#include "fitz-internal.h"
#include "mupdf-internal.h"

struct pdf_js_s
{
	pdf_document *doc;
	pdf_obj *form;
	pdf_js_event event;
	pdf_jsimp *imp;
	pdf_jsimp_type *doctype;
	pdf_jsimp_type *eventtype;
	pdf_jsimp_type *fieldtype;
};

static pdf_obj *load_color(fz_context *ctx, pdf_jsimp *imp, pdf_jsimp_obj *val)
{
	pdf_obj *col = NULL;

	if (pdf_jsimp_array_len(imp, val) == 4)
	{
		pdf_obj *comp = NULL;
		pdf_jsimp_obj *jscomp = NULL;
		int i;

		col = pdf_new_array(ctx, 3);

		fz_var(comp);
		fz_var(jscomp);
		fz_try(ctx)
		{
			for (i = 0; i < 3; i++)
			{
				jscomp = pdf_jsimp_array_item(imp, val, i+1);
				comp = pdf_new_real(ctx, pdf_jsimp_toNumber(imp, jscomp));
				pdf_array_push(col, comp);
				pdf_jsimp_drop_obj(imp, jscomp);
				jscomp = NULL;
				pdf_drop_obj(comp);
				comp = NULL;
			}
		}
		fz_catch(ctx)
		{
			pdf_jsimp_drop_obj(imp, jscomp);
			pdf_drop_obj(comp);
			pdf_drop_obj(col);
			fz_rethrow(ctx);
		}
	}

	return col;
}

static pdf_jsimp_obj *field_buttonSetCaption(void *jsctx, void *obj, int argc, pdf_jsimp_obj *args[])
{
	pdf_js  *js = (pdf_js *)jsctx;
	pdf_obj *field = (pdf_obj *)obj;
	char    *name;

	if (argc != 1)
		return NULL;

	name = pdf_jsimp_toString(js->imp, args[0]);
	pdf_field_buttonSetCaption(js->doc, field, name);

	return NULL;
}

static pdf_jsimp_obj *field_getFillColor(void *jsctx, void *obj)
{
	return NULL;
}

static void field_setFillColor(void *jsctx, void *obj, pdf_jsimp_obj *val)
{
	pdf_js *js = (pdf_js *)jsctx;
	fz_context *ctx = js->doc->ctx;
	pdf_obj *field = (pdf_obj *)obj;
	pdf_obj *col = load_color(js->doc->ctx, js->imp, val);

	fz_try(ctx)
	{
		pdf_field_setFillColor(js->doc, field, col);
	}
	fz_always(ctx)
	{
		pdf_drop_obj(col);
	}
	fz_catch(ctx)
	{
		fz_rethrow(ctx);
	}
}

static pdf_jsimp_obj *field_getTextColor(void *jsctx, void *obj)
{
	return NULL;
}

static void field_setTextColor(void *jsctx, void *obj, pdf_jsimp_obj *val)
{
	pdf_js *js = (pdf_js *)jsctx;
	fz_context *ctx = js->doc->ctx;
	pdf_obj *field = (pdf_obj *)obj;
	pdf_obj *col = load_color(js->doc->ctx, js->imp, val);

	fz_try(ctx)
	{
		pdf_field_setTextColor(js->doc, field, col);
	}
	fz_always(ctx)
	{
		pdf_drop_obj(col);
	}
	fz_catch(ctx)
	{
		fz_rethrow(ctx);
	}
}

static pdf_jsimp_obj *field_getBorderStyle(void *jsctx, void *obj)
{
	pdf_js *js = (pdf_js *)jsctx;
	pdf_obj *field = (pdf_obj *)obj;

	return pdf_jsimp_fromString(js->imp, pdf_field_getBorderStyle(js->doc, field));
}

static void field_setBorderStyle(void *jsctx, void *obj, pdf_jsimp_obj *val)
{
	pdf_js *js = (pdf_js *)jsctx;
	pdf_obj *field = (pdf_obj *)obj;

