Add Introduction markdown file

Pyto.xcodeproj/project.pbxproj

@@ -142,6 +142,7 @@
 		C9E415312151531B00D64E32 /* REPL.py in Resources */ = {isa = PBXBuildFile; fileRef = C9E415302151531B00D64E32 /* REPL.py */; };
 		C9E509A221BC08F900261E3A /* docs in Resources */ = {isa = PBXBuildFile; fileRef = C9E509A121BC08F800261E3A /* docs */; };
 		C9EA55B3219F752D007546BC /* RelativePathForScript.swift in Sources */ = {isa = PBXBuildFile; fileRef = C9EA55B2219F752D007546BC /* RelativePathForScript.swift */; };
+		C9EA5C7D21F23558000F7FA7 /* Welcome to Pyto.md in Resources */ = {isa = PBXBuildFile; fileRef = C9EA5C7C21F23024000F7FA7 /* Welcome to Pyto.md */; };
 		C9EDF9AB21446FCA00382DCC /* ConsoleViewController.swift in Sources */ = {isa = PBXBuildFile; fileRef = C9EDF9AA21446FCA00382DCC /* ConsoleViewController.swift */; };
 		C9F04E832173C33400BDD03E /* Localizable.strings in Resources */ = {isa = PBXBuildFile; fileRef = C9F04E852173C33400BDD03E /* Localizable.strings */; };
 		C9F04E882173DD7300BDD03E /* Main.storyboard in Resources */ = {isa = PBXBuildFile; fileRef = C9F04E8A2173DD7300BDD03E /* Main.storyboard */; };
@@ -448,6 +449,7 @@
 		C9E509A121BC08F800261E3A /* docs */ = {isa = PBXFileReference; lastKnownFileType = folder; path = docs; sourceTree = SOURCE_ROOT; };
 		C9E7ABAA2152D0D30007BB87 /* libsqlite3.0.tbd */ = {isa = PBXFileReference; lastKnownFileType = "sourcecode.text-based-dylib-definition"; name = libsqlite3.0.tbd; path = usr/lib/libsqlite3.0.tbd; sourceTree = SDKROOT; };
 		C9EA55B2219F752D007546BC /* RelativePathForScript.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = RelativePathForScript.swift; sourceTree = "<group>"; };
+		C9EA5C7C21F23024000F7FA7 /* Welcome to Pyto.md */ = {isa = PBXFileReference; lastKnownFileType = net.daringfireball.markdown; path = "Welcome to Pyto.md"; sourceTree = "<group>"; };
 		C9EDF9A4214461D300382DCC /* libsqlite3.tbd */ = {isa = PBXFileReference; lastKnownFileType = "sourcecode.text-based-dylib-definition"; name = libsqlite3.tbd; path = usr/lib/libsqlite3.tbd; sourceTree = SDKROOT; };
 		C9EDF9A62144620A00382DCC /* libz.tbd */ = {isa = PBXFileReference; lastKnownFileType = "sourcecode.text-based-dylib-definition"; name = libz.tbd; path = usr/lib/libz.tbd; sourceTree = SDKROOT; };
 		C9EDF9AA21446FCA00382DCC /* ConsoleViewController.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ConsoleViewController.swift; sourceTree = "<group>"; };
@@ -600,6 +602,7 @@
 				C9E415302151531B00D64E32 /* REPL.py */,
 				C9B5D87521F214DC00E980BA /* body.html */,
 				C9F04E852173C33400BDD03E /* Localizable.strings */,
+				C9EA5C7C21F23024000F7FA7 /* Welcome to Pyto.md */,
 				C9E509A121BC08F800261E3A /* docs */,
 			);
 			name = Resources;
@@ -1015,6 +1018,7 @@
 				C9B5D84B21F119B100E980BA /* About.storyboard in Resources */,
 				C9E509A221BC08F900261E3A /* docs in Resources */,
 				C9C0E78B21F0B5770057C63E /* Theme Chooser.storyboard in Resources */,
+				C9EA5C7D21F23558000F7FA7 /* Welcome to Pyto.md in Resources */,
 				C98472AE21A05CB1008E16AC /* README.md in Resources */,
 				C9F04E882173DD7300BDD03E /* Main.storyboard in Resources */,
 				C9FCFD6D21442FD700A07974 /* Untitled.py in Resources */,

