"""This module co-ordinates the reading of the source file.

    It maintains the current position of the parser in the source file.

    (c) Copyright by Jay Love, 2000 (mailto:jsliv@jslove.org)

    Permission to use, copy, modify, and distribute this software and its
    documentation for any purpose and without fee or royalty is hereby granted,
    provided that the above copyright notice appear in all copies and that
    both that copyright notice and this permission notice appear in
    supporting documentation or portions thereof, including modifications,
    that you make.

    THE AUTHORS DISCLAIM ALL WARRANTIES WITH REGARD TO
    THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
    FITNESS, IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL,
    INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING
    FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
    NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION
    WITH THE USE OR PERFORMANCE OF THIS SOFTWARE !

    This software is based in part on work done by the Jakarta group.

"""

from Context import *

import copy
import os


class Mark:
    """The Mark class marks a point in an input stream."""

    def __init__(self, reader, fileid=None, stream=None, inBaseDir=None, encoding=None):

        if isinstance(reader, StreamReader):
            self.reader = reader
            self.fileid = fileid
            self.includeStack = []
            self.cursor = 0
            self.stream = stream
            self.baseDir = inBaseDir
            self.encoding = encoding
        else:
            self = copy.copy(reader)
        # I think the includeStack will be copied correctly,
        # but check here for problems: raise Error('clone include stack')
        # JSP has an equals function, but I don't think I need that,
        # because of using copy, but maybe I do.

    def getFile(self):
        return self.reader.getFile(self.fileid)

    def __str__(self):
        return self.getFile() + '(' + str(self.line) + str(self.col) + ')'

    def __repr__(self):
        return self.getFile() + '(' + str(self.col) + ')'

    def pushStream(self, infileid, inStream, inBaseDir, inEncoding):
        self.includeStack.append((self.cursor, self.fileid, self.baseDir, self.encoding, self.stream))
        self.cursor = 0
        self.fileid = infileid
        self.baseDir = inBaseDir
        self.encoding = inEncoding
        self.stream = inStream

    def popStream(self):
        if len(self.includeStack) == 0:
            return 0 # false
        list = self.includeStack[len(self.includeStack)-1]
        del self.includeStack[len(self.includeStack)-1]
        self.cursor = list[0]
        self.fileid = list[1]
        self.baseDir = list[2]
        self.encoding = list[3]
        self.stream = list[4]
        return 1 # true


class StreamReader:
    """This class handles the PSP source file.

    It provides the characters to the other parts of the system.
    It can move forward and backwards in a file and remember locactions.

    """

    def __init__(self, filename, ctxt):
        self._pspfile = filename
        self._ctxt = ctxt
        self._filehandle = None
        self.sourcefiles = []
        self.current = None
        self.master = None

    def init(self):
        self.pushFile(self._ctxt.getFullPspFileName())

    def registerSourceFile(self, file):
        self.sourcefiles.append(file)
        return len(self.sourcefiles) - 1

    def pushFile(self, file, encoding=None):
        assert type(file) == type('')
        # if type(file) != type(''):
        # we've got an open file handle - don't think this case exists
        # Don't know what this master stuff is, but until I do, implement it.
        # Oh, it's the original file.
        if self.master is None:
            parent = None
            self.master = file
        else:
            parent = os.path.split(self.master)[0]
        isAbsolute = os.path.isabs(file)
        if parent is not None and not isAbsolute:
            file = os.path.join(parent, file)
        fileid = self.registerSourceFile(file)
        handle = open(file, 'r')
        stream = handle.read()
        handle.seek(0, 0)
        lines = handle.readlines()
        z = 0
        for i in lines:
            lines[z] = i.replace('\r\n', '\n').replace('\r', '\n')
            z += 1
        stream = ''.join(lines)

        if self.current is None:
            self.current = Mark(self, fileid, stream,
                self._ctxt.getBaseUri(), encoding)
        else:
            self.current.pushStream(fileid, stream,
                self._ctxt.getBaseUri(), encoding) # don't use yet

    def popFile(self):
        if self.current is None:
            return 0
        return self.current.popStream()

    def getFile(self, i):
        return self.sourcefiles[i]

    def newSourceFile(self, filename):
        if filename in self.sourcefiles:
            return None
        self.sourcefiles.append(filename)
        return len(self.sourcefiles)

    def Mark(self):
        return copy.copy(self.current)

    def skipUntil(self, st):
        """Greedy search.

        Return the point before the string, but move reader past it.

