#!/usr/bin/env python3

import collections
import datetime
import json
import random
import settings
import traceback

from kpov_draw_setup import draw_setup
import kpov_util

import pymongo
import flask
from flask import Flask, g, session, redirect, url_for, abort, render_template, flash, app, request, Response
from flask.ext.babel import Babel, gettext, ngettext
import jinja2

app = Flask(__name__)
app.config.from_object(settings)
babel = Babel(app)

@babel.localeselector
def get_locale():
    # terrible hack, should store as user preference in the DB
    if '/en/' in request.path:
        return 'en'
    if '/si/' in request.path:
        return 'sl'
    return request.accept_languages.best_match(['sl', 'en'])

dummy_task = """
def task(neznano_ime_naloge):
    print "Ta naloga ne obstaja!"
    return {'odgovor': 'neznana naloga'}

def task_check(results, params):
    raise Exception("neznana naloga?")
    return "Manjka preverjalnik naloge (neznana naloga?)"

def gen_params(user_id, meta):
    return dict()

params_meta = {'neznano_ime_naloge': {'opis':'NEZNANA NALOGA', 'w': False}}
"""


@app.before_request
def before_request():
    g.db = pymongo.MongoClient(app.config['DB_URI']).get_default_database()


@app.route('/')
@app.route('/classes/')
def index():
    student_id = flask.app.request.environ.get('REMOTE_USER', 'Nobody')
    classes = g.db.classes.find({}, {'class_id': 1, 'name': 1}).sort('class_id')
    return render_template('index.html', student_id=student_id, classes=classes)


@app.route('/classes/<class_id>/')
def class_tasks(class_id):
    student_id = flask.app.request.environ.get('REMOTE_USER', 'Nobody')
    clas = g.db.classes.find_one({'class_id': class_id})
    tasks = g.db.tasks.find({'class_id': class_id}, {'task_id': 1}).sort('task_id')
    if tasks is not None:
        task_list = [i['task_id'] for i in tasks]
    else:
        task_list = []
    return render_template('class_tasks.html', student_id=student_id, tasks=task_list, clas=clas)


def results_post(class_id, task_id, results):
    student_id = flask.app.request.environ.get('REMOTE_USER', 'Nobody')
    db = g.db
    params = db.task_params.find_one({'class_id': class_id, 'task_id': task_id, 'student_id': student_id})['params']
    if params is None:
    #    params = {}
    #else:
    #    params = params['params']
        return {'result': 0, 'hints': ['task not found'], status: 'NOT OK'} # no such task
    user_params = json.loads(flask.app.request.form['params'])
    meta = db.task_params_meta.find_one({'task_id': task_id})
    if meta is None:
        meta = {}
    else:
        meta = meta['params']
    for param_name, param_meta in meta.items():
        if param_meta.get('w', False) and param_name in user_params:
            params[param_name] = user_params[param_name]
    try:
        task_check_source = db.task_checkers.find_one({'class_id': class_id, 'task_id': task_id})['source']
        d = {}
        exec(compile(task_check_source, 'checker.py', 'exec'), globals(), d)
        res, hints = d['task_check'](collections.defaultdict(str, results), params)
    except Exception as e:
        hints = ["Checker died: " + str(e)]
        res = 0
    if (isinstance(res, int) or isinstance(res, float)) and res > 0:
        res_status = 'OK'
    else:
        res_status = 'NOT OK'
    db.results.insert({'class_id': class_id, 'task_id': task_id, 'result': res, 'hints': hints, 'status': res_status,'student_id': student_id, 'response': results, 'time': datetime.datetime.now()})
    return {'result': res, 'hints': hints, 'status': res_status}


def results_dict(class_id, task_id):
    student_id = flask.app.request.environ.get('REMOTE_USER', 'Nobody')
    db = g.db
    try:
        entry = db.results.find_one(
            {'$query': {'class_id': class_id, 'task_id': task_id, 'student_id': student_id}, # vsi uporabniki brez nastavljenega REMOTE_USER (i.e. Apache basic auth) imajo skupne rezultate, napaka?
                '$orderby': {'time': -1}},
            {'result': 1, 'status': 1, 'hints': 1, '_id': 0})
        if entry is None:
            return {'result': 'Naloga ni bila nikdar ocenjena', 'status': 'NOT OK'}
        return entry
    except Exception as e:
        return {'Error': str(e)}


