/*
 * 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 <string.h>

#include "bytecode/bytecode.h"
#include "bytecode/opcodes.h"
#include "parse/properties/properties.h"
#include "parse/properties/utils.h"

static css_error parse_side(css_language *c,
		const parserutils_vector *vector, int *ctx,
		uint16_t op, css_style **result);

/**
 * Parse bottom
 *
 * \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 parse_bottom(css_language *c, 
		const parserutils_vector *vector, int *ctx, 
		css_style **result)
{
	return parse_side(c, vector, ctx, CSS_PROP_BOTTOM, result);
}

/**
 * Parse left
 *
 * \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 parse_left(css_language *c, 
		const parserutils_vector *vector, int *ctx, 
		css_style **result)
{
	return parse_side(c, vector, ctx, CSS_PROP_LEFT, result);
}

/**
 * Parse right
 *
 * \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 parse_right(css_language *c, 
		const parserutils_vector *vector, int *ctx, 
		css_style **result)
{
	return parse_side(c, vector, ctx, CSS_PROP_RIGHT, result);
}

/**
 * Parse top
 *
 * \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 parse_top(css_language *c, 
		const parserutils_vector *vector, int *ctx, 
		css_style **result)
{
	return parse_side(c, vector, ctx, CSS_PROP_TOP, result);
}

/**
 * Parse 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 parse_position(css_language *c, 
		const parserutils_vector *vector, int *ctx, 
		css_style **result)
{
	int orig_ctx = *ctx;
	css_error error;
	const css_token *ident;
	uint8_t flags = 0;
	uint16_t value = 0;
	uint32_t opv;

	/* IDENT (static, relative, absolute, fixed, inherit) */
	ident = parserutils_vector_iterate(vector, ctx);
	if (ident == NULL || ident->type != CSS_TOKEN_IDENT) {
		*ctx = orig_ctx;
		return CSS_INVALID;
	}

	if (ident->ilower == c->strings[INHERIT]) {
		flags |= FLAG_INHERIT;
	} else if (ident->ilower == c->strings[STATIC]) {
		value = POSITION_STATIC;
	} else if (ident->ilower == c->strings[RELATIVE]) {
		value = POSITION_RELATIVE;
	} else if (ident->ilower == c->strings[ABSOLUTE]) {
		value = POSITION_ABSOLUTE;
	} else if (ident->ilower == c->strings[FIXED]) {
		value = POSITION_FIXED;
	} else {
		*ctx = orig_ctx;
		return CSS_INVALID;
	}

	opv = buildOPV(CSS_PROP_POSITION, flags, value);

	/* Allocate result */
	error = css_stylesheet_style_create(c->sheet, sizeof(opv), result);
	if (error != CSS_OK) {
		*ctx = orig_ctx;
		return error;
	}

	/* Copy the bytecode to it */
	memcpy((*result)->bytecode, &opv, sizeof(opv));

	return CSS_OK;
}

/**
 * Parse clear
 *
 * \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 parse_clear(css_language *c, 
		const parserutils_vector *vector, int *ctx, 
		css_style **result)
{
	int orig_ctx = *ctx;
	css_error error;
	const css_token *ident;
	uint8_t flags = 0;
	uint16_t value = 0;
	uint32_t opv;

	/* IDENT (left, right, both, none, inherit) */
	ident = parserutils_vector_iterate(vector, ctx);
	if (ident == NULL || ident->type != CSS_TOKEN_IDENT) {
		*ctx = orig_ctx;
		return CSS_INVALID;
	}

	if (ident->ilower == c->strings[INHERIT]) {
		flags |= FLAG_INHERIT;
	} else if (ident->ilower == c->strings[RIGHT]) {
		value = CLEAR_RIGHT;
	} else if (ident->ilower == c->strings[LEFT]) {
		value = CLEAR_LEFT;
	} else if (ident->ilower == c->strings[BOTH]) {
		value = CLEAR_BOTH;
	} else if (ident->ilower == c->strings[NONE]) {
		value = CLEAR_NONE;
	} else {
		*ctx = orig_ctx;
		return CSS_INVALID;
	}

	opv = buildOPV(CSS_PROP_CLEAR, flags, value);