	pdf_field_setBorderStyle(js->doc, field, pdf_jsimp_toString(js->imp, val));
}

static pdf_jsimp_obj *field_getValue(void *jsctx, void *obj)
{
	pdf_js *js = (pdf_js *)jsctx;
	pdf_obj *field = (pdf_obj *)obj;
	char *fval = pdf_field_getValue(js->doc, field);

	return pdf_jsimp_fromString(js->imp, fval?fval:"");
}

static void field_setValue(void *jsctx, void *obj, pdf_jsimp_obj *val)
{
	pdf_js *js = (pdf_js *)jsctx;
	pdf_obj *field = (pdf_obj *)obj;

	(void)pdf_field_setValue(js->doc, field, pdf_jsimp_toString(js->imp, val));
}

static pdf_jsimp_obj *event_getTarget(void *jsctx, void *obj)
{
	pdf_js *js = (pdf_js *)jsctx;

	return pdf_jsimp_new_obj(js->imp, js->fieldtype, js->event.target);
}

static void event_setTarget(void *jsctx, void *obj, pdf_jsimp_obj *val)
{
	pdf_js *js = (pdf_js *)jsctx;
	fz_warn(js->doc->ctx, "Unexpected call to event_setTarget");
}

static pdf_jsimp_obj *event_getValue(void *jsctx, void *obj)
{
	pdf_js *js = (pdf_js *)jsctx;
	char *v = js->event.value;

	return pdf_jsimp_fromString(js->imp, v?v:"");
}

static void event_setValue(void *jsctx, void *obj, pdf_jsimp_obj *val)
{
	pdf_js *js = (pdf_js *)jsctx;
	fz_context *ctx = js->doc->ctx;
	fz_free(ctx, js->event.value);
	js->event.value = NULL;
	js->event.value = fz_strdup(ctx, pdf_jsimp_toString(js->imp, val));
}

static pdf_jsimp_obj *event_getWillCommit(void *jsctx, void *obj)
{
	pdf_js *js = (pdf_js *)jsctx;

	return pdf_jsimp_fromNumber(js->imp, 1.0);
}

static void event_setWillCommit(void *jsctx, void *obj, pdf_jsimp_obj *val)
{
	pdf_js *js = (pdf_js *)jsctx;
	fz_warn(js->doc->ctx, "Unexpected call to event_setWillCommit");
}

static pdf_jsimp_obj *event_getRC(void *jsctx, void *obj)
{
	pdf_js *js = (pdf_js *)jsctx;

	return pdf_jsimp_fromNumber(js->imp, (double)js->event.rc);
}

static void event_setRC(void *jsctx, void *obj, pdf_jsimp_obj *val)
{
	pdf_js *js = (pdf_js *)jsctx;

	js->event.rc = (int)pdf_jsimp_toNumber(js->imp, val);
}

static pdf_jsimp_obj *doc_getEvent(void *jsctx, void *obj)
{
	pdf_js *js = (pdf_js *)jsctx;

	return pdf_jsimp_new_obj(js->imp, js->eventtype, &js->event);
}

static void doc_setEvent(void *jsctx, void *obj, pdf_jsimp_obj *val)
{
	pdf_js *js = (pdf_js *)jsctx;
	fz_warn(js->doc->ctx, "Unexpected call to doc_setEvent");
}

static pdf_obj *find_field(pdf_obj *dict, char *name, int len)
{
	pdf_obj *field;

	int i, n = pdf_array_len(dict);

	for (i = 0; i < n; i++)
	{
		char *part;

		field = pdf_array_get(dict, i);
		part = pdf_to_str_buf(pdf_dict_gets(field, "T"));
		if (strlen(part) == len && !memcmp(part, name, len))
			break;
	}

	return i < n ? field : NULL;
}

static char *utf8_to_pdf(fz_context *ctx, char *utf8)
{
	char *pdf = fz_malloc(ctx, strlen(utf8)+1);
	int i = 0;
	char c;

