#!/usr/bin/env python
#
# Module for handling SCons documentation processing.
#

__doc__ = """
This module parses home-brew XML files that document various things
in SCons.  Right now, it handles Builders, construction variables,
and Tools, but we expect it to get extended in the future.

In general, you can use any DocBook tag in the input, and this module
just adds processing various home-brew tags to try to make life a
little easier.

Builder example:

    <builder name="VARIABLE">
    <summary>
    This is the summary description of an SCons Tool.
    It will get placed in the man page,
    and in the appropriate User's Guide appendix.
    The name of any builder may be interpolated
    anywhere in the document by specifying the
    &b-VARIABLE;
    element.  It need not be on a line by itself.

    Unlike normal XML, blank lines are significant in these
    descriptions and serve to separate paragraphs.
    They'll get replaced in DocBook output with appropriate tags
    to indicate a new paragraph.

    <example>
    print "this is example code, it will be offset and indented"
    </example>
    </summary>
    </builder>

Construction variable example:

    <cvar name="VARIABLE">
    <summary>
    This is the summary description of a construction variable.
    It will get placed in the man page,
    and in the appropriate User's Guide appendix.
    The name of any construction variable may be interpolated
    anywhere in the document by specifying the
    &t-VARIABLE;
    element.  It need not be on a line by itself.

    Unlike normal XML, blank lines are significant in these
    descriptions and serve to separate paragraphs.
    They'll get replaced in DocBook output with appropriate tags
    to indicate a new paragraph.

    <example>
    print "this is example code, it will be offset and indented"
    </example>
    </summary>
    </cvar>

Tool example:

    <tool name="VARIABLE">
    <summary>
    This is the summary description of an SCons Tool.
    It will get placed in the man page,
    and in the appropriate User's Guide appendix.
    The name of any tool may be interpolated
    anywhere in the document by specifying the
    &t-VARIABLE;
    element.  It need not be on a line by itself.

    Unlike normal XML, blank lines are significant in these
    descriptions and serve to separate paragraphs.
    They'll get replaced in DocBook output with appropriate tags
    to indicate a new paragraph.

    <example>
    print "this is example code, it will be offset and indented"
    </example>
    </summary>
    </tool>
"""

import os.path
import imp
import sys
import xml.sax.handler

class Item:
    def __init__(self, name):
        self.name = name
        self.sort_name = name.lower()
        if self.sort_name[0] == '_':
            self.sort_name = self.sort_name[1:]
        self.summary = []
        self.sets = None
        self.uses = None
    def cmp_name(self, name):
        if name[0] == '_':
            name = name[1:]
        return name.lower()
    def __cmp__(self, other):
        return cmp(self.sort_name, other.sort_name)

class Builder(Item):
    pass

class Tool(Item):
    def __init__(self, name):
        Item.__init__(self, name)
        self.entity = self.name.replace('+', 'X')

class ConstructionVariable(Item):
    pass

class Chunk:
    def __init__(self, tag, body=None):
        self.tag = tag
        if not body:
            body = []
        self.body = body
    def __str__(self):
        body = ''.join(self.body)
        return "<%s>%s</%s>\n" % (self.tag, body, self.tag)
    def append(self, data):
        self.body.append(data)

class Summary:
    def __init__(self):
        self.body = []
        self.collect = []
    def append(self, data):
        self.collect.append(data)
    def end_para(self):
        text = ''.join(self.collect)
        paras = text.split('\n\n')
        if paras == ['\n']:
            return
        if paras[0] == '':
            self.body.append('\n')
            paras = paras[1:]
            paras[0] = '\n' + paras[0]
        if paras[-1] == '':
            paras = paras[:-1]
            paras[-1] = paras[-1] + '\n'
            last = '\n'
        else:
            last = None
        sep = None
        for p in paras:
            c = Chunk("para", p)
            if sep:
                self.body.append(sep)
            self.body.append(c)
            sep = '\n'
        if last:
            self.body.append(last)
    def begin_chunk(self, chunk):
        self.end_para()
        self.collect = chunk
    def end_chunk(self):
        self.body.append(self.collect)
        self.collect = []

