<?php
/** DomFramework
  * @package domframework
  * @author Dominique Fournier <dominique@fournier38.fr>
  */

/** Allow to manage a linux Console to have a minimal but working text interface
  * When using this class, you must use the $console::echo method and not
  * display directely on screen
  * Like readline, but all in PHP
  * Manage the historical of the provided commands
  * Allow the user to use arrow keys and the shortcuts Ctrl+arrow, Ctrl+L,
  * Ctrl+U, Ctrl+W
  * To not allow the stop of the program by Ctrl+C, you can add
  *    exec ("stty intr ^J");
  */
class console
{
  // PROPERTIES
  //  {{{
private $usleep = 0;
  /** Save the initial stty value
    */
  private $initSttyState;

  /** Line Content
    */
  private $lineContent = "";

  /** If true, display each char the user has pressed (echo mode)
    */
  private $echoMode = true;

  /** List of non printable chars in decimal. The non printable chars are not
    * displayed but are correctely captured
    */
  private $nonWriteableChar = array (1, 2, 3, 4, 6, 8, 9, 16, 18,
                                     20, 21, 22, 23, 24, 25, 27,
                                     127);
  /* The history list in an array
   */
  private $history = array ();

  /** The history max size in entries
    */
  private $historyMaxSize = 1000;

  /** Set the completion keys. Not set by default
    */
  private $completionKeys = false;

  /** Set the function called when the completion char is called
    */
  private $completionFunction = array ();

  /** Set the width of the terminal in chars
    */
  private $termWidth;

  /** Store the last cursor position in the last readline
    */
  private $cursorPos = 1;
  // }}}

  /** The constructor init the console.
    * Check if we have the rights to execute, if wa have in cli...
    */
  public function __construct ()
  // {{{
  {
    if (! function_exists ("exec"))
      throw $this->ConsoleException ("No exec support in PHP");
    $this->initSttyState = exec ("stty -g");
    // Set the terminal to return the value each time a key is pressed.
    // Do not display anything, so we don't see the characters when the user is
    // deleting.
    // 'intr ^J' allow to redefine the interruption from Ctrl+C to Ctrl+J. It
    // allow to manage the Ctrl+C key to clean the entry
    exec ("stty -echo -icanon min 1 time 0");
    $this->updateTerminalSize ();
  }
  //  }}}

  /** Update the terminal size
    */
  public function updateTerminalSize ()
  // {{{
  {
    $termSize = exec ("stty size", $null, $rc);
    if ($rc === 0)
    {
      list ($termHeight, $termWidth) = explode (" ", $termSize);
      if (is_null ($termWidth) || is_bool ($termWidth))
        $this->termWidth = 80;
      else
        $this->termWidth = intval ($termWidth);
    }
    else
      $this->termWidth = 80;
  }
  // }}}

  /** The destructor return the terminal to initial state
    */
  public function __destruct ()
  // {{{
  {
    exec ("stty $this->initSttyState");
  }
  // }}}

  /** Each time a key is pressed by the user, display the value on screen (echo)
    */
  public function setEcho ()
  // {{{
  {
    $this->echoMode = true;
  }
  // }}}

  /** Each time a key is pressed by the user, DO NOT display the value on screen
    * (echo disabled)
    */
  public function unsetEcho ()
  // {{{
  {
    $this->echoMode = false;
  }
  // }}}

  /** Display a text on screen. Must be used before "readline" method because
    * the provided message will not be deleted by readline process.
    * @param string $message The message to display
    */
  public function echo ($message)
  // {{{
  {
    echo $message;
    $this->lineContent .= $message;
  }
  // }}}

  /** Wait one valid character from the user.
    * The non printable chars are not displayed, nor returned
    * The ESC Sequences are skipped
    * @return the pressed char
    */
  public function getc ()
  // {{{
  {
    $char = $this->getKey ();
    while (in_array (ord ($char), $this->nonWriteableChar))
      $char = $this->getKey ();
    return $char;
  }
   // }}}

