#!/usr/bin/python
# -*- coding: utf-8 -*-
#
# Urwid escape sequences common to curses_display and raw_display
#    Copyright (C) 2004-2006  Ian Ward
#
#    This library is free software; you can redistribute it and/or
#    modify it under the terms of the GNU Lesser General Public
#    License as published by the Free Software Foundation; either
#    version 2.1 of the License, or (at your option) any later version.
#
#    This library is distributed in the hope that it will be useful,
#    but WITHOUT ANY WARRANTY; without even the implied warranty of
#    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
#    Lesser General Public License for more details.
#
#    You should have received a copy of the GNU Lesser General Public
#    License along with this library; if not, write to the Free Software
#    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
#
# Urwid web site: http://excess.org/urwid/

"""
Terminal Escape Sequences for input and display
"""

import os
import re

import encodings
utf8decode = lambda s: encodings.codecs.utf_8_decode(s)[0]

try:
    import str_util
except ImportError:
    import old_str_util as str_util

within_double_byte = str_util.within_double_byte

SO = "\x0e"
SI = "\x0f"

DEC_TAG = "0"
DEC_SPECIAL_CHARS = utf8decode("◆▒°±┘┐┌└┼⎺⎻─⎼⎽├┤┴┬│≤≥π≠£·")
ALT_DEC_SPECIAL_CHARS = u"`afgjklmnopqrstuvwxyz{|}~"

DEC_SPECIAL_CHARMAP = {}
assert len(DEC_SPECIAL_CHARS) == len(ALT_DEC_SPECIAL_CHARS), `DEC_SPECIAL_CHARS, ALT_DEC_SPECIAL_CHARS`
for c, alt in zip(DEC_SPECIAL_CHARS, ALT_DEC_SPECIAL_CHARS):
    DEC_SPECIAL_CHARMAP[ord(c)] = SO + alt + SI

SAFE_ASCII_DEC_SPECIAL_RE = re.compile(u"^[ -~%s]*$" % DEC_SPECIAL_CHARS)
DEC_SPECIAL_RE = re.compile(u"[%s]" % DEC_SPECIAL_CHARS)


###################
## Input sequences
###################

class MoreInputRequired(Exception):
    pass

def escape_modifier( digit ):
    mode = ord(digit) - ord("1")
    return "shift "*(mode&1) + "meta "*((mode&2)/2) + "ctrl "*((mode&4)/4)
    

input_sequences = [
    ('[A','up'),('[B','down'),('[C','right'),('[D','left'),
    ('[E','5'),('[F','end'),('[G','5'),('[H','home'),

    ('[1~','home'),('[2~','insert'),('[3~','delete'),('[4~','end'),
    ('[5~','page up'),('[6~','page down'),
    ('[7~','home'),('[8~','end'),

    ('[[A','f1'),('[[B','f2'),('[[C','f3'),('[[D','f4'),('[[E','f5'),
    
    ('[11~','f1'),('[12~','f2'),('[13~','f3'),('[14~','f4'),
    ('[15~','f5'),('[17~','f6'),('[18~','f7'),('[19~','f8'),
    ('[20~','f9'),('[21~','f10'),('[23~','f11'),('[24~','f12'),
    ('[25~','f13'),('[26~','f14'),('[28~','f15'),('[29~','f16'),
    ('[31~','f17'),('[32~','f18'),('[33~','f19'),('[34~','f20'),

    ('OA','up'),('OB','down'),('OC','right'),('OD','left'),
    ('OH','home'),('OF','end'),
    ('OP','f1'),('OQ','f2'),('OR','f3'),('OS','f4'),
    ('Oo','/'),('Oj','*'),('Om','-'),('Ok','+'),

    ('[Z','shift tab'),
] + [ 
    # modified cursor keys + home, end, 5 -- [#X and [1;#X forms
    (prefix+digit+letter, escape_modifier(digit) + key)
    for prefix in "[","[1;"
    for digit in "12345678"
    for letter,key in zip("ABCDEFGH",
        ('up','down','right','left','5','end','5','home'))
] + [ 
    # modified F1-F4 keys -- O#X form
    ("O"+digit+letter, escape_modifier(digit) + key)
    for digit in "12345678"
    for letter,key in zip("PQRS",('f1','f2','f3','f4'))
] + [ 
    # modified F1-F13 keys -- [XX;#~ form
    ("["+str(num)+";"+digit+"~", escape_modifier(digit) + key)
    for digit in "12345678"
    for num,key in zip(
        (11,12,13,14,15,17,18,19,20,21,23,24,25,26,28,29,31,32,33,34),
        ('f1','f2','f3','f4','f5','f6','f7','f8','f9','f10','f11',
        'f12','f13','f14','f15','f16','f17','f18','f19','f20'))
] + [
    # mouse reporting (special handling done in KeyqueueTrie)
    ('[M', 'mouse'),
    # report status response
    ('[0n', 'status ok')
]

