import json, re
from markupsafe import Markup
#from jinja2 import Markup
from werkzeug.exceptions import BadRequest
from importlib import import_module

class DynamicSnippetLibrary:

    params_for = None

    def __init__(self, root, path,
            orig_la=None,
            requested_la=None,
            found_la=None,
            available_la=None,
            passed_args={},
            passed_data={}
        ):
        self.orig_la = orig_la
        self.requested_la = requested_la
        self.found_la = found_la
        if available_la is None:
            self.language_versions_available = []
        else:
            self.language_versions_available = available_la
        self._root = root + '{LA}'
        self.path = path
        self.params = (passed_args, passed_data, {})
        
    def change_root(self, new_root, strip=None):
        m = re.match(r"\w+:", new_root)
        mla = '{LA}' in new_root
        if m and not mla:
            new_root = new_root + '/{LA}'
        if strip is None:
            strip = new_root
        if strip and self.path.startswith(strip):
            self.path = self.path[ len(strip) : ]
        self._root = new_root if m else self._root + '/' + new_root

        return '<!-- Root: ' + self._root + '; orig_la=' + self.orig_la + ' -->'

    def root(self, lang=None):
        if lang is None:
            lang = self.orig_la
        if not lang:
            return re.sub(r'\{LA\}/?', '', self._root)
        else:
            return self._root.replace('{LA}', lang)

    def i18n(self, **langstr):
        for lang in (self.requested_la, self.found_la, 'en', 'de'):
            if lang in langstr:
                return langstr[lang]
        else:
            return '???' + lang + '???'

    from .snippets.marginews import marginews
    from .snippets.img import img
    from .snippets.email import email
    from .snippets.up import up
    from .snippets.snippet import snippet

    # {% set ffg, success = DSL.get_form("mailform", ...) %}
    # ...
    # {{ ffg(name="subject") }} 
    def get_form(self, module, **initargs):
        mod = import_module(re.sub(r"^\.*", "..forms.", module), __name__)
        hp = mod.init(self.params[-1],initargs.pop("altfields",{}),initargs.pop("defaults",{}),**initargs)
        is_sent = self.params[-1].pop('send',False)

        if is_sent:
            success = hp.validate_params(self.params[-1])
            if success is True:
                mod.process(hp)
                error = False
        else:
            success = None

        def form_field_generator(returntype, **kwargs):
            # Parameterwert annehmen und validieren
            field = hp.fields[kwargs["name"]]
            if returntype == 'str':
                return field.value
            elif returntype == 'html':
                if not field.is_valid:
                    error = field.error_msg
                else:
                    error = False
                return Markup(field.render(**kwargs) + (f"<span class='error'>{error}</span>" if error else ""))
            # HTML-Feld darstellen. 
            # return MarkupSafe(...)
        return form_field_generator, success
        
    def virtuelleAusst(self): # Das ist doch ein Autohandler, oder?
        pass

    def flatten_meta(self, meta):
        if isinstance(meta, dict):
            metad = meta
        else:
            metad = json.loads(meta)
        super_meta = metad.pop('', None)
        if super_meta is None:
            self.meta = metad
            if not len(self.language_versions_available) \
                    and isinstance(metad['title'], dict):
                self.language_versions_available = metad['title'].keys()
                metad['title'] = self.i18n(**metad['title'])
            return metad
        super_meta.update(metad)
        super_meta = self.flatten_meta(super_meta)
        if 'allow_post_data' in super_meta:
            for key in super_meta['allow_post_data']:
                if key.endswith('+'):
                    getter = self.params[1].getlist
                    key = key[:-1]
                else:
                    getter = self.params[1].get
                if key in self.params[1]:
                    self.params[2][key] = getter(key)
        if 'allow_url_params' in super_meta:
            for key in super_meta['allow_url_params']:
                if key.endswith('+'):
                    getter = self.params[0].getlist
                    key = key[:-1]
                else:
                    getter = self.params[0].get
                self.params[2].setdefault(key, getter(key))
        return super_meta