<?php
// $Id$
/******************************************************************************/
/***************************** EDIT EXAMPLE ***********************************/
/******************************************************************************/
function upload_examples_edit_form($form, $form_state)
{
	global $user;
	$example_id = arg(3);
	/* get example details */
	/*$example_q = db_query("SELECT * FROM {textbook_companion_example} WHERE id = %d LIMIT 1", $example_id);
	$example_data = db_fetch_object($example_q);*/
	$query = db_select('textbook_companion_example');
	$query->fields('textbook_companion_example');
	$query->condition('id', $example_id);
	$query->range(0, 1);
	$example_q = $query->execute();
	$example_data = $example_q->fetchObject();
	if (!$example_q)
	{
		drupal_set_message(t("Invalid example selected."), 'error');
		drupal_goto('');
		return;
	} //!$example_q
	if ($example_data->approval_status != 0)
	{
		drupal_set_message(t("You cannot edit an example after it has been approved or dis-approved. Please contact site administrator if you want to edit this example."), 'error');
		drupal_goto('');
		return;
	} //$example_data->approval_status != 0
	/* get examples files */
	$source_file = "";
	$source_id = 0;
	$result1_file = "";
	$result1_id = 0;
	$result2_file = "";
	$result2_id = 0;
	$xcos1_file = "";
	$xcos1_id = 0;
	$xcos2_file = "";
	$xcos2_id = 0;
	/*$example_files_q = db_query("SELECT * FROM {textbook_companion_example_files} WHERE example_id = %d", $example_id);*/
	$query = db_select('textbook_companion_example_files');
	$query->fields('textbook_companion_example_files');
	$query->condition('example_id', $example_id);
	$example_files_q = $query->execute();
	while ($example_files_data = $example_files_q->fetchObject())
	{
		if ($example_files_data->filetype == "S")
		{
			$source_file = l($example_files_data->filename, 'download/file/' . $example_files_data->id);
			$source_file_id = $example_files_data->id;
		} //$example_files_data->filetype == "S"
		if ($example_files_data->filetype == "R")
		{
			if (strlen($result1_file) == 0)
			{
				$result1_file = l($example_files_data->filename, 'download/file/' . $example_files_data->id);
				$result1_file_id = $example_files_data->id;
			} //strlen($result1_file) == 0
			else
			{
				$result2_file = l($example_files_data->filename, 'download/file/' . $example_files_data->id);
				$result2_file_id = $example_files_data->id;
			}
		} //$example_files_data->filetype == "R"
		if ($example_files_data->filetype == "X")
		{
			if (strlen($xcos1_file) <= 0)
			{
				$xcos1_file = l($example_files_data->filename, 'download/file/' . $example_files_data->id);
				$xcos1_file_id = $example_files_data->id;
			} //strlen($xcos1_file) <= 0
			else
			{
				$xcos2_file = l($example_files_data->filename, 'download/file/' . $example_files_data->id);
				$xcos2_file_id = $example_files_data->id;
			}
		} //$example_files_data->filetype == "X"
	} //$example_files_data = $example_files_q->fetchObject()
	/* get chapter details */
	/*$chapter_q = db_query("SELECT * FROM {textbook_companion_chapter} WHERE id = %d", $example_data->chapter_id);
	$chapter_data = db_fetch_object($chapter_q);*/
	$query = db_select('textbook_companion_chapter');
	$query->fields('textbook_companion_chapter');
	$query->condition('id', $example_data->chapter_id);
	$result = $query->execute();
	$chapter_data = $result->fetchObject();
	if (!$chapter_data)
	{
		drupal_set_message(t("Invalid chapter selected."), 'error');
		drupal_goto('');
		return;
	} //!$chapter_data
	/* get preference details */
	/*$preference_q = db_query("SELECT * FROM {textbook_companion_preference} WHERE id = %d", $chapter_data->preference_id);
	$preference_data = db_fetch_object($preference_q);*/
	$query = db_select('textbook_companion_preference');
	$query->fields('textbook_companion_preference');
	$query->condition('id', $chapter_data->preference_id);
	$result = $query->execute();
	$preference_data = $result->fetchObject();
	if (!$preference_data)
	{
		drupal_set_message(t("Invalid book selected."), 'error');
		drupal_goto('');
		return;
	} //!$preference_data
	if ($preference_data->approval_status != 1)
	{
		drupal_set_message(t("Cannot edit example. Either the book proposal has not been approved or it has been rejected."), 'error');
		drupal_goto('');
		return;
	} //$preference_data->approval_status != 1
	/* get proposal details */
	/*$proposal_q = db_query("SELECT * FROM {textbook_companion_proposal} WHERE id = %d", $preference_data->proposal_id);
	$proposal_data = db_fetch_object($proposal_q);*/
	$query = db_select('textbook_companion_proposal');
	$query->fields('textbook_companion_proposal');
	$query->condition('id', $preference_data->proposal_id);
	$result = $query->execute();
	$proposal_data = $result->fetchObject();
	if (!$proposal_data)
	{
		drupal_set_message(t("Invalid proposal selected."), 'error');
		drupal_goto('');
		return;
	} //!$proposal_data
	if ($proposal_data->uid != $user->uid)
	{
		drupal_set_message(t("You do not have permissions to edit this example."), 'error');
		drupal_goto('');
		return;
	} //$proposal_data->uid != $user->uid
	$user_data = user_load($proposal_data->uid);
	/* add javascript for automatic book title, check if example uploaded, dependency selection effects */
	$chapter_name_js = " (function ($) {
			$(document).ready(function() {
    $('#edit-existing-depfile-dep-book-title').change(function() {
      var dep_selected = ''; 
      /* showing and hiding relevant files */
    $('.form-checkboxes .option').hide();
      $('.form-checkboxes .option').each(function(index) {
        var activeClass = $('#edit-existing-depfile-dep-book-title').val();
        if ($(this).children().hasClass(activeClass)) {
          $(this).show();
        }
        if ($(this).children().attr('checked') == true) {
          dep_selected += $(this).children().next().text() + '<br />';
        }
      });
      /* showing list of already existing dependencies */
     $('#existing_depfile_selected').html(dep_selected);
    });

    $('.form-checkboxes .option').change(function() {
      $('#edit-existing-depfile-dep-book-title').trigger('change');
    });
    $('#edit-existing-depfile-dep-book-title').trigger('change');
  });
})(jQuery);";
	drupal_add_js($chapter_name_js, 'inline', 'header');
	$form['#redirect'] = 'textbook_companion/code';
	$form['#attributes'] = array(
		'enctype' => "multipart/form-data"
	);
	$form['book_details']['book'] = array(
		'#type' => 'item',
		'#markup' => $preference_data->book,
		'#title' => t('Title of the Book')
	);
	$form['contributor_name'] = array(
		'#type' => 'item',
		'#markup' => $proposal_data->full_name,
		'#title' => t('Contributor Name')
	);
	$form['number'] = array(
		'#type' => 'item',
		'#title' => t('Chapter No'),
		'#markup' => $chapter_data->number
	);
	$form['name'] = array(
		'#type' => 'item',
		'#title' => t('Title of the Chapter'),
		'#markup' => $chapter_data->name
	);
	$form['example_number'] = array(
		'#type' => 'item',
		'#title' => t('Example No'),
		'#markup' => $example_data->number
	);
	$form['example_caption'] = array(
		'#type' => 'textfield',
		'#title' => t('Caption'),