  /** Wait one key pressed by the user. If the key pressed is an ESC sequence,
    * return this sequence
    * The non printable chars are not displayed, but are correctely returned
    * The UTF8 chars are return as multiple length chars
    * @return the pressed char
    */
  public function getKey ()
  // {{{
  {
    $char = fgetc (STDIN);
    if ($char === chr (27))
    {
      $sequence = $char;
      $char2 = fgetc (STDIN);
      if (ord ($char2) === 27)
      {
        // Sequence of ESC ESC
      }
      elseif (ord ($char2) === 79)
      {
        // Start an ESC SS3 sequence
        // Like F2 Key
        $sequence .= $char2;
        $char = fgetc (STDIN);
        $sequence .= $char;
      }
      elseif (ord ($char2) === 91)
      {
        // Start an ESC CSI sequence. Do not display it, just return it.
        // The ESC squences are used to communicate the cursor keys, associated
        // with the Ctrl key, by example
        // ESC [ is followed by any number (including none) of "parameter bytes"
        // in the range 0x30–0x3F (ASCII 0–9:;<=>?), then by any number of
        // "intermediate bytes" in the range 0x20–0x2F (ASCII space and
        // !"#$%&'()*+,-./), then finally by a single "final byte" in the range
        // 0x40–0x7E (ASCII @A–Z[\]^_`a–z{|}~).[14]:5.4
        $sequence .= $char2;
        $char = fgetc (STDIN);
        while (ord ($char) < 64 || ord ($char) > 126)
        {
          $sequence .= $char;
          $char = fgetc (STDIN);
        }
        $sequence .= $char;
      }
      else
      {
        $this->consoleException ("Invalid ESC seq : ".ord($char2));
      }
      return $sequence;
    }

    // UTF Sequence :
    // - char1 < 128 : One char (like ascii)
    // - char1 >= 194 && char1 <= 223 : Two chars
    // - char1 >= 224 && char1 <= 239 : Three chars
    // - char1 >= 240 && char1 <= 244 : Four chars
    if (ord ($char) < 128)
    {
      // One Char like ascii
    }
    elseif (ord ($char) >= 194 && ord ($char) <= 223)
    {
      // Two chars
      $char .= fgetc (STDIN);
    }
    elseif (ord ($char) >= 224 && ord ($char) <= 239)
    {
      // Three chars
      $char .= fgetc (STDIN).fgetc (STDIN);
    }
    elseif (ord ($char) >= 240 && ord ($char) <= 244)
    {
      // Four chars
      $char .= fgetc (STDIN).fgetc (STDIN).fgetc (STDIN);
    }
    if ($this->echoMode && ! in_array (ord ($char), $this->nonWriteableChar))
      echo $char;
    return $char;
  }
  // }}}

