inmemory.js

const BLACKLIST = { dbms: 1 };
const ISOP = { '+': 1, '-': 1, '*': 1, '/': 1, '=': 1, '!': 1, '#': 1 };
const InMemory = require('total4/inmemory');

var INSTANCES = {};

function select(client, cmd) {

	var builder = cmd.builder;
	var opt = builder.options;
	var filter = WHERE(builder, null, null);
	var fields = FIELDS(builder);

	// opt.table
	var data = {};

	if (fields)
		data.fields = fields;

	data.filter = filter.filter;
	data.filterarg = { arg: filter.arg };

	if (filter.sort)
		data.sort = filter.sort;

	if (filter.take)
		data.take = filter.take;

	if (filter.skip)
		data.skip = filter.skip;

	F.$events.dbms && EMIT('dbms', 'select', opt.table, opt.db, builder);

	var conn = INSTANCES[opt.table] || (INSTANCES[opt.table] = InMemory.load(PATH.databases(opt.table + '.inmemory')));

	conn.find().assign(data).callback(function(err, response, meta) {

		builder.db.busy = false;

		var rows = response;
		err && client.$opt.onerror && client.$opt.onerror(err, data);

		if (opt.first)
			rows = rows[0] || null;

		// checks joins
		if (!err && builder.$joins) {
			client.$dbms._joins(rows, builder);
			setImmediate(builder.db.$next);
		} else
			builder.$callback(err, rows, meta.count);
	});
}

function check(client, cmd) {
	var builder = cmd.builder;
	var opt = builder.options;
	var filter = WHERE(builder);
	var data = {};

	data.filter = filter.filter;
	data.filterarg = { arg: filter.arg };
	data.take = 1;
	data.limit = 1;
	data.first = true;

	if (!cmd.value && builder.options.params)
		cmd.value = [];

	builder.db.$debug && builder.db.$debug(data);
	F.$events.dbms && EMIT('dbms', 'select', opt.table, opt.db, builder);

	var conn = INSTANCES[opt.table] || (INSTANCES[opt.table] = InMemory.load(PATH.databases(opt.table + '.inmemory')));

	conn.find().assign(data).callback(function(err, response, meta) {
		builder.db.busy = false;
		var is = !err && !!response;
		err && client.$opt.onerror && client.$opt.onerror(err, data);
		builder.$callback(err, is, meta.count);
	});
}

function query(client, cmd) {
	var builder = cmd.builder;
	var opt = builder.options;
	var filter = WHERE(builder);
	var data = {};

	data.filter = filter.filter;
	data.filterarg = { arg: filter.arg };
	data.scalar = cmd.query;
	data.scalararg = cmd.value || {};

	builder.db.$debug && builder.db.$debug(data);
	F.$events.dbms && EMIT('dbms', 'query', opt.table, opt.db, builder);
	var conn = INSTANCES[opt.table] || (INSTANCES[opt.table || opt.db] = InMemory.load(PATH.databases(opt.table || opt.db + '.inmemory')));

	conn.find().assign(data).callback(function(err, response, meta) {
		builder.db.busy = false;
		err && client.$opt.onerror && client.$opt.onerror(err, data);
		builder.$callback(err, response, meta.count);
	});
}

function scalar(client, cmd) {

	var builder = cmd.builder;
	var opt = builder.options;
	var scalar = '';
	var data = {};
	var filter = WHERE(builder);

	data.filter = filter.filter;
	data.filterarg = { arg: filter.arg };
	data.scalar = scalar;
	data.scalararg = {};

	var name = cmd.name;
	if (name) {
		var index = name.indexOf(' as ');
		if (index !== -1) {
			name = name.substring(index + 4);
			cmd.name = cmd.name.substring(0, index);
		}
	}

