import { Type } from '../../types';
import { Value } from '../base';
import { Metadata } from '../constants';
import * as instructions from './';

export abstract class Instruction extends Value {
  public readonly metadata: Map<string, Metadata> = new Map();

  constructor(ty: Type, public readonly opcode: string,
              protected readonly operands: Value[]) {
    super(ty);
  }

  public isExtractValue(): boolean {
    return this instanceof instructions.ExtractValue;
  }

  public isInsertValue(): boolean {
    return this instanceof instructions.InsertValue;
  }

  public isGetElementPtr(): boolean {
    return this instanceof instructions.GetElementPtr;
  }

  public isUnreachable(): boolean {
    return this instanceof instructions.Unreachable;
  }

  public *[Symbol.iterator](): Iterator<Value> {
    yield* this.operands;
  }

  public toString(): string {
    const operands = this.operands.map((op) => {
      if (op instanceof Instruction) {
        return `[instr opcode=${op.opcode}]`;
      }
      return op.toString();
    });
    return `[instr opcode=${this.opcode} operands={${operands.join(', ')}}]`;
  }
}