class KeyqueueTrie(object):
    def __init__( self, sequences ):
        self.data = {}
        for s, result in sequences:
            assert type(result) != type({})
            self.add(self.data, s, result)
    
    def add(self, root, s, result):
        assert type(root) == type({}), "trie conflict detected"
        assert len(s) > 0, "trie conflict detected"
        
        if root.has_key(ord(s[0])):
            return self.add(root[ord(s[0])], s[1:], result)
        if len(s)>1:
            d = {}
            root[ord(s[0])] = d
            return self.add(d, s[1:], result)
        root[ord(s)] = result
    
    def get(self, keys, more_available):
        result = self.get_recurse(self.data, keys, more_available)
        if not result:
            result = self.read_cursor_position(keys, more_available)
        return result
    
    def get_recurse(self, root, keys, more_available):
        if type(root) != type({}):
            if root == "mouse":
                return self.read_mouse_info(keys, 
                    more_available)
            return (root, keys)
        if not keys:
            # get more keys
            if more_available:
                raise MoreInputRequired()
            return None
        if not root.has_key(keys[0]):
            return None
        return self.get_recurse(root[keys[0]], keys[1:], more_available)
    
    def read_mouse_info(self, keys, more_available):
        if len(keys) < 3:
            if more_available:
                raise MoreInputRequired()
            return None
        
        b = keys[0] - 32
        x, y = keys[1] - 33, keys[2] - 33  # start from 0
        
        prefix = ""
        if b & 4:    prefix = prefix + "shift "
        if b & 8:    prefix = prefix + "meta "
        if b & 16:    prefix = prefix + "ctrl "

        # 0->1, 1->2, 2->3, 64->4, 65->5
        button = ((b&64)/64*3) + (b & 3) + 1

        if b & 3 == 3:    
            action = "release"
            button = 0
        elif b & MOUSE_RELEASE_FLAG:
            action = "release"
        elif b & MOUSE_DRAG_FLAG:
            action = "drag"
        else:
            action = "press"

        return ( (prefix + "mouse " + action, button, x, y), keys[3:] )
    
    def read_cursor_position(self, keys, more_available):
        """
        Interpret cursor position information being sent by the
        user's terminal.  Returned as ('cursor position', x, y)
        where (x, y) == (0, 0) is the top left of the screen.
        """
        if not keys:
            if more_available:
                raise MoreInputRequired()
            return None
        if keys[0] != ord('['):
            return None
        # read y value
        y = 0
        i = 1
        for k in keys[i:]:
            i += 1
            if k == ord(';'):
                if not y:
                    return None
                break
            if k < ord('0') or k > ord('9'):
                return None
            if not y and k == ord('0'):
                return None
            y = y * 10 + k - ord('0')
        if not keys[i:]:
            if more_available:
                raise MoreInputRequired()
            return None
        # read x value
        x = 0
        for k in keys[i:]:
            i += 1
            if k == ord('R'):
                if not x:
                    return None
                return (("cursor position", x-1, y-1), keys[i:])
            if k < ord('0') or k > ord('9'):
                return None
            if not x and k == ord('0'):
                return None
            x = x * 10 + k - ord('0')
        if not keys[i:]:
            if more_available:
                raise MoreInputRequired()
        return None




# This is added to button value to signal mouse release by curses_display
# and raw_display when we know which button was released.  NON-STANDARD 
MOUSE_RELEASE_FLAG = 2048  

# xterm adds this to the button value to signal a mouse drag event
MOUSE_DRAG_FLAG = 32


#################################################
# Build the input trie from input_sequences list
input_trie = KeyqueueTrie(input_sequences)
#################################################

_keyconv = {
    -1:None,
    8:'backspace',
    9:'tab',
    10:'enter',
    13:'enter',
    127:'backspace',
    # curses-only keycodes follow..  (XXX: are these used anymore?)
    258:'down',
    259:'up',
    260:'left',
    261:'right',
    262:'home',
    263:'backspace',
    265:'f1', 266:'f2', 267:'f3', 268:'f4',
    269:'f5', 270:'f6', 271:'f7', 272:'f8',
    273:'f9', 274:'f10', 275:'f11', 276:'f12',
    277:'shift f1', 278:'shift f2', 279:'shift f3', 280:'shift f4',
    281:'shift f5', 282:'shift f6', 283:'shift f7', 284:'shift f8',
    285:'shift f9', 286:'shift f10', 287:'shift f11', 288:'shift f12',
    330:'delete',
    331:'insert',
    338:'page down',
    339:'page up',
    343:'enter',    # on numpad
    350:'5',        # on numpad
    360:'end',
}



def process_keyqueue(codes, more_available):
    """
    codes -- list of key codes
    more_available -- if True then raise MoreInputRequired when in the 
        middle of a character sequence (escape/utf8/wide) and caller 
        will attempt to send more key codes on the next call.
    
