kid, str, len, Name, false);
        pdfi_countdown(Kid);
        Kid = NULL;
        if (code == 0)
            break;

        if (code < 0) {
            if (code == gs_error_undefined)
                continue;
            goto error;
        }
    }

error:
    pdfi_countdown(Kid);
    pdfi_countdown(StrKey);
    pdfi_countdown(NamesArray);
    (void)pdfi_loop_detector_cleartomark(ctx);
    return code;
}

static int pdfi_get_named_dest(pdf_context *ctx, pdf_obj *Named, pdf_obj **Dest)
{
    int code = 0, len = 0;
    pdf_dict *Names = NULL, *Dests = NULL;
    char *str = NULL;

    code = pdfi_loop_detector_mark(ctx);
    if (code < 0)
        return code;

    code = pdfi_dict_get_type(ctx, ctx->Root, "Names", PDF_DICT, (pdf_obj **)&Names);
    if (code < 0)
        goto error;

    code = pdfi_dict_get_type(ctx, Names, "Dests", PDF_DICT, (pdf_obj **)&Dests);
    if (code < 0)
        goto error;

    if (pdfi_type_of(Named) == PDF_NAME) {
        code = pdfi_string_from_name(ctx, (pdf_name *)Named, &str, &len);
        if (code < 0)
            return code;
    } else {
        len = ((pdf_string *)Named)->length;
        str = (char *)gs_alloc_bytes(ctx->memory, len + 1, "pdfi_get_named_dest");
        if (str == NULL) {
            code = gs_note_error(gs_error_VMerror);
            goto error;
        }
        memcpy(str, ((pdf_string *)Named)->data, len);
        str[len] = 0;
    }

    code = pdfi_get_name_from_node(ctx, Dests, str, len, Dest, true);

error:
    if (pdfi_type_of(Named) == PDF_NAME)
        (void)pdfi_free_string_from_name(ctx, str);
    else
        gs_free_object(ctx->memory, str, "pdfi_get_named_dest");
    pdfi_countdown(Names);
    pdfi_countdown(Dests);
    pdfi_loop_detector_cleartomark(ctx);
    return code;
}

/* Special handling for "A" in Link annotations and Outlines
 * Will delete A if handled and if A_key is provided.
 */
int pdfi_pdfmark_modA(pdf_context *ctx, pdf_dict *dict)
{
    int code = 0;
    pdf_dict *A_dict = NULL;
    bool known;
    pdf_name *S_name = NULL;
    pdf_array *D_array = NULL;
    bool delete_A = false;
    bool deref_A = true;

    code = pdfi_dict_get_no_store_R(ctx, dict, "A", (pdf_obj **)&A_dict);
    if (code < 0) goto exit;

    if (pdfi_type_of(A_dict) != PDF_DICT) {
        /* Invalid AP, just delete it because I dunno what to do...
         * TODO: Should flag a warning here
         */
        delete_A = true;
        goto exit;
    }

    /* Handle URI */
    code = pdfi_dict_known(ctx, A_dict, "URI", &known);
    if (code < 0) goto exit;
    if (known) {
        code = pdfi_resolve_indirect_loop_detect(ctx, (pdf_obj *)NULL, (pdf_obj *)A_dict, true);
        goto exit;
    }

    /* Handle S = GoTo */
    /* TODO: this handles <</S /GoTo /D [dest array]>>
     * Not sure if there are other cases to handle?
     */
    code = pdfi_dict_knownget_type(ctx, A_dict, "S", PDF_NAME, (pdf_obj **)&S_name);
    if (code <= 0) goto exit;
    /* We only handle GoTo for now */
    if (pdfi_name_is(S_name, "GoTo")) {
        code = pdfi_dict_knownget(ctx, A_dict, "D", (pdf_obj **)&D_array);
        if (code <= 0)
            goto exit;
        if (pdfi_type_of(D_array) == PDF_STRING || pdfi_type_of(D_array) == PDF_NAME)
        {
            pdf_obj *Dest = NULL;

