import re

file_path = 'includes/actions.php'

try:
    with open(file_path, 'r') as f:
        content = f.read()
except FileNotFoundError:
    print(f"Error: {file_path} not found.")
    exit(1)

# New function implementation
new_function = r"""    function parse_import_file($file_input) {
        if (!isset($file_input['error']) || $file_input['error'] !== UPLOAD_ERR_OK) {
            $_SESSION['import_error'] = 'Upload error code: ' . ($file_input['error'] ?? 'unknown');
            return false;
        }
        $ext = strtolower(pathinfo($file_input['name'], PATHINFO_EXTENSION));
        $rows = [];
        
        if ($ext === 'csv') {
            $handle = fopen($file_input['tmp_name'], 'r');
            if ($handle === false) {
                $_SESSION['import_error'] = 'Failed to open CSV file.';
                return false;
            }
            # Skip header
            fgetcsv($handle);
            while (($row = fgetcsv($handle)) !== false) {
                if (array_filter($row)) {
                    $rows[] = $row;
                }
            }
            fclose($handle);
            if (empty($rows)) {
                 $_SESSION['import_error'] = 'CSV file is empty or could not be parsed.';
            }
        } elseif ($ext === 'xlsx' || $ext === 'xls') {
            require_once __DIR__ . '/SimpleXLSX.php';
            if ($xlsx = \Shuchkin\SimpleXLSX::parse($file_input['tmp_name'])) {
                $rows = $xlsx->rows();
                array_shift($rows); # Skip header
                if (empty($rows)) {
                    $_SESSION['import_error'] = 'Excel file is empty.';
                }
            } else {
                $_SESSION['import_error'] = 'SimpleXLSX Error: ' . \Shuchkin\SimpleXLSX::parseError();
                return false;
            }
        } else {
            $_SESSION['import_error'] = "Unsupported file extension: $ext. Please upload .csv or .xlsx";
            return false;
        }
        return $rows;
    }"""

# Escape specific regex characters in the new function if we used it in regex, but here we use it as replacement string.
# We need to escape backslashes in the replacement string if we use re.sub, because \1, \g<1> etc have meaning.
# However, our replacement string doesn't have those. But PHP has backslashes (namespaces).
# So we need to escape backslashes for python string, and then for re.sub.

# Actually, let's use string.replace() if possible, but we don't know the exact content of the old function to replace it exactly if it varies.
# But we know the structure.
# Let's try to identify the start and end of the function.

start_marker = "function parse_import_file($file_input) {"
end_marker = "return $rows;\n    }"

start_pos = content.find(start_marker)
if start_pos != -1:
    end_pos = content.find(end_marker, start_pos)
    if end_pos != -1:
        end_pos += len(end_marker)
        # Replace the function
        content = content[:start_pos] + new_function.strip() + "\n" + content[end_pos:]
        print("Replaced function parse_import_file.")
    else:
        print("Could not find end of function parse_import_file.")
        # Fallback to regex if simple find fails (e.g. whitespace diff)
        pattern = r"function parse_import_file\(\$file_input\) \{[\s\S]+?return \$rows;\s+\}"
        if re.search(pattern, content):
             content = re.sub(pattern, new_function, content, count=1)
             print("Replaced function parse_import_file using regex.")
        else:
             print("Could not find function parse_import_file using regex.")
else:
    print("Could not find start of function parse_import_file.")
    # Fallback to regex
    pattern = r"function parse_import_file\(\$file_input\) \{[\s\S]+?return \$rows;\s+\}"
    if re.search(pattern, content):
         content = re.sub(pattern, new_function, content, count=1)
         print("Replaced function parse_import_file using regex (fallback).")
    else:
         print("Could not find function parse_import_file using regex (fallback).")


# Update the calling logic
old_msg = "$_SESSION['flash_message'] = 'Failed to parse file or empty.';"
new_msg = "$_SESSION['flash_message'] = $_SESSION['import_error'] ?? 'Failed to parse file or empty.'; unset($_SESSION['import_error']);"

if old_msg in content:
    content = content.replace(old_msg, new_msg)
    print("Updated error message logic.")
else:
    print("Could not find old error message logic.")

with open(file_path, 'w') as f:
    f.write(content)

print("Finished updating includes/actions.php")