	/* Allocate result */
	error = css_stylesheet_style_create(c->sheet, sizeof(opv), result);
	if (error != CSS_OK) {
		*ctx = orig_ctx;
		return error;
	}

	/* Copy the bytecode to it */
	memcpy((*result)->bytecode, &opv, sizeof(opv));

	return CSS_OK;
}

/**
 * Parse float
 *
 * \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 parse_float(css_language *c, 
		const parserutils_vector *vector, int *ctx, 
		css_style **result)
{
	int orig_ctx = *ctx;
	css_error error;
	const css_token *ident;
	uint8_t flags = 0;
	uint16_t value = 0;
	uint32_t opv;

	/* IDENT (left, right, none, inherit) */
	ident = parserutils_vector_iterate(vector, ctx);
	if (ident == NULL || ident->type != CSS_TOKEN_IDENT) {
		*ctx = orig_ctx;
		return CSS_INVALID;
	}

	if (ident->ilower == c->strings[INHERIT]) {
		flags |= FLAG_INHERIT;
	} else if (ident->ilower == c->strings[LEFT]) {
		value = FLOAT_LEFT;
	} else if (ident->ilower == c->strings[RIGHT]) {
		value = FLOAT_RIGHT;
	} else if (ident->ilower == c->strings[NONE]) {
		value = FLOAT_NONE;
	} else {
		*ctx = orig_ctx;
		return CSS_INVALID;
	}

	opv = buildOPV(CSS_PROP_FLOAT, flags, value);

	/* Allocate result */
	error = css_stylesheet_style_create(c->sheet, sizeof(opv), result);
	if (error != CSS_OK) {
		*ctx = orig_ctx;
		return error;
	}

	/* Copy the bytecode to it */
	memcpy((*result)->bytecode, &opv, sizeof(opv));

	return CSS_OK;
}

/**
 * Parse vertical-align
 *
 * \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 parse_vertical_align(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 = 0;
	uint32_t opv;
	css_fixed length = 0;
	uint32_t unit = 0;
	uint32_t required_size;

	/* length | percentage | IDENT(baseline, sub, super, top, text-top,
	 *                             middle, bottom, text-bottom, inherit)
	 */
	token = parserutils_vector_peek(vector, *ctx);
	if (token == NULL) {
		*ctx = orig_ctx;
		return CSS_INVALID;
	}

	if (token->type == CSS_TOKEN_IDENT &&
			token->ilower == c->strings[INHERIT]) {
		parserutils_vector_iterate(vector, ctx);
		flags = FLAG_INHERIT;
	} else if (token->type == CSS_TOKEN_IDENT &&
			token->ilower == c->strings[BASELINE]) {
		parserutils_vector_iterate(vector, ctx);
		value = VERTICAL_ALIGN_BASELINE;
	} else if (token->type == CSS_TOKEN_IDENT &&
			token->ilower == c->strings[SUB]) {
		parserutils_vector_iterate(vector, ctx);
		value = VERTICAL_ALIGN_SUB;
	} else if (token->type == CSS_TOKEN_IDENT &&
			token->ilower == c->strings[SUPER]) {
		parserutils_vector_iterate(vector, ctx);
		value = VERTICAL_ALIGN_SUPER;
	} else if (token->type == CSS_TOKEN_IDENT &&
			token->ilower == c->strings[TOP]) {
		parserutils_vector_iterate(vector, ctx);
		value = VERTICAL_ALIGN_TOP;
	} else if (token->type == CSS_TOKEN_IDENT &&
			token->ilower == c->strings[TEXT_TOP]) {
		parserutils_vector_iterate(vector, ctx);
		value = VERTICAL_ALIGN_TEXT_TOP;
	} else if (token->type == CSS_TOKEN_IDENT &&
			token->ilower == c->strings[MIDDLE]) {
		parserutils_vector_iterate(vector, ctx);
		value = VERTICAL_ALIGN_MIDDLE;
	} else if (token->type == CSS_TOKEN_IDENT &&
			token->ilower == c->strings[BOTTOM]) {
		parserutils_vector_iterate(vector, ctx);
		value = VERTICAL_ALIGN_BOTTOM;
	} else if (token->type == CSS_TOKEN_IDENT &&
			token->ilower == c->strings[TEXT_BOTTOM]) {
		parserutils_vector_iterate(vector, ctx);
		value = VERTICAL_ALIGN_TEXT_BOTTOM;
	} else {
		error = parse_unit_specifier(c, vector, ctx, UNIT_PX,
				&length, &unit);
		if (error != CSS_OK) {
			*ctx = orig_ctx;
			return error;
		}