	while ((c = *utf8) != 0)
	{
		if ((c & 0x80) == 0 && pdf_doc_encoding[c] == c)
		{
			pdf[i++] = c;
			utf8++ ;
		}
		else
		{
			int rune;
			int j;

			utf8 += fz_chartorune(&rune, utf8);

			for (j = 0; j < sizeof(pdf_doc_encoding) && pdf_doc_encoding[j] != rune; j++)
				;

			if (j < sizeof(pdf_doc_encoding))
				pdf[i++] = j;
		}
	}

	pdf[i] = 0;

	return pdf;
}

static pdf_jsimp_obj *doc_getField(void *jsctx, void *obj, int argc, pdf_jsimp_obj *args[])
{
	pdf_js  *js = (pdf_js *)jsctx;
	fz_context *ctx = js->doc->ctx;
	pdf_obj *arr = js->form;
	pdf_obj *dict = NULL;
	int len;
	char *utf8, *dot;
	char *name = NULL;
	char *namep;

	if (argc != 1)
		return NULL;

	fz_var(dict);
	fz_var(name);
	fz_try(ctx)
	{
		utf8 = pdf_jsimp_toString(js->imp, args[0]);

		if (utf8)
		{
			name = utf8_to_pdf(ctx, utf8);

			/* Process the fully qualified field name which has
			* the partial names delimited by '.'. Pretend there
			* was a preceding '.' to simplify the loop */
			dot = name - 1;

			while (dot && arr)
			{
				namep = dot + 1;
				dot = strchr(namep, '.');
				len = dot ? dot - namep : strlen(namep);
				dict = find_field(arr, namep, len);
				if (dot)
					arr = pdf_dict_gets(dict, "Kids");
			}
		}
	}
	fz_always(ctx)
	{
		fz_free(ctx, name);
	}
	fz_catch(ctx)
	{
		fz_warn(ctx, "doc_getField failed: %s", ctx->error->message);
		dict = NULL;
	}

	return dict ? pdf_jsimp_new_obj(js->imp, js->fieldtype, dict) : NULL;
}

static void declare_dom(pdf_js *js)
{
	pdf_jsimp      *imp       = js->imp;

	/* Create the document type */
	js->doctype = pdf_jsimp_new_type(imp, NULL);
	pdf_jsimp_addmethod(imp, js->doctype, "getField", doc_getField);
	pdf_jsimp_addproperty(imp, js->doctype, "event", doc_getEvent, doc_setEvent);

	/* Create the event type */
	js->eventtype = pdf_jsimp_new_type(imp, NULL);
	pdf_jsimp_addproperty(imp, js->eventtype, "target", event_getTarget, event_setTarget);
	pdf_jsimp_addproperty(imp, js->eventtype, "value", event_getValue, event_setValue);
	pdf_jsimp_addproperty(imp, js->eventtype, "willCommit", event_getWillCommit, event_setWillCommit);
	pdf_jsimp_addproperty(imp, js->eventtype, "rc", event_getRC, event_setRC);

	/* Create the field type */
	js->fieldtype = pdf_jsimp_new_type(imp, NULL);
	pdf_jsimp_addproperty(imp, js->fieldtype, "value", field_getValue, field_setValue);
	pdf_jsimp_addproperty(imp, js->fieldtype, "borderStyle", field_getBorderStyle, field_setBorderStyle);
	pdf_jsimp_addproperty(imp, js->fieldtype, "textColor", field_getTextColor, field_setTextColor);
	pdf_jsimp_addproperty(imp, js->fieldtype, "fillColor", field_getFillColor, field_setFillColor);
	pdf_jsimp_addmethod(imp, js->fieldtype, "buttonSetCaption", field_buttonSetCaption);

