Allow multiline output

3 files changed, 139 insertions, 33 deletions

diff --git a/example2.py b/example2.py
new file mode 100644
index 0000000..4600bf2
--- /dev/null
+++ b/example2.py
@@ -0,0 +1,59 @@
+# Copyright 2015  Lars Wirzenius
+# 
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+# 
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+# 
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+
+'''An example program for ttystatus: compute checksums.'''
+
+
+import hashlib
+import os
+import sys
+
+import ttystatus
+
+
+num_bytes = 1024**2
+
+
+def main():
+    ts = ttystatus.TerminalStatus(period=0.1)
+
+    ts.format(
+        'Elapsed time: %ElapsedTime()\n'
+        'Current file: %Pathname(filename)\n'
+        'File count: %Counter(filename)\n'
+        'Combined size: %ByteSize(bytes-read)\n'
+        'Checksum speed: %ByteSpeed(bytes-read)'
+    )
+    ts['bytes-read'] = 0
+
+    for dirname, subdirs, basenames in os.walk(sys.argv[1]):
+        for basename in basenames:
+            filename = os.path.join(dirname, basename)
+            if os.path.isfile(filename):
+                ts['filename'] = filename
+                checksum = hashlib.sha512()
+                with open(filename, 'rb') as f:
+                    data = f.read(num_bytes)
+                    checksum.update(data)
+                    ts['bytes-read'] += len(data)
+                if checksum.hexdigest().startswith('0'):
+                    ts.notify('%s %s' % (checksum.hexdigest(), filename))
+        
+    ts.finish()
+
+
+if __name__ == '__main__':
+    main()
diff --git a/ttystatus/messager.py b/ttystatus/messager.py
index cfab8ad..71013e3 100644
--- a/ttystatus/messager.py
+++ b/ttystatus/messager.py
@@ -14,6 +14,7 @@
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 
+import curses
 import fcntl
 import struct
 import termios
@@ -35,14 +36,16 @@ class Messager(object):
             except IOError:
                 self.output = None
         self._period = 1.0 if period is None else period
-        self._last_msg = ''    # What did we write last?
         self._last_time = 0    # When did we write last?
         self._cached_msg = ''  # Last message from user, to write() method.
+        self._first_output = True  # is our next output the first one?
         self._fake_width = fake_width
         self.set_width(self._get_terminal_width())  # Width of terminal
 
     def _open_tty(self):  # pragma: no cover
-        return open('/dev/tty', 'w')
+        f = open('/dev/tty', 'wb')
+        curses.setupterm(None, f.fileno())
+        return f
 
     def set_width(self, actual_width):
         self.width = actual_width - 1
@@ -78,13 +81,7 @@ class Messager(object):
         return width
 
     def update_width(self):  # pragma: no cover
-        new_width = self._get_terminal_width()
-        if new_width != self.width:
-            # Clear the terminal from old stuff, using the old width.
-            self.clear()
-            # Get new width.
-            self.set_width(new_width)
-            self._overwrite(self._last_msg)
+        self.set_width(self._get_terminal_width())
 
     def _raw_write(self, string):
         '''Write raw data if output is terminal.'''
@@ -96,13 +93,6 @@ class Messager(object):
             except IOError:  # pragma: no cover
                 self._enabled = False
 
-    def _overwrite(self, string):
-        '''Overwrite current message on terminal.'''
-        if self._last_msg:
-            self._raw_write('\r' + (' ' * len(self._last_msg)) + '\r')
-        self._raw_write(string)
-        self._last_msg = string
-
     def time_to_write(self):
         '''Is it time to write now?'''
         return self._now() - self._last_time >= self._period
@@ -110,14 +100,59 @@ class Messager(object):
     def write(self, string):
         '''Write raw data, always.'''
         self.update_width()
-        string = string[:self.width]
-        self._overwrite(string)
-        self._last_time = self._now()
+        rows = string.split('\n')
+
+        raw_parts = []
+
+        if self._first_output:
+            raw_parts.append('\n' * (len(rows) - 1))
+            self._first_output = False
+
+        if rows:
+            raw_parts.extend([
+                curses.tparm(curses.tigetstr('cuu'), len(rows) - 1),  # go up
+                curses.tigetstr('cr'),  # beginning of line
+                curses.tigetstr('el'),  # erase to end of line
+                rows[0][:self.width],
+            ])
+            for row in rows[1:]:
+                raw_parts.extend([
+                    curses.tparm(curses.tigetstr('cud'), 1),  # down one line
+                    curses.tigetstr('cr'),  # beginning of line
+                    curses.tigetstr('el'),  # erase to end of line
+                    row[:self.width],
+                ])
+
+        raw = ''.join(raw_parts)
+        self._raw_write(raw)
         self._cached_msg = string
+        self._last_time = self._now()
 
