"""form renderers, responsible to layout a form to html

:organization: Logilab

:copyright: 2009 LOGILAB S.A. (Paris, FRANCE), all rights reserved.

:contact: http://www.logilab.fr/ -- mailto:contact@logilab.fr

"""

__docformat__ = "restructuredtext en"

from logilab.common import dictattr

from logilab.mtconverter import html_escape

from simplejson import dumps

from cubicweb.common import tags

from cubicweb.web import eid_param

from cubicweb.web import formwidgets as fwdgs

from cubicweb.web.widgets import checkbox

class FormRenderer(object):

    """basic renderer displaying fields in a two columns table label | value

    +--------------+--------------+

    | field1 label | field1 input |

    +--------------+--------------+

    | field1 label | field2 input |

    +--------------+--------------+

    +---------+

    | buttons |

    +---------+

    """

    display_fields = None # None -> all fields

    display_label = True

    display_help = True

    display_progress_div = True

    button_bar_class = u'formButtonBar'

    def __init__(self, **kwargs):

        if self._set_options(kwargs):

            raise ValueError('unconsumed arguments %s' % kwargs)

    def _set_options(self, kwargs):

        for key in ('display_fields', 'display_label', 'display_help',

                    'display_progress_div', 'button_bar_class'):

            try:

                setattr(self, key, kwargs.pop(key))

            except KeyError:

                continue

        return kwargs

    # renderer interface ######################################################

    def render(self, form, values):

        self._set_options(values)

        form.add_media()

        data = []

        w = data.append

        w(self.open_form(form, values))

        if self.display_progress_div:

            w(u'<div id="progress">%s</div>' % form.req._('validating...'))

        w(u'<fieldset>')

        w(tags.input(type=u'hidden', name=u'__form_id',

                     value=values.get('formvid', form.id)))

        if form.redirect_path:

            w(tags.input(type='hidden', name='__redirectpath', value=form.redirect_path))

        self.render_fields(w, form, values)

        self.render_buttons(w, form)

        w(u'</fieldset>')

        w(u'</form>')

        errormsg = self.error_message(form)

        if errormsg:

            data.insert(0, errormsg)          

        return '\n'.join(data)

    def render_label(self, form, field):

        label = form.req._(field.label)

        attrs = {'for': form.context[field]['id']}

        if field.required:

            attrs['class'] = 'required'

        return tags.label(label, **attrs)

    def render_help(self, form, field):

        help = [ u'<br/>' ]

        descr = field.help

        if descr:

            help.append('<span class="helper">%s</span>' % form.req._(descr))

        example = field.example_format(form.req)

        if example:

            help.append('<span class="helper">(%s: %s)</span>'

                        % (form.req._('sample format'), example))

        return u' '.join(help)

    # specific methods (mostly to ease overriding) #############################

    def error_message(self, form):

        """return formatted error message

        This method should be called once inlined field errors has been consumed

        """

        req = form.req

        errex = req.data.get('formerrors')

        # get extra errors

        if errex is not None:

            errormsg = req._('please correct the following errors:')

            displayed = req.data['displayederrors']

            errors = sorted((field, err) for field, err in errex.errors.items()

                            if not field in displayed)

            if errors:

                if len(errors) > 1:

                    templstr = '<li>%s</li>\n' 

                else:

                    templstr = ' %s\n'

                for field, err in errors:

                    if field is None:

                        errormsg += templstr % err

                    else:

                        errormsg += templstr % '%s: %s' % (req._(field), err)

                if len(errors) > 1:

                    errormsg = '<ul>%s</ul>' % errormsg

            return u'<div class="errorMessage">%s</div>' % errormsg

        return u''

    def open_form(self, form, values):

        if form.form_needs_multipart:

            enctype = 'multipart/form-data'

        else:

            enctype = 'application/x-www-form-urlencoded'

        if form.action is None:

            action = form.req.build_url('edit')

        else:

            action = form.action

        tag = ('<form action="%s" method="post" enctype="%s"' % (

            html_escape(action or '#'), enctype))

        if form.domid:

            tag += ' id="%s"' % form.domid

        if form.onsubmit:

            tag += ' onsubmit="%s"' % html_escape(form.onsubmit % dictattr(form))

        if form.cssstyle:

            tag += ' style="%s"' % html_escape(form.cssstyle)

        if form.cssclass:

            tag += ' class="%s"' % html_escape(form.cssclass)

        if form.cwtarget:

            tag += ' cubicweb:target="%s"' % html_escape(form.cwtarget)

        return tag + '>'

    def display_field(self, form, field):

        return (self.display_fields is None

                or field.name in self.display_fields

                or field.name in form.internal_fields)

    def render_fields(self, w, form, values):

        form.form_build_context(values)

        fields = self._render_hidden_fields(w, form)

        if fields:

            self._render_fields(fields, w, form)

        self.render_child_forms(w, form, values)

    def render_child_forms(self, w, form, values):

