import re, string, struct
from subprocess import Popen, PIPE, STDOUT
import color, mode
from lex import Grammar, PatternRule, RegionRule
from method import Method, Argument
from point import Point

class HexSetByteOrder(Method):
    '''Sets the byte-order to use to 'little', 'big', or 'native' order'''
    args = [Argument("byteorder", type=type(''), prompt="Byte order: ")]
    def _execute(self, w, **vargs):
        order = vargs['byteorder']
        if order in w.mode.byteorders:
            w.mode.byteorder = order
            w.set_error("byte-order set to %r" % w.mode.byteorder)
        else:
            w.set_error("invalid ordering %r (use 'little', 'big', or 'native'")

class HexForward(Method):
    def _execute(self, w, **vargs):
        w.forward()
        end = w.buffer.get_buffer_end()
        while w.cursor_char().isspace() and w.cursor < end:
            w.forward()
class HexBackward(Method):
    def _execute(self, w, **vargs):
        w.backward()
        start = w.buffer.get_buffer_start()
        while w.cursor_char().isspace() and w.cursor > start:
            w.backward()

class HexForwardWord(Method):
    def _execute(self, w, **vargs):
        hf = w.application.methods['hex-forward']
        for i in range(0, w.buffer.wordsize * 2):
            hf.execute(w, **vargs)
class HexBackwardWord(Method):
    def _execute(self, w, **vargs):
        hb = w.application.methods['hex-backward']
        for i in range(0, w.buffer.wordsize * 2):
            hb.execute(w, **vargs)

class HexStartOfLine(Method):
    '''Move the cursor to the start of the current hex line'''
    def _execute(self, w, **vargs):
        w.start_of_line()
class HexEndOfLine(Method):
    '''Move the cursor to the end of the current hex line'''
    def _execute(self, w, **vargs):
        w.end_of_line()
        if w.cursor_char() == '\n':
            w.backward()

class HexRead(Method):
    _is_method = False
    def __init__(self, type_, fmt):
        self.name  = 'hex-read-%s' % type_.lower()
        self.type_ = type_
        self.fmt   = fmt
        self.size  = struct.calcsize(fmt)
        self.args  = []
        self.help  = "Read %r from address in the current buffer." % self.type_
    def _get_ix(self, b, cy, cx):
        ix = b.cursorx_to_datax(cy, cx)
        return ix
    def _execute(self, w, **vargs):
        b  = w.buffer
        hb = w.application.methods['hex-backward']
        (cx, cy) = w.cursor.xy()
        ix = self._get_ix(b, cy, cx)
        addr = b.get_address(cy, 0) + ix
        try:
            v = w.mode.read_struct(cy, ix, self.fmt, self.size)
            if v is None:
                w.set_error("not enough data to read %s" % self.type_)
            else:
                end = '%s-endian' % w.mode.byteorder
                w.set_error("%s %s at 0x%08x: %r" % (end, self.type_, addr, v))
        except Exception, e:
            w.set_error("%s could not be read at 0x%08x" % (self.type_, addr))
class HexReadAligned(HexRead):
    _is_method = False
    def __init__(self, type_, fmt):
        self.name  = 'hex-read-aligned-%s' % type_.lower()
        self.type_ = type_
        self.fmt   = fmt
        self.size  = struct.calcsize(fmt)
        self.args  = []
        self.help  = "Read %r from word-aligned address in the current buffer." % self.type_
    def _get_ix(self, b, cy, cx):
        ix = b.cursorx_to_datax(cy, cx)
        ix -= ix % b.wordsize
        return ix

class HexOverwriteChar(Method):
    _is_method = False
    def __init__(self, c):
        self.name = 'hex-overwrite-char-%s' % c
        self.args = []
        self.help = "Overwrite %r into the current hex buffer." % c
        self.char = c
    def _execute(self, w, **vargs):
        w.overwrite_char_at_cursor(self.char)
        end = w.buffer.get_buffer_end()
        while w.cursor_char().isspace() and w.cursor < end:
            w.forward()

class ShowX86Instruction(Method):
    ''''''
    size_re = re.compile(r'X86 insn \((\d+) bytes\):')
    def _execute(self, w, **vargs):
        disinst = w.application.config.get('hex.disinst')
        (cx, cy) = w.cursor.xy()
        ix = w.buffer.cursorx_to_datax(cy, cx)
        data = w.mode.read_data(cy, ix, 13)
        data = ''.join(['%02x' % ord(c) for c in data])
        try:
            p      = Popen((disinst, data), stdout=PIPE, stderr=STDOUT)
            lines  = [l.strip() for l in p.stdout.readlines()]
            result = p.wait()
            m = self.size_re.match(lines[0])
            assert m
            size = int(m.group(1))
            data = data[:size]
            w.set_error("%s %s" % (data, lines[1]))
        except Exception, e:
            w.set_error("there was an error")

