import string
import color, mode2
from lex3 import Grammar, PatternRule, RegionRule
from method import Method, Argument
from point2 import Point

class HexGrammar(Grammar):
    rules = [
        PatternRule(r'zero', r"00"),
        PatternRule(r'byte', r'[0-f][0-f]'),
    ]

class Hex(mode2.Fundamental):
    grammar = HexGrammar
    colors = {
        'zero':      ('magenta', 'default'),
        'byte':      ('white', 'default'),
    }
    def __init__(self, w):
        mode2.Fundamental.__init__(self, w)

        self.add_action_and_bindings(GotoWord(), ('M-g',))
        self.add_action(FindStrings())
        self.add_action(WhichWord())

        # create all the insert actions for the basic text input
        for c in string.letters + string.digits + string.punctuation:
            if c in string.hexdigits:
                self.add_binding('overwrite-char-%s' % c.lower(), c)
            else:
                self.del_binding(c)

    def name(self):
        return "Hex"

class GotoWord(Method):
    '''Jump to the specified line number'''
    args = [Argument("wordno", type=type(0), prompt="Goto word: ")]
    def _execute(self, w, **vargs):
        n = vargs["wordno"]
        if n < 0:
            w.set_error("Negative word counts not supported.")
        try:
            x = (n % w.buffer.numwords) * (w.buffer.wordsize + 1)
            y = n / w.buffer.numwords
            p = Point(x, y)
            w.goto(p)
        except:
            w.goto_end()

class WhichWord(Method):
    '''Show the current word number'''
    def _execute(self, w, **vargs):
        cursor = w.logical_cursor()
        n = cursor.y * w.buffer.numwords
        n += cursor.x / (w.buffer.wordsize + 1)
        w.set_error("Currently in word %s (%s)" % (hex(n), n))

class FindStrings(Method):
    def _execute(self, w, **vargs):
        newlines = []
        lastline = ''
        i = 0
        for line in w.buffer.lines:
            lastc = None
            newline = ""
            for c in line:
                if c not in '0123456789abcdefABCDEF':                
                    lastc = None
                elif lastc is None:
                    lastc = c
                else:
                    char = chr(int(lastc + c, 16))
                    lastc = None
                    if char in string.whitespace:
                        newline += ' '
                    elif char in string.letters + string.digits + string.punctuation:
                        newline += char
                    else:
                        newline += '.'
            if lastc is not None:
                newline += '.'
            if i == 3:
                newlines.append(lastline)
                lastline = ''
            else:
                lastline += newline
            i = (i + 1) % 4
        w.application.data_buffer("*Strings*", '\n'.join(newlines), switch_to=True)