/**
 *  LogarithmPlotter - 2D plotter software to make BODE plots, sequences and distribution functions.
 *  Copyright (C) 2021-2024  Ad5001
 * 
 *  This program is free software: you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation, either version 3 of the License, or
 *  (at your option) any later version.
 * 
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 * 
 *  You should have received a copy of the GNU General Public License
 *  along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */

.pragma library

.import "polyfill.js" as Polyfill


const CONSTANTS = {
    "π": Math.PI,
    "pi": Math.PI,
    "inf": Infinity,
    "infinity": Infinity,
    "∞": Infinity,
    "e": Math.E
};
const CONSTANTS_LIST = Object.keys(CONSTANTS);

const FUNCTIONS = {
    // The functions commented are the one either not implemented 
    // in the parser, or not to be used for autocompletion.
    // Unary operators
    //'+': Number,
    //'-': (x) => -x,
    //'!'
    // Other operations
    'length': (s) => Array.isArray(s) ? s.length : String(s).length,
    // Boolean functions
    'not': (x) => !x,
    // Math functions
    'abs': Math.abs,
    'acos': Math.acos,
    'acosh': Math.acosh,
    'asin': Math.asin,
    'asinh': Math.asinh,
    'atan': Math.atan,
    'atan2': Math.atan2,
    'atanh': Math.atanh,
    'cbrt': Math.cbrt,
    'ceil': Math.ceil,
    //'clz32': Math.clz32,
    'cos': Math.cos,
    'cosh': Math.cosh,
    'exp': Math.exp,
    'expm1': Math.expm1,
    'floor': Math.floor,
    //'fround': Math.fround,
    'hypot': Math.hypot,
    //'imul': Math.imul,
    'lg': Math.log10,
    'ln': Math.log,
    'log': Math.log,
    'log10': Math.log10,
    'log1p': Math.log1p,
    'log2': Math.log2,
    'max': Math.max,
    'min': Math.min,
    'pow': Math.log2,
    'random': Math.random,
    'round': Math.round,
    'sign': Math.sign,
    'sin': Math.sin,
    'sinh': Math.sinh,
    'sqrt': Math.sqrt,
    'tan': Math.tan,
    'tanh': Math.tanh,
    'trunc': Math.trunc,
    // Functions in expr-eval, ported here.
    'fac': Polyfill.factorial,
    'gamma': Polyfill.gamma,
    'Γ': Polyfill.gamma,
    'roundTo': (x, exp) => Number(x).toFixed(exp),
    // 'map': Polyfill.arrayMap,
    // 'fold': Polyfill.arrayFold,
    // 'filter': Polyfill.arrayFilter,
    // 'indexOf': Polyfill.indexOf,
    // 'join': Polyfill.arrayJoin,
    // Integral & derivative (only here for autocomplete).
    'integral': () => 0, // TODO: Implement
    'derivative': () => 0,
}
const FUNCTIONS_LIST = Object.keys(FUNCTIONS);

class P {
    // Parameter class.
    constructor(type, name = '', optional = false, multipleAllowed = false) {
        this.name = name
        this.type = type
        this.optional = optional
        this.multipleAllowed = multipleAllowed
    }
    
    toString() {
        let base_string = this.type
        if(this.name != '')
            base_string = `${this.name}: ${base_string}`
        if(this.multipleAllowed)
            base_string += '...'
        if(!this.optional)
            base_string = `<${base_string}>`
        else
            base_string = `[${base_string}]`
        return base_string
    }
}

let string = new P('string')
let bool = new P('bool')
let number = new P('number')
let array = new P('array')

const FUNCTIONS_USAGE = {
    'length': [string],
    'not': [bool],
    // Math functions
    'abs': [number],
    'acos': [number],
    'acosh': [number],
    'asin': [number],
    'asinh': [number],
    'atan': [number],
    'atan2': [number],
    'atanh': [number],
    'cbrt': [number],
    'ceil': [number],
    //'clz32': [number],
    'cos': [number],
    'cosh': [number],
    'exp': [number],
    'expm1': [number],
    'floor': [number],
    //'fround': [number],
    'hypot': [number],
    //'imul': [number],
    'lg': [number],
    'ln': [number],
    'log': [number],
    'log10': [number],
    'log1p': [number],
    'log2': [number],
    'max': [number, number, new P('numbers', '', true, true)],
    'min': [number, number, new P('numbers', '', true, true)],
    'pow': [number, new P('number', 'exp')],
    'random': [number, number],
    'round': [number],
    'sign': [number],
    'sin': [number],
    'sinh': [number],
    'sqrt': [number],
    'tan': [number],
    'tanh': [number],
    'trunc': [number],
    // Functions in expr-eval, ported here.
    'fac': [number],
    'gamma': [number],
    'Γ': [number],
    'roundTo': [number, new P('number')],
    // Function manipulation
    'derivative': [new P('f'), new P('string', 'var', true), number],
    'integral': [new P('from'), new P('to'), new P('f'), new P('string', 'var', true)],
}