/*
 * Copyright (C)2005-2019 Haxe Foundation
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 * DEALINGS IN THE SOFTWARE.
 */

package sys.db;

private class SqliteConnection implements Connection {
	var c:Dynamic;

	public function new(file:String) {
		c = _connect(untyped file.__s);
	}

	public function close() {
		_close(c);
	}

	public function request(s:String):ResultSet {
		try {
			return new SqliteResultSet(_request(c, untyped s.__s));
		} catch (e:String) {
			throw "Error while executing " + s + " (" + e + ")";
		}
	}

	public function escape(s:String) {
		return s.split("'").join("''");
	}

	public function quote(s:String) {
		if (s.indexOf("\000") >= 0)
			return "x'" + new String(untyped _encode(s.__s, "0123456789ABCDEF".__s)) + "'";
		return "'" + s.split("'").join("''") + "'";
	}

	public function addValue(s:StringBuf, v:Dynamic) {
		var t = untyped __dollar__typeof(v);
		if (untyped (t == __dollar__tint || t == __dollar__tnull))
			s.add(v);
		else if (untyped t == __dollar__tbool)
			s.add(if (v) 1 else 0);
		else
			s.add(quote(Std.string(v)));
	}

	public function lastInsertId() {
		return _last_id(c);
	}

	public function dbName() {
		return "SQLite";
	}

	public function startTransaction() {
		request("BEGIN TRANSACTION");
	}

	public function commit() {
		request("COMMIT");
		startTransaction(); // match mysql usage
	}

	public function rollback() {
		request("ROLLBACK");
		startTransaction(); // match mysql usage
	}

	static var _encode = neko.Lib.load("std", "base_encode", 2);
	static var _connect = neko.Lib.load("sqlite", "connect", 1);
	static var _close = neko.Lib.load("sqlite", "close", 1);
	static var _request = neko.Lib.load("sqlite", "request", 2);
	static var _last_id = neko.Lib.load("sqlite", "last_insert_id", 1);
}

private class SqliteResultSet implements ResultSet {
	public var length(get, null):Int;
	public var nfields(get, null):Int;

	var r:Dynamic;
	var cache:List<Dynamic>;

	public function new(r) {
		cache = new List();
		this.r = r;
		hasNext(); // execute the request
	}

	function get_length() {
		if (nfields != 0) {
			while (true) {
				var c = doNext();
				if (c == null)
					break;
				cache.add(c);
			}
			return cache.length;
		}
		return result_get_length(r);
	}

	function get_nfields() {
		return result_get_nfields(r);
	}

	public function hasNext() {
		var c = next();
		if (c == null)
			return false;
		cache.push(c);
		return true;
	}

	public function next():Dynamic {
		var c = cache.pop();
		if (c != null)
			return c;
		return doNext();
	}

	private function doNext():Dynamic {
		var c = result_next(r);
		if (c == null)
			return null;
		untyped {
			var f = __dollar__objfields(c);
			var i = 0;
			var l = __dollar__asize(f);
			while (i < l) {
				var v = __dollar__objget(c, f[i]);
				if (__dollar__typeof(v) == __dollar__tstring)
					__dollar__objset(c, f[i], new String(v));
				i = i + 1;
			}
		}
		return c;
	}

	public function results():List<Dynamic> {
		var l = new List();
		while (true) {
			var c = next();
			if (c == null)
				break;
			l.add(c);
		}
		return l;
	}

	public function getResult(n:Int) {
		return new String(result_get(r, n));
	}

	public function getIntResult(n:Int):Int {
		return result_get_int(r, n);
	}

	public function getFloatResult(n:Int):Float {
		return result_get_float(r, n);
	}

	public function getFieldsNames():Array<String> {
		return null;
	}

	static var result_next = neko.Lib.load("sqlite", "result_next", 1);
	static var result_get_length = neko.Lib.load("sqlite", "result_get_length", 1);
	static var result_get_nfields = neko.Lib.load("sqlite", "result_get_nfields", 1);
	static var result_get = neko.Lib.load("sqlite", "result_get", 2);
	static var result_get_int = neko.Lib.load("sqlite", "result_get_int", 2);
	static var result_get_float = neko.Lib.load("sqlite", "result_get_float", 2);
}

@:coreApi class Sqlite {
	public static function open(file:String):Connection {
		return new SqliteConnection(file);
	}
}