  /** Get the line of characters pressed by the user and return the result.
    * Stop when the user valid by \n.
    * Manage correctely the backspace, the Ctrl+W to remove word...
    * @param string $propo Preset the text for the user
    * @param bool|string $stopperChar The chars to stop the analysis and return
    * the result
    * @return The typed string
    */
  public function readline ($propo = "", $stopperChar = false)
  // {{{
  {
    // Gets can not delete chars before the call. Keep the prompt (if exists)
    if (! is_string ($propo))
      $this->consoleException ("Invalid proposition provided to readline");
    $prompt = $this->lineContent;
    $minLength = mb_strlen ($this->lineContent) + 1;
    // Manage the history and a temporary buffer if the user has already type
    // something before calling the history
    $historyTmp = "";
    $historyPos = count ($this->history);
    $string = $propo;
    echo $string;
    $this->lineContent = $prompt.$string;
    // The cursor position from last char of line.
    $cursorPos = mb_strlen ($this->lineContent) + 1;
    while (1)
    {
      $char = $this->getKey ();
      if ($stopperChar === false && $char === "\n")
      {
        // End of process without stopperChars
        $this->lineContent = "";
        break;
      }
      if ($stopperChar !== false &&
          in_array ($char, $this->mb_str_split ($stopperChar)))
      {
        // End of process with stopperChars
        $this->lineContent = "";
        break;
      }
      if ($this->completionKeys !== false &&
          in_array ($char, $this->mb_str_split ($this->completionKeys)))
      // Manage autocompletion
      // {{{
      {
        $completeArr = call_user_func ($this->completionFunction, $string);
        $isAssoc = is_array ($completeArr) &&
          array_diff_key ($completeArr, array_keys (array_keys ($completeArr)));
        if (count ($completeArr) === 1)
        {
          if (substr ($string, -1) !== " ")
          {
            // Continuous word is unique : replace the last word by the proposal
            $pos = mb_strrpos ($string, " ");
            if ($pos === false)
              $string = "";
            else
            {
              $string = mb_substr ($string, 0, $pos +1);
            }
          }
          else
          {
            // Next word is unique : add this to the string
          }
          if ($isAssoc)
            $string .= key ($completeArr);
          else
            $string .= reset ($completeArr);
        }
        else
        {
          // Multiple answers : display them
          if ($isAssoc)
          {
            // In associative array, the key is the possible answer to
            // autocompletion, and the value is the helper message
            // Get the largest key length to make a beautiful alignment
            $maxlen = 0;
            foreach ($completeArr as $key => $val)
              $maxlen = max ($maxlen, mb_strlen ($key));
            $maxlen = $maxlen + 5;
            echo "\n";
            foreach ($completeArr as $key => $val)
              printf ("%-${maxlen}s %s\n", $key, $val);
          }
          else
          {
            echo "\n".implode ("\n", $completeArr)."\n";
          }
        }
        $cursorPos = mb_strlen ($prompt.$string) + 1;
        $this->rewriteLine ($prompt.$string);
        $this->moveCursor ($cursorPos);
      }
      // }}}
      elseif (ord ($char) === 3)
      // Abort (Ctrl+C)
      // {{{
      {
        $this->clearLine ();
        $this->lineContent = "";
        $this->echo ($prompt."\n");
        return "";
      }
      // }}}
      elseif (ord ($char) === 4)
      // Logout (Ctrl+D)
      // {{{
      {
        $string = "exit";
        $this->rewriteLine ($prompt.$string);
        return $string;
      }
      // }}}
      elseif (ord($char) === 12)
      // Refresh page (Ctrl+L)
      // {{{
      {
        echo "\033[2J\033[;H\033c";
        $cursorPos = mb_strlen ($prompt.$string) + 1;
        $this->rewriteLine ($prompt.$string);
        $this->moveCursor ($cursorPos);
      }
      // }}}
      elseif (ord($char) === 21)
      // Empty line from prompt to cursor (Ctrl+U)
      // {{{
      {
        $string = mb_substr ($string, $cursorPos - $minLength);
        $cursorPos = $minLength;
        $this->rewriteLine ($prompt.$string);
        $this->moveCursor ($cursorPos);
      }
      // }}}
      elseif (ord($char) === 23)
      // Remove the last word (Ctrl+W)
      // {{{
      {
        $tmp = mb_substr ($string, 0, $cursorPos - $minLength);
        $end = mb_substr ($string, $cursorPos - $minLength);
        $tmp = rtrim ($tmp);
        $pos = mb_strrpos ($tmp, " ");
        if ($pos !== false)
          $pos++;
        $string = mb_substr ($string, 0, $pos).$end;
        $cursorPos = $minLength + $pos;
        $this->rewriteLine ($prompt.$string);
        $this->moveCursor ($cursorPos);
      }
      // }}}