    returns (list of input, list of remaining key codes).
    """
    code = codes[0]
    if code >= 32 and code <= 126:
        key = chr(code)
        return [key], codes[1:]
    if _keyconv.has_key(code):
        return [_keyconv[code]], codes[1:]
    if code >0 and code <27:
        return ["ctrl %s" % chr(ord('a')+code-1)], codes[1:]
    if code >27 and code <32:
        return ["ctrl %s" % chr(ord('A')+code-1)], codes[1:]
    
    em = str_util.get_byte_encoding()
    
    if (em == 'wide' and code < 256 and  
        within_double_byte(chr(code),0,0)):
        if not codes[1:]:
            if more_available:
                raise MoreInputRequired()
        if codes[1:] and codes[1] < 256:
            db = chr(code)+chr(codes[1])
            if within_double_byte(db, 0, 1):
                return [db], codes[2:]
    if em == 'utf8' and code>127 and code<256:
        if code & 0xe0 == 0xc0: # 2-byte form
            need_more = 1
        elif code & 0xf0 == 0xe0: # 3-byte form
            need_more = 2
        elif code & 0xf8 == 0xf0: # 4-byte form
            need_more = 3
        else:
            return ["<%d>"%code], codes[1:]

        for i in range(need_more):
            if len(codes)-1 <= i:
                if more_available:
                    raise MoreInputRequired()
                else:
                    return ["<%d>"%code], codes[1:]
            k = codes[i+1]
            if k>256 or k&0xc0 != 0x80:
                return ["<%d>"%code], codes[1:]
        
        s = "".join([chr(c)for c in codes[:need_more+1]])
        try:
            return [s.decode("utf-8")], codes[need_more+1:]
        except UnicodeDecodeError:
            return ["<%d>"%code], codes[1:]
        
    if code >127 and code <256:
        key = chr(code)
        return [key], codes[1:]
    if code != 27:
        return ["<%d>"%code], codes[1:]

    result = input_trie.get(codes[1:], more_available)
    
    if result is not None:
        result, remaining_codes = result
        return [result], remaining_codes
    
    if codes[1:]:
        # Meta keys -- ESC+Key form
        run, remaining_codes = process_keyqueue(codes[1:], 
            more_available)
        if run[0] == "esc" or run[0].find("meta ") >= 0:
            return ['esc']+run, remaining_codes
        return ['meta '+run[0]]+run[1:], remaining_codes
        
    return ['esc'], codes[1:]


####################
## Output sequences
####################

ESC = "\x1b"

CURSOR_HOME = ESC+"[H"
CURSOR_HOME_COL = "\r"

APP_KEYPAD_MODE = ESC+"="
NUM_KEYPAD_MODE = ESC+">"

SWITCH_TO_ALTERNATE_BUFFER = ESC+"7"+ESC+"[?47h"
RESTORE_NORMAL_BUFFER = ESC+"[?47l"+ESC+"8"

#RESET_SCROLL_REGION = ESC+"[;r"
#RESET = ESC+"c"

REPORT_STATUS = ESC + "[5n"
REPORT_CURSOR_POSITION = ESC+"[6n"

INSERT_ON = ESC + "[4h"
INSERT_OFF = ESC + "[4l"

def set_cursor_position( x, y ):
    assert type(x) == type(0)
    assert type(y) == type(0)
    return ESC+"[%d;%dH" %(y+1, x+1)

def move_cursor_right(x):
    if x < 1: return ""
    return ESC+"[%dC" % x

def move_cursor_up(x):
    if x < 1: return ""
    return ESC+"[%dA" % x

def move_cursor_down(x):
    if x < 1: return ""
    return ESC+"[%dB" % x

HIDE_CURSOR = ESC+"[?25l"
SHOW_CURSOR = ESC+"[?25h"

MOUSE_TRACKING_ON = ESC+"[?1000h"+ESC+"[?1002h"
MOUSE_TRACKING_OFF = ESC+"[?1002l"+ESC+"[?1000l"

DESIGNATE_G1_SPECIAL = ESC+")0"


