Added saving code blocks of every programming language (#1117)

app/MindWork AI Studio/Tools/MessageFile.cs

@@ -1,14 +1,65 @@
+using System.Text;
+
+using AIStudio.Tools.Rust;
+
 namespace AIStudio.Tools;
 
 /// <summary>
-/// A file found in a message, ready to be written: a table the model wrote, or a code block the
-/// model marked as a format we write.
+/// A file found in a message, ready to be written: a table the model wrote, or one of its code blocks.
 /// </summary>
+/// <remarks>
+/// The export menu and the writer ask the file how it is named and written, never its format
+/// directly: code in Python and code in Rust share the format SOURCE_CODE, and only the language
+/// of the file tells them apart.
+/// </remarks>
 /// <param name="Ordinal">Which table or which code block of the message this is, counting from one
 /// within its kind; the format tells the two kinds apart, see FileExportFormatExtensions.IsTabular.
 /// This is what tells two files of one kind apart even when they carry the same heading.</param>
+/// <param name="Position">Where the table or code block starts in the Markdown text the file was
+/// read from, as the index of its first character. A block the chat renders finds its file by it:
+/// the chat renders an answer in parts, around its formulas, and each part knows where it starts.</param>
 /// <param name="Caption">What the file is about: the heading above it, or else the first column
 /// heading of a table. Empty for a code block without a heading above it.</param>
 /// <param name="Format">The format this content is written as.</param>
+/// <param name="Language">The language of the code, when the format is SOURCE_CODE; NONE for
+/// every other file.</param>
 /// <param name="Content">The finished file content.</param>
-public sealed record MessageFile(int Ordinal, string Caption, FileExportFormat Format, string Content);
+public sealed record MessageFile(int Ordinal, int Position, string Caption, FileExportFormat Format, SourceCodeLanguage Language, string Content)
+{
+    private bool IsSourceCode => this.Format is FileExportFormat.SOURCE_CODE;
+
+    /// <summary>
+    /// Returns the name of the file's type as shown to the user, for example "Webpage (.html)" or
+    /// "Python (.py)".
+    /// </summary>
+    public string ToName() => this.IsSourceCode ? this.Language.ToName() : this.Format.ToName();
+
+    /// <summary>
+    /// Returns the icon of the file's type.
+    /// </summary>
+    public string ToIcon() => this.Format.ToIcon();
+
+    /// <summary>
+    /// Returns what tells a file of this type apart: its extension, for example ".html", or the
+    /// fixed name a tool looks for, such as Dockerfile.
+    /// </summary>
+    public string ToFileExtensionOrName() => this.IsSourceCode ? this.Language.ToFileExtensionOrName() : this.Format.ToFileExtension();
+
+    /// <summary>
+    /// Returns the filter which the save dialog offers for the file.
+    /// </summary>
+    /// <returns>The filter, or null when AI Studio cannot write the file itself.</returns>
+    public FileTypeFilter? ToFileTypeFilter() => this.IsSourceCode ? this.Language.ToFileTypeFilter() : this.Format.ToFileTypeFilter();
+
+    /// <summary>
+    /// Returns the file name the save dialog starts with.
+    /// </summary>
+    /// <param name="name">What the file is about. Null or blank falls back to a generic name.</param>
+    /// <returns>The suggested file name.</returns>
+    public string ToSuggestedFileName(string? name = null) => this.IsSourceCode ? this.Language.ToSuggestedFileName(name) : this.Format.ToSuggestedFileName(name);
+
+    /// <summary>
+    /// Returns the encoding the file gets written with.
+    /// </summary>
+    public Encoding ToFileEncoding() => this.IsSourceCode ? this.Language.ToFileEncoding() : this.Format.ToFileEncoding();
+}