I am interested in the 'groups' of records in the source file.
Date group - indicated by the a line with just a date on it
- Store Group - consists of..
- store name
- price
- a group of dates
Added Requirement: print out only store groups that is current date and forward? I will call this the 'cutoff_date' in the code.
I use a 'read-ahead' technique so there is always a record to process
I supply functions to help 'identify things'. They are used so it is easier to see the controlling' logic.
The code:
<?php // https://stackoverflow.com/questions/29121286/extract-information-from-text-file-using-php
/**
* We need to only show store entries on or after a certain date
* i call this the 'cutoff_date'.
*
* It will default to todays date
*/
$now = new DateTime();
$CUTOFF_DATE = $now->format('Y-m-d');
// output stored in here
$outHtml = '<table border="1">
<tr>
<th>Date</th>
<th>Store</th>
<th>Text 1</th>
<th>Text 2</th>
<th>Text 3</th>
</tr>';
// source - we use 'read-ahead' as it makes life easier
$sourceFile = fopen(__DIR__ . '/Q29121286.txt', 'rb');
$currentLine = readNextLine($sourceFile); // read-ahead
while (!empty($currentLine)) { // process until eof...
// start of a date group...
$currentGroupDate = $currentLine; // ignore this group if less than CUTOFF_DATE
$currentLine = readNextLine($sourceFile); // read ahead
while (!empty($currentGroupDate) && $currentGroupDate < $CUTOFF_DATE) { // find next date_group record
while (!empty($currentLine) && datePosition($currentLine) !== 0) { // read to end of current group
$currentLine = readNextLine($sourceFile);
}
$currentGroupDate = $currentLine;
$currentLine = readNextLine($sourceFile); // read ahead
}
$htmlCurrentDate = $currentGroupDate; // only print the date once
$html = '';
// display all the rows for this 'date group' -- look for next 'date'
while (!empty($currentLine) && datePosition($currentLine) !== 0) {
$html = '<tr>';
$html .= '<td>'. $htmlCurrentDate .'</td>';
$htmlCurrentDate = ''; // only display the date once
$html .= '<td>'. $currentLine .'</td>'; // store
$currentLine = readNextLine($sourceFile);
// process the price
$lineParts = explode(':', $currentLine); // need the price...
$html .= '<td>'. $lineParts[1] .'</td>';
$currentLine = readNextLine($sourceFile);
// now process the group of dates - look for a line
// that starts with 'text' and must contain a date
while ( !empty($currentLine)
&& isTextLine($currentLine)
&& datePosition($currentLine) >= 1) {
$lineParts = explode(':', $currentLine); // need the date...
$html .= '<td>'. $lineParts[1] .'</td>';
$currentLine = readNextLine($sourceFile); // read next
}
// end of this group...
$html .= '</tr>';
$outHtml .= $html;
} // end of 'dateGroup'
} // end of data file...
$outHtml .= '</table>';
fclose($sourceFile);
// display output
echo $outHtml;
exit;
/**
* These routines hide the low-level processing;
*/
/**
* Return position of date string - will be -1 if not found
* @param type $line
* @return integer
*/
function datePosition($line)
{
$result = preg_match("/\d{4}-\d{2}-\d{2}/", $line, $matches, PREG_OFFSET_CAPTURE);
$pos = -1;
if (!empty($matches)) {
$match = current($matches);
$pos = $match[1];
}
return $pos;
}
/**
* return whether line is a text line
*
* @param type $text
* @return type
*/
function isTextLine($text)
{
return strpos(strtolower($text), 'text') === 0;
}
/**
* return trimmed string or an empty string at eof
* Added 'fudge' to not read passed the eof - ;-/
* @param type $handle
* @return string
*/
function readNextLine($handle)
{
static $isEOF = false;
if ($isEOF) {
return '';
}
$line = fgets($handle);
if ($line !== false) {
$line = trim($line);
}
else {
$isEOF = true;
$line = '';
}
return $line;
}
Original output from the supplied file:
| Date | Store | Text 1 | Text 2 | Text 3 |
|------------|---------|-----------|------------|------------|
| 2015-03-18 | Store A | 5,00 USD | 2015-03-18 | 2015-03-12 |
| | Store B | 10,00 USD | 2015-03-18 | 2015-03-12 |
| | Store C | 15,00 USD | 2015-03-18 | 2015-03-12 |
| 2015-03-19 | Store D | 20,00 USD | 2015-03-18 | 2015-03-12 |
