poezio/src/windows/text_win.py

"""
TextWin, the window showing the text messages and info messages in poezio.
Can be locked, scrolled, has a separator, etc…
"""

import logging
log = logging.getLogger(__name__)

import curses
from math import ceil, log10

from . import Win, g_lock
from . base_wins import FORMAT_CHAR, Line
from . funcs import truncate_nick, parse_attrs

import poopt
from config import config
from theming import to_curses_attr, get_theme, dump_tuple


class TextWin(Win):
    def __init__(self, lines_nb_limit=None):
        if lines_nb_limit is None:
            lines_nb_limit = config.get('max_lines_in_memory')
        Win.__init__(self)
        self.lines_nb_limit = lines_nb_limit
        self.pos = 0
        self.built_lines = []   # Each new message is built and kept here.
        # on resize, we rebuild all the messages

        self.lock = False
        self.lock_buffer = []

        # the Lines of the highlights in that buffer
        self.highlights = []
        # the current HL position in that list NaN means that we’re not on
        # an hl. -1 is a valid position (it's before the first hl of the
        # list. i.e the separator, in the case where there’s no hl before
        # it.)
        self.hl_pos = float('nan')

        # Keep track of the number of hl after the separator.
        # This is useful to make “go to next highlight“ work after a “move to separator”.
        self.nb_of_highlights_after_separator = 0

        self.separator_after = None

    def toggle_lock(self):
        if self.lock:
            self.release_lock()
        else:
            self.acquire_lock()
        return self.lock

    def acquire_lock(self):
        self.lock = True

    def release_lock(self):
        for line in self.lock_buffer:
            self.built_lines.append(line)
        self.lock = False

    def next_highlight(self):
        """
        Go to the next highlight in the buffer.
        (depending on which highlight was selected before)
        if the buffer is already positionned on the last, of if there are no
        highlights, scroll to the end of the buffer.
        """
        log.debug('Going to the next highlight…')
        if (not self.highlights or self.hl_pos != self.hl_pos or
                self.hl_pos >= len(self.highlights) - 1):
            self.hl_pos = float('nan')
            self.pos = 0
            return
        hl_size = len(self.highlights) - 1
        if self.hl_pos < hl_size:
            self.hl_pos += 1
        else:
            self.hl_pos = hl_size
        log.debug("self.hl_pos = %s", self.hl_pos)
        hl = self.highlights[self.hl_pos]
        pos = None
        while not pos:
            try:
                pos = self.built_lines.index(hl)
            except ValueError:
                self.highlights = self.highlights[self.hl_pos+1:]
                if not self.highlights:
                    self.hl_pos = float('nan')
                    self.pos = 0
                    return
                self.hl_pos = 0
                hl = self.highlights[0]
        self.pos = len(self.built_lines) - pos - self.height
        if self.pos < 0 or self.pos >= len(self.built_lines):
            self.pos = 0

    def previous_highlight(self):
        """
        Go to the previous highlight in the buffer.
        (depending on which highlight was selected before)
        if the buffer is already positionned on the first, or if there are no
        highlights, scroll to the end of the buffer.
        """
        log.debug('Going to the previous highlight…')
        if not self.highlights or self.hl_pos <= 0:
            self.hl_pos = float('nan')
            self.pos = 0
            return
        if self.hl_pos != self.hl_pos:
            self.hl_pos = len(self.highlights) - 1
        else:
            self.hl_pos -= 1
        log.debug("self.hl_pos = %s", self.hl_pos)
        hl = self.highlights[self.hl_pos]
        pos = None
        while not pos:
            try:
                pos = self.built_lines.index(hl)
            except ValueError:
                self.highlights = self.highlights[self.hl_pos+1:]
                if not self.highlights:
                    self.hl_pos = float('nan')
                    self.pos = 0
                    return
                self.hl_pos = 0
                hl = self.highlights[0]
        self.pos = len(self.built_lines) - pos - self.height
        if self.pos < 0 or self.pos >= len(self.built_lines):
            self.pos = 0

    def scroll_up(self, dist=14):
        pos = self.pos
        self.pos += dist
        if self.pos + self.height > len(self.built_lines):
            self.pos = len(self.built_lines) - self.height
            if self.pos < 0:
                self.pos = 0
        return self.pos != pos

    def scroll_down(self, dist=14):
        pos = self.pos
        self.pos -= dist
        if self.pos <= 0:
            self.pos = 0
        return self.pos != pos

