package com.btk5h.skriptdb.skript;

import com.btk5h.skriptdb.SkriptDB;
import com.zaxxer.hikari.HikariDataSource;

import org.bukkit.event.Event;

import java.util.HashMap;
import java.util.Map;

import ch.njol.skript.Skript;
import ch.njol.skript.lang.Expression;
import ch.njol.skript.lang.ExpressionType;
import ch.njol.skript.lang.SkriptParser;
import ch.njol.skript.lang.util.SimpleExpression;
import ch.njol.skript.util.Timespan;
import ch.njol.util.Kleenean;

/**
 * Stores the connection information for a data source. This should be saved to a variable in a
 * `script load` event or manually through an effect command.
 *
 * The url format for your database may vary! The example provided uses a MySQL database.
 *
 * @name Data Source
 * @index -1
 * @pattern [the] data(base|[ ]source) [(of|at)] %string% [with [a] [max[imum]] [connection] life[ ]time of %timespan%]"
 * @return datasource
 * @example set {sql} to the database "mysql://localhost:3306/mydatabase?user=admin&password=12345&useSSL=false"
 * @since 0.1.0
 */
public class ExprDataSource extends SimpleExpression<HikariDataSource> {
  static {
    Skript.registerExpression(ExprDataSource.class, HikariDataSource.class,
        ExpressionType.COMBINED, "[the] data(base|[ ]source) [(of|at)] %string% " +
            "[with [a] [max[imum]] [connection] life[ ]time of %-timespan%]");
  }

  private static Map<String, HikariDataSource> connectionCache = new HashMap<>();

  private Expression<String> url;
  private Expression<Timespan> maxLifetime;

  @Override
  protected HikariDataSource[] get(Event e) {
    String jdbcUrl = url.getSingle(e);
    if (jdbcUrl == null) {
      return null;
    }

    if (!jdbcUrl.startsWith("jdbc:")) {
      jdbcUrl = "jdbc:" + jdbcUrl;
    }

    if (connectionCache.containsKey(jdbcUrl)) {
      return new HikariDataSource[]{connectionCache.get(jdbcUrl)};
    }

    HikariDataSource ds = new HikariDataSource();

    //allow specifying of own sql driver class name
    if (!SkriptDB.getInstance().getConfig().getString("sql-driver-class-name", "default").equals("default")) {
      ds.setDriverClassName(SkriptDB.getInstance().getConfig().getString("sql-driver-class-name"));
    }
    ds.setJdbcUrl(jdbcUrl);

    if (maxLifetime != null) {
      Timespan l = maxLifetime.getSingle(e);

      if (l != null) {
        ds.setMaxLifetime(l.getMilliSeconds());
      }
    }

    connectionCache.put(jdbcUrl, ds);

    return new HikariDataSource[]{ds};
  }

  @Override
  public boolean isSingle() {
    return true;
  }

  @Override
  public Class<? extends HikariDataSource> getReturnType() {
    return HikariDataSource.class;
  }

  @Override
  public String toString(Event e, boolean debug) {
    return "datasource " + url.toString(e, debug);
  }

  @SuppressWarnings("unchecked")
  @Override
  public boolean init(Expression<?>[] exprs, int matchedPattern, Kleenean isDelayed,
                      SkriptParser.ParseResult parseResult) {
    url = (Expression<String>) exprs[0];
    maxLifetime = (Expression<Timespan>) exprs[1];
    return true;
  }
}