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# Source code for fabio.fabioutils

    """
    General purpose utilities functions for fabio
    """
    from __future__ import with_statement
    import re, os, logging, threading, sys
    import StringIO as stringIO
    logger = logging.getLogger("fabioutils")
    from compression import bz2, gzip
    import traceback
    from math import ceil

    FILETYPES = {
        # extension NNNimage fabioclass
        # type consistency - always use a list if one case is
        'edf'    : ['edf'],
        'cor'    : ['edf'],
        'pnm'    : ['pnm'],
        'pgm'    : ['pnm'],
        'pbm'    : ['pnm'],
        'tif'    : ['tif'],
        'tiff'   : ['tif'],
        'img'    : ['adsc', 'OXD', 'HiPiC'],
        'mccd'   : ['marccd'],
        'mar2300': ['mar345'],
        'sfrm'   : ['bruker100'],
        'msk'    : ['fit2dmask'],
        'spr'    : ['fit2dspreadsheet'],
        'dm3'    : ['dm3'],
        'kcd'    : ['kcd'],
        'cbf'    : ['cbf'],
        'xml'    : ["xsd"],
        'xsd'    : ["xsd"],
                 }

    # Add bzipped and gzipped
    for key in FILETYPES.keys():
        FILETYPES[key + ".bz2"] = FILETYPES[key]
        FILETYPES[key + ".gz"] = FILETYPES[key]

    # Compressors

    COMPRESSORS = {}

    dictAscii = {None:[chr(i) for i in range(32, 127)],
               }

    try:
        lines = os.popen("gzip -h 2>&1").read()
        # Looking for "usage"
        if "sage" in lines:
            COMPRESSORS['.gz'] = 'gzip -dc '
        else:
            COMPRESSORS['.gz'] = None
    except Exception:
        COMPRESSORS['.gz'] = None

    try:
        lines = os.popen("bzip2 -h 2>&1").read()
        # Looking for "usage"
        if "sage" in lines:
            COMPRESSORS['.bz2'] = 'bzip2 -dc '
        else:
            COMPRESSORS['.bz2'] = None
    except Exception:
        COMPRESSORS['.bz2'] = None

    def deprecated(func):
        """
        used to deprecate a function/method: prints a lot of warning messages to enforce the modifaction of the code
        """
        def wrapper(*arg, **kw):
            """
            decorator that deprecates the use of a function
            """
            logger.warning("%s is Deprecated !!! %s" % (func.func_name, os.linesep.join([""] + traceback.format_stack()[:-1])))
            return func(*arg, **kw)
        return wrapper

    def pad(mystr, pattern=" ", size=80):
        """
        Performs the padding of the string to the right size with the right pattern
        """
        size = int(size)
        padded_size = int(ceil(float(len(mystr)) / size) * size)
        if len(pattern) == 1:
            return mystr.ljust(padded_size, pattern)
        else:
            return (mystr + pattern * int(ceil(float(padded_size - len(mystr)) / len(pattern))))[:padded_size]

    def getnum(name):
        """
        # try to figure out a file number
        # guess it starts at the back
        """
        stem , num, post_num = numstem(name)
        try:
            return int(num)
        except ValueError:
            return None

    class FilenameObject(object):
        """
        The 'meaning' of a filename ...
        """
        def __init__(self, stem=None,
                num=None,
                directory=None,
                format=None,
                extension=None,
                postnum=None,
                digits=4,
                filename=None):
            """
            This class can either be instanciated by a set of parameters like  directory, prefix, num, extension, ...

            @param stem: the stem is a kind of prefix (str)
            @param num: image number in the serie (int)
            @param directory: name of the directory (str)
            @param format: ??
            @param extension:
            @param postnum:
            @param digits: Number of digits used to print num

            Alternative constructor:

            @param filename: fullpath of an image file to be deconstructed into directory, prefix, num, extension, ...