    def scroll_to_separator(self):
        """
        Scroll until separator is centered. If no separator is
        present, scroll at the top of the window
        """
        if None in self.built_lines:
            self.pos = len(self.built_lines) - self.built_lines.index(None) - self.height + 1
            if self.pos < 0:
                self.pos = 0
        else:
            self.pos = len(self.built_lines) - self.height + 1
        # Chose a proper position (not too high)
        self.scroll_up(0)
        # Make “next highlight” work afterwards. This makes it easy to
        # review all the highlights since the separator was placed, in
        # the correct order.
        self.hl_pos = len(self.highlights) - self.nb_of_highlights_after_separator - 1
        log.debug("self.hl_pos = %s", self.hl_pos)

    def remove_line_separator(self):
        """
        Remove the line separator
        """
        log.debug('remove_line_separator')
        if None in self.built_lines:
            self.built_lines.remove(None)
            self.separator_after = None

    def add_line_separator(self, room=None):
        """
        add a line separator at the end of messages list
        room is a textbuffer that is needed to get the previous message
        (in case of resize)
        """
        if None not in self.built_lines:
            self.built_lines.append(None)
            self.nb_of_highlights_after_separator = 0
            log.debug("Reseting number of highlights after separator")
            if room and room.messages:
                self.separator_after = room.messages[-1]

    def build_new_message(self, message, history=None, clean=True, highlight=False, timestamp=False):
        """
        Take one message, build it and add it to the list
        Return the number of lines that are built for the given
        message.
        """
        lines = self.build_message(message, timestamp=timestamp)
        if self.lock:
            self.lock_buffer.extend(lines)
        else:
            self.built_lines.extend(lines)
        if not lines or not lines[0]:
            return 0
        if highlight:
            self.highlights.append(lines[0])
            self.nb_of_highlights_after_separator += 1
            log.debug("Number of highlights after separator is now %s",
                          self.nb_of_highlights_after_separator)
        if clean:
            while len(self.built_lines) > self.lines_nb_limit:
                self.built_lines.pop(0)
        return len(lines)

    def build_message(self, message, timestamp=False):
        """
        Build a list of lines from a message, without adding it
        to a list
        """
        if message is None:  # line separator
            return [None]
        txt = message.txt
        if not txt:
            return []
        if len(message.str_time) > 8:
            default_color = (FORMAT_CHAR + dump_tuple(get_theme().COLOR_LOG_MSG)
                    + '}')
        else:
            default_color = None
        ret = []
        nick = truncate_nick(message.nickname)
        offset = 0
        if message.ack:
            offset += poopt.wcswidth(get_theme().CHAR_ACK_RECEIVED) + 1
        if nick:
            offset += poopt.wcswidth(nick) + 2 # + nick + '> ' length
        if message.revisions > 0:
            offset += ceil(log10(message.revisions + 1))
        if message.me:
            offset += 1 # '* ' before and ' ' after
        if timestamp:
            if message.str_time:
                offset += 1 + len(message.str_time)
            if get_theme().CHAR_TIME_LEFT and message.str_time:
                offset += 1
            if get_theme().CHAR_TIME_RIGHT and message.str_time:
                offset += 1
        lines = poopt.cut_text(txt, self.width-offset-1)
        prepend = ''
        attrs = []
        for line in lines:
            saved = Line(msg=message, start_pos=line[0], end_pos=line[1], prepend=prepend)
            attrs = parse_attrs(message.txt[line[0]:line[1]], attrs)
            if attrs:
                prepend = FORMAT_CHAR + FORMAT_CHAR.join(attrs)
            else:
                if default_color:
                    prepend = default_color
                else:
                    prepend = ''
            ret.append(saved)
        return ret

    def refresh(self):
        log.debug('Refresh: %s', self.__class__.__name__)
        if self.height <= 0:
            return
        if self.pos == 0:
            lines = self.built_lines[-self.height:]
        else:
            lines = self.built_lines[-self.height-self.pos:-self.pos]
        with_timestamps = config.get("show_timestamps")
        with g_lock:
            self._win.move(0, 0)
            self._win.erase()
            for y, line in enumerate(lines):
                if line:
                    msg = line.msg
                    if line.start_pos == 0:
                        if msg.nick_color:
                            color = msg.nick_color
                        elif msg.user:
                            color = msg.user.color
                        else:
                            color = None
                        if with_timestamps:
                            self.write_time(msg.str_time)
                        if msg.ack:
                            self.write_ack()
                        if msg.me:
                            self._win.attron(to_curses_attr(get_theme().COLOR_ME_MESSAGE))
                            self.addstr('* ')
                            self.write_nickname(msg.nickname, color, msg.highlight)
                            if msg.revisions:
                                self._win.attron(to_curses_attr(get_theme().COLOR_REVISIONS_MESSAGE))
                                self.addstr('%d' % msg.revisions)
                                self._win.attrset(0)
                            self.addstr(' ')
                        else:
                            self.write_nickname(msg.nickname, color, msg.highlight)
                            if msg.revisions:
                                self._win.attron(to_curses_attr(get_theme().COLOR_REVISIONS_MESSAGE))
                                self.addstr('%d' % msg.revisions)
                                self._win.attrset(0)
                            self.addstr('> ')
                if y != self.height-1:
                    self.addstr('\n')
            self._win.attrset(0)
            for y, line in enumerate(lines):
                if not line:
                    self.write_line_separator(y)
                else:
                    offset = 0
                    # Offset for the timestamp (if any) plus a space after it
                    if with_timestamps:
                        offset += len(line.msg.str_time)
                        if offset:
                            offset += 1