		'#size' => 40,
		'#maxlength' => 255,
		'#required' => TRUE,
		'#default_value' => $example_data->caption
	);
	$form['example_warning'] = array(
		'#type' => 'item',
		'#title' => t('You should upload all the files (main or source files, result files, executable file if any)'),
		'#prefix' => '<div style="color:red">',
		'#suffix' => '</div>'
	);
	$form['sourcefile'] = array(
		'#type' => 'fieldset',
		'#title' => t('Main or Source Files'),
		'#collapsible' => FALSE,
		'#collapsed' => FALSE
	);
	if ($source_file)
	{
		$form['sourcefile']['cur_source'] = array(
			'#type' => 'item',
			'#title' => t('Existing Main or Source File'),
			'#markup' => $source_file
		);
		$form['sourcefile']['source_file_action_note'] = array(
			'#type' => 'item',
			'#title' => t('Note:'),
			'#markup' => t("<Strong style='color:red' >Use Replace option to upload your corrected code. Do not delete the example if your book is under review, you can always edit and upload it by the Replace option.</strong>")
		);
		$form['sourcefile']['source_file_action'] = array(
			'#type' => 'radios',
			'#options' => array(
				'1' => "Replace Existing Main or Source File<br>",
				'2' => "Delete Existing Main or Source File"
			),
			'#title' => t('Select Action'),
			'#required' => TRUE
		);
		$form['sourcefile']['sourcefile1'] = array(
			'#type' => 'file',
			'#title' => t('Upload New Main or Source File'),
			'#size' => 48,
			'#description' => t("<Strong style='color:red' >Upload new Main or Source file above, if you want to replace the existing file. Leave blank if you want to keep using the existing file.</strong> <br />") . t('Allowed file extensions : ') . variable_get('textbook_companion_source_extensions', ''),
			'#states' => array(
				'visible' => array(
					':input[name="source_file_action"]' => array(
						'value' => '1'
					)
				)
			)
		);
		/*
		$form['sourcefile']['cur_source_checkbox'] = array(
		'#type' => 'checkbox',
		'#title' => t('Delete Existing Main or Source File'),
		'#description' => 'Check to delete the existing Main or Source file.',
		'#states' => array(
		'visible' => array(
		':input[name="source_file_action"]' => array('value' => '2'),
		),
		),
		);
		*/
		$form['sourcefile']['cur_source_file_id'] = array(
			'#type' => 'hidden',
			'#value' => $source_file_id
		);
	} //$source_file
	else
	{
		$form['sourcefile']['sourcefile1'] = array(
			'#type' => 'file',
			'#title' => t('Upload New Main or Source File'),
			'#size' => 48,
			'#description' => t('Allowed file extensions : ') . variable_get('textbook_companion_source_extensions', '')
		);
	}
	$form['dep_files'] = array(
		'#type' => 'item',
		'#title' => t('Dependency Files')
	);
	/************ START OF EXISTING DEPENDENCIES **************/
	$dependency_files = array();
	/*$dependency_q = db_query("SELECT * FROM {textbook_companion_example_dependency} WHERE example_id = %d", $example_data->id);*/
	$query = db_select('textbook_companion_example_dependency');
	$query->fields('textbook_companion_example_dependency');
	$query->condition('example_id', $example_data->id);
	$dependency_q = $query->execute();
	while ($dependency_data = $dependency_q->fetchObject())
	{
		$dependency_files[] = $dependency_data->dependency_id;
	} //$dependency_data = $dependency_q->fetchObject()
	/* existing dependencies */
	$form['existing_depfile'] = array(
		'#type' => 'fieldset',
		'#title' => t('Use Already Existing Dependency Files'),
		'#collapsible' => FALSE,
		'#collapsed' => FALSE,
		'#prefix' => '<div id="existing-depfile-wrapper">',
		'#suffix' => '</div>',
		'#tree' => TRUE
	);
	/* existing dependencies */
	/*$form['existing_depfile']['selected'] = array(
	'#type' => 'item',
	'#title' => t('Existing Dependency Files Selected'),
	'#markup' => '<div id="existing_depfile_selected"></div>',
	);
	
	$form['existing_depfile']['dep_book_title'] = array(
	'#type' => 'select',
	'#title' => t('Title of the Book'),
	'#options' => _list_of_book_titles(),
	);
	
	list($files_options, $files_options_class) = _list_of_book_dependency_files();
	$form['existing_depfile']['dep_chapter_example_files'] = array(
	'#type' => 'checkboxes',
	'#title' => t('Dependency Files'),
	'#options' => $files_options,
	'#options_class' => $files_options_class,
	'#multiple' => TRUE,
	'#default_value' => $dependency_files,
	);*/
	/* existing dependencies */
	$form['existing_depfile']['selected'] = array(
		'#type' => 'item',
		'#title' => t('Existing Dependency Files Selected'),
		'#markup' => '<div id="existing_depfile_selected"></div>'
	);
	/* $form['existing_depfile']['dep_book_title'] = array(
	'#type' => 'select',
	'#title' => t('Title of the Book'),
	'#options' => _list_of_book_titles(),
	);*/
	$form['existing_depfile']['dep_book'] = array(
		'#type' => 'item',
		'#title' => t('Dependency Files')
	);
	list($files_options, $files_options_class) = _list_of_book_dependency_files();
	$form['existing_depfile']['dep_chapter_example_files'] = array(
		'#type' => 'checkboxes',
		//'#title' => t('Dependency Files'),
		'#options' => $files_options,
		'#options_class' => $files_options_class,
		'#prefix' => '<div id="ckb" style="height:500px;overflow:auto;">',
		'#suffix' => '</div>',
		'#multiple' => TRUE
	);
	$form['existing_depfile']['dep_upload'] = array(
		'#type' => 'item',
		'#markup' => '<hr style="color:red">' . l('Upload New Depedency Files', 'textbook_companion/code/upload_dep')
	);
	/************ END OF EXISTING DEPENDENCIES **************/
	$form['result'] = array(
		'#type' => 'fieldset',
		'#title' => t('Result Files'),
		'#collapsible' => FALSE,
		'#collapsed' => FALSE
	);
	if ($result1_file)
	{
		$form['result']['cur_result1'] = array(
			'#type' => 'item',
			'#title' => t('Existing Result File 1'),
			'#markup' => $result1_file
		);
		$form['result']['cur_result1_checkbox'] = array(
			'#type' => 'checkbox',
			'#title' => t('Delete Existing Result File 1'),
			'#description' => 'Check to delete the existing Result file.'
		);
		$form['result']['result1'] = array(
			'#type' => 'file',
			'#title' => t('Upload New Result File 1'),
			'#size' => 48,
			'#description' => t("Upload new Result file above if you want to replace the existing file, leave blank if you want to keep using the existing file. <br />") . t('Allowed file extensions : ') . variable_get('textbook_companion_result_extensions', '')
		);
		$form['result']['cur_result1_file_id'] = array(
			'#type' => 'hidden',
			'#value' => $result1_file_id
		);
	} //$result1_file
	else
	{
		$form['result']['result1'] = array(
			'#type' => 'file',
			'#title' => t('Upload New Result File 1'),
			'#size' => 48,
			'#description' => t('Allowed file extensions : ') . variable_get('textbook_companion_result_extensions', '')
		);
	}
	$form['result']['br'] = array(
		'#type' => 'item',
		'#markup' => "<br />"
	);
	if ($result2_file)
	{
		$form['result']['cur_result2'] = array(
			'#type' => 'item',
			'#title' => t('Existing Result File 2'),
			'#markup' => $result2_file
		);
		$form['result']['cur_result2_checkbox'] = array(
			'#type' => 'checkbox',
			'#title' => t('Delete Existing Result File 2'),
			'#description' => 'Check to delete the existing Result file.'
