Update Sample Data Import to use file browser

Also temporarily change type from 'tool' to 'generate' to allow testing
while Tools menu still has problems.

plug-ins/sample-data-import.ny

@@ -1,15 +1,16 @@
 $nyquist plug-in
 $version 4
-$type tool
+$type generate
 $name (_ "Sample Data Import")
 $manpage "Sample_Data_Import"
 $action (_ "Reading and rendering samples...")
 $author (_ "Steve Daulton")
 $copyright (_ "Released under terms of the GNU General Public License version 2")
 
-;; sample-data-import.ny by Steve Daulton November 2016.
-;; Released under terms of the GNU General Public License version 2:
-;; http://www.gnu.org/licenses/old-licenses/gpl-2.0.html
+$control filename (_ "Select file") file "" "*default*/sample-data.txt" "Text file|*.txt;*.TXT|All files|*.*;*" "open,exists"
+$control bad-data (_ "Invalid data handling") choice (("ThrowError" (_ "Throw Error"))
+                                                      ("ReadAsZero" (_ "Read as Zero"))) 0
+
 
 ;; Released under terms of the GNU General Public License version 2:
 ;; http://www.gnu.org/licenses/old-licenses/gpl-2.0.html
@@ -18,146 +19,23 @@ $copyright (_ "Released under terms of the GNU General Public License version 2"
 ;; https://wiki.audacityteam.org/wiki/Nyquist_Plug-ins_Reference
 