	/* Create the document object and tell the engine to use */
	pdf_jsimp_set_global_type(js->imp, js->doctype);
}

static void preload_helpers(pdf_js *js)
{
	/* When testing on the cluster, redefine the Date object
	 * to use a fixed date */
#ifdef CLUSTER
	pdf_jsimp_execute(js->imp,
"var MuPDFOldDate = Date\n"
"Date = function() { return new MuPDFOldDate(1979,5,15); }\n"
	);
#endif

	pdf_jsimp_execute(js->imp,
#include "../generated/js_util.h"
	);
}

pdf_js *pdf_new_js(pdf_document *doc)
{
	fz_context *ctx = doc->ctx;
	pdf_js     *js = NULL;
	pdf_obj    *javascript = NULL;
	char *codebuf = NULL;

	fz_var(js);
	fz_var(javascript);
	fz_var(codebuf);
	fz_try(ctx)
	{
		int len, i;
		pdf_obj *root, *acroform;
		js = fz_malloc_struct(ctx, pdf_js);
		js->doc = doc;

		/* Find the form array */
		root = pdf_dict_gets(doc->trailer, "Root");
		acroform = pdf_dict_gets(root, "AcroForm");
		js->form = pdf_dict_gets(acroform, "Fields");

		/* Initialise the javascript engine, passing the main context
		 * for use in memory allocation and exception handling. Also
		 * pass our js context, for it to pass back to us. */
		js->imp = pdf_new_jsimp(ctx, js);
		declare_dom(js);

		preload_helpers(js);

		javascript = pdf_load_name_tree(doc, "JavaScript");
		len = pdf_dict_len(javascript);

		for (i = 0; i < len; i++)
		{
			pdf_obj *fragment = pdf_dict_get_val(javascript, i);
			pdf_obj *code = pdf_dict_gets(fragment, "JS");

			if (pdf_is_stream(doc, pdf_to_num(code), pdf_to_gen(code)))
			{
				fz_try(ctx)
				{
					codebuf = pdf_to_utf8(doc, code);
					pdf_jsimp_execute(js->imp, codebuf);
				}
				fz_always(ctx)
				{
					fz_free(ctx, codebuf);
					codebuf = NULL;
				}
				fz_catch(ctx)
				{
					fz_warn(ctx, "Warning: %s", ctx->error->message);
				}
			}
		}
	}
	fz_always(ctx)
	{
		pdf_drop_obj(javascript);
	}
	fz_catch(ctx)
	{
		pdf_drop_js(js);
		js = NULL;
	}

	return js;
}

void pdf_drop_js(pdf_js *js)
{
	if (js)
	{
		fz_context *ctx = js->doc->ctx;
		fz_free(ctx, js->event.value);
		pdf_jsimp_drop_type(js->imp, js->fieldtype);
		pdf_jsimp_drop_type(js->imp, js->doctype);
		pdf_drop_jsimp(js->imp);
		fz_free(ctx, js);
	}
}

void pdf_js_setup_event(pdf_js *js, pdf_js_event *e)
{
	if (js)
	{
		fz_context *ctx = js->doc->ctx;
		char *ev = e->value ? e->value : "";
		char *v = fz_strdup(ctx, ev);

		fz_free(ctx, js->event.value);
		js->event.value = v;

		js->event.target = e->target;
		js->event.rc = 1;
	}
}

pdf_js_event *pdf_js_get_event(pdf_js *js)
{
	return js ? &js->event : NULL;
}

void pdf_js_execute(pdf_js *js, char *code)
{
	if (js)
	{
		fz_context *ctx = js->doc->ctx;
		fz_try(ctx)
		{
			pdf_jsimp_execute(js->imp, code);
		}
		fz_catch(ctx)
		{
		}
	}
}

void pdf_js_execute_count(pdf_js *js, char *code, int count)
{
	if (js)
	{
		fz_context *ctx = js->doc->ctx;
		fz_try(ctx)
		{
			pdf_jsimp_execute_count(js->imp, code, count);
		}
		fz_catch(ctx)
		{
		}
	}
}