class GotoAddress(Method):
    '''Jump to the specified line number'''
    args = [Argument("address", type=type(0), prompt="Goto address: ")]
    def _execute(self, w, **vargs):
        b = w.buffer
        addr = vargs["address"]
        if addr < 0:
            w.set_error("Negative address not supported.")
        ix = addr % (b.groupsize * b.numgroups)
        cx = w.buffer.datax_to_cursorx(ix)
        cy = addr // (b.groupsize * b.numgroups)
        w.goto(Point(cx, cy))
        w.set_error("Goto 0x%08x (%r, %r)" % (addr, cx, cy))

class ShowAddress(Method):
    '''Show the cursor's address in the current buffer'''
    def _execute(self, w, **vargs):
        (cx, cy) = w.cursor.xy()
        ix = w.buffer.cursorx_to_datax(cy, cx)
        addr = w.buffer.get_address(cy, ix)
        w.set_error("Cursor's address is 0x%08x" % addr)

class Hex(mode.Fundamental):
    modename = 'Hex'
    config = {
        'hex.disinst': 'disinst',
    }
    lmargin  = 12
    rmargin  = 18
    _ctrans  = ['.'] * 256
    byteorder = 'native'
    byteorders = {
        'native': '=',
        'little': '<',
        'big':    '>',
    }
    cgreen   = color.build('green', 'default', 'bold')
    ccyan    = color.build('cyan', 'default', 'bold')
    ccursor  = color.build('default', 'default', 'bold', 'reverse')
    for c in string.letters + string.digits + string.punctuation + ' ':
        _ctrans[ord(c)] = c
    ctrans = ''.join(_ctrans)
    actions = [HexForward, HexBackward, HexForwardWord, HexBackwardWord,
               HexStartOfLine, HexEndOfLine, ShowAddress, ShowX86Instruction,
               GotoAddress, HexSetByteOrder]
    def __init__(self, w):
        mode.Fundamental.__init__(self, w)
        self.bindings = {}

        self.add_bindings('center-view', ('C-l',))
        self.add_bindings('next-line', ('C-n', 'D_ARROW',))
        self.add_bindings('previous-line', ('C-p', 'U_ARROW',))
        self.add_bindings('next-section', ('M-n', 'M-D_ARROW',))
        self.add_bindings('previous-section', ('M-p', 'M-U_ARROW',))
        self.add_bindings('page-down', ('C-v', 'PG_DN',))
        self.add_bindings('page-up', ('M-v', 'PG_UP',))
        self.add_bindings('goto-beginning', ('M-<',))
        self.add_bindings('goto-end', ('M->',))
        self.add_bindings('right-word', ('M-f',))
        self.add_bindings('left-word', ('M-b',))
        self.add_bindings('set-mark', ('C-@',))
        self.add_bindings('switch-buffer', ('C-x b',))
        self.add_bindings('switch-mark', ('C-x C-x',))
        self.add_bindings('undo', ('C-/', 'C-x u',))
        self.add_bindings('redo', ('M-/', 'M-_', 'C-x r',))
        self.add_bindings('goto-line', ('M-g',))
        self.add_bindings('forward-chars', ('C-x M-c',))
        self.add_bindings('forward-lines', ('C-x M-n',))
        self.add_bindings('search', ('C-s',))
        self.add_bindings('reverse-search', ('C-r',))
        self.add_bindings('regex-search', ('M-C-s',))
        self.add_bindings('regex-reverse-search', ('M-C-r',))
        self.add_bindings('toggle-margins', ('M-m',))
        self.add_bindings('open-file', ('C-x C-f',))
        self.add_bindings('kill-buffer', ('C-x k',))
        self.add_bindings('list-buffers', ('C-x C-b',))
        self.add_bindings('meta-x', ('M-x',))
        self.add_bindings('save-buffer', ('C-x C-s',))
        self.add_bindings('save-buffer-as', ('C-x C-w',))
        self.add_bindings('exit', ('C-x C-c',))
        self.add_bindings('split-window', ('C-x s', 'C-x 2',))
        self.add_bindings('unsplit-window', ('C-u s', 'C-x 1',))
        self.add_bindings('toggle-window', ('C-x o',))
        self.add_bindings('open-console', ('M-e',))
        self.add_bindings('show-bindings-buffer', ('C-c M-h',))
        self.add_bindings('show-functions-buffer', ('C-c M-?',))
        self.add_bindings('which-command', ('M-h',))
        self.add_bindings('cmd-help-buffer', ('M-?',))
        self.add_bindings('set-mode', ('C-x m',))
        self.add_bindings('cancel', ('C-]',))
        self.add_bindings('exec', ('C-c e', 'C-c !'))
        self.add_bindings('grep', ('C-c g',))
        self.add_bindings('pipe', ('C-c p', 'C-c |'))
        self.add_bindings('view-buffer-parent', ('C-c .',))
        self.add_bindings('get-token', ('C-c t',))

