Merge branch 'feature/unique-prefix-tab-names' into 'master'

Unique prefix tab names

Closes #3525

See merge request poezio/poezio!94

12 files changed, 214 insertions, 3 deletions

diff --git a/data/default_config.cfg b/data/default_config.cfg
index 908a3d70..aef4d62a 100644
--- a/data/default_config.cfg
+++ b/data/default_config.cfg
@@ -548,6 +548,13 @@ use_bookmarks_method =
 # “true” should be the most comfortable value
 #lazy_resize = true
 
+# If set to true and if show_tab_names is set, the info bar will only show
+# the unique prefix of each tab name instead of the full name. This saves a
+# lot of space if many tabs exist or are active.
+# Best used with the `/wup` command or the `_go_to_room_name` action to select
+# a tab based on the prefix.
+#unique_prefix_tab_names = false
+
 [bindings]
 # Bindings are keyboard shortcut aliases. You can use them
 # to define your own keys and bind them with some functions
diff --git a/doc/source/commands.rst b/doc/source/commands.rst
index dab2eceb..5ea69abd 100644
--- a/doc/source/commands.rst
+++ b/doc/source/commands.rst
@@ -93,6 +93,15 @@ These commands work in *any* tab.
         Go to the matching tab.  If the argument is a number, it goes to the tab with that number.
         Otherwise, it goes to the next tab whose name contains the given string.
 
+    /wup
+
+        **Usage:** ``/wup <prefix>``
+
+        Go to the tab whose name starts with `prefix`. If multiple tabs start
+        with that prefix, no action is taken.
+
+        (Mnemonic: Window by Unique Prefix)
+
     /status
         **Usage:** ``/status <availability> [status message]``
 
diff --git a/doc/source/configuration.rst b/doc/source/configuration.rst
index 9619022a..aceb6fb4 100644
--- a/doc/source/configuration.rst
+++ b/doc/source/configuration.rst
@@ -793,6 +793,17 @@ or the way messages are displayed.
 
         If you want to show the tab name in the bottom Tab bar, set this to ``true``.
 
+    unique_prefix_tab_names
+
+        **Default value:** ``false``
+
+        If this and :term:`show_tab_names` is set to true, only the shortest
+        unique prefix of each tab name is shown instead of the full name. This
+        can declutter the interface in an instance with many tabs shown in the
+        interface, while not having to use numbers (which may change completely due to reordering).
+
+        Takes precedence over `use_tab_nicks`.
+
     show_tab_numbers
 
         **Default value:** ``true``
diff --git a/doc/source/keys.rst b/doc/source/keys.rst
index dc5fa35b..03ab2071 100644
--- a/doc/source/keys.rst
+++ b/doc/source/keys.rst
@@ -374,6 +374,15 @@ Actions list
 
     Similar to F4.
 
