find and replace feature (#15)

Signed-off-by: rahul <[email protected]>

Author: rcsofttech85

src/FileHandler.php

@@ -13,6 +13,7 @@ class FileHandler
 
     private array $files = [];
 
+
     /**
      * @throws FileHandlerException
      */
@@ -160,31 +161,44 @@ public function delete(string $filename): void
     /**
      * @throws FileHandlerException
      */
-    private function getRows(): Generator
+    private function getRows(string|null $filename = null): Generator
     {
-        if (count($this->files) > 1) {
-            throw new FileHandlerException("multiple files not allowed");
-        }
-
-        $file = $this->files[0];
-        $headers = fgetcsv($file);
-
-        $this->isValidCsvFileFormat($headers);
+        $file = $this->ensureSingleFileProcessing($filename);
+        $headers = $this->extractHeader($file);
 
         $isEmptyFile = true;
-        while (($row = fgetcsv($file)) !== false) {
-            $isEmptyFile = false;
-            $this->isValidCsvFileFormat($row);
-            $item = array_combine($headers, $row);
-            yield $item;
+        try {
+            while (($row = fgetcsv($file)) !== false) {
+                $isEmptyFile = false;
+                $this->isValidCsvFileFormat($row);
+                $item = array_combine($headers, $row);
+
+                yield $item;
+            }
+        } finally {
+            fclose($file);
         }
-        fclose($file);
+
 
         if ($isEmptyFile) {
             throw new FileHandlerException('invalid file format');
         }
     }
 
+    private function ensureSingleFileProcessing(string|null $filename): mixed
+    {
+        if (count($this->files) < 1) {
+            if (!$filename || !file_exists($filename)) {
+                throw new FileHandlerException("no files to process");
+            }
+            $this->open($filename);
+        }
+        if (count($this->files) > 1) {
+            throw new FileHandlerException("multiple files not allowed");
+        }
+        return $this->files[0];
+    }
+
     /**
      * @throws FileHandlerException
      */
@@ -198,6 +212,100 @@ private function search(string $keyword, string $column, string|null $format): b
         return false;
     }
 
+    public function findAndReplaceInCsv(
+        string $filename,
+        string $keyword,
+        string $replace,
+        string|null $column = null
+    ): bool {
+        $headers = $this->extractHeader($filename);
+
+
+        if (!$headers) {
+            throw new FileHandlerException('failed to extract header');
+        }
+
+        $tempFilePath = $this->createTempFileWithHeaders($headers);
+
+        try {
+            $count = 0;
+            foreach ($this->getRows($filename) as $row) {
+                if (!$column) {
+                    $count += $this->replaceKeywordInRow($row, $keyword, $replace);
+                } else {
+                    $count += $this->replaceKeywordInColumn($row, $column, $keyword, $replace);
+                }
+
+                $this->writeRowToTempFile($tempFilePath, $row);
+            }
+
+            if ($count < 1) {
+                return false;
+            }
+
+            $this->renameTempFile($tempFilePath, $filename);
+        } finally {
+            $this->cleanupTempFile($tempFilePath);
+        }
+
+        return true;
+    }
+
+    private function replaceKeywordInRow(array &$row, string $keyword, string $replace): int
+    {
+        $count = 0;
+        $replacement = array_search($keyword, $row);
+
+        if ($replacement !== false) {
+            $row[$replacement] = $replace;
+            $count++;
+        }
+
+        return $count;
+    }
+
+    private function replaceKeywordInColumn(array &$row, string $column, string $keyword, string $replace): int
+    {
+        $count = 0;
+
+        if ($keyword === $row[$column]) {
+            $row[$column] = $replace;
+            $count++;
+        }
+
+        return $count;
+    }
+
+    private function writeRowToTempFile(string $tempFilePath, array $row): void
+    {
+        $tempFileHandle = fopen($tempFilePath, 'a');
+        fputs($tempFileHandle, implode(',', $row) . PHP_EOL);
+        fclose($tempFileHandle);
+    }
+
+    private function renameTempFile(string $tempFilePath, string $filename): void
+    {
+        if (!rename($tempFilePath, $filename)) {
+            throw new FileHandlerException('Failed to rename temp file');
+        }
+    }
+
+    private function cleanupTempFile(string $tempFilePath): void
+    {
+        unlink($tempFilePath);
+    }
+
+    private function createTempFileWithHeaders(array $headers): string
+    {
+        $tempFilePath = tempnam(sys_get_temp_dir(), 'tempfile_');
+        $tempFileHandle = fopen($tempFilePath, 'w');
+        fputs($tempFileHandle, implode(',', $headers) . PHP_EOL);
+        fclose($tempFileHandle);
+
+        return $tempFilePath;
+    }
+
+
     /**
      * @throws FileHandlerException
      */
@@ -207,4 +315,28 @@ private function isValidCsvFileFormat(array|false $row): void
             throw new FileHandlerException('invalid file format');
         }
     }
+
+    private function extractHeader(mixed $file): array|false
+    {
+        if (is_resource($file)) {
+            $headers = fgetcsv($file);
+        }
+        if (is_string($file)) {
+            if (!file_exists($file)) {
+                return false;
+            }
+            try {
+                $file = fopen($file, 'r');
+                $headers = fgetcsv($file);
+            } finally {
+                fclose($file);
+            }
+        }
+
+        if ($this->isValidCsvFileFormat($headers) !== false) {
+            return $headers;
+        }
+
+        return false;
+    }
 }

tests/unit/FileHandlerTest.php

@@ -80,6 +80,7 @@ public function shouldThrowExceptionIfFileIsNotWritable()
         $this->expectException(FileHandlerException::class);
         $this->expectExceptionMessage('Error writing to file');
         $this->fileHandler->write(data: "hello world");
+        $this->fileHandler->close();
     }
 
 
@@ -107,6 +108,7 @@ public function multipleFileCanBeWrittenSimultaneously()
         $this->assertEquals("hello world", file_get_contents(filename: 'file'));
 
         $this->assertEquals("hello world", file_get_contents(filename: 'file1'));
+        $this->fileHandler->close();
     }
 
 
@@ -252,6 +254,37 @@ public function throwErrorIfFileFormatIsInvalid(string $file)
         }
     }
 
+    #[Test]
+    public function findAndReplaceInCsvMethodShouldReplaceTextUsingColumnOption()
+    {
+        $fileHandler = new FileHandler();
+
+        $hasReplaced = $fileHandler->findAndReplaceInCsv("movie.csv", "Twilight", "Inception", "Film");
+
+        $this->assertTrue($hasReplaced);
+
+
+        $data = $this->fileHandler->open("movie.csv")->searchInCsvFile("Inception", "Film", FileHandler::ARRAY_FORMAT);
+
+        $this->assertEquals($data["Film"], "Inception");
+    }
+
+    #[Test]
+    public function findAndReplaceInCsvMethodShouldReplaceTextWithoutColumnOption()
+    {
+        $fileHandler = new FileHandler();
+
+
+        $hasReplaced = $fileHandler->findAndReplaceInCsv("movie.csv", "Inception", "Twilight");
+
+        $this->assertTrue($hasReplaced);
+
+
+        $data = $this->fileHandler->open("movie.csv")->searchInCsvFile("Twilight", "Film", FileHandler::ARRAY_FORMAT);
+
+        $this->assertEquals($data["Film"], "Twilight");
+    }
+
     //  Data Providers
 
     public static function provideStudioNames(): iterable