Pyto/View Controllers/DocumentBrowserViewController.swift

@@ -96,6 +96,10 @@ class DocumentBrowserViewController: UIViewController, UICollectionViewDataSourc
 
         if let iCloudURL = DocumentBrowserViewController.iCloudContainerURL, directory.pathComponents == DocumentBrowserViewController.localContainerURL.pathComponents {
 
+            if let welcome = Bundle.main.url(forResource: "Welcome to Pyto", withExtension: "md") {
+                files.append(welcome)
+            }
+
             if !FileManager.default.fileExists(atPath: iCloudURL.path) {
                 try? FileManager.default.createDirectory(at: iCloudURL, withIntermediateDirectories: true, attributes: nil)
             }

Pyto/View Controllers/PlainTextEditorViewController.swift

@@ -25,17 +25,23 @@ class PlainTextEditorViewController: UIViewController, UITextViewDelegate {
                 parent?.title = title
                 textView.text = (try? String(contentsOf: url)) ?? ""
 
+                textView.contentTextView.isEditable = !isBundled
+
                 (parent as? MarkdownSplitViewController)?.previewer.load(markdown: textView.text, baseURL: url.deletingLastPathComponent())
             }
         }
     }
 
+    /// Returns `true` if the file is in the app's bundle.
+    var isBundled: Bool {
+        return (url != nil && url!.path.hasPrefix(Bundle.main.bundlePath))
+    }
+
     /// Closes this View controller and saves.
     @objc func close() {
         dismiss(animated: true) {
-
             do {
-                if let url = self.url {
+                if let url = self.url, !self.isBundled {
                     try self.textView.text.write(to: url, atomically: true, encoding: .utf8)
                 }
                 DispatchQueue.main.async {

Pyto/Views/FileCollectionViewCell.swift

@@ -229,12 +229,14 @@ class FileCollectionViewCell: UICollectionViewCell, UIDocumentPickerDelegate, Sy
     }
 
     override func canPerformAction(_ action: Selector, withSender sender: Any?) -> Bool {
-        if isDirectory.boolValue {
+        if file?.path.hasPrefix(Bundle.main.bundlePath) == true {
+            return (action == #selector(open(_:)))
+        } else if isDirectory.boolValue || file?.pathExtension.lowercased() == "md" || file?.pathExtension.lowercased() == "markdown" {
             return (
                 action == #selector(remove(_:)) ||
-                    action == #selector(rename(_:)) ||
-                    action == #selector(copyFile(_:)) ||
-                    action == #selector(move(_:))
+                action == #selector(rename(_:)) ||
+                action == #selector(copyFile(_:)) ||
+                action == #selector(move(_:))
             )
         } else {
             return (
@@ -261,7 +263,17 @@ class FileCollectionViewCell: UICollectionViewCell, UIDocumentPickerDelegate, Sy
     func didChangeSelectedRange(_ syntaxTextView: SyntaxTextView, selectedRange: NSRange) {}
 
     func lexerForSource(_ source: String) -> Lexer {
-        return Python3Lexer()
+        if file?.pathExtension.lowercased() == "py" {
+            return Python3Lexer()
+        } else {
+            struct PlainTextLexer: SourceCodeRegexLexer {
+                func generators(source: String) -> [TokenGenerator] {
+                    return []
+                }
+            }
+
+            return PlainTextLexer()
+        }
     }
 
     // MARK: - Collection view data source

Pyto/Welcome to Pyto.md

@@ -0,0 +1,23 @@
+#  Welcome to Pyto
+
+Thank you for downloading Pyto. You can now write and run Python scripts.
+
+# Getting Started
+
+* Tap `⊞` to return to the file browser.
+
+* To create a new script, tap  `+` at top right of the file browser.
+
+* To run a script open it and tap `►`. The output will be shown and the keyboard will appear when input will be required.
+
+* To pass arguments, tap the `args` button
+
+* To change the app's theme, press the `Info` button at top left of the file browser, then tap `Theme` and choose the theme you want.
+
+# Installing third party modules
+
+Pyto has a minimal version of pip. 
+
+For installing a module, tap `pip` button on the file browser. Arguments will be asked. If you want to install a module, write `install <module_name>` and if you want to uninstall a module, then write `uninstall <module_name>`.
+
+Pyto cannot compile modules and cannot link shared libraries from outside the app bundle. So `pip` will fail for packages like `pandas`, `scipy` or `numpy`. `numpy` is already included. I'm trying to include `pandas`, but it's not easy.