        self.add_bindings('hex-forward', ('C-f', 'R_ARROW',))
        self.add_bindings('hex-backward', ('C-b', 'L_ARROW',))
        self.add_bindings('hex-forward-word', ('M-f', 'M-R_ARROW',))
        self.add_bindings('hex-backward-word', ('M-b', 'M-L_ARROW',))
        self.add_bindings('hex-start-of-line', ('C-a', 'HOME',))
        self.add_bindings('hex-end-of-line', ('C-e', 'END',))

        self.add_action_and_bindings(HexRead('char', 'b'), ('C-c b',))
        self.add_action_and_bindings(HexRead('uchar', 'B'), ('C-c B',))
        self.add_action_and_bindings(HexRead('short', 'h'), ('C-c h',))
        self.add_action_and_bindings(HexRead('ushort', 'H'), ('C-c H',))
        self.add_action_and_bindings(HexRead('int', 'i'), ('C-c i',))
        self.add_action_and_bindings(HexRead('uint', 'I'), ('C-c I',))
        self.add_action_and_bindings(HexRead('long', 'l'), ('C-c l',))
        self.add_action_and_bindings(HexRead('ulong', 'L'), ('C-c L',))
        self.add_action_and_bindings(HexRead('float', 'f'), ('C-c f',))
        self.add_action_and_bindings(HexRead('double', 'd'), ('C-c d',))

        self.add_action_and_bindings(HexReadAligned('char', 'b'), ('C-u b',))
        self.add_action_and_bindings(HexReadAligned('uchar', 'B'), ('C-u B',))
        self.add_action_and_bindings(HexReadAligned('short', 'h'), ('C-u h',))
        self.add_action_and_bindings(HexReadAligned('ushort', 'H'), ('C-u H',))
        self.add_action_and_bindings(HexReadAligned('int', 'i'), ('C-u i',))
        self.add_action_and_bindings(HexReadAligned('uint', 'I'), ('C-u I',))
        self.add_action_and_bindings(HexReadAligned('long', 'l'), ('C-u l',))
        self.add_action_and_bindings(HexReadAligned('ulong', 'L'), ('C-u L',))
        self.add_action_and_bindings(HexReadAligned('float', 'f'), ('C-u f',))
        self.add_action_and_bindings(HexReadAligned('double', 'd'), ('C-u d',))

        self.add_bindings('show-address', ('C-c a',))
        self.add_bindings('show-x86-instruction', ('C-c x',))
        self.add_bindings('goto-address', ('C-c M-g',))

        # 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_action_and_bindings(HexOverwriteChar(c), (c,))

    def get_address(self, y, x):
        return (y * 16) + x

    def get_lmargin(self, y, x=0, ended=False, cont=False):
        lm = self.lmargin
        if ended:
            s = '  --------  '
        else:
            addr = self.get_address(y, x)
            s = '0x%08x  ' % addr
        return ((0, s, self.ccyan),)

    def get_rmargin(self, y, x=0, ended=False, cont=False):
        if ended:
            return ((0, '', 0),)
        else:
            (cx, cy) = self.window.cursor.xy()
            s = string.translate(self.window.buffer.rawdata[y], self.ctrans)
            if cy == y:
                i = self.window.buffer.cursorx_to_datax(cy, cx)
                
                if i is None:
                    rmargins = ((0, s, self.cgreen),)
                elif i < len(s):
                    rmargins = ((0, s[0:i], self.cgreen),
                                (i, s[i], self.ccursor),
                                (i + 1, s[i+1:], self.cgreen))
                else:
                    rmargins= ((0, s[0:i], self.cgreen),
                               (i, s[i], self.cgreen),)
                return rmargins
            else:
                return ((0, s, self.cgreen),)

    def read_data(self, cy, ix, size):
        b  = self.window.buffer
        s = b.rawdata[cy][ix:]
        if len(s) < size:
            if cy < len(b.rawdata) - 1:
                s += b.rawdata[cy + 1]
        s = s[:size]
        return s
    def read_struct(self, cy, ix, fmt, size):
        s = self.read_data(cy, ix, size)
        fmt = '%s%s' % (self.byteorders[self.byteorder], fmt)
        return struct.unpack(fmt, s)[0]

install = Hex.install