            """

            self.stem = stem
            self.num = num
            self.format = format
            self.extension = extension
            self.digits = digits
            self.postnum = postnum
            self.directory = directory
            self.compressed = None
            if filename is not None:
                self.deconstruct_filename(filename)

        def str(self):
            """ Return a string representation """
            fmt = "stem %s, num %s format %s extension %s " + \
                    "postnum = %s digits %s dir %s"
            return fmt % tuple([str(x) for x in [
                        self.stem ,
                        self.num ,
                        self.format ,
                        self.extension ,
                        self.postnum ,
                        self.digits ,
                        self.directory ] ])
        __repr__ = str

        def tostring(self):
            """
            convert yourself to a string
            """
            name = self.stem
            if self.digits is not None and self.num is not None:
                fmt = "%0" + str(self.digits) + "d"
                name += fmt % self.num
            if self.postnum is not None:
                name += self.postnum
            if self.extension is not None:
                name += self.extension
            if self.directory is not None:
                name = os.path.join(self.directory, name)
            return name

        def deconstruct_filename(self, filename):
            """
            Break up a filename to get image type and number
            """
            direc, name = os.path.split(filename)
            direc = direc or None
            parts = name.split(".")
            compressed = False
            stem = parts[0]
            extn = ""
            postnum = ""
            ndigit = 4
            num = None
            typ = None
            if parts[-1] in ["gz", "bz2"]:
                extn = "." + parts[-1]
                parts = parts[:-1]
                compressed = True
            if parts[-1] in FILETYPES.keys():
                typ = FILETYPES[parts[-1]]
                extn = "." + parts[-1] + extn
                try:
                    stem, numstring, postnum = numstem(".".join(parts[:-1]))
                    num = int(numstring)
                    ndigit = len(numstring)
                except Exception, err:
                    # There is no number - hence make num be None, not 0
                    logger.debug("l176: %s" % err)
                    num = None
                    stem = "".join(parts[:-1])
            else:
                # Probably two type left
                if len(parts) == 1:
                    # Probably GE format stem_numb
                    parts2 = parts[0].split("_")
                    if parts2[-1].isdigit():
                        num = int(parts2[-1])
                        ndigit = len(parts2[-1])
                        typ = ['GE']
                        stem = "_".join(parts2[:-1]) + "_"
                else:
                    try:
                        num = int(parts[-1])
                        ndigit = len(parts[-1])
                        typ = ['bruker']
                        stem = ".".join(parts[:-1]) + "."
                    except Exception, err:
                        logger.debug("l196: %s" % err)
                        typ = None
                        extn = "." + parts[-1] + extn
                        numstring = ""
                        try:
                            stem , numstring, postnum = numstem(".".join(parts[:-1]))
                        except Exception, err:
                            logger.debug("l202: %s" % err)
                            raise
                        if numstring.isdigit():
                            num = int(numstring)
                            ndigit = len(numstring)
                    #            raise Exception("Cannot decode "+filename)

            self.stem = stem
            self.num = num
            self.directory = direc
            self.format = typ
            self.extension = extn
            self.postnum = postnum
            self.digits = ndigit
            self.compressed = compressed

    def numstem(name):
        """ cant see how to do without reversing strings
        Match 1 or more digits going backwards from the end of the string
        """
        reg = re.compile(r"^(.*?)(-?[0-9]{0,9})(\D*)$")
        #reg = re.compile("""(\D*)(\d\d*)(\w*)""")
        try:
            res = reg.match(name).groups()
            #res = reg.match(name[::-1]).groups()
            #return [ r[::-1] for r in res[::-1]]
            if len(res[0]) == len(res[1]) == 0: # Hack for file without number
                return [res[2], '', '']
            return [ r for r in res]
        except AttributeError: # no digits found
            return [name, "", ""]

    #@deprecated
    def deconstruct_filename(filename):
        """
        Function for backward compatibility.
        Deprecated
        """
        return FilenameObject(filename=filename)

    def construct_filename(filename, frame=None):
        "Try to construct the filename for a given frame"
        fobj = FilenameObject(filename=filename)
        if frame is not None:
            fobj.num = frame
        return fobj.tostring()

    def next_filename(name, padding=True):
        """ increment number """
        fobj = FilenameObject(filename=name)
        fobj.num += 1
        if not padding:
            fobj.digits = 0
        return fobj.tostring()

    def previous_filename(name, padding=True):
        """ decrement number """
        fobj = FilenameObject(filename=name)
        fobj.num -= 1
        if not padding:
            fobj.digits = 0
        return fobj.tostring()

    def jump_filename(name, num, padding=True):
        """ jump to number """
        fobj = FilenameObject(filename=name)
        fobj.num = num
        if not padding:
            fobj.digits = 0
        return fobj.tostring()

    def extract_filenumber(name):
        """ extract file number """
        fobj = FilenameObject(filename=name)
        return fobj.num