 
-;; Documentation.
-;;
-;; Introduction:
-;; This plug-in reads numeric values from the specified
-;; file and creates a PCM sample for each numeric value
-;; read. The values are read as 32-bit float numbers,
-;; where a range of +/- 1.0 represents 0 dB (full scale).
-;; The file MUST be plain ASCII text, and values should
-;; be separated by spaces, tabs or line-breaks.
-;; The file name must have a '.txt' file extension.
-;;
-;; *** ATTENTION ***
-;; The file to be imported must contain
-;; plain ASCII text only.
-;; Files other than plain ASCII text are NOT SUPPORTED.
-;; ***************
-;; 
-;; Depending on the computer file system, the file name
-;; may be case sensitive. The named file must be located
-;; in the specified directory (the "File location").
-;; The directory may be one of:
-;; 1) "Home Directory" (without quotes. This is the default).
-;;    The "Home Directory" is normally:
-;;    C:\Users\<username>  (Windows)
-;;    /Users/<username>    (Mac OS X)
-;;    /home/<username>     (Linux)
-;; 2) The fully qualified path, for example:
-;;    C:\Users\(User_Name)\Documents
-;; 3) Linux & Mac only:
-;;    The fully qualified path using "~/" (tilde slash)
-;;    as an abbreviation for the Home folder.
-;; If the "File location" is not defined (empty), the
-;; plug-in will look in the "home" folder for the named
-;; file.
-;; If the file cannot be found, the plug-in will abort
-;; and an error will be shown.
-;; 
-;; Number of channels:
-;; If a stereo track is selected, then the data is assumed
-;; to be stereo, otherwise the data will be treated as
-;; mono.
-;; Stereo data must be interleaved (alternate left/right
-;; sample values).
-;; 
-;; Data format:
-;; Sample data must be plain ASCII text only and should
-;; be numeric values only.
-;; 
-;; Values must be separated by one of:
-;; 1) One or more spaces.
-;; 2) One or more tabs.
-;; 3) One or more line breaks.
-;; 4) Any combination of the above.
-;; 
-;; Data comments:
-;; Comments may be included in the file by preceding
-;; the comment with a semicolon. All text between a
-;; semicolon and the end of the line is ignored.
-;;
-;; Invalid data handling:
-;; There are two options for handling invalid data:
-;; 1) Throw error (default):
-;;    Any text that cannot be read as a numeric value
-;;    will abort the effect and display an error message.
-;;    The error message will attempt to display the
-;;    invalid text.
-;; 2) Read as zero:
-;;    Any text that cannot be read as a numeric value
-;;    will produce a zero (silent) sample value.
-;; 
-;; Further information:
-;; https://manual.audacityteam.org/man/sample_data_import.html
-
-
-$control filename (_ "File name") string "" "sample-data.txt"
-$control path (_ "File location (path to file)") string "" "Home directory"
-$control bad-data (_ "Invalid data handling") choice (
-   ("ThrowError" (_ "Throw Error"))
-   ("ReadAsZero" (_ "Read as Zero"))
-) 0
-
-
-;; home directory
-(defun home ()
-  (if (windowsp)
-      (get-env "UserProfile") ;Windows
-      (get-env "HOME")));Mac / Linux
-
-;; Check if OS is Windows
-(defun windowsp ()
-  (char= #\\ *file-separator*))
-
 ;; Check file can be opened
-;; As Nyquist plug-ins do not (yet) have a file browser,
-;; we need to be quite rigorous with error checking here.
-(defun fileopensp (path fname)
-  (let ((path (string-trim " " path)))
-    (if (string-equal fname "")
-        (throw 'err (format nil (_ "Error~%No file name."))))
-    (if (string-not-equal fname ".txt" :start1 (- (length fname) 4))
-        (throw 'err (format nil (_ "Error~%The file must be a plain ASCII text file~%with '.txt' file extension."))))
-    ;; Handle special 'path' formats:
-    (cond
-      ; "~" without "/" is not recommended (or documented)
-      ; but more user friendly to allow it.
-      ((string= path "~")
-          (if (windowsp)
-	  ;i18n-hint: ~~ format directive must be preserved; displays as one ~
-              (format nil (_ "Error~%'~~/' is not valid on Windows"))
-              (setq path (home))))
-      ;; replace "~/" on Linux/Mac
-      ((and (>= (length path) 2) (string= path "~/" :end1 2))
-          (if (windowsp)
-	  ;i18n-hint: ~~ format directive must be preserved; displays as one ~
-              (format nil (_ "Error~%'~~/' is not valid on Windows"))
-              (setq path (strcat (home)(subseq path 1)))))
-      ((string-equal path (_ "Home directory"))
-          (setf path (home)))
-      ;; If empty, use 'Home'
-      ((string-equal path "")
-          (setf path (home))))
-    ;; Now check that the file can be opened:
-    (cond
-      ((not (setdir path))
-          (throw 'err (format nil (_ "Error~%~
-                          Directory '~a' could not be opened.") path)))
-      ((not (setf fstream (open fname)))
-          (throw 'err (format nil (_ "Error~%~
-                          '~a~a~a' could not be opened.~%~
-                          Check that file exists.")
-                          path *file-separator* fname)))
-      ; File opened OK, so check for normal ASCII, then close it and return 'true'
-      (t  (do ((j 0 (1+ j))(b (read-byte fstream)(read-byte fstream)))
-              ((or (> j 100000)(not b)))
-            (when (> b 127)
-              (throw 'err (format nil (_ "Error:~%~
-                The file must contain only plain ASCII text.~%~
-                (Invalid byte '~a' at byte number: ~a)") b (1+ j) ))))
-          (close fstream)
-          t))))
+(defun fileopensp (fname)
+  (cond
+    ((not (setf fstream (open fname)))
+        (throw 'err (format nil (_ "Error~%~
+                        '~a' could not be opened.~%~
+                        Check that file exists.")
+                        fname)))
+    ; File opened OK, so check for normal ASCII, then close it and return 'true'
+    (t  (do ((j 0 (1+ j))(b (read-byte fstream)(read-byte fstream)))
+            ((or (> j 100000)(not b)))
+          (when (> b 127)
+            (throw 'err (format nil (_ "Error:~%~
+              The file must contain only plain ASCII text.~%~
+              (Invalid byte '~a' at byte number: ~a)") b (1+ j) ))))
+        (close fstream)
+        t)))
 
 ;; ':new' creates a new class 'streamreader'
 ;; 'filestream' and 'chanel' are its instance variables.
@@ -205,7 +83,7 @@ $control bad-data (_ "Invalid data handling") choice (
 
 (defun sound-from-file (filename)
   ;; Set path. fileopenp should return 'true'
-  (if (not (fileopensp path filename))
+  (if (not (fileopensp filename))
       (throw 'err (format nil (_ "Error.~%Unable to open file"))))
   ; Note: we can't use (arrayp *track*) because
   ; *track* is nil in generate type plug-ins.