import { isAccessorNode, isIndexNode, isNode, isSymbolNode } from '../../utils/is.js'

import { getSafeProperty, setSafeProperty } from '../../utils/customs.js'

import { factory } from '../../utils/factory.js'

import { accessFactory } from './utils/access.js'

import { assignFactory } from './utils/assign.js'

import { getPrecedence } from '../operators.js'

const name = 'AssignmentNode'

const dependencies = [

'subset',

'?matrix', // FIXME: should not be needed at all, should be handled by subset

'Node'

]

export const createAssignmentNode = /* #__PURE__ */ factory(name, dependencies, ({ subset, matrix, Node }) => {

const access = accessFactory({ subset })

const assign = assignFactory({ subset, matrix })

/*

* Is parenthesis needed?

* @param {node} node

* @param {string} [parenthesis='keep']

* @param {string} implicit

* @private

*/

function needParenthesis (node, parenthesis, implicit) {

if (!parenthesis) {

parenthesis = 'keep'

}

const precedence = getPrecedence(node, parenthesis, implicit)

const exprPrecedence = getPrecedence(node.value, parenthesis, implicit)

return (parenthesis === 'all') ||

((exprPrecedence !== null) && (exprPrecedence <= precedence))

}

class AssignmentNode extends Node {

/**

* @constructor AssignmentNode

* @extends {Node}

*

* Define a symbol, like `a=3.2`, update a property like `a.b=3.2`, or

* replace a subset of a matrix like `A[2,2]=42`.

*

* Syntax:

*

* new AssignmentNode(symbol, value)

* new AssignmentNode(object, index, value)

*

* Usage:

*

* new AssignmentNode(new SymbolNode('a'), new ConstantNode(2)) // a=2

* new AssignmentNode(new SymbolNode('a'),

* new IndexNode('b'),

* new ConstantNode(2)) // a.b=2

* new AssignmentNode(new SymbolNode('a'),

* new IndexNode(1, 2),

* new ConstantNode(3)) // a[1,2]=3

*

* @param {SymbolNode | AccessorNode} object

* Object on which to assign a value

* @param {IndexNode} [index=null]

* Index, property name or matrix index. Optional. If not provided

* and `object` is a SymbolNode, the property is assigned to the

* global scope.

* @param {Node} value

* The value to be assigned

*/

constructor (object, index, value) {

super()

this.object = object

this.index = value ? index : null

this.value = value || index

// validate input

if (!isSymbolNode(object) && !isAccessorNode(object)) {

throw new TypeError('SymbolNode or AccessorNode expected as "object"')

}

if (isSymbolNode(object) && object.name === 'end') {

throw new Error('Cannot assign to symbol "end"')

}

if (this.index && !isIndexNode(this.index)) { // index is optional

throw new TypeError('IndexNode expected as "index"')

}

if (!isNode(this.value)) {

throw new TypeError('Node expected as "value"')

}

}

// class name for typing purposes:

static name = name

// readonly property name

get name () {

if (this.index) {

return (this.index.isObjectProperty())

? this.index.getObjectProperty()

: ''

} else {

return this.object.name || ''

}

}

get type () { return name }

get isAssignmentNode () { return true }

/**

* Compile a node into a JavaScript function.

* This basically pre-calculates as much as possible and only leaves open

* calculations which depend on a dynamic scope with variables.

* @param {Object} math Math.js namespace with functions and constants.

* @param {Object} argNames An object with argument names as key and `true`

* as value. Used in the SymbolNode to optimize

* for arguments from user assigned functions

* (see FunctionAssignmentNode) or special symbols

* like `end` (see IndexNode).

* @return {function} Returns a function which can be called like:

* evalNode(scope: Object, args: Object, context: *)

*/

_compile (math, argNames) {

const evalObject = this.object._compile(math, argNames)

const evalIndex = this.index ? this.index._compile(math, argNames) : null

const evalValue = this.value._compile(math, argNames)

const name = this.object.name

if (!this.index) {

// apply a variable to the scope, for example `a=2`

if (!isSymbolNode(this.object)) {

throw new TypeError('SymbolNode expected as object')

}

return function evalAssignmentNode (scope, args, context) {

const value = evalValue(scope, args, context)

scope.set(name, value)

return value

}

} else if (this.index.isObjectProperty()) {

// apply an object property for example `a.b=2`

const prop = this.index.getObjectProperty()

return function evalAssignmentNode (scope, args, context) {

const object = evalObject(scope, args, context)

const value = evalValue(scope, args, context)

setSafeProperty(object, prop, value)

return value

}

} else if (isSymbolNode(this.object)) {

// update a matrix subset, for example `a[2]=3`

return function evalAssignmentNode (scope, args, context) {

const childObject = evalObject(scope, args, context)

const value = evalValue(scope, args, context)

