#######################################################################
# This file is part of Pyblosxom.
#
# Copyright (C) 2003-2011 by the Pyblosxom team.  See AUTHORS.
#
# Pyblosxom is distributed under the MIT license.  See the file
# LICENSE for distribution details.
#######################################################################

"""
This is the default blosxom renderer.  It tries to match the behavior
of the blosxom renderer.
"""

import os
import sys

from Pyblosxom import tools
from Pyblosxom.renderers.base import RendererBase


class NoSuchFlavourException(Exception):
    """
    This exception gets thrown when the flavour requested is not
    available in this blog.
    """
    pass


def get_included_flavour(taste):
    """
    Pyblosxom comes with flavours in taste.flav directories in the flavours
    subdirectory of the Pyblosxom package.  This method pulls the template
    files for the associated taste (assuming it exists) or None if it
    doesn't.

    :param taste: The name of the taste.  e.g. "html", "rss", ...

    :returns: A dict of template type to template file or None
    """
    path = __file__[:__file__.rfind(os.sep)]
    path = path[:path.rfind(os.sep)+1] + "flavours" + os.sep

    path = path + taste + ".flav"

    if os.path.isdir(path):
        template_files = os.listdir(path)
        template_d = {}
        for mem in template_files:
            name, ext = os.path.splitext(mem)
            if ext not in ["." + taste, ""] or name.startswith("."):
                continue
            template_d[name] = os.path.join(path, mem)
        return template_d

    return None


def get_flavour_from_dir(path, taste):
    """
    Tries to get the template files for the flavour of a certain
    taste (html, rss, atom10, ...) in a directory.  The files could
    be in the directory or in a taste.flav subdirectory.

    :param path: the path of the directory to look for the flavour
                 templates in

    :param taste: the flavour files to look for (e.g. html, rss, atom10, ...)

    :returns: the map of template name to template file path
    """
    template_d = {}

    # if we have a taste.flav directory, we check there
    if os.path.isdir(path + os.sep + taste + ".flav"):
        newpath = path + os.sep + taste + ".flav"
        template_files = os.listdir(newpath)
        for mem in template_files:
            name, ext = os.path.splitext(mem)
            if ext not in ["." + taste, ""]:
                continue
            template_d[name] = os.path.join(path + os.sep + taste + ".flav",
                                            mem)
        return template_d

    # now we check the directory itself for flavour templates
    template_files = os.listdir(path)
    for mem in template_files:
        if not mem.endswith("." + taste):
            continue
        template_d[os.path.splitext(mem)[0]] = path + os.sep + mem

    if template_d:
        return template_d

    return None


class BlosxomRenderer(RendererBase):
    """
    This is the default blosxom renderer.  It tries to match the behavior
    of the blosxom renderer.
    """
    def __init__(self, request, stdoutput=sys.stdout):
        RendererBase.__init__(self, request, stdoutput)
        config = request.get_configuration()
        self._request = request
        self.flavour = None

    def get_parse_vars(self):
        """Returns a dict starting with standard filters, config
        information, then data information.  This allows vars
        to override each other correctly.  For example, plugins
        should be adding to the data dict which will override
        stuff in the config dict.
        """
        parsevars = dict(tools.STANDARD_FILTERS)
        parsevars.update(self._request.config)
        parsevars.update(self._request.data)
        return parsevars

    def get_flavour(self, taste='html'):
        """
        This retrieves all the template files for a given flavour
        taste.  This will first pull the templates for the default
        flavour of this taste if there are any.  Then it looks at
        EITHER the configured datadir OR the flavourdir (if
        configured).  It'll go through directories overriding the
        template files it has already picked up descending the
        category path of the Pyblosxom request.

        For example, if the user requested the ``html`` flavour and is
        looking at an entry in the category ``dev/pyblosxom``, then
        ``get_flavour`` will:

        1. pick up the flavour files in the default html flavour
        2. start in EITHER datadir OR flavourdir (if configured)
        3. override the default html flavour files with html flavour
           files in this directory or in ``html.flav/`` subdirectory
        4. override the html flavour files it's picked up so far
           with html files in ``dev/`` or ``dev/html.flav/``
        5. override the html flavour files it's picked up so far
           with html files in ``dev/pyblosxom/`` or
           ``dev/pyblosxom/html.flav/``

        If it doesn't find any flavour files at all, then it returns
        None which indicates the flavour doesn't exist in this blog.

