#   Copyright 2000-2004 Michael Hudson mwh@python.net
#
#                        All Rights Reserved
#
# Portions Copyright (c) 2005 Nokia Corporation 
#
# Permission to use, copy, modify, and distribute this software and
# its documentation for any purpose is hereby granted without fee,
# provided that the above copyright notice appear in all copies and
# that both that copyright notice and this permission notice appear in
# supporting documentation.
#
# THE AUTHOR MICHAEL HUDSON DISCLAIMS ALL WARRANTIES WITH REGARD TO
# THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
# AND FITNESS, IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL,
# INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER
# RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF
# CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
# CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

from pyrepl import reader, commands
from pyrepl.reader import Reader as R

isearch_keymap = tuple(
    [('\\%03o'%c, 'isearch-end') for c in range(256) if chr(c) != '\\'] + \
    [(c, 'isearch-add-character')
     for c in map(chr, range(32, 127)) if c != '\\'] + \
    [('\\%03o'%c, 'isearch-add-character')
     for c in range(256) if chr(c).isalpha() and chr(c) != '\\'] + \
    [('\\\\', 'self-insert'),
     (r'\C-r', 'isearch-backwards'),
     (r'\C-s', 'isearch-forwards'),
     (r'\C-c', 'isearch-cancel'),
     (r'\C-g', 'isearch-cancel'),
     (r'\<backspace>', 'isearch-backspace')])

del c

ISEARCH_DIRECTION_NONE = ''
ISEARCH_DIRECTION_BACKWARDS = 'r'
ISEARCH_DIRECTION_FORWARDS = 'f'

class next_history(commands.Command):
    def do(self):
        r = self.reader
        if r.historyi == len(r.history):
            r.error("end of history list")
            return
        r.select_item(r.historyi + 1)

class previous_history(commands.Command):
    def do(self):
        r = self.reader
        if r.historyi == 0:
            r.error("start of history list")
            return
        r.select_item(r.historyi - 1)

class restore_history(commands.Command):
    def do(self):
        r = self.reader
        if r.historyi != len(r.history):
            if r.get_unicode() != r.history[r.historyi]:
                r.buffer = list(r.history[r.historyi])
                r.pos = len(r.buffer)
                r.dirty = 1

class first_history(commands.Command):
    def do(self):
        self.reader.select_item(0)

class last_history(commands.Command):
    def do(self):
        self.reader.select_item(len(self.reader.history))

class operate_and_get_next(commands.FinishCommand):
    def do(self):
        self.reader.next_history = self.reader.historyi + 1

class yank_arg(commands.Command):
    def do(self):
        r = self.reader
        if r.last_command is self.__class__:
            r.yank_arg_i += 1
        else:
            r.yank_arg_i = 0
        if r.historyi <= r.yank_arg_i:
            r.error("beginning of history list")
            return
        a = r.get_arg(-1)
        # XXX how to split?
        words = r.get_item(r.historyi - r.yank_arg_i - 1).split()
        if a < -len(words) or a >= len(words):
            r.error("no such arg")
            return
        w = words[a]
        b = r.buffer
        if r.yank_arg_i > 0:
            o = len(r.yank_arg_yanked)
        else:
            o = 0
        b[r.pos - o:r.pos] = list(w)
        r.yank_arg_yanked = w
        r.pos += len(w) - o
        r.dirty = 1

class forward_history_isearch(commands.Command):
    def do(self):
        r = self.reader
        r.isearch_direction = ISEARCH_DIRECTION_FORWARDS
        r.isearch_start = r.historyi, r.pos
        r.isearch_term = ''
        r.dirty = 1
        r.push_input_trans(r.isearch_trans)
        

class reverse_history_isearch(commands.Command):
    def do(self):
        r = self.reader
        r.isearch_direction = ISEARCH_DIRECTION_BACKWARDS
        r.dirty = 1
        r.isearch_term = ''
        r.push_input_trans(r.isearch_trans)
        r.isearch_start = r.historyi, r.pos

class isearch_cancel(commands.Command):
    def do(self):
        r = self.reader
        r.isearch_direction = ISEARCH_DIRECTION_NONE
        r.pop_input_trans()
        r.select_item(r.isearch_start[0])
        r.pos = r.isearch_start[1]
        r.dirty = 1

class isearch_add_character(commands.Command):
    def do(self):
        r = self.reader
        b = r.buffer
        r.isearch_term += self.event[-1]
        r.dirty = 1
        p = r.pos + len(r.isearch_term) - 1
        if b[p:p+1] != [r.isearch_term[-1]]:
            r.isearch_next()

class isearch_backspace(commands.Command):
    def do(self):
        r = self.reader
        if len(r.isearch_term) > 0:
            r.isearch_term = r.isearch_term[:-1]
            r.dirty = 1
        else:
            r.error("nothing to rubout")

class isearch_forwards(commands.Command):
    def do(self):
        r = self.reader
        r.isearch_direction = ISEARCH_DIRECTION_FORWARDS
        r.isearch_next()

class isearch_backwards(commands.Command):
    def do(self):
        r = self.reader
        r.isearch_direction = ISEARCH_DIRECTION_BACKWARDS
        r.isearch_next()

class isearch_end(commands.Command):
    def do(self):
        r = self.reader
        r.isearch_direction = ISEARCH_DIRECTION_NONE
        r.console.forgetinput()
        r.pop_input_trans()
        r.dirty = 1
        r.isearch_previous_term = r.isearch_term

class HistoricalReader(R):
    """Adds history support (with incremental history searching) to the
    Reader class.

