<?php

namespace VariableAnalysis\Lib;

use VariableAnalysis\Lib\ScopeType;

/**
 * Holds details of a variable within a scope.
 */
class VariableInfo
{
	/**
	 * @var string
	 */
	public $name;

	/**
	 * What scope the variable has: local, param, static, global, bound
	 *
	 * @var ScopeType::PARAM|ScopeType::BOUND|ScopeType::LOCAL|ScopeType::GLOBALSCOPE|ScopeType::STATICSCOPE|null
	 */
	public $scopeType;

	/**
	 * @var string|null
	 */
	public $typeHint;

	/**
	 * @var int|null
	 */
	public $referencedVariableScope;

	/**
	 * True if the variable is a reference but one created at runtime
	 *
	 * @var bool
	 */
	public $isDynamicReference = false;

	/**
	 * Stack pointer of first declaration
	 *
	 * Declaration is when a variable is created but has no value assigned.
	 *
	 * Assignment by reference is also a declaration and not an initialization.
	 *
	 * @var int|null
	 */
	public $firstDeclared;

	/**
	 * Stack pointer of first initialization
	 *
	 * @var int|null
	 */
	public $firstInitialized;

	/**
	 * Stack pointer of first read
	 *
	 * @var int|null
	 */
	public $firstRead;

	/**
	 * Stack pointers of all assignments
	 *
	 * This includes both declarations and initializations and may contain
	 * duplicates!
	 *
	 * @var int[]
	 */
	public $allAssignments = [];

	/**
	 * @var bool
	 */
	public $ignoreUnused = false;

	/**
	 * @var bool
	 */
	public $ignoreUndefined = false;

	/**
	 * @var bool
	 */
	public $isForeachLoopAssociativeValue = false;

	/**
	 * @var array<ScopeType::PARAM|ScopeType::BOUND|ScopeType::LOCAL|ScopeType::GLOBALSCOPE|ScopeType::STATICSCOPE, string>
	 */
	public static $scopeTypeDescriptions = [
		ScopeType::LOCAL  => 'variable',
		ScopeType::PARAM  => 'function parameter',
		ScopeType::STATICSCOPE => 'static variable',
		ScopeType::GLOBALSCOPE => 'global variable',
		ScopeType::BOUND  => 'bound variable',
	];

	/**
	 * @param string $varName
	 */
	public function __construct($varName)
	{
		$this->name = $varName;
	}
}