        # render 

        for childform in getattr(form, 'forms', []):

            self.render_fields(w, childform, values)

    def _render_hidden_fields(self, w, form):

        fields = form.fields[:]

        for field in form.fields:

            if not self.display_field(form, field):

                fields.remove(field)

            elif not field.is_visible():

                w(field.render(form, self))

                fields.remove(field)

        return fields

    def _render_fields(self, fields, w, form):

        w(u'<table class="attributeForm">')

        for field in fields:

            w(u'<tr>')

            if self.display_label:

                w(u'<th class="labelCol">%s</th>' % self.render_label(form, field))

            error = form.form_field_error(field)

            if error:

                w(u'<td class="error">')

                w(error)

            else:

                w(u'<td>')

            w(field.render(form, self))

            if self.display_help:

                w(self.render_help(form, field))

            w(u'</td></tr>')

        w(u'</table>')

    def render_buttons(self, w, form):

        w(u'<table class="%s">\n<tr>\n' % self.button_bar_class)

        for button in form.form_buttons:

            w(u'<td>%s</td>\n' % button.render(form))

        w(u'</tr></table>')

class HTableFormRenderer(FormRenderer):

    """display fields horizontally in a table

    +--------------+--------------+---------+

    | field1 label | field2 label |         |

    +--------------+--------------+---------+

    | field1 input | field2 input | buttons

    +--------------+--------------+---------+ 

    """

    display_help = False

    def _render_fields(self, fields, w, form):

        w(u'<table border="0">')

        w(u'<tr>')

        for field in fields:            

            if self.display_label:

                w(u'<th class="labelCol">%s</th>' % self.render_label(form, field))

            if self.display_help:

                w(self.render_help(form, field))

        # empty slot for buttons

        w(u'<th class="labelCol">&nbsp;</th>')

        w(u'</tr>')

        w(u'<tr>')

        for field in fields:                        

            error = form.form_field_error(field)

            if error:

                w(u'<td class="error" style="width:100%;">')

                w(error)

            else:

                w(u'<td style="width:100%;">')

            w(field.render(form, self))

            w(u'</td>')

        w(u'<td>')

        for button in form.form_buttons:

            w(button.render(form))

        w(u'</td>')

        w(u'</tr>')

        w(u'</table>')

    def render_buttons(self, w, form):

        pass

class EntityCompositeFormRenderer(FormRenderer):

    """specific renderer for multiple entities edition form (muledit)"""

    def render_fields(self, w, form, values):

        if not form.is_subform:

            w(u'<table class="listing">')

        super(EntityCompositeFormRenderer, self).render_fields(w, form, values)

        if not form.is_subform:

            w(u'</table>')

    def _render_fields(self, fields, w, form):

        if form.is_subform:

            entity = form.edited_entity

            values = form._previous_values

            qeid = eid_param('eid', entity.eid)

            cbsetstate = "setCheckboxesState2('eid', %s, 'checked')" % html_escape(dumps(entity.eid))

            w(u'<tr class="%s">' % (entity.row % 2 and u'even' or u'odd'))

            # XXX turn this into a widget used on the eid field

            w(u'<td>%s</td>' % checkbox('eid', entity.eid, checked=qeid in values))

            for field in fields:

                error = form.form_field_error(field)

                if error:

                    w(u'<td class="error">')

                    w(error)

                else:

                    w(u'<td>')

                if isinstance(field.widget, (fwdgs.Select, fwdgs.CheckBox, fwdgs.Radio)):

                    field.widget.attrs['onchange'] = cbsetstate

                elif isinstance(field.widget, fwdgs.Input):

                    field.widget.attrs['onkeypress'] = cbsetstate

                w(u'<div>%s</div>' % field.render(form, self))

                w(u'/<td>')

        else:

