New target description + moving target stuff under "framework"

Changing the way target descriptions work from a static mapping to
something that is dynamically generated and is extensible via plugins.
Also moving core target implementation stuff under "framework".

wa/utils/formatter.py

@@ -0,0 +1,148 @@
+#    Copyright 2013-2015 ARM Limited
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+
+from wa.utils.terminalsize import get_terminal_size
+
+
+INDENTATION_FROM_TITLE = 4
+
+
+class TextFormatter(object):
+
+    """
+    This is a base class for text formatting. It mainly ask to implement two
+    methods which are add_item and format_data. The formar will add new text to
+    the formatter, whereas the latter will return a formatted text. The name
+    attribute represents the name of the foramtter.
+    """
+
+    name = None
+    data = None
+
+    def __init__(self):
+        pass
+
+    def add_item(self, new_data, item_title):
+        """
+        Add new item to the text formatter.
+
+        :param new_data: The data to be added
+        :param item_title: A title for the added data
+        """
+        raise NotImplementedError()
+
+    def format_data(self):
+        """
+        It returns a formatted text
+        """
+        raise NotImplementedError()
+
+
+class DescriptionListFormatter(TextFormatter):
+
+    name = 'description_list_formatter'
+    data = None
+
+    def get_text_width(self):
+        if not self._text_width:
+            self._text_width, _ = get_terminal_size()  # pylint: disable=unpacking-non-sequence
+        return self._text_width
+
+    def set_text_width(self, value):
+        self._text_width = value
+
+    text_width = property(get_text_width, set_text_width)
+
+    def __init__(self, title=None, width=None):
+        super(DescriptionListFormatter, self).__init__()
+        self.data_title = title
+        self._text_width = width
+        self.longest_word_length = 0
+        self.data = []
+
+    def add_item(self, new_data, item_title):
+        if len(item_title) > self.longest_word_length:
+            self.longest_word_length = len(item_title)
+        self.data[len(self.data):] = [(item_title, self._remove_newlines(new_data))]
+
+    def format_data(self):
+        parag_indentation = self.longest_word_length + INDENTATION_FROM_TITLE
+        string_formatter = '{}:<{}{} {}'.format('{', parag_indentation, '}', '{}')
+
+        formatted_data = ''
+        if self.data_title:
+            formatted_data += self.data_title
+
+        line_width = self.text_width - parag_indentation
+        for title, paragraph in self.data:
+            formatted_data += '\n'
+            title_len = self.longest_word_length - len(title)
+            title += ':'
+            if title_len > 0:
+                title = (' ' * title_len) + title
+
+            parag_lines = self._break_lines(paragraph, line_width).splitlines()
+            if parag_lines:
+                formatted_data += string_formatter.format(title, parag_lines[0])
+                for line in parag_lines[1:]:
+                    formatted_data += '\n' + string_formatter.format('', line)
+            else:
+                formatted_data += title[:-1]
+
+        self.text_width = None
+        return formatted_data
+
+    # Return text's paragraphs sperated in a list, such that each index in the
+    # list is a single text paragraph with no new lines
+    def _remove_newlines(self, new_data):  # pylint: disable=R0201
+        parag_list = ['']
+        parag_num = 0
+        prv_parag = None
+        # For each paragraph sperated by a new line
+        for paragraph in new_data.splitlines():
+            if paragraph:
+                parag_list[parag_num] += ' ' + paragraph
+            # if the previous line is NOT empty, then add new empty index for
+            # the next paragraph
+            elif prv_parag:
+                parag_num = 1
+                parag_list.append('')
+            prv_parag = paragraph
+
+        # sometimes, we end up with an empty string as the last item so we reomve it
+        if not parag_list[-1]:
+            return parag_list[:-1]
+        return parag_list
+
+    def _break_lines(self, parag_list, line_width):  # pylint: disable=R0201
+        formatted_paragraphs = []
+        for para in parag_list:
+            words = para.split()
+            if words:
+                formatted_text = words.pop(0)
+                current_width = len(formatted_text)
+                # for each word in the paragraph, line width is an accumlation of
+                # word length + 1 (1 is for the space after each word).
+                for word in words:
+                    word = word.strip()
+                    if current_width + len(word) + 1 >= line_width:
+                        formatted_text += '\n' + word
+                        current_width = len(word)
+                    else:
+                        formatted_text += ' ' + word
+                        current_width += len(word) + 1
+                formatted_paragraphs.append(formatted_text)
+        return '\n\n'.join(formatted_paragraphs)