1# Copyright 2014 Dirk Pranke. All rights reserved.
2#
3# Licensed under the Apache License, Version 2.0 (the "License");
4# you may not use this file except in compliance with the License.
5# You may obtain a copy of the License at
6#
7#    http://www.apache.org/licenses/LICENSE-2.0
8#
9# Unless required by applicable law or agreed to in writing, software
10# distributed under the License is distributed on an "AS IS" BASIS,
11# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12# See the License for the specific language governing permissions and
13# limitations under the License.
14
15
16class Printer(object):
17
18    def __init__(self, print_, should_overwrite, cols):
19        self.print_ = print_
20        self.should_overwrite = should_overwrite
21        self.cols = cols
22        self.last_line = ''
23
24    def flush(self):
25        if self.last_line:
26            self.print_('')
27            self.last_line = ''
28
29    def update(self, msg, elide=True):
30        msg_len = len(msg)
31        if elide and self.cols and msg_len > self.cols - 5:
32            new_len = int((self.cols - 5) / 2)
33            msg = msg[:new_len] + '...' + msg[-new_len:]
34        if self.should_overwrite and self.last_line:
35            self.print_('\r' + ' ' * len(self.last_line) + '\r', end='')
36        elif self.last_line:
37            self.print_('')
38        self.print_(msg, end='')
39        last_nl = msg.rfind('\n')
40        self.last_line = msg[last_nl + 1:]
41