		);
		$form['result']['result2'] = array(
			'#type' => 'file',
			'#title' => t('Upload New Result file 2'),
			'#size' => 48,
			'#description' => t("Upload new Result file above if you want to replace the existing file. Leave blank if you want to keep using the existing file. <br />") . t('Allowed file extensions : ') . variable_get('textbook_companion_result_extensions', '')
		);
		$form['result']['cur_result2_file_id'] = array(
			'#type' => 'hidden',
			'#value' => $result2_file_id
		);
	} //$result2_file
	else
	{
		$form['result']['result2'] = array(
			'#type' => 'file',
			'#title' => t('Upload New Result file 2'),
			'#size' => 48,
			'#description' => t('Allowed file extensions : ') . variable_get('textbook_companion_result_extensions', '')
		);
	}
	$form['xcos'] = array(
		'#type' => 'fieldset',
		'#title' => t('XCOS Files'),
		'#collapsible' => FALSE,
		'#collapsed' => FALSE
	);
	if ($xcos1_file)
	{
		$form['xcos']['cur_xcos1'] = array(
			'#type' => 'item',
			'#title' => t('Existing xcos File 1'),
			'#markup' => $xcos1_file
		);
		$form['xcos']['cur_xcos1_checkbox'] = array(
			'#type' => 'checkbox',
			'#title' => t('Delete Existing xcos File 1'),
			'#description' => 'Check to delete the existing xcos file.'
		);
		$form['xcos']['xcos1'] = array(
			'#type' => 'file',
			'#title' => t('Upload New xcos file 1'),
			'#size' => 48,
			'#description' => t("Upload new xcos file above if you want to replace the existing file. Leave blank if you want to keep using the existing file. <br />") . t('Allowed file extensions : ') . variable_get('textbook_companion_xcos_extensions', '')
		);
		$form['sourcefile']['cur_xcos1_file_id'] = array(
			'#type' => 'hidden',
			'#value' => $xcos1_file_id
		);
	} //$xcos1_file
	else
	{
		$form['xcos']['xcos1'] = array(
			'#type' => 'file',
			'#title' => t('Upload New xcos file 1'),
			'#size' => 48,
			'#description' => t('Allowed file extensions : ') . variable_get('textbook_companion_xcos_extensions', '')
		);
	}
	$form['xcos']['br'] = array(
		'#type' => 'item',
		'#markup' => "<br />"
	);
	if ($xcos2_file)
	{
		$form['xcos']['cur_xcos2'] = array(
			'#type' => 'item',
			'#title' => t('Existing xcos File 2'),
			'#markup' => $xcos2_file
		);
		$form['xcos']['cur_xcos2_checkbox'] = array(
			'#type' => 'checkbox',
			'#title' => t('Delete Existing xcos File 2'),
			'#description' => 'Check to delete the existing xcos file.'
		);
		$form['xcos']['xcos2'] = array(
			'#type' => 'file',
			'#title' => t('Upload New xcos file 2'),
			'#size' => 48,
			'#description' => t("Upload new xcos file above if you want to replace the existing file. Leave blank if you want to keep using the existing file. <br />") . t('Allowed file extensions : ') . variable_get('textbook_companion_xcos_extensions', '')
		);
		$form['xcos']['cur_xcos2_file_id'] = array(
			'#type' => 'hidden',
			'#value' => $xcos2_file_id
		);
	} //$xcos2_file
	else
	{
		$form['xcos']['xcos2'] = array(
			'#type' => 'file',
			'#title' => t('Upload New xcos file 2'),
			'#size' => 48,
			'#description' => t('Allowed file extensions : ') . variable_get('textbook_companion_xcos_extensions', '')
		);
	}
	$form['submit'] = array(
		'#type' => 'submit',
		'#value' => t('Submit')
	);
	$form['cancel'] = array(
		'#type' => 'markup',
		'#value' => l(t('Cancel'), 'textbook_companion/code')
	);
	return $form;
}
function upload_examples_edit_form_validate($form, &$form_state)
{
	if (!check_name($form_state['values']['example_caption']))
		form_set_error('example_caption', t('Example Caption can contain only alphabets, numbers and spaces.'));
	if (isset($_FILES['files']))
	{
		/* check for valid filename extensions */
		foreach ($_FILES['files']['name'] as $file_form_name => $file_name)
		{
			if ($file_name)
			{
				/* checking file type */
				if (strstr($file_form_name, 'source'))
					$file_type = 'S';
				else if (strstr($file_form_name, 'result'))
					$file_type = 'R';
				else if (strstr($file_form_name, 'xcos'))
					$file_type = 'X';
				else
					$file_type = 'U';
				$allowed_extensions_str = '';
				switch ($file_type)
				{
					case 'S':
						$allowed_extensions_str = variable_get('textbook_companion_source_extensions', '');
						break;
					case 'R':
						$allowed_extensions_str = variable_get('textbook_companion_result_extensions', '');
						break;
					case 'X':
						$allowed_extensions_str = variable_get('textbook_companion_xcos_extensions', '');
						break;
				} //$file_type
				$allowed_extensions = explode(',', $allowed_extensions_str);
				$temp_extension = end(explode('.', strtolower($_FILES['files']['name'][$file_form_name])));
				if (!in_array($temp_extension, $allowed_extensions))
					form_set_error($file_form_name, t('Only file with ' . $allowed_extensions_str . ' extensions can be uploaded.'));
				if ($_FILES['files']['size'][$file_form_name] <= 0)
					form_set_error($file_form_name, t('File size cannot be zero.'));
				/* check if valid file name */
				if (!textbook_companion_check_valid_filename($_FILES['files']['name'][$file_form_name]))
					form_set_error($file_form_name, t('Invalid file name specified. Only alphabets, numbers and underscore is allowed as a valid filename.'));
			} //$file_name
		} //$_FILES['files']['name'] as $file_form_name => $file_name
	} //isset($_FILES['files'])
	/* add javascript again for automatic book title, check if example uploaded, dependency selection effects */
	$chapter_name_js = " $(document).ready(function() {
    $('#edit-number').change(function() {
      $.get('" . base_path() . "textbook_companion/ajax/chapter_title/' + $('#edit-number').val() + '/' + " . $row->pre_id . ", function(data) {
        $('#edit-name').val(data);
      });
    });
    $('#edit-example-number').change(function() {
      $.get('" . base_path() . "textbook_companion/ajax/example_exists/' + $('#edit-number').val() + '/' + $('#edit-example-number').val(), function(data) {
        if (data) {
          alert(data);
        }
      });
    });
    $('#edit-existing-depfile-dep-book-title').change(function() {
      var dep_selected = ''; 
      /* showing and hiding relevant files */
      $('.form-checkboxes .option').hide();
      $('.form-checkboxes .option').each(function(index) {
        var activeClass = $('#edit-existing-depfile-dep-book-title').val();
        if ($(this).children().hasClass(activeClass)) {
          $(this).show();
        }
        if ($(this).children().attr('checked') == true) {
          dep_selected += $(this).children().next().text() + '<br />';
        }
      });
      /* showing list of already existing dependencies */
      $('#existing_depfile_selected').html(dep_selected);
    });

    $('.form-checkboxes .option').change(function() {
      $('#edit-existing-depfile-dep-book-title').trigger('change');
    });
    $('#edit-existing-depfile-dep-book-title').trigger('change');
  });";
	drupal_add_js($chapter_name_js, 'inline', 'header');
}
function upload_examples_edit_form_submit($form, &$form_state)
{
	global $user;
	$example_id = arg(3);
	/* get example details */
	/*$example_q = db_query("SELECT * FROM {textbook_companion_example} WHERE id = %d LIMIT 1", $example_id);
	$example_data = db_fetch_object($example_q);*/
	$query = db_select('textbook_companion_example');
	$query->fields('textbook_companion_example');
	$query->condition('id', $example_id);
	$query->range(0, 1);
	$example_q = $query->execute();
	$example_data = $example_q->fetchObject();
	if (!$example_q)
	{
		drupal_set_message(t("Invalid example selected."), 'error');
		drupal_goto('');
