/**
 * Created by nuintun on 2015/11/24.
 */

'use strict';

module.exports = function (Terminal){
  // CSI s
  // Save cursor (ANSI.SYS).
  Terminal.prototype.saveCursor = function (){
    this.savedX = this.x;
    this.savedY = this.y;
  };

  // CSI u
  // Restore cursor (ANSI.SYS).
  Terminal.prototype.restoreCursor = function (){
    this.x = this.savedX || 0;
    this.y = this.savedY || 0;
  };

  // CSI Ps A
  // Cursor Up Ps Times (default = 1) (CUU).
  Terminal.prototype.cursorUp = function (params){
    var param = params[0];

    if (param < 1) param = 1;

    this.y -= param;

    if (this.y < 0) this.y = 0;
  };

  // CSI Ps B
  // Cursor Down Ps Times (default = 1) (CUD).
  Terminal.prototype.cursorDown = function (params){
    var param = params[0];

    if (param < 1) param = 1;

    this.y += param;

    if (this.y >= this.rows) {
      this.y = this.rows - 1;
    }
  };

  // CSI Ps C
  // Cursor Forward Ps Times (default = 1) (CUF).
  Terminal.prototype.cursorForward = function (params){
    var param = params[0];

    if (param < 1) param = 1;

    this.x += param;

    if (this.x >= this.cols) {
      this.x = this.cols - 1;
    }
  };

  // CSI Ps D
  // Cursor Backward Ps Times (default = 1) (CUB).
  Terminal.prototype.cursorBackward = function (params){
    var param = params[0];

    if (param < 1) param = 1;

    this.x -= param;

    if (this.x < 0) this.x = 0;
  };

  // CSI Ps ; Ps H
  // Cursor Position [row;column] (default = [1,1]) (CUP).
  Terminal.prototype.cursorPos = function (params){
    var row, col;

    row = params[0] - 1;

    if (params.length >= 2) {
      col = params[1] - 1;
    } else {
      col = 0;
    }

    if (row < 0) {
      row = 0;
    } else if (row >= this.rows) {
      row = this.rows - 1;
    }

    if (col < 0) {
      col = 0;
    } else if (col >= this.cols) {
      col = this.cols - 1;
    }

    this.x = col;
    this.y = row;
  };

  // CSI Ps E
  // Cursor Next Line Ps Times (default = 1) (CNL).
  // same as CSI Ps B ?
  Terminal.prototype.cursorNextLine = function (params){
    var param = params[0];

    if (param < 1) param = 1;

    this.y += param;

    if (this.y >= this.rows) {
      this.y = this.rows - 1;
    }

    this.x = 0;
  };

  // CSI Ps F
  // Cursor Preceding Line Ps Times (default = 1) (CNL).
  // reuse CSI Ps A ?
  Terminal.prototype.cursorPrecedingLine = function (params){
    var param = params[0];

    if (param < 1) param = 1;

    this.y -= param;

    if (this.y < 0) this.y = 0;

    this.x = 0;
  };

  // CSI Ps G
  // Cursor Character Absolute [column] (default = [row,1]) (CHA).
  Terminal.prototype.cursorCharAbsolute = function (params){
    var param = params[0];

    if (param < 1) param = 1;

    this.x = param - 1;
  };

  // CSI Ps I
  // Cursor Forward Tabulation Ps tab stops (default = 1) (CHT).
  Terminal.prototype.cursorForwardTab = function (params){
    var param = params[0] || 1;

    while (param--) {
      this.x = this.nextStop();
    }
  };

  // CSI Ps Z Cursor Backward Tabulation Ps tab stops (default = 1) (CBT).
  Terminal.prototype.cursorBackwardTab = function (params){
    var param = params[0] || 1;

    while (param--) {
      this.x = this.prevStop();
    }
  };
};