        """
        pt = self.current.stream.find(st, self.current.cursor)
        if pt == -1:
            self.current.cursor = len(self.current.stream)
            if self.hasMoreInput():
                self.popFile() # @@ Should I do this here? 6/1/00
                self.skipUntil(st)
            else:
                raise EOFError
        else:
            self.current.cursor = pt
            ret = self.Mark()
            self.current.cursor += len(st)
            return ret

    def reset(self, mark):
        self.current = mark

    def Matches(self, st):
        if st == self.current.stream[
                self.current.cursor:self.current.cursor+len(st)]:
            return 1
        return 0

    def Advance(self, length):
        """Advance length characters"""
        if length + self.current.cursor <= len(self.current.stream):
            self.current.cursor += length
        else:
            prog = len(self.current.stream) - self.current.cursor
            self.current.cursor = len(self.current.stream)
            if self.hasMoreInput():
                self.Advance(length-prog)
            else:
                raise EOFError()

    def nextChar(self):
        if self.hasMoreInput() == 0:
            return -1
        ch = self.current.stream[self.current.cursor]
        self.Advance(1)
        return ch

    def isSpace(self):
        """No advancing."""
        return self.current.stream[self.current.cursor] == ' ' \
            or self.current.stream[self.current.cursor] == '\n'

    def isDelimiter(self):
        if not self.isSpace():
            ch = self.peekChar()
            # Look for single character work delimiter:
            if ch == '=' or ch == '\"' or ch == "'" or ch == '/':
                return 1
            # Look for end of comment or basic end tag:
            if ch == '-':
                mark = self.Mark()
                ch = self.nextChar()
                ch2 = self.nextChar()
                if ch == '>' or (ch == '-' and ch2 == '>'):
                    self.reset(mark)
                    return 1
                else:
                    self.reset(mark)
                    return 0
        else:
            return 1

    def peekChar(self, cnt=1):
        if self.hasMoreInput():
            return self.current.stream[self.current.cursor:self.current.cursor+cnt]
        raise EOFError

    def skipSpaces(self):
        i = 0
        while self.isSpace():
            self.nextChar()
            i += 1
        return i

    def getChars(self, start, stop):
        oldcurr = self.Mark()
        self.reset(start)
        chars = self.current.stream[start.cursor:stop.cursor]
        self.reset(oldcurr)
        return chars

    def hasMoreInput(self):
        if self.current.cursor >= len(self.current.stream):
            while self.popFile():
                if self.current.cursor < len(self.current.stream) :
                    return 1
            return 0
        return 1

    def nextContent(self):
        """Find next < char."""
        cur_cursor = self.current.cursor
        self.current.cursor += 1
        pt = self.current.stream.find('<', self.current.cursor)
        if pt == -1:
            self.current.cursor = len(self.current.stream)
        else:
            self.current.cursor = pt
        return self.current.stream[cur_cursor:self.current.cursor]

    def parseTagAttributes(self):
        """Parse the attributes at the beginning of a tag."""
        values = {}
        while 1:
            self.skipSpaces()
            ch = self.peekChar()
            if ch == '>':
                return values
            if ch == '-':
                mark = self.Mark()
                self.nextChar()
                try:
                    if self.nextChar() == '-' and self.nextChar() == '>':
                        return values
                finally:
                    self.reset(mark)
            elif ch == '%':
                mark = self.Mark()
                self.nextChar()
                try:
                    ts = self.peekChar()
                    if ts == '>':
                        self.reset(mark)
                        return values
                finally:
                    self.reset(mark)
            if ch is None:
                break
            self.parseAttributeValue(values)
        raise ValueError, 'PSP Error - unterminated attribute'

    def parseAttributeValue(self, valuedict):
        self.skipSpaces()
        name = self.parseToken(0)
        self.skipSpaces()
        if self.peekChar() != '=':
            raise ValueError, 'PSP Error - no attribute value'
        self.nextChar()
        self.skipSpaces()
        value = self.parseToken(1)
        self.skipSpaces()
        valuedict[name] = value

    def parseToken(self, quoted):
        # This may not be quite right:
        buffer = []
        self.skipSpaces()
        ch = self.peekChar()
        if quoted:
            if ch == '\"' or ch == "\'":
                endquote = ch
                ch = self.nextChar()
                ch = self.peekChar()
                while ch is not None and ch != endquote:
                    ch = self.nextChar()
                    if ch == '\\':
                        ch = self.nextChar()
                    buffer.append(ch)
                    ch = self.peekChar()
                if ch is None:
                    raise ValueError, 'PSP Error - unterminated attribute value'
                self.nextChar()
        else:
            if not self.isDelimiter():
                while not self.isDelimiter():
                    ch = self.nextChar()
                    if ch == '\\':
                        ch = self.peekChar()
                        if ch == '\"' or ch == "'" or ch == '>' or ch == '%':
                            ch = self.nextChar()
                    buffer.append(ch)
        return ''.join(buffer)