      elseif (ord($char) === 127)
      // Remove the previous char (Backspace)
      // {{{
      {
        if ($cursorPos <= $minLength)
          continue;
        $strArr = $this->mb_str_split ($string);
        $cursorPos--;
        unset ($strArr[$cursorPos - $minLength]);
        $string = implode ($strArr);
        $this->rewriteLine ($prompt.$string);
        $this->moveCursor ($cursorPos);
      }
      // }}}
      elseif (ord ($char{0}) === 27)
      {
        // ESC SEQUENCE
        /*file_put_contents ("/tmp/debug", "SEQ CHAR=", FILE_APPEND);
        foreach (str_split ($char) as $key)
          file_put_contents ("/tmp/debug", ord ($key)." ", FILE_APPEND);
        file_put_contents ("/tmp/debug", "\n", FILE_APPEND);*/
        if ($char === chr (27).chr (91).chr (49).chr (59).chr (53).chr (67))
        // Cursor right + Ctrl : cursor jump by word
        // {{{
        {
          $tmp = mb_substr ($string, $cursorPos - $minLength);
          $tmp = ltrim ($tmp);
          $pos = strpos ($tmp, " ");
          if ($pos !== false)
            $cursorPos += $pos +1 ;
          else
            $cursorPos = mb_strlen ($prompt.$string) + 1;
          $this->moveCursor ($cursorPos);
        }
        // }}}
        elseif ($char === chr (27).chr (91).chr (49).chr (59).chr (53).chr (68))
        // Cursor left + Ctrl : cursor jump by word
        // {{{
        {
          $tmp = mb_substr ($string, 0, $cursorPos - $minLength);
          $tmp = rtrim ($tmp);
          $pos = strrpos ($tmp, " ");
          if ($pos !== false) $pos++;
          $cursorPos = $minLength + $pos;
          $this->moveCursor ($cursorPos);
        }
        // }}}
        elseif ($char === chr (27).chr (91).chr (65))
        // Cursor up : display the previous history if defined
        // {{{
        {
          if ($string !== "" && $historyTmp == "")
          {
            $historyTmp = $string;
          }
          if ($historyPos > 0)
          {
            $historyPos--;
            $string = $this->history[$historyPos];
            $cursorPos = mb_strlen ($prompt.$string) + 1;
            $this->rewriteLine ($prompt.$string);
            $this->moveCursor ($cursorPos);
          }
        }
        // }}}
        elseif ($char === chr (27).chr (91).chr (66))
        // Cursor down : display the next history if defined
        // {{{
        {
          if ($historyPos < count ($this->history) - 1)
          {
            $historyPos++;
            $string = $this->history[$historyPos];
          }
          elseif ($historyTmp !== "")
          {
            $string = $historyTmp;
          }
          $cursorPos = mb_strlen ($prompt.$string) + 1;
          $this->rewriteLine ($prompt.$string);
          $this->moveCursor ($cursorPos);
        }
        // }}}
        elseif ($char === chr (27).chr (91).chr (67))
        // Cursor right
        // {{{
        {
          if ($cursorPos <= mb_strlen ($this->lineContent))
          {
            $cursorPos++;
            $this->moveCursor ($cursorPos);
          }
        }
        // }}}
        elseif ($char === chr (27).chr (91).chr (68))
        // Cursor left
        // {{{
        {
          if ($cursorPos > $minLength)
          {
            $cursorPos--;
            $this->moveCursor ($cursorPos);
          }
        }
        // }}}
        elseif ($char === chr (27).chr (91).chr (70))
        // End key
        // {{{
        {
          $cursorPos = $minLength + mb_strlen ($string);
          $this->moveCursor ($cursorPos);
        }
        // }}}
        elseif ($char === chr (27).chr (91).chr (72))
        // Home key
        // {{{
        {
          $cursorPos = $minLength;
          $this->moveCursor ($cursorPos);
        }
        // }}}
        elseif ($char === chr (27).chr (91).chr (51).chr (126))
        // Remove the char under the cursor (Delete)
        // {{{
        {
          if ($cursorPos > mb_strlen ($prompt.$string))
            continue;
          $strArr = $this->mb_str_split ($string);
          unset ($strArr[$cursorPos - $minLength]);
          $string = implode ($strArr);
          $this->rewriteLine ($prompt.$string);
          $this->moveCursor ($cursorPos);
        }
        // }}}
      }
      elseif (in_array (ord ($char), $this->nonWriteableChar))
      // Non writeable char : skip it
      // {{{
      {
      }
      // }}}
      else
      // Normal char : Add it to the string
      // {{{
      {
        $strArr = $this->mb_str_split ($string);
        $firstArr = array_slice ($strArr, 0, $cursorPos - $minLength);
        $lastArr = array_slice ($strArr, $cursorPos - $minLength);
        $insertArr = array ($char);
        $strArr = array_merge ($firstArr, $insertArr, $lastArr);
        $string = implode ($strArr);
        $cursorPos++;
        $this->rewriteLine ($prompt.$string);
        $this->moveCursor ($cursorPos);
      }
      // }}}
    }
    return $string;
  }
  // }}}

