from datetime import datetime
import json
from pathlib import Path

from flask import Flask, request, render_template

from form_content import FormContent
from utils import get_data_stats

app = Flask(__name__)
save_path = Path('data.json')
data_cache = { entry['email']: entry for entry in json.loads(save_path.read_text()) }\
    if save_path.exists() else {}
stats_cache = get_data_stats(data_cache)

MAX_FILE_SIZE = 1_000_000
MAX_REQUEST_LENGTH = 1_000


@app.route('/')
def form():
    return render_template('form.html',
                           times=FormContent.times,
                           topics=FormContent.topics,
                           background=FormContent.background,
                           languages=FormContent.languages)


@app.route('/submit', methods=['POST'])
def submit():
    if save_path.exists() and save_path.stat().st_size > MAX_FILE_SIZE:
        return { 'error': 'Database full.' }, 500
    if len(request.data) > MAX_REQUEST_LENGTH:
        return { 'error': 'Request too long.' }, 400

    data = request.get_json()

    if set(data) != FormContent.all_keys:
        return { 'error': 'Invalid request format.' }, 400

    data['date_submitted'] = datetime.strftime(datetime.now(), '%Y/%m/%d, %H:%M:%S')

    data_cache[data['email']] = data
    save_path.write_text(json.dumps(list(data_cache.values()), indent='\t'))

    global stats_cache
    stats_cache = get_data_stats(data_cache)
    return {}, 200


@app.route('/stats')
def stats():
    return render_template('stats.html',
                           times=FormContent.times,
                           topics=FormContent.topics,
                           background=FormContent.background,
                           languages=FormContent.languages,
                           data=stats_cache)


if __name__ == '__main__':
    app.run(host='0.0.0.0', port=9700, debug=False)