        :param taste: the taste to retrieve flavour files for.

        :returns: mapping of template name to template file data
        """
        data = self._request.get_data()
        config = self._request.get_configuration()
        datadir = config["datadir"]

        # if they have flavourdir set, then we look there.  otherwise
        # we look in the datadir.
        flavourdir = config.get("flavourdir", datadir)

        # first we grab the flavour files for the included flavour (if
        # we have one).
        template_d = get_included_flavour(taste)
        if not template_d:
            template_d = {}

        pathinfo = list(data["path_info"])

        # check the root of flavourdir for templates
        new_files = get_flavour_from_dir(flavourdir, taste)
        if new_files:
            template_d.update(new_files)

        # go through all the directories from the flavourdir all
        # the way up to the root_datadir.  this way template files
        # can override template files in parent directories.
        while len(pathinfo) > 0:
            flavourdir = os.path.join(flavourdir, pathinfo.pop(0))
            if os.path.isfile(flavourdir):
                break

            if not os.path.isdir(flavourdir):
                break

            new_files = get_flavour_from_dir(flavourdir, taste)
            if new_files:
                template_d.update(new_files)

        # if we still haven't found our flavour files, we raise an exception
        if not template_d:
            raise NoSuchFlavourException("Flavour '%s' does not exist." % taste)

        for k in template_d.keys():
            try:
                flav_template = open(template_d[k]).read()
                template_d[k] = flav_template
            except (OSError, IOError):
                pass

        return template_d

    def render_content(self, content):
        """
        Processes the content for the story portion of a page.

        :param content: the content to be rendered

        :returns: the content string
        """
        data = self._request.get_data()

        outputbuffer = []

        if callable(content):
            # if the content is a callable function, then we just spit out
            # whatever it returns as a string
            outputbuffer.append(content())

        elif isinstance(content, dict):
            # if the content is a dict, then we parse it as if it were an
            # entry--except it's distinctly not an EntryBase derivative
            var_dict = self.get_parse_vars()
            var_dict.update(content)

            output = tools.parse(self._request, var_dict, self.flavour['story'])
            outputbuffer.append(output)

        elif isinstance(content, list):
            if len(content) > 0:
                current_date = content[0]["date"]

                if current_date and "date_head" in self.flavour:
                    parse_vars = self.get_parse_vars()
                    parse_vars.update({"date": current_date,
                                       "yr": content[0]["yr"],
                                       "mo": content[0]["mo"],
                                       "da": content[0]["da"]})
                    outputbuffer.append(
                        self.render_template(parse_vars, "date_head"))

                for entry in content:
                    if entry["date"] and entry["date"] != current_date:
                        if "date_foot" in self.flavour:
                            parse_vars = self.get_parse_vars()
                            parse_vars.update({"date": current_date,
                                               "yr": content[0]["yr"],
                                               "mo": content[0]["mo"],
                                               "da": content[0]["da"]})

                            outputbuffer.append(
                                self.render_template(parse_vars, "date_foot"))

                        if "date_head" in self.flavour:
                            current_date = entry["date"]
                            parse_vars = self.get_parse_vars()
                            parse_vars.update({"date": current_date,
                                               "yr": content[0]["yr"],
                                               "mo": content[0]["mo"],
                                               "da": content[0]["da"]})
                            outputbuffer.append(
                                self.render_template(parse_vars, "date_head"))

                    if data['content-type'] == 'text/plain':
                        s = tools.Stripper()
                        s.feed(entry.get_data())
                        s.close()
                        p = ['  ' + line for line in s.gettext().split('\n')]
                        entry.set_data('\n'.join(p))

                    parse_vars = self.get_parse_vars()
                    parse_vars.update(entry)

                    outputbuffer.append(
                        self.render_template(parse_vars, "story", override=1))

                    args = {"entry": parse_vars, "template": ""}
                    args = self._run_callback("story_end", args)
                    outputbuffer.append(args["template"])

                if current_date and "date_foot" in self.flavour:
                    parse_vars = self.get_parse_vars()
                    parse_vars.update({"date": current_date})
                    outputbuffer.append(
                        self.render_template(parse_vars, "date_foot"))

        return outputbuffer

    renderContent = tools.deprecated_function(render_content)

    def render(self, header=True):
        """
        Figures out flavours and such and then renders the content according
        to which flavour we're using.