  /** Rewrite the line with the provided $text.
    * Delete all the old data
    * @param string $text The new text to use on line
    */
  private function rewriteLine ($text)
  // {{{
  {
    if ($this->echoMode)
    {
      // Based on https://stackoverflow.com/a/27850902/158716
      $oldLength = mb_strlen ($this->lineContent);
      // 1. Calculate on which line the cursor is positionned
      $cursorLine = 1 + floor ((-1+$this->cursorPos) / $this->termWidth);
      $lastLines = 1 + floor ((1+$oldLength) / $this->termWidth);
      for ($i = $cursorLine ; $i < $lastLines ; $i++)
        echo "\033[1B";
      // 3. Remove the lines from lastLines to line 1
      if ($lastLines > 1)
      {
        for ($i = $lastLines ; $i > 1 ; $i--)
          echo "\r\033[K\033[1A\r";
      }
      // 4. Clean the line 1
      echo "\r\033[K";
      $this->lineContent = $text;
      echo $this->lineContent;
      $this->cursorPos = mb_strlen ($this->lineContent);
    }
  }
  // }}}

  /** Move the cursor on position $position. The first column is $cursorPos=1
    * @param integer $cursorPos The new position on line
    */
  private function moveCursor ($cursorPos)
  // {{{
  {
    if ($cursorPos < 1)
      $this->consoleException ("MoveCursor lesser than one : $cursorPos");
    if ($this->echoMode)
    {
      $oldLength = mb_strlen ($this->lineContent);
      // 1. Calculate on which line the cursor is positionned
      $cursorLine = 1 + floor ((-1+$this->cursorPos) / $this->termWidth);
      // 2. Return the cursor to the first line
      for ($i = $cursorLine ; $i > 1 ; $i--)
        echo chr (27).chr (91).chr (49).chr (65)."\r";
      // 3. Down the cursor to the wanted line
      $wantedLine = ceil ($cursorPos / $this->termWidth);
      if ($wantedLine > 1)
      {
        for ($i = 1 ; $i < $wantedLine ; $i++)
          echo "\r".chr (27).chr (91).chr (49).chr (66)."\r";
      }
      // 4. Move the cursor on the last line
      $needMovePos = -1 + $cursorPos - ($wantedLine - 1) * $this->termWidth;
      echo "\r".str_repeat (chr (27).chr (91).chr (67), $needMovePos);
      $this->cursorPos = $cursorPos;
    }
  }
  // }}}

  /** Clear the existing line.
    */
  public function clearLine ()
  // {{{
  {
    echo "\r".str_repeat (" ", mb_strlen ($this->lineContent))."\r";
    $this->lineContent = "";
  }
  // }}}

  /** Call a specific function when a completion key is pressed
    * @param string|bool $completionKeys The list of the completion keys. False
    * unset the method
    * @param callable $completionFunction The function called when one of the
    * completion keys is pressed.
    * The function must get the partial text as first parameter, and must return
    * an array with the possibilities
    */
  public function completeFunction ($completionKeys, $completionFunction)
  // {{{
  {
    if (! is_string ($completionKeys) && ! is_boolean ($completionKeys))
      $this->consoleException ("Can not set the completionKeys : not a string");
    if ($completionKeys === true)
      $this->consoleException ("Can not set the completionKeys : not false");
    if (! is_callable ($completionFunction))
      $this->consoleException ("Can not set the completionFunction : ".
        "not a callable function");
    $this->completionKeys = $completionKeys;
    $this->completionFunction = $completionFunction;
  }
  // }}}

  /** Get the actual history in memory
    */
  public function getHistory ()
  // {{{
  {
    return $this->history;
  }
  // }}}

  /** Clear the history
    * Do NOT write the empty history on disk
    */
  public function clearHistory ()
  // {{{
  {
    $this->history = array ();
    return $this;
  }
  // }}}