// Important: we pass childObject instead of context:

const index = evalIndex(scope, args, childObject)

scope.set(name, assign(childObject, index, value))

return value

}

} else { // isAccessorNode(node.object) === true

// update a matrix subset, for example `a.b[2]=3`

// we will not use the compile function of the AccessorNode, but

// compile it ourselves here as we need the parent object of the

// AccessorNode:

// wee need to apply the updated object to parent object

const evalParentObject = this.object.object._compile(math, argNames)

if (this.object.index.isObjectProperty()) {

const parentProp = this.object.index.getObjectProperty()

return function evalAssignmentNode (scope, args, context) {

const parent = evalParentObject(scope, args, context)

const childObject = getSafeProperty(parent, parentProp)

// Important: we pass childObject instead of context:

const index = evalIndex(scope, args, childObject)

const value = evalValue(scope, args, context)

setSafeProperty(

parent, parentProp, assign(childObject, index, value))

return value

}

} else {

// if some parameters use the 'end' parameter, we need to calculate

// the size

const evalParentIndex = this.object.index._compile(math, argNames)

return function evalAssignmentNode (scope, args, context) {

const parent = evalParentObject(scope, args, context)

// Important: we pass parent instead of context:

const parentIndex = evalParentIndex(scope, args, parent)

const childObject = access(parent, parentIndex)

// Important: we pass childObject instead of context

const index = evalIndex(scope, args, childObject)

const value = evalValue(scope, args, context)

assign(parent, parentIndex, assign(childObject, index, value))

return value

}

}

}

}

/**

* Execute a callback for each of the child nodes of this node

* @param {function(child: Node, path: string, parent: Node)} callback

*/

forEach (callback) {

callback(this.object, 'object', this)

if (this.index) {

callback(this.index, 'index', this)

}

callback(this.value, 'value', this)

}

/**

* Create a new AssignmentNode whose children are the results of calling

* the provided callback function for each child of the original node.

* @param {function(child: Node, path: string, parent: Node): Node} callback

* @returns {AssignmentNode} Returns a transformed copy of the node

*/

map (callback) {

const object = this._ifNode(callback(this.object, 'object', this))

const index = this.index

? this._ifNode(callback(this.index, 'index', this))

: null

const value = this._ifNode(callback(this.value, 'value', this))

return new AssignmentNode(object, index, value)

}

/**

* Create a clone of this node, a shallow copy

* @return {AssignmentNode}

*/

clone () {

return new AssignmentNode(this.object, this.index, this.value)

}

/**

* Get string representation

* @param {Object} options

* @return {string}

*/

_toString (options) {

const object = this.object.toString(options)

const index = this.index ? this.index.toString(options) : ''

let value = this.value.toString(options)

if (needParenthesis(

this, options && options.parenthesis, options && options.implicit)) {

value = '(' + value + ')'

}

return object + index + ' = ' + value

}

/**

* Get a JSON representation of the node

* @returns {Object}

*/

toJSON () {

return {

mathjs: name,

object: this.object,

index: this.index,

value: this.value

}

}

/**

* Instantiate an AssignmentNode from its JSON representation

* @param {Object} json

* An object structured like

* `{"mathjs": "AssignmentNode", object: ..., index: ..., value: ...}`,

* where mathjs is optional

* @returns {AssignmentNode}

*/

static fromJSON (json) {

return new AssignmentNode(json.object, json.index, json.value)

}

/**

* Get HTML representation

* @param {Object} options

* @return {string}

*/

toHTML (options) {

const object = this.object.toHTML(options)

const index = this.index ? this.index.toHTML(options) : ''

let value = this.value.toHTML(options)

if (needParenthesis(

this, options && options.parenthesis, options && options.implicit)) {

value = '<span class="math-paranthesis math-round-parenthesis">(</span>' +

value +

'<span class="math-paranthesis math-round-parenthesis">)</span>'

}

return object + index +

'<span class="math-operator math-assignment-operator ' +

'math-variable-assignment-operator math-binary-operator">=</span>' +

value

}

/**

* Get LaTeX representation

* @param {Object} options

* @return {string}

*/

_toTex (options) {

const object = this.object.toTex(options)

const index = this.index ? this.index.toTex(options) : ''

let value = this.value.toTex(options)

if (needParenthesis(

this, options && options.parenthesis, options && options.implicit)) {

value = `\\left(${value}\\right)`

}

return object + index + ':=' + value

}

}

return AssignmentNode

}, { isClass: true, isNode: true })