	switch (cmd.scalar) {
		case 'group':
			data.scalar = cmd.field ? ('var k=doc.' + cmd.name + '+\'\';if (arg[k]){arg[k]+=doc.' + cmd.field + '||0}else{arg[k]=doc.' + cmd.field + '||0}') : ('var k=doc.' + cmd.name + '+\'\';if (arg[k]){arg[k]++}else{arg[k]=1}');
			break;
		default:
			if (cmd.field) {
				data.scalar = 'var k=doc.' + cmd.name + '+\'\';if (arg[k]){tmp.bk=doc.' + cmd.field + '||0;' + (cmd.scalar === 'max' ? 'if(tmp.bk>arg[k])arg[k]=tmp.bk' : cmd.scalar === 'min' ? 'if(tmp.bk<arg[k])arg[k]=tmp.bk' : 'arg[k]+=tmp.bk') + '}else{arg[k]=doc.' + cmd.field + '||0}';
			} else {
				// min, max, sum, count
				data.scalar = cmd.name ? 'if (doc.{0}!=null){tmp.val=doc.{0};arg.count+=1;arg.min=arg.min==null?tmp.val:arg.min>tmp.val?tmp.val:arg.min;arg.max=arg.max==null?tmp.val:arg.max<tmp.val?tmp.val:arg.max;if (!(tmp.val instanceof Date))arg.sum+=tmp.val}'.format(cmd.name) : 'if (doc){arg.count+=1}';
				data.scalararg.count = 0;
				data.scalararg.sum = 0;
			}
			break;
	}

	builder.db.$debug && builder.db.$debug(data);
	F.$events.dbms && EMIT('dbms', 'select', opt.table, opt.db, builder);

	var conn = INSTANCES[opt.table] || (INSTANCES[opt.table] = InMemory.load(PATH.databases(opt.table + '.inmemory')));

	conn.find().assign(data).callback(function(err, response, meta) {

		builder.db.busy = false;

		var output;

		if (cmd.field || cmd.scalar === 'group') {
			output = [];
			for (var key in response) {
				var obj = {};
				obj[name] = key;
				obj.count = response[key];
				output.push(obj);
			}
		} else
			output = cmd.scalar === 'avg' ? (response[cmd.scalar].max / response[cmd.scalar].min) : response[cmd.scalar];

		err && client.$opt.onerror && client.$opt.onerror(err, data);
		builder.$callback(err, output, meta.count);
	});
}

function insert(client, cmd) {

	var builder = cmd.builder;

	cmd.builder.options.transform && cmd.builder.options.transform(cmd.builder.value, cmd.builder.db.$output, cmd.builder.db.$lastoutput);

	var keys = Object.keys(builder.value);
	var opt = builder.options;
	var doc = {};

	for (var i = 0; i < keys.length; i++) {
		var key = keys[i];
		var val = builder.value[key];
		if (val === undefined || BLACKLIST[key])
			continue;

		if (builder.options.fields && builder.options.fields.length) {
			var skip = true;
			for (var j = 0; j < builder.options.fields.length; j++) {
				var field = builder.options.fields[j];
				if (field[0] === '-') {
					field = field.substring(1);
					if (field === key || (ISOP[key[0]] && field === key.substring(1))) {
						skip = true;
						break;
					}
					skip = false;
				} else if (field === key || (ISOP[key[0]] && field === key.substring(1))) {
					skip = false;
					break;
				} else
					skip = false;
			}

			if (skip)
				continue;
		}

		switch (key[0]) {
			case '-':
			case '+':
			case '*':
			case '/':
			case '>':
			case '<':
				key = key.substring(1);
				break;
			case '=':
				key = key.substring(1);
				break;
			case '#':
				break;
			case '!':
				// toggle
				key = key.substring(1);
				if (val)
					val = true;
				else
					val = false;
				break;
		}

		doc[key] = val == null ? null : typeof(val) === 'function' ? val(builder.value) : val;
	}

	// builder.db.$debug && builder.db.$debug(q);
	F.$events.dbms && EMIT('dbms', 'insert', opt.table, opt.db, builder);

	var data = {};
	data.payload = doc;

	var conn = INSTANCES[opt.table] || (INSTANCES[opt.table] = InMemory.load(PATH.databases(opt.table + '.inmemory')));

	conn.insert().assign(data).callback(function(err, response) {
		builder.db.busy = false;
		err && client.$opt.onerror && client.$opt.onerror(err, data);
		builder.$callback(err, err == null ? response : 0);
	});
}

function insertexists(client, cmd) {

	var builder = cmd.builder;
	var opt = builder.options;
	var filter = WHERE(cmd.builder);
	var data = {};

	data = {};
	data.take = 1;
	data.filter = filter.filter;
	data.filterarg = { arg: filter.arg };
	data.limit = 1;
	data.first = true;