		return;
	} //!$example_q
	if ($example_data->approval_status != 0)
	{
		drupal_set_message(t("You cannot edit an example after it has been approved or dis-approved. Please contact site administrator if you want to edit this example."), 'error');
		drupal_goto('');
		return;
	} //$example_data->approval_status != 0
	/* get chapter details */
	/*$chapter_q = db_query("SELECT * FROM {textbook_companion_chapter} WHERE id = %d", $example_data->chapter_id);
	$chapter_data = db_fetch_object($chapter_q);*/
	$query = db_select('textbook_companion_chapter');
	$query->fields('textbook_companion_chapter');
	$query->condition('id', $example_data->chapter_id);
	$result = $query->execute();
	$chapter_data = $result->fetchObject();
	if (!$chapter_data)
	{
		drupal_set_message(t("Invalid chapter selected."), 'error');
		drupal_goto('');
		return;
	} //!$chapter_data
	/* get preference details */
	/*$preference_q = db_query("SELECT * FROM {textbook_companion_preference} WHERE id = %d", $chapter_data->preference_id);
	$preference_data = db_fetch_object($preference_q);*/
	$query = db_select('textbook_companion_preference');
	$query->fields('textbook_companion_preference');
	$query->condition('id', $chapter_data->preference_id);
	$result = $query->execute();
	$preference_data = $result->fetchObject();
	if (!$preference_data)
	{
		drupal_set_message(t("Invalid book selected."), 'error');
		drupal_goto('');
		return;
	} //!$preference_data
	if ($preference_data->approval_status != 1)
	{
		drupal_set_message(t("Cannot edit example. Either the book proposal has not been approved or it has been rejected."), 'error');
		drupal_goto('');
		return;
	} //$preference_data->approval_status != 1
	/* get proposal details */
	/*$proposal_q = db_query("SELECT * FROM {textbook_companion_proposal} WHERE id = %d", $preference_data->proposal_id);
	$proposal_data = db_fetch_object($proposal_q);*/
	$query = db_select('textbook_companion_proposal');
	$query->fields('textbook_companion_proposal');
	$query->condition('id', $preference_data->proposal_id);
	$result = $query->execute();
	$proposal_data = $result->fetchObject();
	if (!$proposal_data)
	{
		drupal_set_message(t("Invalid proposal selected."), 'error');
		drupal_goto('');
		return;
	} //!$proposal_data
	if ($proposal_data->uid != $user->uid)
	{
		drupal_set_message(t("You do not have permissions to edit this example."), 'error');
		drupal_goto('');
		return;
	} //$proposal_data->uid != $user->uid
	/* creating directories */
	$root_path = textbook_companion_path();
	$dest_path = $preference_data->id . '/';
	if (!is_dir($root_path . $dest_path))
		mkdir($root_path . $dest_path);
	$dest_path .= 'CH' . $chapter_data->number . '/';
	if (!is_dir($root_path . $dest_path))
		mkdir($root_path . $dest_path);
	$dest_path .= 'EX' . $example_data->number . '/';
	if (!is_dir($root_path . $dest_path))
		mkdir($root_path . $dest_path);
	/* updating example caption */
	/*db_query("UPDATE {textbook_companion_example} SET caption = '%s' WHERE id = %d", $form_state['values']['example_caption'], $example_id);*/
	$query = db_update('textbook_companion_example');
	$query->fields(array(
		'caption' => $form_state['values']['example_caption']
	));
	$query->condition('id', $example_id);
	$num_updated = $query->execute();
	/* handling dependencies */
	/*db_query("DELETE FROM {textbook_companion_example_dependency} WHERE example_id = %d", $example_data->id);*/
	$query = db_delete('textbook_companion_example_dependency');
	$query->condition('example_id', $example_data->id);
	$num_deleted = $query->execute();
	foreach ($form_state['values']['existing_depfile']['dep_chapter_example_files'] as $row)
	{
		if ($row > 0)
		{
			/* insterting into database */
			/*db_query("INSERT INTO {textbook_companion_example_dependency} (example_id, dependency_id, approval_status, timestamp)
			VALUES (%d, %d, %d, %d)",
			$example_data->id,
			$row,
			0,
			time()
			);*/
			$query = "INSERT INTO {textbook_companion_example_dependency} (example_id, dependency_id, approval_status, timestamp)
        VALUES (:example_id, :dependency_id, :approval_status, :timestamp)";
			$args = array(
				":example_id" => $example_data->id,
				":dependency_id" => $row,
				":approval_status" => 0,
				":timestamp" => time()
			);
			$result = db_query($query, $args, array(
				'return' => Database::RETURN_INSERT_ID
			));
		} //$row > 0
	} //$form_state['values']['existing_depfile']['dep_chapter_example_files'] as $row
	/* handle source file */
	$cur_file_id = $form_state['values']['cur_source_file_id'];
	if ($cur_file_id > 0)
	{
		/*$file_q = db_query("SELECT * FROM  {textbook_companion_example_files} WHERE id = %d AND example_id = %d", $cur_file_id, $example_data->id);
		$file_data = db_fetch_object($file_q);*/
		$query = db_select('textbook_companion_example_files');
		$query->fields('textbook_companion_example_files');
		$query->condition('id', $cur_file_id);
		$query->condition('example_id', $example_data->id);
		$result = $query->execute();
		$file_data = $result->fetchObject();
		if (!$file_data)
		{
			drupal_set_message("Error deleting example source file. File not present in database.", 'error');
			return;
		} //!$file_data
		if (($form_state['values']['source_file_action'] == 2) && (!$_FILES['files']['name']['sourcefile1']))
		{
			if (!delete_file($cur_file_id))
			{
				drupal_set_message("Error deleting example source file.", 'error');
				return;
			} //!delete_file($cur_file_id)
		} //($form_state['values']['cur_source_checkbox'] == 1) && (!$_FILES['files']['name']['sourcefile1'])
	} //$cur_file_id > 0
	if ($_FILES['files']['name']['sourcefile1'])
	{
		if ($cur_file_id > 0)
		{
			if (!delete_file($cur_file_id))
			{
				drupal_set_message("Error removing previous example source file.", 'error');
				return;
			} //!delete_file($cur_file_id)
		} //$cur_file_id > 0
		if (file_exists($root_path . $dest_path . $_FILES['files']['name']['sourcefile1']))
		{
			drupal_set_message(t("Error uploading source file. File !filename already exists.", array(
				'!filename' => $_FILES['files']['name']['sourcefile1']
			)), 'error');
			return;
		} //file_exists($root_path . $dest_path . $_FILES['files']['name']['sourcefile1'])
		/* uploading file */
		if (move_uploaded_file($_FILES['files']['tmp_name']['sourcefile1'], $root_path . $dest_path . $_FILES['files']['name']['sourcefile1']))
		{
			/* for uploaded files making an entry in the database */
			/*db_query("INSERT INTO {textbook_companion_example_files} (example_id, filename, filepath, filemime, filesize, filetype, timestamp)
			VALUES (%d, '%s', '%s', '%s', %d, '%s', %d)",
			$example_data->id,
			$_FILES['files']['name']['sourcefile1'],
			$dest_path . $_FILES['files']['name']['sourcefile1'],
			$_FILES['files']['type']['sourcefile1'],
			$_FILES['files']['size']['sourcefile1'],
			'S',
			time()
			);*/
			var_dump('ok');
			$query = "INSERT INTO {textbook_companion_example_files} (example_id, filename, filepath, filemime, filesize, filetype,	timestamp)
		 VALUES (:example_id, :filename, :filepath, :filemime, :filesize, :filetype,:timestamp)";
			$args = array(
				":example_id" => $example_data->id,
				":filename" => $_FILES['files']['name']['sourcefile1'],
				":filepath" => $dest_path . $_FILES['files']['name']['sourcefile1'],
				":filemime" => $_FILES['files']['type']['sourcefile1'],
				":filesize" => $_FILES['files']['size']['sourcefile1'],
				":filetype" => 'S',
				":timestamp" => time()
			);
			/*var_dump( ":example_id=>". $example_data->id .",". ":filename=>". $_FILES['files']['name']['sourcefile1'] .",".