        :param header: whether (True) or not (False) to render the HTTP headers
        """
        # if we've already rendered, then we don't want to do so again
        if self.rendered:
            return

        data = self._request.get_data()
        config = self._request.get_configuration()

        try:
            self.flavour = self.get_flavour(data.get("flavour", "html"))

        except NoSuchFlavourException, nsfe:
            error_msg = str(nsfe)
            try:
                self.flavour = self.get_flavour("error")
            except NoSuchFlavourException:
                self.flavour = get_included_flavour("error")
                error_msg += "  And your error flavour doesn't exist, either."

            resp = self._request.getResponse()
            resp.set_status("404 Not Found")
            self._content = {"title": "HTTP 404: Flavour error",
                             "body": error_msg}

        data['content-type'] = self.flavour['content_type'].strip()
        if header:
            if self._needs_content_type and data['content-type'] != "":
                self.add_header('Content-type', '%(content-type)s' % data)

            self.show_headers()

        if self._content:
            if "head" in self.flavour:
                self.write(self.render_template(self.get_parse_vars(), "head"))
            if "story" in self.flavour:
                content = self.render_content(self._content)
                for i, mem in enumerate(content):
                    if isinstance(mem, unicode):
                        content[i] = mem.encode("utf-8")
                content = "".join(content)
                self.write(content)
            if "foot" in self.flavour:
                self.write(self.render_template(self.get_parse_vars(), "foot"))

        self.rendered = 1

    def render_template(self, entry, template_name, override=0):
        """
        Find the flavour template for template_name, run any blosxom
        callbacks, substitute entry into it and render the template.

        If the entry has a ``template_name`` property and override is
        True (this happens in the story template), then we'll use that
        template instead.

        :param entry: the entry/variable-dict to use for expanding variables

        :param template_name: template name (gets looked up in self.flavour)

        :param override: whether (True) or not (False) this template can
            be overriden with the ``template_name`` value in the entry
        """
        template = ""
        if override:
            # here we do a quick override...  if the entry has a
            # template field we use that instead of the template_name
            # argument passed in.
            actual_template_name = entry.get("template_name", template_name)
            template = self.flavour.get(actual_template_name, '')

        if not template:
            template = self.flavour.get(template_name, '')

        # we run this through the regular callbacks
        args = self._run_callback(template_name,
                                  {"entry": entry, "template": template})

        template = args["template"]

        # FIXME - the finaltext.replace(...) below causes \$ to get
        # unescaped in title and body text which is wrong.  this
        # fix alleviates that somewhat, but there are still edge
        # cases regarding function data.  need a real template
        # engine with a real parser here.
        entry = dict(args["entry"])
        for k, v in entry.items():
            if isinstance(v, basestring):
                entry[k] = v.replace(r"\$", r"\\$")

        finaltext = tools.parse(self._request, entry, template)
        return finaltext.replace(r'\$', '$')

    renderTemplate = tools.deprecated_function(render_template)

    def _run_callback(self, chain, input):
        """
        Makes calling blosxom callbacks a bit easier since they all
        have the same mechanics.  This function merely calls
        run_callback with the arguments given and a mappingfunc.

        The mappingfunc copies the ``template`` value from the output to
        the input for the next function.

        Refer to run_callback for more details.
        """
        input.update({"renderer": self})
        input.update({"request": self._request})

        return tools.run_callback(chain, input,
                                  mappingfunc=lambda x,y: x,
                                  defaultfunc=lambda x:x)

    def output_template(self, output, entry, template_name):
        """
        Deprecated.  Here for backwards compatibility.
        """
        output.append(self.render_template(entry, template_name))

    outputTemplate = tools.deprecated_function(output_template)


class Renderer(BlosxomRenderer):
    pass
