/*
* This file is part of LibCSS.
* Licensed under the MIT License,
* http://www.opensource.org/licenses/mit-license.php
* Copyright 2009 John-Mark Bell <jmb@netsurf-browser.org>
*/
#include <assert.h>
#include <string.h>
#include "bytecode/bytecode.h"
#include "bytecode/opcodes.h"
#include "parse/properties/properties.h"
#include "parse/properties/utils.h"
/**
* Parse background-position
*
* \param c Parsing context
* \param vector Vector of tokens to process
* \param ctx Pointer to vector iteration context
* \param result Pointer to location to receive resulting style
* \return CSS_OK on success,
* CSS_NOMEM on memory exhaustion,
* CSS_INVALID if the input is not valid
*
* Post condition: \a *ctx is updated with the next token to process
* If the input is invalid, then \a *ctx remains unchanged.
*/
css_error css__parse_background_position(css_language *c,
const parserutils_vector *vector, int *ctx,
css_style *result)
{
int orig_ctx = *ctx;
css_error error;
const css_token *token;
uint8_t flags = 0;
uint16_t value[2] = { 0 };
css_fixed length[2] = { 0 };
uint32_t unit[2] = { 0 };
bool match;
/* [length | percentage | IDENT(left, right, top, bottom, center)]{1,2}
* | IDENT(inherit) */
token = parserutils_vector_peek(vector, *ctx);
if (token == NULL) {
*ctx = orig_ctx;
return CSS_INVALID;
}
if (token->type == CSS_TOKEN_IDENT &&
(lwc_string_caseless_isequal(
token->idata, c->strings[INHERIT],
&match) == lwc_error_ok && match)) {
parserutils_vector_iterate(vector, ctx);
flags = FLAG_INHERIT;
} else {
int i;
for (i = 0; i < 2; i++) {
token = parserutils_vector_peek(vector, *ctx);
if (token == NULL)
break;
if (token->type == CSS_TOKEN_IDENT) {
if ((lwc_string_caseless_isequal(
token->idata, c->strings[LEFT],
&match) == lwc_error_ok &&
match)) {
value[i] =
BACKGROUND_POSITION_HORZ_LEFT;
} else if ((lwc_string_caseless_isequal(
token->idata, c->strings[RIGHT],
&match) == lwc_error_ok &&
match)) {
value[i] =
BACKGROUND_POSITION_HORZ_RIGHT;
} else if ((lwc_string_caseless_isequal(
token->idata, c->strings[TOP],
&match) == lwc_error_ok &&
match)) {
value[i] = BACKGROUND_POSITION_VERT_TOP;
} else if ((lwc_string_caseless_isequal(
token->idata,
c->strings[BOTTOM],
&match) == lwc_error_ok &&
match)) {
value[i] =
BACKGROUND_POSITION_VERT_BOTTOM;
} else if ((lwc_string_caseless_isequal(
token->idata,
c->strings[CENTER],
&match) == lwc_error_ok &&
match)) {
/* We'll fix this up later */
value[i] =
BACKGROUND_POSITION_VERT_CENTER;
} else if (i == 1) {
/* Second pass, so ignore this one */
break;
} else {
/* First pass, so invalid */
*ctx = orig_ctx;
return CSS_INVALID;
}
parserutils_vector_iterate(vector, ctx);
} else if (token->type == CSS_TOKEN_DIMENSION ||
token->type == CSS_TOKEN_NUMBER ||
token->type == CSS_TOKEN_PERCENTAGE) {
error = css__parse_unit_specifier(c, vector, ctx,
UNIT_PX, &length[i], &unit[i]);
if (error != CSS_OK) {
*ctx = orig_ctx;
return error;
}
if (unit[i] & UNIT_ANGLE ||
unit[i] & UNIT_TIME ||
unit[i] & UNIT_FREQ) {
*ctx = orig_ctx;
return CSS_INVALID;
}
/* We'll fix this up later, too */
value[i] = BACKGROUND_POSITION_VERT_SET;
} else {
if (i == 1) {
/* Second pass, so ignore */
break;
} else {
/* First pass, so invalid */
*ctx = orig_ctx;
return CSS_INVALID;
}
}
consumeWhitespace(vector, ctx);
}
/* Now, sort out the mess we've got */
if (i == 1) {
assert(BACKGROUND_POSITION_VERT_CENTER
== BACKGROUND_POSITION_HORZ_CENTER);
/* Only one value, so the other is center */
switch (value[0]) {
case BACKGROUND_POSITION_HORZ_LEFT:
case BACKGROUND_POSITION_HORZ_RIGHT:
case BACKGROUND_POSITION_VERT_CENTER:
case BACKGROUND_POSITION_VERT_TOP:
case BACKGROUND_POSITION_VERT_BOTTOM:
break;
case BACKGROUND_POSITION_VERT_SET:
value[0] = BACKGROUND_POSITION_HORZ_SET;
break;
}
value[1] = BACKGROUND_POSITION_VERT_CENTER;
} else if (value[0] != BACKGROUND_POSITION_VERT_SET &&
value[1] != BACKGROUND_POSITION_VERT_SET) {
/* Two keywords. Verify the axes differ */
if (((value[0] & 0xf) != 0 && (value[1] & 0xf) != 0) ||
((value[0] & 0xf0) != 0 &&
(value[1] & 0xf0) != 0)) {
*ctx = orig_ctx;
return CSS_INVALID;
}
} else {
/* One or two non-keywords. First is horizontal */
if (value[0] == BACKGROUND_POSITION_VERT_SET)
value[0] = BACKGROUND_POSITION_HORZ_SET;
/* Verify the axes differ */
if (((value[0] & 0xf) != 0 && (value[1] & 0xf) != 0) ||
((value[0] & 0xf0) != 0 &&
(value[1] & 0xf0) != 0)) {
*ctx = orig_ctx;
return CSS_INVALID;
}
}
}
error = css__stylesheet_style_appendOPV(result,
CSS_PROP_BACKGROUND_POSITION,
flags,
value[0] | value[1]);
if (error != CSS_OK) {
*ctx = orig_ctx;
return error;
}
if ((flags & FLAG_INHERIT) == false) {
if (value[0] == BACKGROUND_POSITION_HORZ_SET) {
css__stylesheet_style_append(result, length[0]);
css__stylesheet_style_append(result, unit[0]);
}
if (value[1] == BACKGROUND_POSITION_VERT_SET) {
css__stylesheet_style_append(result, length[1]);
css__stylesheet_style_append(result, unit[1]);
}
}
return CSS_OK;
}