			":filepath=>". $dest_path . $_FILES['files']['name']['sourcefile1'].",".
			":filemime=>". $_FILES['files']['type']['sourcefile1'].",".
			":filesize=>" .$_FILES['files']['size']['sourcefile1']
			);die;
			*/
			$result = db_query($query, $args, array(
				'return' => Database::RETURN_INSERT_ID
			));
			drupal_set_message($_FILES['files']['name']['sourcefile1'] . ' uploaded successfully.', 'status');
		} //move_uploaded_file($_FILES['files']['tmp_name']['sourcefile1'], $root_path . $dest_path . $_FILES['files']['name']['sourcefile1'])
		else
		{
			drupal_set_message('Error uploading file : ' . $dest_path . '/' . $_FILES['files']['name']['sourcefile1'], 'error');
		}
	} //$_FILES['files']['name']['sourcefile1']
	/* handle result1 file */
	$cur_file_id = $form_state['values']['cur_result1_file_id'];
	if ($cur_file_id > 0)
	{
		/*$file_q = db_query("SELECT * FROM  {textbook_companion_example_files} WHERE id = %d AND example_id = %d", $cur_file_id, $example_data->id);
		$file_data = db_fetch_object($file_q);*/
		$query = db_select('textbook_companion_example_files');
		$query->fields('textbook_companion_example_files');
		$query->condition('id', $cur_file_id);
		$query->condition('example_id', $example_data->id);
		$result = $query->execute();
		$file_data = $result->fetchObject();
		if (!$file_data)
		{
			drupal_set_message("Error deleting example result 1 file. File not present in database.", 'error');
			return;
		} //!$file_data
		if (($form_state['values']['cur_result1_checkbox'] == 1) && (!$_FILES['files']['name']['result1']))
		{
			if (!delete_file($cur_file_id))
			{
				drupal_set_message("Error deleting example result 1 file.", 'error');
				return;
			} //!delete_file($cur_file_id)
		} //($form_state['values']['cur_result1_checkbox'] == 1) && (!$_FILES['files']['name']['result1'])
	} //$cur_file_id > 0
	if ($_FILES['files']['name']['result1'])
	{
		if ($cur_file_id > 0)
		{
			if (!delete_file($cur_file_id))
			{
				drupal_set_message("Error removing previous example result 1 file.", 'error');
				return;
			} //!delete_file($cur_file_id)
		} //$cur_file_id > 0
		if (file_exists($root_path . $dest_path . $_FILES['files']['name']['result1']))
		{
			drupal_set_message(t("Error uploading result 1 file. File !filename already exists.", array(
				'!filename' => $_FILES['files']['name']['result1']
			)), 'error');
			return;
		} //file_exists($root_path . $dest_path . $_FILES['files']['name']['result1'])
		/* uploading file */
		if (move_uploaded_file($_FILES['files']['tmp_name']['result1'], $root_path . $dest_path . $_FILES['files']['name']['result1']))
		{
			/* for uploaded files making an entry in the database */
			/*db_query("INSERT INTO {textbook_companion_example_files} (example_id, filename, filepath, filemime, filesize, filetype, timestamp)
			VALUES (%d, '%s', '%s', '%s', %d, '%s', %d)",
			$example_data->id,
			$_FILES['files']['name']['result1'],
			$dest_path . $_FILES['files']['name']['result1'],
			$_FILES['files']['type']['result1'],
			$_FILES['files']['size']['result1'],
			'R',
			time()
			);*/
			$query = "INSERT INTO {textbook_companion_example_files} (example_id, filename, filepath, filemime, filesize, filetype, 		timestamp) VALUES (:example_id, :filename, :filepath, :filemime, :filesize, :filetype,:timestamp)";
			$args = array(
				":example_id" => $example_data->id,
				":filename" => $_FILES['files']['name']['result1'],
				":filepath" => $dest_path . $_FILES['files']['name']['result1'],
				":filemime" => $_FILES['files']['type']['result1'],
				":filesize" => $_FILES['files']['size']['result1'],
				":filetype" => 'R',
				":timestamp" => time()
			);
			$result = db_query($query, $args, array(
				'return' => Database::RETURN_INSERT_ID
			));
			drupal_set_message($_FILES['files']['name']['result1'] . ' uploaded successfully.', 'status');
		} //move_uploaded_file($_FILES['files']['tmp_name']['result1'], $root_path . $dest_path . $_FILES['files']['name']['result1'])
		else
		{
			drupal_set_message('Error uploading file : ' . $dest_path . '/' . $_FILES['files']['name']['result1'], 'error');
		}
	} //$_FILES['files']['name']['result1']
	/* handle result2 file */
	$cur_file_id = $form_state['values']['cur_result2_file_id'];
	if ($cur_file_id > 0)
	{
		/*$file_q = db_query("SELECT * FROM  {textbook_companion_example_files} WHERE id = %d AND example_id = %d", $cur_file_id, $example_data->id);
		$file_data = db_fetch_object($file_q);*/
		$query = db_select('textbook_companion_example_files');
		$query->fields('textbook_companion_example_files');
		$query->condition('id', $cur_file_id);
		$query->condition('example_id', $example_data->id);
		$result = $query->execute();
		$file_data = $result->fetchObject();
		if (!$file_data)
		{
			drupal_set_message("Error deleting example result 2 file. File not present in database.", 'error');
			return;
		} //!$file_data
		if (($form_state['values']['cur_result2_checkbox'] == 1) && (!$_FILES['files']['name']['result2']))
		{
			if (!delete_file($cur_file_id))
			{
				drupal_set_message("Error deleting example result 2 file.", 'error');
				return;
			} //!delete_file($cur_file_id)
		} //($form_state['values']['cur_result2_checkbox'] == 1) && (!$_FILES['files']['name']['result2'])
	} //$cur_file_id > 0
	if ($_FILES['files']['name']['result2'])
	{
		if ($cur_file_id > 0)
		{
			if (!delete_file($cur_file_id))
			{
				drupal_set_message("Error removing previous example result 2 file.", 'error');
				return;
			} //!delete_file($cur_file_id)
		} //$cur_file_id > 0
		if (file_exists($root_path . $dest_path . $_FILES['files']['name']['result2']))
		{
			drupal_set_message(t("Error uploading result 2 file. File !filename already exists.", array(
				'!filename' => $_FILES['files']['name']['result2']
			)), 'error');
			return;
		} //file_exists($root_path . $dest_path . $_FILES['files']['name']['result2'])
		/* uploading file */
		if (move_uploaded_file($_FILES['files']['tmp_name']['result2'], $root_path . $dest_path . $_FILES['files']['name']['result2']))
		{
			/* for uploaded files making an entry in the database */
			/*db_query("INSERT INTO {textbook_companion_example_files} (example_id, filename, filepath, filemime, filesize, filetype, timestamp)
			VALUES (%d, '%s', '%s', '%s', %d, '%s', %d)",
			$example_data->id,
			$_FILES['files']['name']['result2'],
			$dest_path . $_FILES['files']['name']['result2'],
			$_FILES['files']['type']['result2'],
