#!/usr/bin/python

#

# Xhtml.output -- This module encapsulates XHTML output code needed by

# web applications.

#

# Copyright (C) 2009, 2010, 2011 The CentOS Project

#

# This program is free software; you can redistribute it and/or modify

# it under the terms of the GNU General Public License as published by

# the Free Software Foundation; either version 2 of the License, or (at

# your option) any later version.

#

# This program is distributed in the hope that it will be useful, but

# WITHOUT ANY WARRANTY; without even the implied warranty of

# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

# General Public License for more details.

#

# You should have received a copy of the GNU General Public License

# along with this program; if not, write to the Free Software

# Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

#

# ----------------------------------------------------------------------

# $Id$

# ----------------------------------------------------------------------

import os

import cgi

import cgitb; cgitb.enable()

from datetime import date

qs = cgi.parse_qs(os.environ['QUERY_STRING'])

now = date.today()

def tag(name, attrs, indent=[8,1], content="", has_child=0):

    """Returns XHTML tag definition.

    Arguments:

    name: The XHTML tag's name. Notice that this function doesn't

        verify nor validate the XHTML tags you provide. It is up to

        you write them correctly considering the XHTML standard

        definition.

    attrs: The XHTML tag's attribute. Notice that this function

        doesn't verify the attributes assignation to tags. You need to

        know what attributes are considered valid to the tag you are

        creating in order to build a well-formed XHTML document. Such

        verification can be achived inside firefox browser through the

        `firebug' plugin.

    indent: The XHTML tag's indentation (Optional). This argument is a

        list of two numerical values. The first value in the list

        represents the amount of horizontal spaces between the

        beginning of line and the opening tag.  The second value in

        the list represents the amount of vertical spaces (new lines)

        between tags.

    content: The XHTML tag's content (Optional). This argument

        provides the information the tag encloses. When this argument

        is empty, tag is rendered without content.

    has_child: The XHTML tag has a child? (Optional). This argument is

        specifies whether a tag has another tag inside (1) or not (0).

        When a tag has not a child tag, indentation is applied between

        the tag content and the closing tag provoking an unecessary

        spaces to be shown. Such kind of problems are prevented by

        setting this option to `0'. On the other hand, when a tag has

        a child tag inside, using the value `1' will keep the closing

        tag indentation aligned with the opening one.

    This function encapsulates the construction of XHTML tags.  Use

    this function wherever you need to create XHTML tags. It helps to

    standardize tag constructions and their final output and, this

    way, produce consistent XHTML documents.

    """

    if indent[0] > 0:

        h_indent = ' '*indent[0]

    else:

        h_indent = ''

    if indent[1] > 0: 

        v_indent = "\n"*indent[1]

    else:

        v_indent = ''

    output = v_indent + h_indent + '<' + str(name)

    if len(attrs) > 0:

        attr_names = attrs.keys()

        attr_names.sort()

        for attr_name in attr_names:

            output += ' ' + str(attr_name) + '="' + str(attrs[attr_name]) + '"'

    if content == '':

        output += ' />'

    else:

        output += '>'

        output += str(content)

        if has_child == 1:

            output += h_indent + '</' + str(name) + '>'

        else:

            output += '</' + str(name) + '>'

    output += v_indent

    return output

def page_preamble():

    """Return XHTML code of page preamble.

    The page preamble sets the document type definition required by

    the XHTML standard.

    """

    output = '' + "\n"

    output += '

    output += ' '*4 + 'PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"' + "\n"

    output += ' '*4 + '"http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">' + "\n"

    return output

def page_logo():

    """Returns XHTML code of page logo.

    The page logo is displayed on the top-left corner of the page. We

    use this area to show The CentOS Logo, the main visual

    representation of The CentOS Project. In order to print the page

    logo correctly, the image related must be 78 pixels of height.

    """

    attrs = []

    attrs.append({'id': 'logo'})

    attrs.append({'title': 'Community Enterprise Operating System', 'href': '/centos-web/'})

    attrs.append({'src': '/centos-web-pub/Images/centos-logo.png', 'alt': 'CentOS'})

    return tag('div', attrs[0], [8,1], tag('a', attrs[1], [12,1], tag('img', attrs[2], [0,0], '', 0), 0), 1)

def page_ads_google():

    """Returns XHTML code of Google advertisement (468x60 pixels).