            # main form, display table headers

            w(u'<tr class="header">')

            w(u'<th align="left">%s</th>'

              % tags.input(type='checkbox', title=form.req._('toggle check boxes'),

                           onclick="setCheckboxesState('eid', this.checked)"))

            for field in self.forms[0].fields:

                if self.display_field(form, field) and field.is_visible():

                    w(u'<th>%s</th>' % form.req._(field.label))

        w(u'</tr>')

class EntityFormRenderer(FormRenderer):

    """specific renderer for entity edition form (edition)"""

    def render(self, form, values):

        rendered = super(EntityFormRenderer, self).render(form, values)

        return rendered + u'</div>' # close extra div introducted by open_form

    def open_form(self, form, values):

        attrs_fs_label = ('<div class="iformTitle"><span>%s</span></div>'

                          % form.req._('main informations'))

        attrs_fs_label += '<div class="formBody">'

        return attrs_fs_label + super(EntityFormRenderer, self).open_form(form, values)

    def render_fields(self, w, form, values):

        super(EntityFormRenderer, self).render_fields(w, form, values)

        self.inline_entities_form(w, form)

        if form.edited_entity.has_eid():

            self.relations_form(w, form)

    def _render_fields(self, fields, w, form):

        if not form.edited_entity.has_eid() or form.edited_entity.has_perm('update'):

            super(EntityFormRenderer, self)._render_fields(fields, w, form)

    def render_buttons(self, w, form):

        if len(form.form_buttons) == 3:

            w("""<table width="100%%">

  <tbody>

   <tr><td align="center">

     %s

   </td><td style="align: right; width: 50%%;">

     %s

     %s

   </td></tr>

  </tbody>

 </table>""" % tuple(button.render(form) for button in form.form_buttons))

        else:

            super(EntityFormRenderer, self).render_buttons(w, form)

    def relations_form(self, w, form):

        srels_by_cat = form.srelations_by_category(('generic', 'metadata'), 'add')

        if not srels_by_cat:

            return u''

        req = form.req

        _ = req._

        label = u'%s :' % _('This %s' % form.edited_entity.e_schema).capitalize()

        eid = form.edited_entity.eid

        w(u'<fieldset class="subentity">')

        w(u'<legend class="iformTitle">%s</legend>' % label)

        w(u'<table id="relatedEntities">')

        for rschema, target, related in form.relations_table():

            # already linked entities

            if related:

                w(u'<tr><th class="labelCol">%s</th>' % rschema.display_name(req, target))

                w(u'<td>')

                w(u'<ul>')

                for viewparams in related:

                    w(u'<li class="invisible">%s<div id="span%s" class="%s">%s</div></li>'

                      % (viewparams[1], viewparams[0], viewparams[2], viewparams[3]))

                if not form.force_display and form.maxrelitems < len(related):

                    link = (u'<span class="invisible">' 

                            '[<a href="javascript: window.location.href+=\'&amp;__force_display=1\'">%s</a>]'

                            '</span>' % form.req._('view all'))

                    w(u'<li class="invisible">%s</li>' % link)

                w(u'</ul>')

                w(u'</td>')

                w(u'</tr>')

        pendings = list(form.restore_pending_inserts())

        if not pendings:

            w(u'<tr><th>&nbsp;</th><td>&nbsp;</td></tr>')

        else:

            for row in pendings:

                # soon to be linked to entities

                w(u'<tr id="tr%s">' % row[1])

                w(u'<th>%s</th>' % row[3])

                w(u'<td>')

                w(u'<a class="handle" title="%s" href="%s">[x]</a>' %

                  (_('cancel this insert'), row[2]))

                w(u'<a id="a%s" class="editionPending" href="%s">%s</a>'

                  % (row[1], row[4], html_escape(row[5])))

                w(u'</td>')

                w(u'</tr>')

        w(u'<tr id="relationSelectorRow_%s" class="separator">' % eid)

        w(u'<th class="labelCol">')

        w(u'<span>%s</span>' % _('add relation'))

        w(u'<select id="relationSelector_%s" tabindex="%s" '

          'onchange="javascript:showMatchingSelect(this.options[this.selectedIndex].value,%s);">'

          % (eid, req.next_tabindex(), html_escape(dumps(eid))))