            code = pdfi_get_named_dest(ctx, (pdf_obj *)D_array, &Dest);
            if (code < 0)
                goto exit;
            pdfi_countdown(D_array);
            D_array = NULL;
            if (pdfi_type_of(Dest) != PDF_ARRAY) {
                if (pdfi_type_of(Dest) != PDF_DICT) {
                    pdfi_countdown(Dest);
                    code = gs_note_error(gs_error_typecheck);
                    goto exit;
                }
                code = pdfi_dict_knownget(ctx, (pdf_dict *)Dest, "D", (pdf_obj **)&D_array);
                pdfi_countdown(Dest);
                if (code <= 0)
                    goto exit;
            } else
                D_array = (pdf_array *)Dest;
        }
        if (pdfi_type_of(D_array) != PDF_ARRAY) {
            code = gs_note_error(gs_error_typecheck);
            goto exit;
        }

        /* Process the D array to replace with /Page /View */
        code = pdfi_pdfmark_add_Page_View(ctx, dict, D_array);
        if (code < 0) goto exit;
        delete_A = true;
    } else if (pdfi_name_is(S_name, "GoToR") || pdfi_name_is(S_name, "Launch")) {
        /* These point out of the document.
         * Flatten out the reference, but otherwise leave it alone.
         * gs does some wack stuff here.
         *
         * Currently this is same behavior as gs, but it is not correct behavior.
         * In at least some cases we could do better, for example if the doc
         * pointed to happens to be the same file.
         * Sample: fts_28_2808.pdf
         * Sample: ~/work/samples/tests_private/pdf/sumatra/1874_-_clicking_ToC_link_crashes.pdf
         */
        code = pdfi_resolve_indirect_loop_detect(ctx, (pdf_obj *)dict, (pdf_obj *)A_dict, true);
        delete_A = false;
        code = 0;
    } else if (pdfi_name_is(S_name, "Named")) {
        /* We can just pass this through and it will work fine
         * This should be a name like "FirstPage" or "LastPage".
         * Note: gs implementation translates into page numbers and also has some bugs...
         * Sample: fts_33_3310.pdf
         */
        delete_A = false;
        code = 0;
    } else if (pdfi_name_is(S_name, "GoToE")) {
        /* TODO: ??
         * File: fts_33_3303.pdf
         */
    } else if (pdfi_name_is(S_name, "Thread")) {
        /* TODO: For basically all of these below, I think just need to preserve
         * any references and streams and pass it all through.
         * File: fts_33_3305.pdf fts_33_3317.pdf
         */
        deref_A = false;
    } else if (pdfi_name_is(S_name, "Sound")) {
        /* TODO: ??
         * File: fts_33_3307.pdf
         */
        deref_A = false;
    } else if (pdfi_name_is(S_name, "Movie")) {
        /* TODO: ??
         * File: fts_33_3308.pdf
         */
        deref_A = false;
    } else if (pdfi_name_is(S_name, "GoTo3DView")) {
        /* TODO: ??
         * File: fts_33_3318.pdf
         */
    } else if (pdfi_name_is(S_name, "RichMediaExecute")) {
        /* TODO: ??
         * File: fts_33_3319.pdf
         */
    } else if (pdfi_name_is(S_name, "Rendition")) {
        /* TODO: make sure to pass through accurately?
         * File: fts_07_0709.pdf fts_33_3316.pdf
         */
    } else {
        /* TODO: flag warning? */
    }

 exit:
    if (delete_A) {
        code = pdfi_dict_delete(ctx, dict, "A");
    } else if (deref_A) {
        pdfi_countdown(A_dict);
        A_dict = NULL;
    }
    pdfi_countdown(A_dict);
    pdfi_countdown(S_name);
    pdfi_countdown(D_array);
    return code;
}

