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/*
* This file is part of LibCSS.
* Licensed under the MIT License,
* http://www.opensource.org/licenses/mit-license.php
* Copyright 2024 Daniel Silverstone <dsilvers@netsurf-browser.org>
*/
#ifndef css_select_calc_h_
#define css_select_calc_h_
#include <stdint.h>
#include "bytecode/bytecode.h"
#include "libcss/errors.h"
#include "libcss/unit.h"
typedef struct {
unit unit;
css_fixed value;
} css_calculator_stack_entry;
typedef struct {
uint32_t refcount;
css_calculator_stack_entry *stack;
size_t stack_alloc;
size_t stack_ptr;
#ifndef NDEBUG
lwc_string *canary;
#endif
} css_calculator;
/**
* Create a new CSS calculator
*
* This creates a new CSS calculator with a reference count of one.
*
* The caller is responsible for calling \ref css_calculator_unref
* when it is done with this calculator.
*
* \param out The created calculator in saved here
* \return CSS_OK if no problems were encountered, likely CSS_NOMEM if there
* were
*/
css_error css_calculator_create(css_calculator **out);
/**
* Add a ref to a CSS calculator
*
* If you are storing a calculator in more than one place you should ref
* it when storing it into a new place. You will neeed to call \ref
* css_calculator_unref to match any call to this.
*
* \param calc The calculator to add a reference to
* \return The same calculator pointer for ease of use
*/
css_calculator *css_calculator_ref(css_calculator *calc);
/**
* Unref a CSS calculator
*
* Every call to \ref css_calculator_create or \ref css_calculator_ref must be
* matched with a call to this function. When the last ref is removed then
* the underlying calculator is freed.
*
* \param calc The calculator to unref
*/
void css_calculator_unref(css_calculator *calc);
/**
* Perform a calculation
*
* To resolve the value of a calc() property, call this function. This will
* interpret the bytecode in the given expression, with the given display
* context and available space, and will fill out the computed unit and value.
*
* \param calc The calculator to use
* \param unit_ctx The display context for resolving units
* \param available The available space (for percentages)
* \param style The style from which the expression was derived
* \param expr The expression to compute
* \param unit_out The computed unit is placed here
* \param value_out The computed value is placed here
* \return CSS_OK if computation succeeded, otherwise likely CSS_INVALID or
* CSS_NOMEM
*/
css_error css_calculator_calculate(css_calculator *calc,
const css_unit_ctx *unit_ctx,
int32_t available, lwc_string *expr,
const css_computed_style *style,
css_unit *unit_out, css_fixed *value_out);
#endif /* css_select_calc_h_ */
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