  /** Write the history to disk.
    * @param string $historyFile The history file where the history is stored
    */
  public function writeHistory ($historyFile)
  // {{{
  {
    if (file_exists ($historyFile))
    {
      if (! is_writeable ($historyFile))
        $this->consoleException ("History file '$historyFile' ".
          "is not writeable");
      $history = file_get_contents ($historyFile);
      if ($history === false)
        $this->consoleException ("History file '$historyFile' can not be read");
      $historyArr = explode ("\n", $history);
      if (! isset ($historyArr[0]) || $historyArr[0] !== "__HISTORY__")
        $this->consoleException ("History file '$historyFile' ".
          "is not an history file : do not touch\n");
    }
    elseif (! file_exists (dirname ($historyFile)))
      $this->consoleException ("History file '$historyFile' ".
        "can not be created: parent directory doesn't exists");
    elseif (! is_dir (dirname ($historyFile)))
      $this->consoleException ("History file '$historyFile' ".
        "can not be created: parent directory is not a directory");
    file_put_contents ($historyFile, "__HISTORY__\n");
    file_put_contents ($historyFile, implode ("\n", $this->history),
      FILE_APPEND);
    return $this;
  }
  // }}}

  /** Read the history from the disk
    * If the file doesn't exists, return an empty array
    * @param string $historyFile The history file where the history is stored
    */
  public function readHistory ($historyFile)
  // {{{
  {
    if (! file_exists ($historyFile))
    {
      $this->history = array ();
      return array ();
    }
    if (! is_readable ($historyFile))
      $this->consoleException ("History file '$historyFile' can not be read");
    $history = file_get_contents ($historyFile);
    if ($history === false)
      $this->consoleException ("History file '$historyFile' can not be read");
    $historyArr = explode ("\n", $history);
    if (! isset ($historyArr[0]) || $historyArr[0] !== "__HISTORY__")
      $this->consoleException ("History file '$historyFile' ".
        "is not an history file : do not touch\n");
    array_shift ($historyArr);
    $this->history = $historyArr;
    return $this->history;
  }
  // }}}

  /** Add a new entry in history.
    * The new line can not be empty : it is not stored, but without error
    * Do NOT write the history on disk.
    * @param string The new entry to add in history
    */
  public function addHistory ($line)
  // {{{
  {
    if (! is_string ($line))
      $this->consoleException ("Can not add line to history : ".
        "it is not a string");
    if (trim ($line) === "")
      return $this;
    $this->history[] = $line;
    $this->history = array_slice ($this->history, -$this->historyMaxSize);
    return $this;
  }
  // }}}

  /** Get/Set the maximum number of entries in the history
    * If null, get the defined maximum number
    * @param integer|null $historyMaxSize The maximum number of entries
    */
  public function historyMaxSize ($historyMaxSize = null)
  // {{{
  {
    if ($historyMaxSize === null)
      return $this->historyMaxSize;
    if (intval ($historyMaxSize) < 1)
      $this->consoleException ("Can not set the historyMaxSize : ".
        "negative value provided");
    $this->historyMaxSize = intval ($historyMaxSize);
  }
  // }}}

  /** Error management
    * @param string $message The message to throw in the exception
    */
  public function consoleException ($message)
  // {{{
  {
    throw new \Exception ($message, 500);
  }
  // }}}

  /** This function return an array with each char, but supports UTF-8
    * @param string $string The string to explode
    * @param integer $split_length The number of chars in each split
    * @return array
    */
  private function mb_str_split ($string, $split_length = 1)
  // {{{
  {
    $res = array();
    for ($i = 0; $i < mb_strlen ($string); $i += $split_length)
      $res[] = mb_substr ($string, $i, $split_length);
    return $res;
  }
  // }}}

  /** This function debug the data
    * @param mixed $data The data to store
    */
  private function debug ($data)
  // {{{
  {
    if (is_array ($data) || is_bool ($data))
      $data = var_export ($data, true);
    file_put_contents ("/tmp/debug", date ("H:i:s")." $data\n", FILE_APPEND);
  }
  // }}}
}