    """

    output = """

            <script type="text/javascript">

                google_ad_client = "pub-6973128787810819";

                google_ad_width = 468;

                google_ad_height = 60;

                google_ad_format = "468x60_as";

                google_ad_type = "text_image";

                google_ad_channel = "";

                google_color_border = "204c8d";

                google_color_bg = "345c97";

                google_color_link = "0000FF";

                google_color_text = "FFFFFF";

                google_color_url = "008000";

                //-->

            </script>

                src="http://pagead2.googlesyndication.com/pagead/show_ads.js">

            </script>

    """

    return output

def page_navibar_top():

    """Returns XHTML code of top-level navigation bar. 

    The top-level navigation bar organizes links to the web

    application The CentOS Project makes use of. Links in the

    top-level navigation bar remain always visible, no matter what web

    application you be visiting.

    Notice that web application differe one another and is not

    convenient to point them all to this definition. Instead, a

    specific definition for each web application will be created

    (based on this definition) in order for them to give the

    impression of being connected. In this process, the top-level

    navigation bar is adapted to each web application characteristics

    and the related tab is set as current.

    """

    names = []

    attrs = []

    names.append('Home')

    attrs.append({'accesskey': '1', 'title': 'The CentOS Project (Alt+Shift+1)', 'href': '/centos-web/'})

    names.append('Wiki')

    attrs.append({'accesskey': '2', 'title': 'The CentOS Wiki (Alt+Shift+2)', 'href': '/centos-web/?app=wiki'})

    names.append('Lists')

    attrs.append({'accesskey': '3', 'title': 'The CentOS Lists (Alt+Shift+3)', 'href': '/centos-web/?app=lists'})

    names.append('Forums')

    attrs.append({'accesskey': '4', 'title': 'The CentOS Forums (Alt+Shift+4)', 'href': '/centos-web/?app=forums'})

    names.append('Projects')

    attrs.append({'accesskey': '5', 'title': 'The CentOS Projects (Alt+Shift+5)', 'href': '/centos-web/?app=projects'})

    names.append('Bugs')

    attrs.append({'accesskey': '6', 'title': 'The CentOS Bugs (Alt+Shift+6)', 'href': '/centos-web/?app=bugs'})

    names.append('Docs')

    attrs.append({'accesskey': '7', 'title': 'The CentOS Documentation (Alt+Shift+7)', 'href': '/centos-web/?app=docs'})

    names.append('Downloads')

    attrs.append({'accesskey': '8', 'title': 'The CentOS Downloads (Alt+Shift+8)', 'href': '/centos-web/?app=downloads'})

    names.append('Sponsors')

    attrs.append({'accesskey': '9', 'title': 'The CentOS Downloads (Alt+Shift+9)', 'href': '/centos-web/?app=sponsors'})

    if 'app' in qs:

        focus = qs['app'][0]

    else:

        focus = names[0]

    output = page_navibar_tabs(names, attrs, focus)

    output += page_line({'class': 'page-line white'}, [8,1])

    return output

def page_navibar_tabs(names, attrs, focus="Home"):

    """Returns navigation tabs.

    Arguments:

    names: List of tab names.

    attrs: List of dictionaries for each tab name inside the `names'

        list. Dictionaries inside attrs argument contain the XHTML

        link attributes (e.g., accesskey, title, and href) used by tab

        names so they can be linkable once rendered.

    focus: Name of the tab marked as current. When no value is passed

        to this argument the `Home' value is used as default value.

    """

    navibar_tabs = ''

    for i in range(len(names)):

        content = tag('span', '', [0,0], str(names[i]))

        content = tag('a', attrs[i], [16,1], content)

        if str(names[i]).lower() == focus.lower():

            content = tag('span', {'class': 'current'}, [12,1], content, 1)

        else:

            content = tag('span', '', [12,1], content, 1)

        navibar_tabs += content

    return tag('div', {'class': 'tabs1'}, [8,1], navibar_tabs, 1)

def page_ads_release(image='ads-sample-728x90.png', description='Release Advertisement'):

    """Return last-release advertisement.