+**_go_to_room_name**: Jump to a tab by unique prefix.
+
+    Similar to :term:`/wup` and the default *Alt-j*. This action will take
+    input as long as there is at least one tab name starting with the input
+    given so far. If there is exactly one tab matching, the action completes
+    and the current tab is switched over to the tab matching the input. If
+    no tab matches, the action completes without any change. This means that
+    you can typically abort the action with Escape.
+
 Status actions
 ~~~~~~~~~~~~~~
 
diff --git a/poezio/common.py b/poezio/common.py
index ba179310..7cddc306 100644
--- a/poezio/common.py
+++ b/poezio/common.py
@@ -17,6 +17,7 @@ import subprocess
 import time
 import string
 import logging
+import itertools
 
 from slixmpp import JID, InvalidJID, Message
 from poezio.poezio_shlex import shlex
@@ -468,3 +469,22 @@ def safeJID(*args, **kwargs) -> JID:
             exc_info=True,
         )
         return JID('')
+
+
+def unique_prefix_of(a: str, b: str) -> str:
+    """
+    Return the unique prefix of `a` with `b`.
+
+    Corner cases:
+
+    * If `a` and `b` share no prefix, the first letter of `a` is returned.
+    * If `a` and `b` are equal, `a` is returned.
+    * If `a` is a prefix of `b`, `a` is returned.
+    * If `b` is a prefix of `a`, `b` plus the first letter of `a` after the
+      common prefix is returned.
+    """
+    for i, (ca, cb) in enumerate(itertools.zip_longest(a, b)):
+        if ca != cb:
+            return a[:i+1]
+    # both are equal, return a
+    return a
diff --git a/poezio/config.py b/poezio/config.py
index 8da71071..09d465cd 100644
--- a/poezio/config.py
+++ b/poezio/config.py
@@ -136,6 +136,7 @@ DEFAULT_CONFIG = {
         'theme': 'default',
         'themes_dir': '',
         'tmp_image_dir': '',
+        'unique_prefix_tab_names': False,
         'use_bookmarks_method': '',
         'use_log': True,
         'use_remote_bookmarks': True,
diff --git a/poezio/core/commands.py b/poezio/core/commands.py
index 6bf1d338..46dab5cc 100644
--- a/poezio/core/commands.py
+++ b/poezio/core/commands.py
@@ -219,6 +219,20 @@ class CommandCore:
                 return
             self.core.tabs.set_current_tab(match)
 
+    @command_args_parser.quoted(1)
+    def wup(self, args):
+        """
+        /wup <prefix of name>
+        """
+        if args is None:
+            return self.help('wup')
+
+        prefix = args[0]
+        _, match = self.core.tabs.find_by_unique_prefix(prefix)
+        if match is None:
+            return
+        self.core.tabs.set_current_tab(match)
+
     @command_args_parser.quoted(2)
     def move_tab(self, args):
         """
diff --git a/poezio/core/core.py b/poezio/core/core.py
index 06d56062..8ac88dd4 100644
--- a/poezio/core/core.py
+++ b/poezio/core/core.py
@@ -209,6 +209,7 @@ class Core:
             '_show_plugins': self.command.plugins,
             '_show_xmltab': self.command.xml_tab,
             '_toggle_pane': self.toggle_left_pane,
+            "_go_to_room_name": self.go_to_room_name,
             ###### status actions ######
             '_available': lambda: self.command.status('available'),
             '_away': lambda: self.command.status('away'),
@@ -1108,6 +1109,34 @@ class Core:
 
         keyboard.continuation_keys_callback = read_next_digit
 
+    def go_to_room_name(self) -> None:
+        room_name_jump = []
+
+        def read_next_letter(s) -> None:
+            nonlocal room_name_jump
+            room_name_jump.append(s)
+            any_matched, unique_tab = self.tabs.find_by_unique_prefix(
+                "".join(room_name_jump)
+            )
+
+            if not any_matched:
+                return
+
+            if unique_tab is not None:
+                self.tabs.set_current_tab(unique_tab)
+                # NOTE: returning here means that as soon as the tab is
+                # matched, normal input resumes. If we do *not* return here,
+                # any further characters matching the prefix of the tab will
+                # be swallowed (and a lot of tab switching will happen...),
+                # until a non-matching character or escape or something is
+                # pressed.
+                # This behaviour *may* be desirable.
+                return
+
+            keyboard.continuation_keys_callback = read_next_letter
+
+        keyboard.continuation_keys_callback = read_next_letter
+
     def go_to_roster(self) -> None:
         "Select the roster as the current tab"
         self.tabs.set_current_tab(self.tabs.first())
@@ -1709,6 +1738,12 @@ class Core:
             usage='<number or name>',
             shortdesc='Go to the specified room',
             completion=self.completion.win)
+        self.register_command(
+            'wup',
+            self.command.wup,
+            usage='<prefix>',
+            shortdesc='Go to the tab whose name uniquely starts with prefix',
+            completion=self.completion.win)
         self.commands['w'] = self.commands['win']
         self.register_command(
             'move_tab',
diff --git a/poezio/core/tabs.py b/poezio/core/tabs.py
index abea7313..d5909d39 100644
--- a/poezio/core/tabs.py
+++ b/poezio/core/tabs.py
@@ -24,11 +24,12 @@ have become [0|1|2|3], with the tab "4" renumbered to "3" if gap tabs are
 disabled.
 """
 
-from typing import List, Dict, Type, Optional, Union
+from typing import List, Dict, Type, Optional, Union, Tuple
 from collections import defaultdict
 from slixmpp import JID
 from poezio import tabs
 from poezio.events import EventHandler
+from poezio.config import config
 
 
 class Tabs:
@@ -139,6 +140,37 @@ class Tabs:
                     return self._tabs[i]
         return None
 
+    def find_by_unique_prefix(self, prefix: str) -> Tuple[bool, Optional[tabs.Tab]]:
+        """
+        Get a tab by its unique name prefix, ignoring case.
+
+        :return: A tuple indicating the presence of any match, as well as the
+            uniquely matched tab (if any).
+
+        The first element, a boolean, in the returned tuple indicates whether