                    # Offset for the nickname (if any)
                    # plus a space and a > after it
                    if line.msg.nickname:
                        offset += poopt.wcswidth(
                                    truncate_nick(line.msg.nickname))
                        if line.msg.me:
                            offset += 3
                        else:
                            offset += 2
                        offset += ceil(log10(line.msg.revisions + 1))

                        if line.msg.ack:
                            offset += 1 + poopt.wcswidth(
                                        get_theme().CHAR_ACK_RECEIVED)

                    self.write_text(y, offset,
                            line.prepend+line.msg.txt[line.start_pos:line.end_pos])
                if y != self.height-1:
                    self.addstr('\n')
            self._win.attrset(0)
            self._refresh()

    def write_line_separator(self, y):
        char = get_theme().CHAR_NEW_TEXT_SEPARATOR
        self.addnstr(y, 0,
                char*((self.width//len(char) - 1)),
                self.width,
                to_curses_attr(get_theme().COLOR_NEW_TEXT_SEPARATOR))

    def write_text(self, y, x, txt):
        """
        write the text of a line.
        """
        self.addstr_colored(txt, y, x)

    def write_ack(self):
        color = get_theme().COLOR_CHAR_ACK
        self._win.attron(to_curses_attr(color))
        self.addstr(get_theme().CHAR_ACK_RECEIVED)
        self._win.attroff(to_curses_attr(color))
        self.addstr(' ')

    def write_nickname(self, nickname, color, highlight=False):
        """
        Write the nickname, using the user's color
        and return the number of written characters
        """
        if not nickname:
            return
        if highlight:
            hl_color = get_theme().COLOR_HIGHLIGHT_NICK
            if hl_color == "reverse":
                self._win.attron(curses.A_REVERSE)
            else:
                color = hl_color
        if color:
            self._win.attron(to_curses_attr(color))
        self.addstr(truncate_nick(nickname))
        if color:
            self._win.attroff(to_curses_attr(color))
        if highlight and hl_color == "reverse":
            self._win.attroff(curses.A_REVERSE)

    def write_time(self, time):
        """
        Write the date on the yth line of the window
        """
        if time:
            self.addstr(time)
            self.addstr(' ')

    def resize(self, height, width, y, x, room=None):
        with g_lock:
            if hasattr(self, 'width'):
                old_width = self.width
            else:
                old_width = None
            self._resize(height, width, y, x)
            if room and self.width != old_width:
                self.rebuild_everything(room)

            # reposition the scrolling after resize
            # (see #2450)
            buf_size = len(self.built_lines)
            if buf_size - self.pos < self.height:
                self.pos = buf_size - self.height
                if self.pos < 0:
                    self.pos = 0


    def rebuild_everything(self, room):
        self.built_lines = []
        with_timestamps = config.get('show_timestamps')
        for message in room.messages:
            self.build_new_message(message, clean=False, timestamp=with_timestamps)
            if self.separator_after is message:
                self.build_new_message(None)
        while len(self.built_lines) > self.lines_nb_limit:
            self.built_lines.pop(0)

    def modify_message(self, old_id, message):
        """
        Find a message, and replace it with a new one
        (instead of rebuilding everything in order to correct a message)
        """
        with_timestamps = config.get('show_timestamps')
        for i in range(len(self.built_lines)-1, -1, -1):
            if self.built_lines[i] and self.built_lines[i].msg.identifier == old_id:
                index = i
                while index >= 0 and self.built_lines[index] and self.built_lines[index].msg.identifier == old_id:
                    self.built_lines.pop(index)
                    index -= 1
                index += 1
                lines = self.build_message(message, timestamp=with_timestamps)
                for line in lines:
                    self.built_lines.insert(index, line)
                    index += 1
                break

    def __del__(self):
        log.debug('** TextWin: deleting %s built lines', (len(self.built_lines)))
        del self.built_lines