@app.route('/tasks/<class_id>/<task_id>/results.json', methods=['GET', 'POST'])
def results_json(class_id, task_id):
    if flask.app.request.method == 'POST':
        return json.dumps(results_post(class_id, task_id,
                                       json.loads(flask.app.request.form['results'])))
    return json.dumps(results_dict(class_id, task_id))


@app.route('/tasks/<class_id>/<task_id>/<lang>/results.html')
def results_html(class_id, task_id, lang):
    return render_template('results.html', results=results_dict(class_id, task_id))


@app.route('/tasks/<class_id>/<task_id>/<lang>/setup.<ending>', methods=['GET'])
def setup_svg(class_id, task_id, lang, ending):
    db = g.db
    fmt, mimetype = {
        'svg':('svg', 'image/svg+xml'),
        'png':('png', 'image/png'),
    }[ending]
    networks = list(db.networks.find({'class_id': class_id, 'task_id': task_id}))
    computers = list(db.computers_meta.find({'class_id': class_id, 'task_id': task_id}))
    return Response(draw_setup(computers, networks, format=fmt,
                          icon_path=app.config['STATIC_DIR']),
                    mimetype=mimetype)


def public_meta(db, class_id, task_id):
    shown = {}
    try:
        meta = db.task_params_meta.find_one({'class_id': class_id, 'task_id': task_id})['params']
        for k, v in meta.items():
            try:
                if v['public']:
                    shown[k] = v
            except Exception:
                pass
    except Exception:
        shown = dummy_meta
    return shown


@app.route('/tasks/<class_id>/<task_id>/task.py')
def task_source(class_id, task_id):
    db = g.db
    try:
        task_str = db.tasks.find_one({'class_id': class_id, 'task_id': task_id})['source']
    except Exception:
        return dummy_task
    return task_str


@app.route('/tasks/<class_id>/<task_id>/task.html')
def task_html(class_id, task_id):
    return render_template('task.html', task=task_source(class_id, task_id))


def get_params(class_id, task_id, student_id, db):
    try:
        meta = db.task_params_meta.find_one({'class_id': class_id, 'task_id': task_id})['params']
    except Exception:
        return {'mama': 'ZAKVAJ?'}, {'mama': {'public': True}}
    params = db.task_params.find_one({'class_id': class_id, 'task_id': task_id, 'student_id': student_id})
    if params is None:
        try:
            gen_params_source = db.gen_params.find_one({'class_id': class_id, 'task_id': task_id})['source']
            gen_params_code = compile(gen_params_source, 'generator.py', 'exec')
            d = {}
            exec(gen_params_code, globals(), d)
            params = d['gen_params'](student_id, meta)
            db.task_params.update({'class_id': class_id, 'task_id': task_id, 'student_id': student_id},
                {'$set': {'params': params}}, upsert=True)
            params = d['gen_params'](student_id, meta) # TODO this is repeated, is it necessary?
            for computer in db.computers_meta.find({'class_id': class_id, 'task_id': task_id}):
                try:
                    name = computer.pop('name')
                    del computer['_id']
                    del computer['task_id']
                except Exception:
                    pass
                db.student_computers.update({'class_id': class_id, 'task_id': task_id, 'student_id': student_id, 'name': name},
                    {'$set': computer}, upsert=True)
        except Exception as e:
            meta = {'crash': {'public': True}}
            params = {'crash': "Parameter creator crashed or missing:\n{}".format(
                traceback.format_exc())}
    else:
        params = params['params']
    return params, meta


@app.route('/tasks/<class_id>/<task_id>/')
def task_lang_redirect(class_id, task_id):
    return redirect(url_for('task_greeting', class_id=class_id, task_id=task_id, lang=app.config['DEFAULT_LANG']))


@app.route('/tasks/<class_id>/<task_id>/<lang>/howto/')
def task_howto(class_id, task_id, lang):
    db = g.db
    return db.howtos.find_one({'class_id': class_id, 'task_id': task_id, 'lang': lang}).get('text', '')


@app.route('/tasks/<class_id>/<task_id>/<lang>/images/<fname>')
def task_image(class_id, task_id, lang, fname):
    db = g.db
    return db.howto_images.find_one({'class_id': class_id, 'task_id': task_id, 'fname': fname}).get('data', '')