/* Begin defining an object
 * Send an OBJ (_objdef) command
 * (_objdef) (<label>) (/type) (/<type>) OBJ
 */
static int pdfi_pdfmark_objdef_begin(pdf_context *ctx, pdf_indirect_ref *label, const char *type)
{
    int code;
    pdf_obj *objarray[4];
    int num_objects = 4;
    int i;

    memset(objarray, 0, sizeof(objarray));

    code = pdfi_obj_charstr_to_name(ctx, "_objdef", (pdf_name **)&objarray[0]);
    if (code < 0) goto exit;

    objarray[1] = (pdf_obj *)label;
    pdfi_countup(label);

    code = pdfi_obj_charstr_to_name(ctx, "type", (pdf_name **)&objarray[2]);
    if (code < 0) goto exit;

    code = pdfi_obj_charstr_to_name(ctx, type, (pdf_name **)&objarray[3]);
    if (code < 0) goto exit;

    code = pdfi_pdfmark_from_objarray(ctx, objarray, num_objects, NULL, "OBJ");
    if (code < 0) goto exit;

 exit:
    for (i=0; i<num_objects; i++)
        pdfi_countdown(objarray[i]);
    return code;
}

/* Close an object
 * Send a CLOSE command
 * (<label>) CLOSE
 */
static int pdfi_pdfmark_objdef_close(pdf_context *ctx, pdf_indirect_ref *label)
{
    int code;
    pdf_obj *objarray[1];
    int num_objects = 1;
    int i;

    memset(objarray, 0, sizeof(objarray));

    objarray[0] = (pdf_obj *)label;
    pdfi_countup(label);

    code = pdfi_pdfmark_from_objarray(ctx, objarray, num_objects, NULL, "CLOSE");
    if (code < 0) goto exit;

 exit:
    for (i=0; i<num_objects; i++)
        pdfi_countdown(objarray[i]);
    return code;
}

static int pdfi_pdfmark_stream_contents(pdf_context *ctx, pdf_indirect_ref *label, pdf_stream *stream)
{
    int code;
    pdf_obj *objarray[2];
    int num_objects = 2;
    int i;

    objarray[0] = (pdf_obj *)label;
    pdfi_countup(label);

    objarray[1] = (pdf_obj *)stream;
    pdfi_countup(stream);
    stream->is_marking = true;

    code = pdfi_pdfmark_from_objarray(ctx, objarray, num_objects, NULL, ".PUTSTREAM");
    if (code < 0) goto exit;

 exit:
    stream->is_marking = false;
    for (i=0; i<num_objects; i++)
        pdfi_countdown(objarray[i]);
    return code;
}

/* Mark a stream object */
int pdfi_pdfmark_stream(pdf_context *ctx, pdf_stream *stream)
{
    int code;
    pdf_dict *streamdict = NULL;
    pdf_indirect_ref *streamref = NULL;
    pdf_dict *tempdict = NULL;
    uint64_t dictsize;
    uint64_t index;
    pdf_name *Key = NULL;

    if (stream->stream_written)
        return 0;

    stream->stream_written = true;

    if (!ctx->device_state.writepdfmarks)
        return 0;

    /* Create an indirect ref for the stream */
    code = pdfi_object_alloc(ctx, PDF_INDIRECT, 0, (pdf_obj **)&streamref);
    if (code < 0) goto exit;
    pdfi_countup(streamref);
    streamref->ref_object_num = stream->object_num;
    streamref->ref_generation_num = stream->generation_num;
    streamref->is_marking = true;

    code = pdfi_dict_from_obj(ctx, (pdf_obj *)stream, &streamdict);
    if (code < 0) goto exit;

    /* Make a copy of the dict and remove Filter keyword */
    dictsize = pdfi_dict_entries(streamdict);
    code = pdfi_dict_alloc(ctx, dictsize, &tempdict);
    if (code < 0) goto exit;
    pdfi_countup(tempdict);
    code = pdfi_dict_copy(ctx, tempdict, streamdict);
    if (code < 0) goto exit;
    code = pdfi_dict_key_first(ctx, streamdict, (pdf_obj **)&Key, &index);
    while (code >= 0) {
        if (pdfi_name_is(Key, "Filter") || pdfi_name_is(Key, "Length")) {
            code = pdfi_dict_delete_pair(ctx, tempdict, Key);
            if (code < 0) goto exit;
        }
        pdfi_countdown(Key);
        Key = NULL;