     def clear(self):
         '''Remove current message from terminal.'''
-        self._overwrite('')
+
+        rows = self._cached_msg.split('\n')
+
+        raw_parts = []
+
+        if rows:
+            raw_parts.extend([
+                curses.tparm(curses.tigetstr('cuu'), len(rows) - 1),  # go up
+                curses.tigetstr('cr'),  # beginning of line
+                curses.tigetstr('el'),  # erase to end of line
+            ])
+            for row in rows[1:]:
+                raw_parts.extend([
+                    curses.tparm(curses.tigetstr('cud'), 1),  # down one line
+                    curses.tigetstr('cr'),  # beginning of line
+                    curses.tigetstr('el'),  # erase to end of line
+                ])
+            raw_parts.extend([
+                curses.tparm(curses.tigetstr('cuu'), len(rows) - 1),  # go up
+            ])
+
+        raw = ''.join(raw_parts)
+        self._raw_write(raw)
 
     def notify(self, string, f, force=False):
         '''Show a notification message string to the user.
@@ -133,7 +168,6 @@ class Messager(object):
         '''
 
         if self._enabled or force:
-            old = self._last_msg
             self.clear()
             try:
                 f.write('%s\n' % string)
@@ -141,12 +175,13 @@ class Messager(object):
             except IOError:
                 # We ignore these. No point in crashing if terminal is bad.
                 pass
-            self._overwrite(old)
+            self._first_output = True
+            self.write(self._cached_msg)
 
     def finish(self):
         '''Finalize output.'''
-        if self._last_msg or self._cached_msg:
-            self._overwrite(self._cached_msg)
+        if self._cached_msg:
+            self.write(self._cached_msg)
             self._raw_write('\n')
 
     def disable(self):
diff --git a/ttystatus/status.py b/ttystatus/status.py
index 11676cb..61adcbe 100644
--- a/ttystatus/status.py
+++ b/ttystatus/status.py
@@ -38,7 +38,11 @@ class TerminalStatus(object):
 
     def add(self, widget):
         '''Add a new widget to the status display.'''
-        self._widgets.append(widget)
+        self._widget_rows[-1].append(widget)
+
+    def start_new_line(self):
+        '''Start a new line of widgets.'''
+        self._widget_rows.append([])
 
     def format(self, format_string):
         '''Add new widgets based on format string.
@@ -49,12 +53,16 @@ class TerminalStatus(object):
         ``format("hello, %String(name)")``.
 
         '''
-        for widget in ttystatus.parse(format_string):
-            self.add(widget)
+
+        for i, line in enumerate(format_string.split('\n')):
+            if i > 0:
+                self.start_new_line()
+            for widget in ttystatus.parse(line):
+                self.add(widget)
 
     def clear(self):
         '''Remove all widgets.'''
-        self._widgets = []
+        self._widget_rows = [[]]
         self._values = dict()
         self._m.clear()
 
@@ -69,8 +77,9 @@ class TerminalStatus(object):
     def __setitem__(self, key, value):
         '''Set value for key.'''
         self._values[key] = value
-        for w in self._widgets:
-            w.update(self)
+        for row in self._widget_rows:
+            for w in row:
+                w.update(self)
         if self._m.time_to_write():
             self._write()
 
@@ -86,16 +95,19 @@ class TerminalStatus(object):
     def _render(self):
         '''Render current state of all widgets.'''
 
+        return '\n'.join(self._render_row(row) for row in self._widget_rows)
+
+    def _render_row(self, widget_row):
         remaining = self._m.width
 
-        texts = [None] * len(self._widgets)
+        texts = [None] * len(widget_row)
 
-        for i, w in enumerate(self._widgets):
+        for i, w in enumerate(widget_row):
             if w.static_width:
                 texts[i] = w.render(0)
                 remaining -= len(texts[i])
 
-        for i, w in enumerate(self._widgets):
+        for i, w in enumerate(widget_row):
             if not w.static_width:
                 texts[i] = w.render(remaining)
                 remaining -= len(texts[i])