// Type definitions for algebra.js 0.2
// Project: http://algebra.js.org
// Definitions by: Federico Caselli <https://github.com/CaselIT>
// Definitions: https://github.com/DefinitelyTyped/DefinitelyTyped
// TypeScript Version: 2.2

declare class Term {
  coefficients: algebra.js.Fraction[];
  variables: Variable[];
  coefficient(): algebra.js.Fraction;
  toString(): string;
}

declare class Variable {
  variable: string;
  toString(): string;
}

type Union = string | number | algebra.js.Fraction | Term;

declare namespace algebra.js {
  function parse(input: string): Equation | Expression;
  function toTex(input: Fraction | Expression | Equation | object | Array<Fraction | object>): string;

  class Equation {
    lhs: Expression;
    rhs: Expression;
    constructor(lhs: Expression, rhs: Expression | Fraction | number)
    solveFor(variable: string): Fraction | Fraction[] | number[];
    toString(): string;
  }

  class Expression {
    constants: Fraction[];
    terms: Term[];
    constructor(variable: Union | undefined)
    add(other: Union | Expression, simplify?: boolean): Expression;
    divide(other: Fraction | number, simplify?: boolean): Expression;
    eval(p: object, simplify?: boolean): Expression;
    multiply(other: Union | Expression, simplify?: boolean): Expression;
    pow(p: number, simplify?: boolean): Expression;
    constant(): Fraction;
    simplify(): Expression;
    subtract(other: Union | Expression, simplify?: boolean): Expression;
    summation(variable: string, lower: number, upper: number, simplify?: boolean): Expression;
    toString(): string;
  }

  class Fraction {
    denom: number;
    numer: number;
    constructor(num: number, denom: number)
    abs(): Fraction;
    add(other: Fraction | number, simplify?: boolean): Fraction;
    divide(other: Fraction | number, simplify?: boolean): Fraction;
    multiply(other: Fraction | number, simplify?: boolean): Fraction;
    subtract(other: Fraction | number, simplify?: boolean): Fraction;
    toString(): string;
    valueOf(): number;
  }
}
export = algebra.js;