client = None

class Buffer:
    viewsize = 8

    def __init__(self):
        self.buf = []
        self.curline = 0
        self.edit = False

bufs = {}

def mod_init(cl):
    global client
    client = cl

def getnick(user):
    return user.split('!')[0]

def getwindow(buf):
    bi = buf.curline - (buf.viewsize-1)/2
    bs = buf.curline + buf.viewsize/2 + 1

    if bs > len(buf.buf):
        bi = bi - (bs - len(buf.buf))
        bs = len(buf.buf)
    if bi < 0:
        bi = 0

    return range(bi, bs)


def on_privchat(who, msg):
    nick = getnick(who)
    if nick not in bufs:
        bufs[nick] = Buffer()
    b = bufs[nick]

    if msg[0] == '.':
        args = msg[1:].split()
        cmd = args[0]

        if cmd == "l":
            if len(args) > 1:
                b.curline = int(args[1])

            if b.curline > len(b.buf):
                b.curline = len(b.buf)
            if b.curline < 0:
                b.curline = 0

            for i in getwindow(b):
                if i == b.curline:
                    client.sendto(nick, '----')
                client.sendto(nick, '%3d: '%i + b.buf[i])
            if b.curline == len(b.buf):
                    client.sendto(nick, '----')

        if cmd == "e":
            if b.edit is True:
                b.edit = False
            else:
                b.edit = True

        if cmd == "d":
            if len(args) < 2:
                return
            if len(args) > 2:
                for i in range(int(args[1]), int(args[2])+1):
                    b.buf.pop(int(args[1]))
            else:
                b.buf.pop(int(args[1]))

    else:
        if b.edit is True:
            b.buf.insert(b.curline, msg)
            b.curline = b.curline + 1