@app.route('/tasks/<class_id>/<task_id>/<lang>/')
def task_greeting(class_id, task_id, lang):
    student_id = flask.app.request.environ.get('REMOTE_USER', 'Nobody')
    db = g.db
    # generate the parameters as soon as the student visits
    params, meta = get_params(class_id, task_id, student_id, db)
    instr_ok = True
    try:
        instructions = db.task_instructions.find_one({'class_id': class_id, 'task_id': task_id})
        instructions = instructions.get(lang, instructions[app.config['DEFAULT_LANG']])
    except Exception:
        try:
            instructions = list(instructions.values())[0]
        except Exception as e:
            instructions = str(e)
            instr_ok = False
    if instr_ok:
        try:
            public_params = {}
            for k, v in meta.items():
                if v.get('public', False):
                    public_params[k] = params.get(k, "???")
        except Exception as e:
            instructions = str(e)
    computer_list = list(db.student_computers.find({'class_id': class_id, 'task_id': task_id, 'student_id': student_id}))
    backing_images = set()
    for computer in computer_list:
        for disk_url in computer.get('disk_urls', []):
            backing_images |= set(disk_url['backing'])
    if request.args.get('narediStack', 'false') == 'true':
      #db.student_tasks.update({'task_id': task_id, 'student_id': student_id}, {'$set': {'create_openstack': True}}, upsert = True)
        openstackCreated = False # Spremeni na True, ko odkomentiras zgornjo vrstico.
    else:
        if db.student_tasks.find({'class_id': class_id, 'task_id': task_id, 'student_id': student_id, 'openstack_created': True}).count() > 0:
            openstackCreated = True
        elif db.student_tasks.find({'class_id': class_id, 'task_id': task_id, 'student_id': student_id, 'create_openstack': True}).count() > 0:
            openstackCreated = True
        else:
            openstackCreated = False
    return render_template('task_greeting.html',
        disk_base_url='/'.join([app.config['STUDENT_DISK_URL'], student_id, class_id, task_id, '']),
        class_id=class_id,
        task_id=task_id,
        computers=computer_list,
        backing_images=sorted(backing_images),
        lang='sl' if lang == 'si' else lang, # TODO s/si/sl in all tasks (and maybe elsewhere)
        openstack=openstackCreated,
        instructions=jinja2.Template(instructions),
        **public_params,
    )


@app.route('/tasks/<class_id>/<task_id>/params.json', methods=['GET', 'POST'])
def params_json(class_id, task_id):
    student_id = flask.app.request.environ.get('REMOTE_USER', 'Nobody')
    db = g.db
    params, meta = get_params(class_id, task_id, student_id, db)
    shown_params = {}
    if flask.app.request.method == 'POST':
        try:
            new_params = json.loads(flask.app.request.form['params'])
        except Exception:
            new_params = {}
        for name in params.items():
            if meta.get(name, {'w': False}).get('w', False) and k in new_params:
                params[name] = new_params[name]
            if meta.get(name, {'public': False})['public']:
                shown_params[name] = params[name]
        db.task_params.update({'class_id': class_id, 'task_id': task_id, 'student_id': student_id}, {'$set': {'params': params}})
    else:
        for name, param in params.items():
            if meta.get(name, {'public': False})['public']:
                shown_params[name] = param
    return json.dumps(shown_params)


@app.route('/tasks/<class_id>/<task_id>/<lang>/params.html', methods=['GET', 'POST'])
def params_html(class_id, task_id, lang):
    student_id = flask.app.request.environ.get('REMOTE_USER', 'Nobody')
    db = g.db
    params, meta = get_params(class_id, task_id, student_id, db)
    shown_params = {}
    for name, meta_param in meta.items():
        if meta_param.get('public', False):
            shown_params[name] = params.get(name, '')
    if flask.app.request.method == 'POST':
        form = flask.app.request.form
        new_params = {}
        for k, v in meta.items():
            if v.get('w', False):
                params[k] = flask.app.request.form[k]
            if v.get('public', False):
                shown_params[name] = params.get(name, '')
        db.task_params.update({'class_id': class_id, 'task_id': task_id, 'student_id': student_id}, {'$set': {'params': params}})
    return render_template('params.html', params=shown_params, params_meta=meta)


@app.route('/tasks/<class_id>/<task_id>/params_meta.json')
def params_meta(class_id, task_id):
   db = g.db
   return json.dumps(public_meta(db, class_id, task_id))


@app.route('/static/<path:filename>')
def send_foo(filename):
    return send_from_directory(app.config.STATIC_FILES, filename)


if __name__ == '__main__':
    app.run(host='0.0.0.0')