			$_FILES['files']['size']['result2'],
			'R',
			time()
			);*/
			$query = "INSERT INTO {textbook_companion_example_files} (example_id, filename, filepath, filemime, filesize, filetype, 		timestamp) VALUES (:example_id, :filename, :filepath, :filemime, :filesize, :filetype,:timestamp)";
			$args = array(
				":example_id" => $example_data->id,
				":filename" => $_FILES['files']['name']['result2'],
				":filepath" => $dest_path . $_FILES['files']['name']['result2'],
				":filemime" => $_FILES['files']['type']['result2'],
				":filesize" => $_FILES['files']['size']['result2'],
				":filetype" => 'R',
				":timestamp" => time()
			);
			$result = db_query($query, $args, array(
				'return' => Database::RETURN_INSERT_ID
			));
			drupal_set_message($_FILES['files']['name']['result2'] . ' uploaded successfully.', 'status');
		} //move_uploaded_file($_FILES['files']['tmp_name']['result2'], $root_path . $dest_path . $_FILES['files']['name']['result2'])
		else
		{
			drupal_set_message('Error uploading file : ' . $dest_path . '/' . $_FILES['files']['name']['result2'], 'error');
		}
	} //$_FILES['files']['name']['result2']
	/* handle xcos1 file */
	$cur_file_id = $form_state['values']['cur_xcos1_file_id'];
	if ($cur_file_id > 0)
	{
		/*$file_q = db_query("SELECT * FROM  {textbook_companion_example_files} WHERE id = %d AND example_id = %d", $cur_file_id, $example_data->id);
		$file_data = db_fetch_object($file_q);*/
		$query = db_select('textbook_companion_example_files');
		$query->fields('textbook_companion_example_files');
		$query->condition('id', $cur_file_id);
		$query->condition('example_id', $example_data->id);
		$result = $query->execute();
		$file_data = $result->fetchObject();
		if (!$file_data)
		{
			drupal_set_message("Error deleting example xcos 1 file. File not present in database.", 'error');
			return;
		} //!$file_data
		if (($form_state['values']['cur_xcos1_checkbox'] == 1) && (!$_FILES['files']['name']['xcos1']))
		{
			if (!delete_file($cur_file_id))
			{
				drupal_set_message("Error deleting example xcos 1 file.", 'error');
				return;
			} //!delete_file($cur_file_id)
		} //($form_state['values']['cur_xcos1_checkbox'] == 1) && (!$_FILES['files']['name']['xcos1'])
	} //$cur_file_id > 0
	if ($_FILES['files']['name']['xcos1'])
	{
		if ($cur_file_id > 0)
		{
			if (!delete_file($cur_file_id))
			{
				drupal_set_message("Error removing previous example xcos 1 file.", 'error');
				return;
			} //!delete_file($cur_file_id)
		} //$cur_file_id > 0
		if (file_exists($root_path . $dest_path . $_FILES['files']['name']['xcos1']))
		{
			drupal_set_message(t("Error uploading xcos 1 file. File !filename already exists.", array(
				'!filename' => $_FILES['files']['name']['xcos1']
			)), 'error');
			return;
		} //file_exists($root_path . $dest_path . $_FILES['files']['name']['xcos1'])
		/* uploading file */
		if (move_uploaded_file($_FILES['files']['tmp_name']['xcos1'], $root_path . $dest_path . $_FILES['files']['name']['xcos1']))
		{
			/* for uploaded files making an entry in the database */
			/*db_query("INSERT INTO {textbook_companion_example_files} (example_id, filename, filepath, filemime, filesize, filetype, timestamp)
			VALUES (%d, '%s', '%s', '%s', %d, '%s', %d)",
			$example_data->id,
			$_FILES['files']['name']['xcos1'],
			$dest_path . $_FILES['files']['name']['xcos1'],
			$_FILES['files']['type']['xcos1'],
			$_FILES['files']['size']['xcos1'],
			'X',
			time()
			);*/
			$query = "INSERT INTO {textbook_companion_example_files} (example_id, filename, filepath, filemime, filesize, filetype, 		timestamp) VALUES (:example_id, :filename, :filepath, :filemime, :filesize, :filetype,:timestamp)";
			$args = array(
				":example_id" => $example_data->id,
				":filename" => $_FILES['files']['name']['xcos1'],
				":filepath" => $dest_path . $_FILES['files']['name']['xcos1'],
				":filemime" => $_FILES['files']['type']['xcos1'],
				":filesize" => $_FILES['files']['size']['xcos1'],
				":filetype" => 'X',
				":timestamp" => time()
			);
			$result = db_query($query, $args, array(
				'return' => Database::RETURN_INSERT_ID
			));
			drupal_set_message($_FILES['files']['name']['xcos1'] . ' uploaded successfully.', 'status');
		} //move_uploaded_file($_FILES['files']['tmp_name']['xcos1'], $root_path . $dest_path . $_FILES['files']['name']['xcos1'])
		else
		{
			drupal_set_message('Error uploading file : ' . $dest_path . '/' . $_FILES['files']['name']['xcos1'], 'error');
		}
	} //$_FILES['files']['name']['xcos1']
	/* handle xcos2 file */
	$cur_file_id = $form_state['values']['cur_xcos2_file_id'];
	if ($cur_file_id > 0)
	{
		/*$file_q = db_query("SELECT * FROM  {textbook_companion_example_files} WHERE id = %d AND example_id = %d", $cur_file_id, $example_data->id);
		$file_data = db_fetch_object($file_q);*/
		$query = db_select('textbook_companion_example_files');
		$query->fields('textbook_companion_example_files');
		$query->condition('id', $cur_file_id);
		$query->condition('example_id', $example_data->id);
		$result = $query->execute();
		$file_data = $result->fetchObject();
		if (!$file_data)
		{
			drupal_set_message("Error deleting example xcos 2 file. File not present in database.", 'error');
			return;
		} //!$file_data
		if (($form_state['values']['cur_xcos2_checkbox'] == 1) && (!$_FILES['files']['name']['xcos2']))
		{
			if (!delete_file($cur_file_id))
			{
				drupal_set_message("Error deleting example xcos 2 file.", 'error');
				return;
			} //!delete_file($cur_file_id)
		} //($form_state['values']['cur_xcos2_checkbox'] == 1) && (!$_FILES['files']['name']['xcos2'])
	} //$cur_file_id > 0
	if ($_FILES['files']['name']['xcos2'])
	{
		if ($cur_file_id > 0)
		{
			if (!delete_file($cur_file_id))
			{
				drupal_set_message("Error removing previous example xcos 2 file.", 'error');
				return;
			} //!delete_file($cur_file_id)
		} //$cur_file_id > 0
		if (file_exists($root_path . $dest_path . $_FILES['files']['name']['xcos2']))
		{
			drupal_set_message(t("Error uploading xcos 2 file. File !filename already exists.", array(
				'!filename' => $_FILES['files']['name']['xcos2']
			)), 'error');
			return;
		} //file_exists($root_path . $dest_path . $_FILES['files']['name']['xcos2'])
		/* uploading file */
		if (move_uploaded_file($_FILES['files']['tmp_name']['xcos2'], $root_path . $dest_path . $_FILES['files']['name']['xcos2']))
		{
			/* for uploaded files making an entry in the database */