		if (unit & UNIT_ANGLE || unit & UNIT_TIME || unit & UNIT_FREQ) {
			*ctx = orig_ctx;
			return CSS_INVALID;
		}

		value = VERTICAL_ALIGN_SET;
	}

	opv = buildOPV(CSS_PROP_VERTICAL_ALIGN, flags, value);

	required_size = sizeof(opv);
	if ((flags & FLAG_INHERIT) == false && value == VERTICAL_ALIGN_SET)
		required_size += sizeof(length) + sizeof(unit);

	/* Allocate result */
	error = css_stylesheet_style_create(c->sheet, required_size, result);
	if (error != CSS_OK) {
		*ctx = orig_ctx;
		return error;
	}

	/* Copy the bytecode to it */
	memcpy((*result)->bytecode, &opv, sizeof(opv));
	if ((flags & FLAG_INHERIT) == false && value == VERTICAL_ALIGN_SET) {
		memcpy(((uint8_t *) (*result)->bytecode) + sizeof(opv),
				&length, sizeof(length));
		memcpy(((uint8_t *) (*result)->bytecode) + sizeof(opv) +
				sizeof(length), &unit, sizeof(unit));
	}

	return CSS_OK;
}

/**
 * Parse {top,right,bottom,left}
 *
 * \param c       Parsing context
 * \param vector  Vector of tokens to process
 * \param ctx     Pointer to vector iteration context
 * \param op      Opcode to parse for
 * \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 parse_side(css_language *c,
		const parserutils_vector *vector, int *ctx,
		uint16_t op, css_style **result)
{
	int orig_ctx = *ctx;
	css_error error;
	const css_token *token;
	uint8_t flags = 0;
	uint16_t value = 0;
	uint32_t opv;
	css_fixed length = 0;
	uint32_t unit = 0;
	uint32_t required_size;

	/* length | percentage | IDENT(auto, inherit) */
	token = parserutils_vector_peek(vector, *ctx);
	if (token == NULL) {
		*ctx = orig_ctx;
		return CSS_INVALID;
	}

	if (token->type == CSS_TOKEN_IDENT &&
			token->ilower == c->strings[INHERIT]) {
		parserutils_vector_iterate(vector, ctx);
		flags = FLAG_INHERIT;
	} else if (token->type == CSS_TOKEN_IDENT &&
			token->ilower == c->strings[AUTO]) {
		parserutils_vector_iterate(vector, ctx);
		value = BOTTOM_AUTO;
	} else {
		error = parse_unit_specifier(c, vector, ctx, UNIT_PX,
				&length, &unit);
		if (error != CSS_OK) {
			*ctx = orig_ctx;
			return error;
		}

		if (unit & UNIT_ANGLE || unit & UNIT_TIME || unit & UNIT_FREQ) {
			*ctx = orig_ctx;
			return CSS_INVALID;
		}

		value = BOTTOM_SET;
	}

	opv = buildOPV(op, flags, value);

	required_size = sizeof(opv);
	if ((flags & FLAG_INHERIT) == false && value == BOTTOM_SET)
		required_size += sizeof(length) + sizeof(unit);

	/* Allocate result */
	error = css_stylesheet_style_create(c->sheet, required_size, result);
	if (error != CSS_OK) {
		*ctx = orig_ctx;
		return error;
	}

	/* Copy the bytecode to it */
	memcpy((*result)->bytecode, &opv, sizeof(opv));
	if ((flags & FLAG_INHERIT) == false && value == BOTTOM_SET) {
		memcpy(((uint8_t *) (*result)->bytecode) + sizeof(opv),
				&length, sizeof(length));
		memcpy(((uint8_t *) (*result)->bytecode) + sizeof(opv) +
				sizeof(length), &unit, sizeof(unit));
	}

	return CSS_OK;
}