        code = pdfi_dict_key_next(ctx, streamdict, (pdf_obj **)&Key, &index);
        if (code == gs_error_undefined) {
            code = 0;
            break;
        }
    }
    if (code < 0) goto exit;

    code = pdfi_pdfmark_objdef_begin(ctx, streamref, "stream");
    if (code < 0) goto exit;

    code = pdfi_pdfmark_from_dict_withlabel(ctx, streamref, tempdict, NULL, ".PUTDICT");
    if (code < 0) goto exit;

    code = pdfi_pdfmark_stream_contents(ctx, streamref, stream);
    if (code < 0) goto exit;

    code = pdfi_pdfmark_objdef_close(ctx, streamref);
    if (code < 0) goto exit;

 exit:
    pdfi_countdown(tempdict);
    pdfi_countdown(streamref);
    return code;
}

/* Mark a dict object */
int pdfi_pdfmark_dict(pdf_context *ctx, pdf_dict *dict)
{
    int code;
    pdf_indirect_ref *dictref = NULL;

    if (dict->dict_written)
        return 0;

    dict->dict_written = true;

    if (!ctx->device_state.writepdfmarks)
        return 0;

    /* Create an indirect ref for the dict */
    code = pdfi_object_alloc(ctx, PDF_INDIRECT, 0, (pdf_obj **)&dictref);
    if (code < 0) goto exit;
    pdfi_countup(dictref);
    dictref->ref_object_num = dict->object_num;
    dictref->ref_generation_num = dict->generation_num;
    dictref->is_marking = true;

    code = pdfi_pdfmark_objdef_begin(ctx, dictref, "dict");
    if (code < 0) goto exit;

    code = pdfi_pdfmark_from_dict_withlabel(ctx, dictref, dict, NULL, ".PUTDICT");
    if (code < 0) goto exit;

 exit:
    pdfi_countdown(dictref);
    return code;
}

static int pdfi_pdfmark_filespec(pdf_context *ctx, pdf_string *name, pdf_dict *filespec)
{
    int code;
    pdf_dict *tempdict = NULL;

    code = pdfi_dict_alloc(ctx, 40, &tempdict);
    if (code < 0) goto exit;
    pdfi_countup(tempdict);

    code = pdfi_dict_put(ctx, tempdict, "Name", (pdf_obj *)name);
    if (code < 0) goto exit;

    /* Flatten the filespec */
    code = pdfi_resolve_indirect(ctx, (pdf_obj *)filespec, true);
    if (code < 0) goto exit;

    code = pdfi_dict_put(ctx, tempdict, "FS", (pdf_obj *)filespec);
    if (code < 0) goto exit;

    code = pdfi_pdfmark_from_dict(ctx, tempdict, NULL, "EMBED");
    if (code < 0) goto exit;

 exit:
    pdfi_countdown(tempdict);
    return code;
}

/* embed a file */
int pdfi_pdfmark_embed_filespec(pdf_context *ctx, pdf_string *name, pdf_dict *filespec)
{
    int code;

    code = pdfi_pdfmark_filespec(ctx, name, filespec);
    if (code < 0) goto exit;

 exit:
    return code;
}

/*
 * Create and emit a /DOCINFO pdfmark for any and all of Title,
 * Author, Subject, Keywords and Creator
 */
void pdfi_pdfmark_write_docinfo(pdf_context *ctx, pdf_dict *info_dict)
{
    int i, code = 0;
    pdf_dict *Info = NULL;
    pdf_obj *o = NULL;
    /* We don't preserve the Producer, we are the Producer */
    const char *KeyNames[] = {
        "Title", "Author", "Subject", "Keywords", "Creator"
    };

    if (!ctx->device_state.writepdfmarks)
        return;

    code = pdfi_dict_alloc(ctx, 5, &Info);
    if (code < 0)
        goto exit;
    pdfi_countup(Info);

    for (i=0;i<5;i++)
    {
        if (pdfi_dict_knownget(ctx, info_dict, KeyNames[i], &o) > 0)
        {
            (void)pdfi_dict_put(ctx, Info, KeyNames[i], (pdf_obj *)o);
            pdfi_countdown(o);
        }
    }

    code = pdfi_pdfmark_from_dict(ctx, Info, NULL, "DOCINFO");
exit:
    pdfi_countdown(Info);
    return;
}