    The release advertisment is a 728x90 pixels image graphically

    designed to promote the last releases of The CentOS Distribution.

    This image is located on the header space, between the top-level

    links and application specific links. This image changes each time

    a new release is published from The CentOS Project and is only

    visible at home page (i.e., the first time shown when

    `http://www.centos.org/' domain is requested from a web browser).

    The place where the release advertisement is displayed on the web

    is an area of high visual impact, so images appearing therein

    should be carefully designed in consequence with it.  The

    frequency and priority of images in the rotation must be connected

    somehow with The CentOS Distribution releasing process.

    Previous to consider the release advertisement as such, it was

    reserved for sponsor advertisements. Nevertheless, sponsor

    advertisements were moved to a page to their own through a link in

    the top-level navegation bar.

    """

    attrs = []

    attrs.append({'class': 'ads-release'})

    attrs.append({'title': description, 'href': ''})

    attrs.append({'src': '/centos-web-pub/Images/' + image, 'alt': description})

    output = tag('div', attrs[0], [8,1], tag('a', attrs[1], [12,1], tag('img', attrs[2], [0,0], '', 0), 0), 1)

    return output

def page_userlinks(names=['Login'], attrs=[{'href': '/centos-web/?p=login'}]):

    """Returns user links.

    Arguments:

    names: List of links you want to have.

    attrs: List of dictionaries with link attributes. In order for

        links to be built correctly, both names and attrs lists must

        coincide their indexes.

    The user links are specific to each web application. They are

    shown in the right-top corner of the application navigation bar,

    just over the application navigation tabs.

    """

    userlinks = ''

    for i in range(len(names)):

        content = tag('a', attrs[i], [20,1], str(names[i]), 0)

        if i == len(names) - 1:

            content = tag('span', {'class': 'last'}, [16,1], content, 1)

        else:

            content = tag('span', '', [16,1], content, 1)

        userlinks += content 

    userlinks = tag('div', {'class': 'user'}, [12,1], userlinks, 1)

    return tag('div', {'class': 'links'}, [8,1], userlinks, 1)

def page_navibar_app(names=['Welcome'], attrs=[{'href':'/centos-web/?p=welcome'}]):

    """Returns application's navigation bar."""

    if 'p' in qs:

        focus = qs['p'][0]

    else:

        focus = names[0]

    navibar_app = page_navibar_tabs(names, attrs, focus)

    navibar_app += page_line({'class': 'page-line white'}, [8,1])

    return navibar_app

def page_breadcrumbs():

    """Returns page breadcrumbs.

    The page breadcrumbs record the last pages visited inside the

    current web application.

    """

    links = ''

    names = []

    attrs = []

    names.append('Pagination')

    attrs.append({'href': ''})

    names.append('Lists')

    attrs.append({'href': ''})

    names.append('Headings')

    attrs.append({'href': ''})

    names.append('Links')

    attrs.append({'href': ''})

    for i in range(len(names)):

        if i == len(names) - 1:

            content = tag('span', {'class':'last'}, [16,1], tag('a', attrs[i], [20, 1], names[i]), 1)

        else:

            content = tag('span', '', [16,1], tag('a', attrs[i], [20, 1], names[i], 0), 1)

        links = links + content

    return tag('div', {'class': 'trail'}, [12,1], links, 1)

def page_line(attrs={'class': 'page-line'}, indent=[8,1]):

    """Returns a division line."""

    page_line = tag('hr', {'style': 'display:none;'}, [0,0])

    page_line = tag('div', attrs, indent, page_line)

    return page_line

def page_title(title='The CentOS Project'):

    """Returns page title."""

    title = 'The CentOS Project'

    if 'app' in qs.keys():

        title += ' :: ' + qs['app'][0].capitalize()

    return title

def page_language(language='en'):

    """Returns page language."""

