Add proper support for double width characters to legacy mode and few related formatting functions

deluge/ui/console/colors.py

@@ -33,6 +33,8 @@
 #
 #
 
+from deluge.ui.console.modes import format_utils
+
 try:
     import curses
 except ImportError:
@@ -150,6 +152,24 @@ def get_line_length(line, encoding="UTF-8"):
     line = replace_tabs(line)
     return len(line)
 
+def get_line_width(line, encoding="UTF-8"):
+    """
+    Get width of string considering double width characters
+
+    """
+    if line.count("{!") != line.count("!}"):
+        raise BadColorString("Number of {! is not equal to number of !}")
+
+    if isinstance(line, unicode):
+        line = line.encode(encoding, "replace")
+
+    # Remove all the color tags
+    line = strip_colors(line)
+
+    # Replace tabs with the appropriate amount of spaces
+    line = replace_tabs(line)
+    return format_utils.strwidth(line)
+
 def parse_color_string(s, encoding="UTF-8"):
     """
     Parses a string and returns a list of 2-tuples (color, string).

deluge/ui/console/modes/format_utils.py

@@ -201,3 +201,33 @@ def wrap_string(string,width,min_lines=0,strip_colors=True):
             ret.append(" ")
 
     return ret
+
+from unicodedata import east_asian_width
+
+def strwidth(string):
+    """
+    Measure width of a string considering asian double width characters
+    """
+    if not isinstance(string, unicode):
+        string = unicode(string, 'utf-8')
+    eaw = east_asian_width
+    length = sum( [1 + (eaw(c) in ['W','F']) for c in string] )
+    #Using list comprehenstion for improved performance
+    #The code above is equal to:
+    #length = 0
+    #for char in string:
+        #length += 1
+        #if east_asian_width(char) in ['W','F']:
+            #length += 1
+    return length
+
+def pad_string(string, length, character=" ", side="right"):
+    """
+    Pad string with specified character to desired length, considering double width characters.
+    """
+    w = strwidth(string)
+    diff = length - w
+    if   side == "left":
+        return "%s%s" % (character * diff, string)
+    elif side == "right":
+        return "%s%s" % (string, character * diff)

deluge/ui/console/modes/legacy.py

@@ -47,6 +47,7 @@ from deluge.ui.client import client
 import deluge.component as component
 
 from deluge.ui.console.modes import format_utils
+strwidth = format_utils.strwidth
 
 import logging,os
 log = logging.getLogger(__name__)
@@ -353,7 +354,7 @@ class Legacy(BaseMode):
         for line in text.splitlines():
             # We need to check for line lengths here and split as necessary
             try:
-                line_length = colors.get_line_length(line)
+                line_length = colors.get_line_width(line)
             except colors.BadColorString:
                 log.error("Passed a bad colored line: %s", line)
                 continue
@@ -364,11 +365,11 @@ class Legacy(BaseMode):
                 s_len = 0
                 # We need to split this over multiple lines
                 for chunk in get_line_chunks(line):
-                    if (len(chunk[1]) + s_len) < (self.cols - 1):
+                    if (strwidth(chunk[1]) + s_len) < (self.cols - 1):
                         # This chunk plus the current string in 's' isn't over
                         # the maximum width, so just append the color tag and text
                         s += chunk[0] + chunk[1]
-                        s_len += len(chunk[1])
+                        s_len += strwidth(chunk[1])
                     else:
                         # The chunk plus the current string in 's' is too long.
                         # We need to take as much of the chunk and put it into 's'
@@ -379,7 +380,7 @@ class Legacy(BaseMode):
                         self.lines.append(s)
                         # Start a new 's' with the remainder chunk
                         s = chunk[0] + chunk[1][remain:]
-                        s_len = len(chunk[1][remain:])
+                        s_len = strwidth(chunk[1][remain:])
                 # Append the final string which may or may not be the full width
                 if s:
                     self.lines.append(s)
@@ -411,13 +412,13 @@ class Legacy(BaseMode):
         for index, (color, s) in enumerate(parsed):
             if index + 1 == len(parsed):
                 # This is the last string so lets append some " " to it
-                s += " " * (self.cols - (col + len(s)) - 1)
+                s += " " * (self.cols - (col + strwidth(s)) - 1)
             try:
                 self.stdscr.addstr(row, col, s, color)
             except curses.error:
                 pass
 
-            col += len(s)
+            col += strwidth(s)
 
 
     def do_command(self, cmd):