    def isAscii(name, listExcluded=None):
        """
        @param name: string to check
        @param listExcluded: list of char or string excluded.
        @return: True of False whether  name is pure ascii or not
        """
        isascii = None
        try:
            name.decode("ascii")
        except UnicodeDecodeError:
            isascii = False
        else:
            if listExcluded:
                isascii = not(any(bad in  name for bad in listExcluded))
            else:
                isascii = True
        return isascii

    def toAscii(name, excluded=None):
        """
        @param name: string to check
        @param excluded: tuple of char or string excluded (not list: they are mutable).
        @return: the name with all non valid char removed
        """
        if excluded not in dictAscii:
            ascii = dictAscii[None][:]
            for i in excluded:
                if i in ascii:
                    ascii.remove(i)
                else:
                    logger.error("toAscii: % not in ascii table" % i)
            dictAscii[excluded] = ascii
        else:
            ascii = dictAscii[excluded]
        out = [i for i in str(name) if i in ascii]
        return "".join(out)

    def nice_int(s):
        """
        Workaround that int('1.0') raises an exception

        @param s: string to be converted to integer
        """
        try:
            return int(s)
        except ValueError:
            return int(float(s))

    class StringIO(stringIO.StringIO):
        """
        just an interface providing the name and mode property to a StringIO

        BugFix for MacOSX mainly
        """
        def __init__(self, data, fname=None, mode="r"):
            stringIO.StringIO.__init__(self, data)
            self.closed = False
            if fname == None:
                self.name = "fabioStream"
            else:
                self.name = fname
            self.mode = mode
            self.lock = threading.Semaphore()
            self.__size = None

        def getSize(self):
            if self.__size is None:
                logger.debug("Measuring size of %s" % self.name)
                with self.lock:
                    pos = self.tell()
                    self.seek(0, os.SEEK_END)
                    self.__size = self.tell()
                    self.seek(pos)
            return self.__size
        def setSize(self, size):
            self.__size = size
        size = property(getSize, setSize)

    class File(file):
        """
        wrapper for "file" with locking
        """
        def __init__(self, name, mode="rb", buffering=0):
            """file(name[, mode[, buffering]]) -> file object

            Open a file.  The mode can be 'r', 'w' or 'a' for reading (default),
            writing or appending.  The file will be created if it doesn't exist
            when opened for writing or appending; it will be truncated when
            opened for writing.  Add a 'b' to the mode for binary files.
            Add a '+' to the mode to allow simultaneous reading and writing.
            If the buffering argument is given, 0 means unbuffered, 1 means line
            buffered, and larger numbers specify the buffer size.  The preferred way
            to open a file is with the builtin open() function.
            Add a 'U' to mode to open the file for input with universal newline
            support.  Any line ending in the input file will be seen as a '\n'
            in Python.  Also, a file so opened gains the attribute 'newlines';
            the value for this attribute is one of None (no newline read yet),
            '\r', '\n', '\r\n' or a tuple containing all the newline types seen.

            'U' cannot be combined with 'w' or '+' mode.
            """
            file.__init__(self, name, mode, buffering)
            self.lock = threading.Semaphore()
            self.__size = None
        def getSize(self):
            if self.__size is None:
                logger.debug("Measuring size of %s" % self.name)
                with self.lock:
                    pos = self.tell()
                    self.seek(0, os.SEEK_END)
                    self.__size = self.tell()
                    self.seek(pos)
            return self.__size
        def setSize(self, size):
            self.__size = size
        def __exit__(self, *args, **kwargs):
            """
            Close the file.
            """
            return file.close(self)
        def __enter__(self, *args, **kwargs):
            return self
        size = property(getSize, setSize)

    class UnknownCompressedFile(File):
        """
        wrapper for "File" with locking
        """
        def __init__(self, name, mode="rb", buffering=0):
            logger.warning("No decompressor found for this type of file (are gzip anf bz2 installed ???")
            File.__init__(self, name, mode, buffering)

    if gzip is None:
        GzipFile = UnknownCompressedFile
    else:
        class GzipFile(gzip.GzipFile):
            """
            Just a wrapper forgzip.GzipFile providing the correct seek capabilities for python 2.5
            """
            def __init__(self, filename=None, mode=None, compresslevel=9, fileobj=None):
                """
                Wrapper with locking for constructor for the GzipFile class.

                At least one of fileobj and filename must be given a
                non-trivial value.