/*
 * Create and emit a /PAGE pdfmark for any and all of
 * CropBox, TrimBox, Artbox and BleedBox. If the interpreter
 * has used something other than the MediaBox as the media size, then
 * we don't send these, they are almost certainly incorrect.
 *
 * Because we will have used the MediaBox to create the media size, and
 * will have accounted for any rotation or scaling, we can use the CTM
 * to adjust the various Box entries (note this routine must be called
 * early!).
 */
void pdfi_pdfmark_write_boxes(pdf_context *ctx, pdf_dict *page_dict)
{
    int i, code = 0;
    pdf_dict *BoxDict = NULL;
    pdf_obj *o = NULL;
    gx_device *device = gs_currentdevice(ctx->pgs);
    gs_matrix scale, m, ctm;
    const char *BoxNames[] = {
        "CropBox", "BleedBox", "TrimBox", "ArtBox"
    };

    /* If the device doesn't support pdfmark, or the device modifies the Page Size (making the other boxes unreliable) exit now */
    if (!ctx->device_state.writepdfmarks || ctx->device_state.ModifiesPageSize)
        return;

    /* If we are using somethign other than the MediaBox, don't send these */
    if (ctx->args.usecropbox || ctx->args.usebleedbox ||
        ctx->args.usetrimbox || ctx->args.useartbox)
        return;

    code = pdfi_dict_alloc(ctx, 4, &BoxDict);
    if (code < 0)
        goto exit;

    pdfi_countup(BoxDict);

    /* Undo the resolution scaling from the CTM, we don't want to apply that */
    scale.xx = 72.0 / device->HWResolution[0];
    scale.xy = 0;
    scale.yx = 0;
    scale.yy = 72.0 / device->HWResolution[1];
    scale.tx = 0;
    scale.ty = 0;

    /* And multiply that by the CTM to get a matrix which represents the
     * scaling/rotation used to set the conetnt to the media.
     */
    gs_currentmatrix(ctx->pgs, &ctm);
    code = gs_matrix_multiply(&ctm, &scale, &m);
    if (code < 0) goto exit;

    for (i=0;i<4;i++)
    {
        /* Check each Bos name in turn */
        if (pdfi_dict_knownget(ctx, page_dict, BoxNames[i], &o) > 0){
            gs_rect box;
            pdf_array *new_array = NULL;

            /* Box is present in page dicitonayr, check it's an array */
            if (pdfi_type_of(o) != PDF_ARRAY) {
                pdfi_countdown(o);
                continue;
            }

            /* Turn the contents into a gs_rect */
            code = pdfi_array_to_gs_rect(ctx, (pdf_array *)o, &box);
            pdfi_countdown(o);
            if (code < 0)
                continue;

            /* Rectangles in PDF need not be llx,lly,urx,ury, they can be any
             * two opposite corners. Turn that into the usual format.
             */
            pdfi_normalize_rect(ctx, &box);

            /* Transform the resulting box by the calculated matrix */
            pdfi_bbox_transform(ctx, &box, &m);

            /* Get a new array created from the box values */
            code = pdfi_gs_rect_to_array(ctx, &box, &new_array);
            if (code < 0)
                continue;

            /* And store it in the working dictionary */
            (void)pdfi_dict_put(ctx, BoxDict, BoxNames[i], (pdf_obj *)new_array);
            pdfi_countdown(new_array);
        }
    }

    /* Send all the Box entries to the device */
    (void)pdfi_pdfmark_from_dict(ctx, BoxDict, NULL, "PAGE");

exit:
    pdfi_countdown(BoxDict);
    return;
}