			/*db_query("INSERT INTO {textbook_companion_example_files} (example_id, filename, filepath, filemime, filesize, filetype, timestamp)
			VALUES (%d, '%s', '%s', '%s', %d, '%s', %d)",
			$example_data->id,
			$_FILES['files']['name']['xcos2'],
			$dest_path . $_FILES['files']['name']['xcos2'],
			$_FILES['files']['type']['xcos2'],
			$_FILES['files']['size']['xcos2'],
			'X',
			time()
			);*/
			$query = "INSERT INTO {textbook_companion_example_files} (example_id, filename, filepath, filemime, filesize, filetype, 		timestamp) VALUES (:example_id, :filename, :filepath, :filemime, :filesize, :filetype,:timestamp)";
			$args = array(
				":example_id" => $example_data->id,
				":filename" => $_FILES['files']['name']['xcos2'],
				":filepath" => $dest_path . $_FILES['files']['name']['xcos2'],
				":filemime" => $_FILES['files']['type']['xcos2'],
				":filesize" => $_FILES['files']['size']['xcos2'],
				":filetype" => 'X',
				":timestamp" => time()
			);
			$result = db_query($query, $args, array(
				'return' => Database::RETURN_INSERT_ID
			));
			drupal_set_message($_FILES['files']['name']['xcos2'] . ' uploaded successfully.', 'status');
		} //move_uploaded_file($_FILES['files']['tmp_name']['xcos2'], $root_path . $dest_path . $_FILES['files']['name']['xcos2'])
		else
		{
			drupal_set_message('Error uploading file : ' . $dest_path . '/' . $_FILES['files']['name']['xcos2'], 'error');
		}
	} //$_FILES['files']['name']['xcos2']
	/* sending email */
	$email_to = $user->mail;
	$param['example_updated']['example_id'] = $example_id;
	$param['example_updated']['user_id'] = $user->uid;
	if (!drupal_mail('textbook_companion', 'example_updated', $email_to, language_default(), $param, variable_get('textbook_companion_from_email', NULL), TRUE))
		drupal_set_message('Error sending email message.', 'error');
	drupal_set_message(t("Example successfully udpated."), 'status');
}
/******************************************************************************/
/**************************** EDIT CHAPTER TITLE ******************************/
/******************************************************************************/
function edit_chapter_title_form($form_state)
{
	global $user;
	/************************ start approve book details ************************/
	/*$proposal_q = db_query("SELECT * FROM {textbook_companion_proposal} WHERE uid = %d ORDER BY id DESC LIMIT 1", $user->uid);
	$proposal_data = db_fetch_object($proposal_q);*/
	$query = db_select('textbook_companion_proposal');
	$query->fields('textbook_companion_proposal');
	$query->condition('uid', $user->uid);
	$query->orderBy('id', 'DESC');
	$query->range(0, 1);
	$result = $query->execute();
	$proposal_data = $result->fetchObject();
	if (!$proposal_data)
	{
		drupal_set_message("Please submit a " . l('proposal', 'proposal') . ".", 'error');
		drupal_goto('textbook_companion/code');
	} //!$proposal_data
	if ($proposal_data->proposal_status != 1 && $proposal_data->proposal_status != 4)
	{
		switch ($proposal_data->proposal_status)
		{
			case 0:
				drupal_set_message(t('We have already received your proposal. We will get back to you soon.'), 'status');
				drupal_goto('textbook_companion/code');
				return;
				break;
			case 2:
				drupal_set_message(t('Your proposal has been dis-approved. Please create another proposal ' . l('here', 'proposal') . '.'), 'error');
				drupal_goto('textbook_companion/code');
				return;
				break;
			case 3:
				drupal_set_message(t('Congratulations! You have completed your last book proposal. You have to create another proposal ' . l('here', 'proposal') . '.'), 'status');
				drupal_goto('textbook_companion/code');
				return;
				break;
			default:
				drupal_set_message(t('Invalid proposal state. Please contact site administrator for further information.'), 'error');
				drupal_goto('textbook_companion/code');
				return;
				break;
		} //$proposal_data->proposal_status
	} //$proposal_data->proposal_status != 1 && $proposal_data->proposal_status != 4
	/*$preference_q = db_query("SELECT * FROM {textbook_companion_preference} WHERE proposal_id = %d AND approval_status = 1 LIMIT 1", $proposal_data->id);
	$preference_data = db_fetch_object($preference_q);*/
	$query = db_select('textbook_companion_preference');
	$query->fields('textbook_companion_preference');
	$query->condition('proposal_id', $proposal_data->id);
	$query->condition('approval_status', 1);
	$query->range(0, 1);
	$result = $query->execute();
	$preference_data = $result->fetchObject();
	if (!$preference_data)
	{
		drupal_set_message(t('Invalid Book Preference status. Please contact site administrator for further information.'), 'error');
		drupal_goto('textbook_companion/code');
		return;
	} //!$preference_data
	/************************ end approve book details **************************/
	$chapter_id = arg(4);
	/*$chapter_q = db_query("SELECT * FROM {textbook_companion_chapter} WHERE id = %d AND preference_id = %d", $chapter_id, $preference_data->id);
	$chapter_data = db_fetch_object($chapter_q);*/
	$query = db_select('textbook_companion_chapter');
	$query->fields('textbook_companion_chapter');
	$query->condition('id', $chapter_id);
	$query->condition('preference_id', $preference_data->id);
	$result = $query->execute();
	$chapter_data = $result->fetchObject();
	if (!$chapter_data)
	{
		drupal_set_message(t('Invalid chapter.'), 'error');
		drupal_goto('textbook_companion/code');
		return;
	} //!$chapter_data
	$form['#redirect'] = 'textbook_companion/code';
	$form['book_details']['book'] = array(
		'#type' => 'item',
		'#markup' => $preference_data->book,
		'#title' => t('Title of the Book')
	);
	$form['contributor_name'] = array(
		'#type' => 'item',
		'#markup' => $proposal_data->full_name,
		'#title' => t('Contributor Name')
	);
	$form['number'] = array(
		'#type' => 'item',
		'#title' => t('Chapter No'),
		'#markup' => $chapter_data->number
	);
	$form['chapter_title'] = array(
		'#type' => 'textfield',
		'#title' => t('Title of the Chapter'),
		'#size' => 40,
		'#maxlength' => 255,
		'#required' => TRUE,
		'#default_value' => $chapter_data->name
	);
	$form['submit'] = array(
		'#type' => 'submit',
		'#value' => t('Submit')
	);
	$form['cancel'] = array(
		'#type' => 'markup',
		'#value' => l(t('Cancel'), 'textbook_companion/code')
	);
	return $form;
}
function edit_chapter_title_form_validate($form, &$form_state)
{
	if (!check_name($form_state['values']['chapter_title']))
