import { PrismaClient } from '@prisma/client';
import chalk from 'chalk';
import {
  FILTER_IGNORED,
  MYSQL,
  MYSQL_DATE_FORMATS,
  POSTGRESQL,
  POSTGRESQL_DATE_FORMATS,
} from 'lib/constants';
import { getDatabase } from './db';
import moment from 'moment-timezone';

const options = {
  log: [
    {
      emit: 'event',
      level: 'query',
    },
  ],
};

function logQuery(e) {
  console.log(chalk.yellow(e.params), '->', e.query, chalk.greenBright(`${e.duration}ms`));
}

function getPrismaClient(options) {
  const prisma = new PrismaClient(options);

  if (process.env.LOG_QUERY) {
    prisma.$on('query', logQuery);
  }

  return prisma;
}
const prisma = global.prisma || getPrismaClient(options);

if (process.env.NODE_ENV !== 'production') {
  global.prisma = prisma;
}

export { prisma };

export function getDateQuery(field, unit, timezone) {
  const db = getDatabase();

  if (db === POSTGRESQL) {
    if (timezone) {
      return `to_char(date_trunc('${unit}', ${field} at time zone '${timezone}'), '${POSTGRESQL_DATE_FORMATS[unit]}')`;
    }
    return `to_char(date_trunc('${unit}', ${field}), '${POSTGRESQL_DATE_FORMATS[unit]}')`;
  }

  if (db === MYSQL) {
    if (timezone) {
      const tz = moment.tz(timezone).format('Z');

      return `date_format(convert_tz(${field},'+00:00','${tz}'), '${MYSQL_DATE_FORMATS[unit]}')`;
    }

    return `date_format(${field}, '${MYSQL_DATE_FORMATS[unit]}')`;
  }
}

export function getFilterQuery(table, column, filters = {}, params = []) {
  const query = Object.keys(filters).reduce((arr, key) => {
    const filter = filters[key];

    if (filter === undefined || filter === FILTER_IGNORED) {
      return arr;
    }

    switch (key) {
      case 'url':
        if (table === 'pageview' || table === 'event') {
          arr.push(`and ${table}.${key}=$${params.length + 1}`);
          params.push(decodeURIComponent(filter));
        }
        break;

      case 'os':
      case 'browser':
      case 'device':
      case 'country':
        if (table === 'session') {
          arr.push(`and ${table}.${key}=$${params.length + 1}`);
          params.push(decodeURIComponent(filter));
        }
        break;

      case 'event_name':
        if (table === 'event') {
          arr.push(`and ${table}.${key}=$${params.length + 1}`);
          params.push(decodeURIComponent(filter));
        }
        break;

      case 'referrer':
        if (table === 'pageview' || table === 'event') {
          arr.push(`and ${table}.referrer like $${params.length + 1}`);
          params.push(`%${decodeURIComponent(filter)}%`);
        }
        break;

      case 'domain':
        if (table === 'pageview') {
          arr.push(`and ${table}.referrer not like $${params.length + 1}`);
          arr.push(`and ${table}.referrer not like '/%'`);
          params.push(`%://${filter}/%`);
        }
        break;

      case 'query':
        if (table === 'pageview') {
          arr.push(`and ${table}.url like '%?%'`);
        }
    }

    return arr;
  }, []);

  return query.join('\n');
}

export function parseFilters(table, column, filters = {}, params = [], sessionKey = 'session_id') {
  const { domain, url, event_url, referrer, os, browser, device, country, event_name, query } =
    filters;

  const pageviewFilters = { domain, url, referrer, query };
  const sessionFilters = { os, browser, device, country };
  const eventFilters = { url: event_url, event_name };

  return {
    pageviewFilters,
    sessionFilters,
    eventFilters,
    event: { event_name },
    joinSession:
      os || browser || device || country
        ? `inner join session on ${table}.${sessionKey} = session.${sessionKey}`
        : '',
    pageviewQuery: getFilterQuery('pageview', column, pageviewFilters, params),
    sessionQuery: getFilterQuery('session', column, sessionFilters, params),
    eventQuery: getFilterQuery('event', column, eventFilters, params),
  };
}

export async function runQuery(query) {
  return query.catch(e => {
    throw e;
  });
}

export async function rawQuery(query, params = []) {
  const db = getDatabase(process.env.DATABASE_URL, process.env.DATABASE_TYPE);

  if (db !== POSTGRESQL && db !== MYSQL) {
    return Promise.reject(new Error('Unknown database.'));
  }

  const sql = db === MYSQL ? query.replace(/\$[0-9]+/g, '?') : query;

  return runQuery(prisma.$queryRawUnsafe.apply(prisma, [sql, ...params]));
}