import attributes from './attributes'

function path ()
{
  this.render = true;
  this.attributes = new attributes();

  /** Adds a move operation to Point to */
  this.prototype.move = function (to)
  {
    this.ops.push({type: "move", to});

    return this;
  }

  /** Adds a line operation to Point to */
  this.prototype.line = function (to)
  {
    this.ops.push({type: "line", to});

    return this;
  }

  /** Adds a line operation to Point to */
  this.prototype.curve = function (cp1, cp2, to)
  {
    this.ops.push({type: "curve", cp1, cp2, to});

    return this;
  }

  /** Adds a close operation */
  this.prototype.close = function ()
  {
    this.ops.push({type: "close"});

    return this;
  }

  /** Adds an attribute. This is here to make this call chainable in assignment */
  this.prototype.attr = function (name, value)
  {
    this.attributes.add(name, value);

    return this;
  }

  /** Returns SVG pathstring for this path */
  this.prototype.asPathstring = function ()
  {
    let d = '';
    for(let op of this.ops) {
      switch (op.type) {
        case 'move':
          d += `M ${op.to.x},${op.to.y}`;
          break;
        case 'line':
          d += ` L ${op.to.x},${op.to.y}`;
          break;
        case 'curve':
          d += ` C ${op.cp1.x},${op.cp1.y} ${op.cp2.x},${op.cp2.y} ${op.to.x},${op.to.y}`;
          break;
        case 'close':
          d += ' z';
          break;
        default:
          throw `${op.type} is not a valid path command`;
          break;
      }
    }

    return d;
  }
}

export default path;