# encoding: utf-8
# vi:si:et:sw=4:sts=4:ts=4
import sys
import inspect
import os
import json
from urlparse import urlparse

from twisted.web.resource import Resource
from twisted.web.static import File
from twisted.web.util import Redirect

from version import __version__

def trim(docstring):
    if not docstring:
        return ''
    # Convert tabs to spaces (following the normal Python rules)
    # and split into a list of lines:
    lines = docstring.expandtabs().splitlines()
    # Determine minimum indentation (first line doesn't count):
    indent = sys.maxint
    for line in lines[1:]:
        stripped = line.lstrip()
        if stripped:
            indent = min(indent, len(line) - len(stripped))
    # Remove indentation (first line is special):
    trimmed = [lines[0].strip()]
    if indent < sys.maxint:
        for line in lines[1:]:
            trimmed.append(line[indent:].rstrip())
    # Strip off trailing and leading blank lines:
    while trimmed and not trimmed[-1]:
        trimmed.pop()
    while trimmed and not trimmed[0]:
        trimmed.pop(0)
    # Return a single string:
    return '\n'.join(trimmed)

def json_response(data=None, status=200, text='ok'):
    if not data:
        data = {}
    return {'status': {'code': status, 'text': text}, 'data': data}

class ApiActions(dict):
    properties = {}
    def __init__(self):

        def api(backend, site, data):
            '''
                returns list of all known api actions
                param data {
                    docs: bool
                }
                if docs is true, action properties contain docstrings
                return {
                    status: {'code': int, 'text': string},
                    data: {
                        actions: {
                            'api': {
                                cache: true,
                                doc: 'recursion'
                            },
                            'hello': {
                                cache: true,
                                ..
                            }
                            ...
                        }
                    }
                }
            '''
            docs = data.get('docs', False)
            code = data.get('code', False)
            _actions = self.keys()
            _actions.sort()
            actions = {}
            for a in _actions:
                actions[a] = self.properties[a]
                if docs:
                    actions[a]['doc'] = self.doc(a)
                if code:
                    actions[a]['code'] = self.code(a)
            response = json_response({'actions': actions})
            return response
        self.register(api)

    def doc(self, f):
        return trim(self[f].__doc__)

    def code(self, name):
        f = self[name]
        if name != 'api' and hasattr(f, 'func_closure') and f.func_closure:
            f = f.func_closure[0].cell_contents 
        info = f.func_code.co_firstlineno
        return info, trim(inspect.getsource(f))

    def register(self, method, action=None, cache=True):
        if not action:
            action = method.func_name
        self[action] = method
        self.properties[action] = {'cache': cache}

    def unregister(self, action):
        if action in self:
            del self[action]

    def render(self, backend, site, action, data):
        if action in self:
            result = self[action](backend, site, data)
        else:
            result = json_response(status=404, text='not found')
        #print result
        return json.dumps(result) 

actions = ApiActions()


class Server(Resource):

    def __init__(self, base, backend):
        self.base = base
        self.backend = backend
        Resource.__init__(self)

    def static_path(self, path):
        return os.path.join(self.base, 'static', path)

    def get_site(self, request):
        headers = request.getAllHeaders()
        #print headers
        if 'origin' in headers:
            request.headers['Access-Control-Allow-Origin'] = headers['origin']
            site = headers['origin']
        elif 'referer' in headers:
            u = urlparse(headers['referer'])
            site = u.scheme + '://' + u.hostname
        else:
            site = 'http://' + headers['host']
        return site

    def getChild(self, name, request):
        print request
        if name in ('icon.png', 'favicon.ico'):
            f = File(self.static_path('png/icon16.png'))
            f.isLeaf = True
            return f
        if request.path == '/api/':
            return self
        if request.path.endswith('.webm'):
            video = request.path
            site = self.get_site(request)
            itemId, filename = video[1:].split('/')
            path = self.backend.get_file(site, itemId, filename)
            if path:
                print itemId, filename, 'use', path
                request.headers['Access-Control-Allow-Origin'] = '*'
                f = File(path, 'video/webm')
                f.isLeaf = True
                return f
            else:
                url = site + video
                #url = 'http://padmo.local/B/240p.webm'
                print "redirect", url
                return Redirect(url)
        path = request.path
        path = path[1:]
        if not path:
            path = 'index.html'
        path = self.static_path(path)
        f = File(path)
        if not os.path.isdir(path):
            f.isLeaf = True
        return f

    def render_POST(self, request):
        print 'render_POST'
        request.headers['Server'] = 'pandoralocal/%s' % __version__
        site = self.get_site(request)
        print "POST", request.args
        if 'action' in request.args:
            if 'data' in request.args:
                data = json.loads(request.args['data'][0])
            else:
                data = {}
            action = request.args['action'][0]
            return actions.render(self.backend, site, action, data)

    def render_GET(self, request):
        print 'render_GET'
        request.headers['Server'] = 'pandoralocal/%s' % __version__
        path = self.static_path('api.html')
        f = open(path)
        data = f.read()
        f.close()
        request.headers['Content-Type'] = 'text/html'
        site = self.get_site(request)
        data = data.replace('$name', site)
        return data