    return language

def page_keywords(keywords='centos, project, community, enterprise, operating system'):

    """Returns page keywords."""

    return keywords

def page_description(description="Community Enterprise Operating    tem"):

    """Returns page description."""

    return description

def page_copyright(copyright_year=now.strftime("%Y"), 

                   copyright_holder='The CentOS Project. All rights reserved.'):

    """Returns page copyright."""

    return copyright_year + ' ' + copyright_holder 

def page_license():

    """Retruns link to page license."""

    license = 'Creative Commons Attribution-Share Alike 3.0 Unported License.'

    license = tag('a', {'href': 'http://creativecommons.org/licenses/by-sa/3.0/'}, [0,0], license)

    return license

def page_metadata():

    """Returns page metadata."""

    metadata = tag('meta', {'http-equiv': 'content-type', 'content': 'text/html; charset=UTF-8'}, [4,1])

    metadata += tag('meta', {'http-equiv': 'content-style-type', 'content': 'text/css'}, [4,0])

    metadata += tag('meta', {'http-equiv': 'content-language', 'content': str(page_language())}, [4,1])

    metadata += tag('meta', {'name': 'keywords', 'content': str(page_keywords())}, [4,0])

    metadata += tag('meta', {'name': 'description', 'content': str(page_description())}, [4,1])

    metadata += tag('meta', {'name': 'copyright', 'content': 'Copyright © ' + str(page_copyright())}, [4,0])

    metadata += tag('title', '', [4,1], page_title())

    metadata += tag('link', {'href': '/centos-web-pub/stylesheet.css','rel': 'stylesheet', 'type': 'text/css'}, [4,1])

    metadata += tag('link', {'href': '/centos-web-pub/Images/centos-fav.png', 'rel': 'shortcut icon', 'type': 'image/png'}, [4,0])

    return tag('head', '', [0,1], metadata)

def page_credits():

    """Returns page credits."""

    copyright = tag('p', {'class': 'copyright'}, [12,1], 'Copyright © ' + str(page_copyright()))

    license = tag('p', {'class': 'license'}, [12,1], 'This website is licensed under a ' + str(page_license()))

    credits = tag('img', {'src': '/centos-web-pub/Images/top.png', 'alt': 'Top'}, [0,0])

    credits = tag('a', {'title': 'Top', 'href': '#top'}, [16,1], credits)

    credits = tag('div', {'class': 'top'}, [12,1], credits, 1)

    credits = str(credits) + str(copyright) + str(license) 

    credits = tag('div', {'class': 'credits'}, [8,1], credits, 1)

    return credits

def page_content():

    """Returns page content."""

    content = tag('h1', {'class': 'title'}, [12, 1], page_title())

    content += tag('p', '', [12, 1], 'No content found for this page.')

    return content

def page():

    """Returns page final output."""

    page_header = page_logo()

    page_header += page_ads_google()

    page_header += page_navibar_top()

    if not 'app' in qs:

        page_header += page_ads_release()

        page_header += page_userlinks()

        page_header += page_navibar_app()

    page_header = tag('div', {'id': 'page-header'}, [4,1], page_header, 1)

    page_body = page_content() + page_line(indent=[12,1])

    page_body = tag('div', {'id':'content'}, [8,1], page_body, 1)

    page_body = tag('div', {'id':'page-body'}, [4,1], page_body, 1)

    page_footer = page_line(indent=[4,1])

    page_footer += tag('div', {'id': 'page-footer'}, [4,1], page_credits(), 1)

    top = tag('a', {'name':'top'}, [0,1], '')

    wrap = tag('div', {'id': 'wrap'}, [0,1], page_header + page_body + page_footer)

    body = tag('body', '', [0,1], top + wrap)

    html = page_preamble()

    html += tag('html', {'xmlns': 'http://www.w3.org/1999/xhtml', 'dir': 'ltr', 

                         'lang': str(page_language()), 'xml:lang':

                         str(page_language())}, [0,1], page_metadata() +  body)

    return html

def main():

    """The Xhtml code of a complete page."""

    print 'Content-type: text/html' + "\n"

    print page()