		form_set_error('chapter_title', t('Title of the Chapter can contain only alphabets, numbers and spaces.'));
}
function edit_chapter_title_form_submit($form, &$form_state)
{
	global $user;
	/************************ start approve book details ************************/
	/*$proposal_q = db_query("SELECT * FROM {textbook_companion_proposal} WHERE uid = %d ORDER BY id DESC LIMIT 1", $user->uid);
	$proposal_data = db_fetch_object($proposal_q);*/
	$query = db_select('textbook_companion_proposal');
	$query->fields('textbook_companion_proposal');
	$query->condition('uid', $user->uid);
	$query->orderBy('id', 'DESC');
	$query->range(0, 1);
	$result = $query->execute();
	$proposal_data = $result->fetchObject();
	if (!$proposal_data)
	{
		drupal_set_message("Please submit a " . l('proposal', 'proposal') . ".", 'error');
		drupal_goto('textbook_companion/code');
	} //!$proposal_data
	if ($proposal_data->proposal_status != 1 && $proposal_data->proposal_status != 4)
	{
		switch ($proposal_data->proposal_status)
		{
			case 0:
				drupal_set_message(t('We have already received your proposal. We will get back to you soon.'), 'status');
				drupal_goto('textbook_companion/code');
				return;
				break;
			case 2:
				drupal_set_message(t('Your proposal has been dis-approved. Please create another proposal ' . l('here', 'proposal') . '.'), 'error');
				drupal_goto('textbook_companion/code');
				return;
				break;
			case 3:
				drupal_set_message(t('Congratulations! You have completed your last book proposal. You have to create another proposal ' . l('here', 'proposal') . '.'), 'status');
				drupal_goto('textbook_companion/code');
				return;
				break;
			default:
				drupal_set_message(t('Invalid proposal state. Please contact site administrator for further information.'), 'error');
				drupal_goto('textbook_companion/code');
				return;
				break;
		} //$proposal_data->proposal_status
	} //$proposal_data->proposal_status != 1 && $proposal_data->proposal_status != 4
	/*$preference_q = db_query("SELECT * FROM {textbook_companion_preference} WHERE proposal_id = %d AND approval_status = 1 LIMIT 1", $proposal_data->id);
	$preference_data = db_fetch_object($preference_q);*/
	$query = db_select('textbook_companion_preference');
	$query->fields('textbook_companion_preference');
	$query->condition('proposal_id', $proposal_data->id);
	$query->condition('approval_status', 1);
	$query->range(0, 1);
	$result = $query->execute();
	$preference_data = $result->fetchObject();
	if (!$preference_data)
	{
		drupal_set_message(t('Invalid Book Preference status. Please contact site administrator for further information.'), 'error');
		drupal_goto('textbook_companion/code');
		return;
	} //!$preference_data
	/************************ end approve book details **************************/
	$chapter_id = arg(4);
	/*$chapter_q = db_query("SELECT * FROM {textbook_companion_chapter} WHERE id = %d AND preference_id = %d", $chapter_id, $preference_data->id);
	$chapter_data = db_fetch_object($chapter_q);*/
	$query = db_select('textbook_companion_chapter');
	$query->fields('textbook_companion_chapter');
	$query->condition('id', $chapter_id);
	$query->condition('preference_id', $preference_data->id);
	$result = $query->execute();
	$chapter_data = $result->fetchObject();
	if (!$chapter_data)
	{
		drupal_set_message(t('Invalid chapter.'), 'error');
		drupal_goto('textbook_companion/code');
		return;
	} //!$chapter_data
	/*db_query("UPDATE {textbook_companion_chapter} SET name = '%s' WHERE id = %d", $form_state['values']['chapter_title'], $chapter_id);*/
	$query = db_update('textbook_companion_chapter');
	$query->fields(array(
		'name' => $form_state['values']['chapter_title']
	));
	$query->condition('id', $chapter_id);
	$num_updated = $query->execute();
	drupal_set_message(t('Title of the Chapter updated.'), 'status');
	drupal_goto('textbook_companion/code');
}
/******************************************************************************/
/************************** GENERAL FUNCTIONS *********************************/
/******************************************************************************/
function _list_of_book_titles()
{
	$book_titles = array(
		'0' => 'Please select...'
	);
	/*$book_titles_q = db_query("SELECT * FROM {textbook_companion_preference} WHERE approval_status = 1 OR approval_status = 3 ORDER BY book ASC");*/
	$query = db_select('textbook_companion_preference');
	$query->fields('textbook_companion_preference');
	$or = db_or();
	$or->condition('approval_status', 1);
	$or->condition('approval_status', 3);
	$query->condition($or);
	$query->orderBy('book', 'ASC');
	$book_titles_q = $query->execute();
	while ($book_titles_data = $book_titles_q->fetchObject())
	{
		$book_titles[$book_titles_data->id] = $book_titles_data->book . ' (Written by ' . $book_titles_data->author . ')';
	} //$book_titles_data = $book_titles_q->fetchObject()
	return $book_titles;
}
function _list_of_book_dependency_files()
{
	$book_dependency_files = array();
	$book_dependency_files_class = array();
	/*$book_dependency_files_q = db_query("SELECT * FROM {textbook_companion_dependency_files} ORDER BY filename ASC");*/
	$query = db_select('textbook_companion_dependency_files', 'tcdp');
	$query->fields('tcdp');
	$query->fields('tcp', array(
		'book',
		'author',
		'publisher',
		'edition',
		'year'
	));
	$query->leftJoin('textbook_companion_preference', 'tcp', 'tcdp.preference_id = tcp.id');
	$book_dependency_files_q = $query->execute();
	while ($book_dependency_files_data = $book_dependency_files_q->fetchObject())
	{
		$temp_caption = '';
		if ($book_dependency_files_data->caption)
			$temp_caption .= ' ===>[Caption: ' . $book_dependency_files_data->caption . ' ' . ', Book: ' . $book_dependency_files_data->book . ', Author: ' . $book_dependency_files_data->author . ', Publisher: ' . $book_dependency_files_data->publisher . ', Edition: ' . $book_dependency_files_data->edition . ', Year: ' . $book_dependency_files_data->year . ']';
		$book_dependency_files[$book_dependency_files_data->id] = l($book_dependency_files_data->filename, 'download/dependency/' . $book_dependency_files_data->id, array(
			'attributes' => array(
				'class' => 'title'
			)
		)) . $temp_caption;
		$book_dependency_files_class[$book_dependency_files_data->id] = $book_dependency_files_data->preference_id;
	} //$book_dependency_files_data = $book_dependency_files_q->fetchObject()
	return array(
		$book_dependency_files,
		$book_dependency_files_class
	);
}