Create custom php stow app

stow

@@ -0,0 +1,85 @@
+#!/usr/bin/env php
+<?php
+
+function path(...$segments): string
+{
+    return join(DIRECTORY_SEPARATOR, $segments);
+}
+
+function line(string $line): void
+{
+    echo $line . PHP_EOL;
+}
+
+$cwd = getcwd();
+$action = 'stow';
+$backup = $force = false;
+array_shift($argv); // we don't care about the script name
+
+while (str_starts_with($argv[0], '-')) {
+    $option = substr($argv[0], 1);
+    switch ($option) {
+        case 'u':
+            $action = 'unstow';
+            break;
+        case 'b':
+            $backup = true;
+            break;
+        case 'f':
+            $force = true;
+            break;
+        default:
+            line("Unknown option: $option");
+            exit(1);
+    }
+    array_shift($argv);
+}
+
+$stowName = $argv[0];
+$stowPath = path($cwd, $stowName);
+$targetPath = dirname($stowPath, 2);
+
+if (!is_dir($stowPath)) {
+    line("Directory '$stowName' does not exist");
+    exit(1);
+}
+
+$files = array_diff(scandir($stowPath), ['..', '.']);
+
+foreach ($files as $file) {
+    $targetFile = path($targetPath, $file);
+    $stowFile = path($stowPath, $file);
+    $isStowed = is_link($targetFile) && readlink($targetFile) === $stowFile;
+
+    if ($action === 'stow') {
+        if (is_link($targetFile)) {
+            line("File $targetFile is already stowed from $stowFile");
+            continue;
+        }
+        if (is_file($targetFile)) {
+            if ($backup) {
+                $backFile = $targetFile . '.bak';
+                if (is_file($backFile)) {
+                    line("Backup file $backFile already exists");
+                    continue;
+                }
+                rename($targetFile, $backFile);
+                line("Backup file $targetFile to $backFile");
+            } elseif ($force) {
+                line("Todo: delete file $targetFile");
+                continue;
+            } else {
+                line("File $targetFile already exists");
+                continue;
+            }
+        }
+        line("Stow $stowFile to $targetFile");
+        symlink($stowFile, $targetFile);
+    } elseif ($action === 'unstow') {
+        if (!$isStowed) {
+            line("File $targetFile is not stowed from $stowFile");
+            continue;
+        }
+        unlink($targetFile);
+    }
+}