    Adds the following instance variables:
      * history:
        a list of strings
      * historyi:
      * transient_history:
      * next_history:
      * isearch_direction, isearch_term, isearch_start:
      * yank_arg_i, yank_arg_yanked:
        used by the yank-arg command; not actually manipulated by any
        HistoricalReader instance methods.
    """

    def collect_keymap(self):
        return super(HistoricalReader, self).collect_keymap() + (
            (r'\C-n', 'next-history'),
            (r'\C-p', 'previous-history'),
            (r'\C-o', 'operate-and-get-next'),
            (r'\C-r', 'reverse-history-isearch'),
            (r'\C-s', 'forward-history-isearch'),
            (r'\M-r', 'restore-history'),
            (r'\M-.', 'yank-arg'),
            (r'\<page down>', 'last-history'),
            (r'\<page up>', 'first-history'))


    def __init__(self, console):
        super(HistoricalReader, self).__init__(console)
        self.history = []
        self.historyi = 0
        self.transient_history = {}
        self.next_history = None
        self.isearch_direction = ISEARCH_DIRECTION_NONE
        self.isearch_previous_term = ''
        for c in [next_history, previous_history, restore_history,
                  first_history, last_history, yank_arg,
                  forward_history_isearch, reverse_history_isearch,
                  isearch_end, isearch_add_character, isearch_cancel,
                  isearch_add_character, isearch_backspace,
                  isearch_forwards, isearch_backwards, operate_and_get_next]:
            self.commands[c.__name__] = c
            self.commands[c.__name__.replace('_', '-')] = c
        from pyrepl import input
        self.isearch_trans = input.KeymapTranslator(
            isearch_keymap, invalid_cls=isearch_end,
            character_cls=isearch_add_character)
        
    def select_item(self, i):
        self.transient_history[self.historyi] = self.get_unicode()
        buf = self.transient_history.get(i)
        if buf is None:
            buf = self.history[i]
        self.buffer = list(buf)
        self.historyi = i
        self.pos = len(self.buffer)
        self.dirty = 1

    def get_item(self, i):
        assert i>=0 and i<=len(self.history)
        if i < len(self.history):
            return self.transient_history.get(i, self.history[i])
        else:
            return self.transient_history.get(i, self.get_unicode())

    def prepare(self):
        super(HistoricalReader, self).prepare()
        try:
            self.transient_history = {}
            if self.next_history is not None \
               and self.next_history < len(self.history):
                self.historyi = self.next_history
                self.buffer[:] = list(self.history[self.next_history])
                self.pos = len(self.buffer)
                self.transient_history[len(self.history)] = ''
            else:
                self.historyi = len(self.history)
            self.next_history = None
        except:
            self.restore()
            raise

    def get_prompt(self, lineno, cursor_on_line):
        if cursor_on_line and self.isearch_direction <> ISEARCH_DIRECTION_NONE:
            d = 'rf'[self.isearch_direction == ISEARCH_DIRECTION_FORWARDS]
            return "(%s-search `%s') "%(d, self.isearch_term)
        else:
            return super(HistoricalReader, self).get_prompt(lineno, cursor_on_line)

    def isearch_next(self):
        st = self.isearch_term
        # If the isearch key is pressed twice without entering anything,
        # try to use the previous search term, just like Emacs does it.
        if st == '': 
            self.isearch_term=st=self.isearch_previous_term
            if st=='':
                self.error("nothing to search")
                return
        p = self.pos
        i = self.historyi
        s = self.get_unicode()
        forwards = self.isearch_direction == ISEARCH_DIRECTION_FORWARDS
        while 1:
            if forwards:
                p = s.find(st, p + 1)
            else:
                p = s.rfind(st, 0, p + len(st) - 1)
            if p != -1:
                self.select_item(i)
                self.pos = p
                return
            elif ((forwards and i >= len(self.history) - 1)
                  or (not forwards and i == 0)):
                self.error("not found")
                return
            else:
                if forwards:
                    i += 1
                    s = self.get_item(i)
                    p = -1
                else:
                    i -= 1
                    s = self.get_item(i)
                    p = len(s)

    def finish(self):
        super(HistoricalReader, self).finish()
        ret = self.get_unicode()
        for i, t in self.transient_history.items():
            if i < len(self.history) and i != self.historyi:
                self.history[i] = t
        if ret:
            self.history.append(ret)

def test():
    from pyrepl.unix_console import UnixConsole
    reader = HistoricalReader(UnixConsole())
    reader.ps1 = "h**> "
    reader.ps2 = "h/*> "
    reader.ps3 = "h|*> "
    reader.ps4 = "h\*> "
    while reader.readline():
        pass

if __name__=='__main__':
    test()