                The new class instance is based on fileobj, which can be a regular
                file, a StringIO object, or any other object which simulates a file.
                It defaults to None, in which case filename is opened to provide
                a file object.

                When fileobj is not None, the filename argument is only used to be
                included in the gzip file header, which may includes the original
                filename of the uncompressed file.  It defaults to the filename of
                fileobj, if discernible; otherwise, it defaults to the empty string,
                and in this case the original filename is not included in the header.

                The mode argument can be any of 'r', 'rb', 'a', 'ab', 'w', or 'wb',
                depending on whether the file will be read or written.  The default
                is the mode of fileobj if discernible; otherwise, the default is 'rb'.
                Be aware that only the 'rb', 'ab', and 'wb' values should be used
                for cross-platform portability.

                The compresslevel argument is an integer from 1 to 9 controlling the
                level of compression; 1 is fastest and produces the least compression,
                and 9 is slowest and produces the most compression.  The default is 9.
                """
                gzip.GzipFile.__init__(self, filename, mode, compresslevel, fileobj)
                self.lock = threading.Semaphore()
                self.__size = None

            if sys.version_info < (2, 7):
                def getSize(self):
                    if self.__size is None:
                        logger.debug("Measuring size of %s" % self.name)
                        with open(self.filename, "rb") as f:
                            f.seek(-4)
                            self.__size = numpy.fromstring(f.read(4), dtype=numpy.uint32)
                    return self.__size
                def setSize(self, value):
                    self.__size = value
                size = property(getSize, setSize)
                @property
                def closed(self):
                    return self.fileobj is None

                def seek(self, offset, whence=os.SEEK_SET):
                    """
                    Move to new file position.

                    Argument offset is a byte count.  Optional argument whence defaults to
                    0 (offset from start of file, offset should be >= 0); other values are 1
                    (move relative to current position, positive or negative), and 2 (move
                    relative to end of file, usually negative, although many platforms allow
                    seeking beyond the end of a file).  If the file is opened in text mode,
                    only offsets returned by tell() are legal.  Use of other offsets causes
                    undefined behavior.

                    This is a wrapper for seek to ensure compatibility with old python 2.5
                    """
                    if whence == os.SEEK_SET:
                        gzip.GzipFile.seek(self, offset)
                    elif whence == os.SEEK_CUR:
                        gzip.GzipFile.seek(self, offset + self.tell())
                    elif whence == os.SEEK_END:
                        gzip.GzipFile.seek(self, -1)
                        gzip.GzipFile.seek(self, offset + self.tell())
                def __enter__(self, *args, **kwargs):
                    return self
                def __exit__(self, *args, **kwargs):
                    """
                    Close the file.
                    """
                    return gzip.GzipFile.close(self)

    if bz2 is None:
        BZ2File = UnknownCompressedFile
    else:
        class BZ2File(bz2.BZ2File):
            "Wrapper with lock"
            def __init__(self, name , mode='r', buffering=0, compresslevel=9):
                """
                BZ2File(name [, mode='r', buffering=0, compresslevel=9]) -> file object

                Open a bz2 file. The mode can be 'r' or 'w', for reading (default) or
                writing. When opened for writing, the file will be created if it doesn't
                exist, and truncated otherwise. If the buffering argument is given, 0 means
                unbuffered, and larger numbers specify the buffer size. If compresslevel
                is given, must be a number between 1 and 9.

                Add a 'U' to mode to open the file for input with universal newline
                support. Any line ending in the input file will be seen as a '\n' in
                Python. Also, a file so opened gains the attribute 'newlines'; the value
                for this attribute is one of None (no newline read yet), '\r', '\n',
                '\r\n' or a tuple containing all the newline types seen. Universal
                newlines are available only when reading.
                """
                bz2.BZ2File.__init__(self, name , mode, buffering, compresslevel)
                self.lock = threading.Semaphore()
                self.__size = None
            def getSize(self):
                if self.__size is None:
                    logger.debug("Measuring size of %s" % self.name)
                    with self.lock:
                        pos = self.tell()
                        all = self.read()
                        self.__size = self.tell()
                        self.seek(pos)
                return self.__size
            def setSize(self, value):
                self.__size = value
            size = property(getSize, setSize)
            def __exit__(self, *args, **kwargs):
                    """
                    Close the file.
                    """
                    return bz2.BZ2File.close(self)
            def __enter__(self, *args, **kwargs):
                return self

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