class SConsDocHandler(xml.sax.handler.ContentHandler,
                      xml.sax.handler.ErrorHandler):
    def __init__(self):
        self._start_dispatch = {}
        self._end_dispatch = {}
        keys = self.__class__.__dict__.keys()
        start_tag_method_names = filter(lambda k: k[:6] == 'start_', keys)
        end_tag_method_names = filter(lambda k: k[:4] == 'end_', keys)
        for method_name in start_tag_method_names:
            tag = method_name[6:]
            self._start_dispatch[tag] = getattr(self, method_name)
        for method_name in end_tag_method_names:
            tag = method_name[4:]
            self._end_dispatch[tag] = getattr(self, method_name)
        self.stack = []
        self.collect = []
        self.current_object = []
        self.builders = {}
        self.tools = {}
        self.cvars = {}

    def startElement(self, name, attrs):
        try:
            start_element_method = self._start_dispatch[name]
        except KeyError:
            self.characters('<%s>' % name)
        else:
            start_element_method(attrs)

    def endElement(self, name):
        try:
            end_element_method = self._end_dispatch[name]
        except KeyError:
            self.characters('</%s>' % name)
        else:
            end_element_method()

    #
    #
    def characters(self, chars):
        self.collect.append(chars)

    def begin_collecting(self, chunk):
        self.collect = chunk
    def end_collecting(self):
        self.collect = []

    def begin_chunk(self):
        pass
    def end_chunk(self):
        pass

    #
    #
    #

    def begin_xxx(self, obj):
        self.stack.append(self.current_object)
        self.current_object = obj
    def end_xxx(self):
        self.current_object = self.stack.pop()

    #
    #
    #
    def start_scons_doc(self, attrs):
        pass
    def end_scons_doc(self):
        pass

    def start_builder(self, attrs):
        name = attrs.get('name')
        try:
            builder = self.builders[name]
        except KeyError:
            builder = Builder(name)
            self.builders[name] = builder
        self.begin_xxx(builder)
    def end_builder(self):
        self.end_xxx()

    def start_tool(self, attrs):
        name = attrs.get('name')
        try:
            tool = self.tools[name]
        except KeyError:
            tool = Tool(name)
            self.tools[name] = tool
        self.begin_xxx(tool)
    def end_tool(self):
        self.end_xxx()

    def start_cvar(self, attrs):
        name = attrs.get('name')
        try:
            cvar = self.cvars[name]
        except KeyError:
            cvar = ConstructionVariable(name)
            self.cvars[name] = cvar
        self.begin_xxx(cvar)
    def end_cvar(self):
        self.end_xxx()

    def start_summary(self, attrs):
        summary = Summary()
        self.current_object.summary = summary
        self.begin_xxx(summary)
        self.begin_collecting(summary)
    def end_summary(self):
        self.current_object.end_para()
        self.end_xxx()

    def start_example(self, attrs):
        example = Chunk("programlisting")
        self.current_object.begin_chunk(example)
    def end_example(self):
        self.current_object.end_chunk()

    def start_uses(self, attrs):
        self.begin_collecting([])
    def end_uses(self):
        self.current_object.uses = ''.join(self.collect).split()
        self.current_object.uses.sort()
        self.end_collecting()

    def start_sets(self, attrs):
        self.begin_collecting([])
    def end_sets(self):
        self.current_object.sets = ''.join(self.collect).split()
        self.current_object.sets.sort()
        self.end_collecting()

    # Stuff for the ErrorHandler portion.
    def error(self, exception):
        linenum = exception._linenum - self.preamble_lines
        sys.stderr.write('%s:%d:%d: %s (error)\n' % (self.filename, linenum, exception._colnum, ''.join(exception.args)))

    def fatalError(self, exception):
        linenum = exception._linenum - self.preamble_lines
        sys.stderr.write('%s:%d:%d: %s (fatalError)\n' % (self.filename, linenum, exception._colnum, ''.join(exception.args)))

    def set_file_info(self, filename, preamble_lines):
        self.filename = filename
        self.preamble_lines = preamble_lines

# lifted from Ka-Ping Yee's way cool pydoc module.
def importfile(path):
    """Import a Python source file or compiled file given its path."""
    magic = imp.get_magic()
    file = open(path, 'r')
    if file.read(len(magic)) == magic:
        kind = imp.PY_COMPILED
    else:
        kind = imp.PY_SOURCE
    file.close()
    filename = os.path.basename(path)
    name, ext = os.path.splitext(filename)
    file = open(path, 'r')
    try:
        module = imp.load_module(name, file, path, (ext, 'r', kind))
    except ImportError, e:
        sys.stderr.write("Could not import %s: %s\n" % (path, e))
        return None
    file.close()
    return module