+        at least one tab matched.
+
+        The second element (a Tab) in the returned tuple is the uniquely
+        matched tab, if any. If multiple or no tabs match the prefix, the
+        second element in the tuple is :data:`None`.
+        """
+
+        # TODO: should this maybe use something smarter than .lower()?
+        # something something stringprep?
+        prefix = prefix.lower()
+        candidate = None
+        any_matched = False
+        for tab in self._tabs:
+            if not tab.name.lower().startswith(prefix):
+                continue
+            any_matched = True
+            if candidate is not None:
+                # multiple tabs match -> return None
+                return True, None
+            candidate = tab
+
+        return any_matched, candidate
+
     def by_name_and_class(self, name: str,
                           cls: Type[tabs.Tab]) -> Optional[tabs.Tab]:
         """Get a tab with its name and class"""
diff --git a/poezio/windows/info_bar.py b/poezio/windows/info_bar.py
index ac900103..e94e1810 100644
--- a/poezio/windows/info_bar.py
+++ b/poezio/windows/info_bar.py
@@ -6,6 +6,7 @@ The GlobalInfoBar can be either horizontal or vertical
 (VerticalGlobalInfoBar).
 """
 import logging
+import itertools
 log = logging.getLogger(__name__)
 
 import curses
@@ -13,6 +14,7 @@ import curses
 from poezio.config import config
 from poezio.windows.base_wins import Win
 from poezio.theming import get_theme, to_curses_attr
+from poezio.common import unique_prefix_of
 
 
 class GlobalInfoBar(Win):
@@ -33,6 +35,34 @@ class GlobalInfoBar(Win):
         show_nums = config.get('show_tab_numbers')
         use_nicks = config.get('use_tab_nicks')
         show_inactive = config.get('show_inactive_tabs')
+        unique_prefix_tab_names = config.get('unique_prefix_tab_names')
+
+        if unique_prefix_tab_names:
+            unique_prefixes = [None] * len(self.core.tabs)
+            sorted_tab_indices = sorted(
+                (str(tab.name), i)
+                for i, tab in enumerate(self.core.tabs)
+            )
+            prev_name = ""
+            for (name, i), next_item in itertools.zip_longest(
+                    sorted_tab_indices, sorted_tab_indices[1:]):
+                # TODO: should this maybe use something smarter than .lower()?
+                # something something stringprep?
+                name = name.lower()
+                prefix_prev = unique_prefix_of(name, prev_name)
+                if next_item is not None:
+                    prefix_next = unique_prefix_of(name, next_item[0].lower())
+                else:
+                    prefix_next = name[0]
+
+                # to be unique, we have to use the longest prefix
+                if len(prefix_next) > len(prefix_prev):
+                    prefix = prefix_next
+                else:
+                    prefix = prefix_prev
+
+                unique_prefixes[i] = prefix
+                prev_name = name
 
         for nb, tab in enumerate(self.core.tabs):
             if not tab:
@@ -46,7 +76,9 @@ class GlobalInfoBar(Win):
                     if show_names:
                         self.addstr(' ', to_curses_attr(color))
                 if show_names:
-                    if use_nicks:
+                    if unique_prefix_tab_names:
+                        self.addstr(unique_prefixes[nb], to_curses_attr(color))
+                    elif use_nicks:
                         self.addstr("%s" % str(tab.get_nick()),
                                     to_curses_attr(color))
                     else:
diff --git a/test/test_common.py b/test/test_common.py
index d7bc2b8b..b6560fc9 100644
--- a/test/test_common.py
+++ b/test/test_common.py
@@ -11,7 +11,7 @@ from poezio.common import (_datetime_tuple as datetime_tuple, get_utc_time,
                            get_local_time, shell_split, _find_argument_quoted
                            as find_argument_quoted, _find_argument_unquoted as
                            find_argument_unquoted, parse_str_to_secs,
-                           parse_secs_to_str, safeJID)
+                           parse_secs_to_str, safeJID, unique_prefix_of)
 
 def test_utc_time():
     delta = timedelta(seconds=-3600)
@@ -63,3 +63,22 @@ def test_parse_secs_to_str():
 def test_safeJID():
     assert safeJID('toto@titi/tata') == JID('toto@titi/tata')
     assert safeJID('toto@…') == JID('')
+
+def test_unique_prefix_of__no_shared_prefix():
+    assert unique_prefix_of("a", "b") == "a"
+    assert unique_prefix_of("foo", "bar") == "f"
+    assert unique_prefix_of("foo", "") == "f"
+
+def test_unique_prefix_of__equal():
+    assert unique_prefix_of("foo", "foo") == "foo"
+
+def test_unique_prefix_of__a_prefix():
+    assert unique_prefix_of("foo", "foobar") == "foo"
+
+def test_unique_prefix_of__b_prefix():
+    assert unique_prefix_of("foobar", "foo") == "foob"
+
+def test_unique_prefix_of__normal_shared_prefix():
+    assert unique_prefix_of("foobar", "foobaz") == "foobar"
+    assert unique_prefix_of("fnord", "funky") == "fn"
+    assert unique_prefix_of("asbestos", "aspergers") == "asb"
diff --git a/test/test_tabs.py b/test/test_tabs.py
index 0a6930d4..6989bd67 100644
--- a/test/test_tabs.py
+++ b/test/test_tabs.py
@@ -183,3 +183,25 @@ def test_slice():
     tabs.append(dummy3)
 
     assert tabs[1:2][0] is dummy2
+
+def test_find_by_unique_prefix():
+    DummyTab.reset()
+    tabs = Tabs(h)
+    t1 = DummyTab()
+    t2 = DummyTab()
+    t3 = DummyTab()
+    tabs.append(t1)
+    tabs.append(t2)
+    tabs.append(t3)
+
+    t1.name = "foo"
+    t2.name = "bar"
+    t3.name = "fnord"
+
+    assert tabs.find_by_unique_prefix("f") == (True, None)
+    assert tabs.find_by_unique_prefix("b") == (True, t2)
+    assert tabs.find_by_unique_prefix("fo") == (True, t1)
+    assert tabs.find_by_unique_prefix("fn") == (True, t3)
+    assert tabs.find_by_unique_prefix("fx") == (False, None)
+    assert tabs.find_by_unique_prefix("x") == (False, None)
+    assert tabs.find_by_unique_prefix("") == (True, None)