	F.$events.dbms && EMIT('dbms', 'select', opt.table, data, builder);

	var conn = INSTANCES[opt.table] || (INSTANCES[opt.table] = InMemory.load(PATH.databases(opt.table + '.inmemory')));

	conn.find().assign(data).callback(function(err, response) {
		builder.db.busy = false;
		err && client.$opt.onerror && client.$opt.onerror(err, data);
		if (response)
			builder.$callback(err, 0);
		else
			insert(client, cmd);
	});
}

function modify(client, cmd) {

	cmd.builder.options.transform && cmd.builder.options.transform(cmd.builder.value, cmd.builder.db.$output, cmd.builder.db.$lastoutput);

	var keys = Object.keys(cmd.builder.value);
	var params = [];
	var arr = [];
	var builder = [];
	var tmp;
	for (var i = 0; i < keys.length; i++) {
		var key = keys[i];
		var val = cmd.builder.value[key];

		if (val === undefined || BLACKLIST[key])
			continue;

		if (cmd.builder.options.equal && cmd.builder.options.equal.indexOf(key) !== -1)
			continue;

		if (cmd.builder.options.fields && cmd.builder.options.fields.length) {
			var skip = true;
			for (var j = 0; j < cmd.builder.options.fields.length; j++) {
				var field = cmd.builder.options.fields[j];
				if (field[0] === '-') {
					field = field.substring(1);
					if (field === key || (ISOP[key[0]] && field === key.substring(1))) {
						skip = true;
						break;
					}
					skip = false;
				} else if (field === key || (ISOP[key[0]] && field === key.substring(1))) {
					skip = false;
					break;
				} else
					skip = false;
			}

			if (skip)
				continue;
		}

		var c = key[0];

		if (typeof(val) === 'function')
			val = val(cmd.builder.value);

		switch (c) {
			case '-':
			case '+':
			case '*':
			case '/':
				key = key.substring(1);
				params.push(val ? val : 0);
				builder.push('doc.' + key + '=(doc.' + key + '||0)' + c + push(arr, val ? val : 0));
				break;
			case '>':
			case '<':
				tmp = push(arr, val ? val : 0);
				key = key.substring(1);
				builder.push('doc.' + key + '=(doc.' + key + '||0)' + c + tmp + '?(doc.' + key + '||0):' + tmp);
				break;
			case '!':
				// toggle
				key = key.substring(1);
				builder.push('doc.' + key + '=!doc.' + key);
				break;
			case '=':
			case '#':
				// raw
				builder.push('doc.' + key + '=' + val);
				break;
			default:
				builder.push('doc.' + key + '=' + push(arr, val));
				break;
		}
	}

	var opt = cmd.builder.options;

	if (opt.equal) {
		for (var i = 0; i < opt.equal.length; i++)
			cmd.builder.where(opt.equal[i], builder.value[opt.equal[i]]);
	}

	var filter = WHERE(cmd.builder);
	var data = {};

	data.filter = filter.filter;
	data.filterarg = { arg: filter.arg };
	data.modify = builder.join(';');
	data.modifyarg = { arg: arr };

	if (filter.take)
		data.take = filter.take;

	if (filter.skip)
		data.skip = filter.skip;

	cmd.builder.db.$debug && cmd.builder.db.$debug(data);
	F.$events.dbms && EMIT('dbms', 'update', data, builder);

	data.db = opt.table;

	var conn = INSTANCES[opt.table] || (INSTANCES[opt.table] = InMemory.load(PATH.databases(opt.table + '.inmemory')));

	conn.update().assign(data).callback(function(err, response, meta) {
		cmd.builder.db.busy = false;
		err && client.$opt.onerror && client.$opt.onerror(err, data);
		if (!response && cmd.insert) {
			if (cmd.insert !== true)
				cmd.builder.value = cmd.insert;
			cmd.builder.options.insert && cmd.builder.options.insert(cmd.builder.value, cmd.builder.options.insertparams);
			insert(client, cmd);
		} else
			cmd.builder.$callback(err, response, meta.count);
	});
}

function remove(client, cmd) {
	var builder = cmd.builder;
	var opt = cmd.builder.options;
	var filter = WHERE(builder);
	var data = {};
	data.filter = filter.filter;
	data.filterarg = { arg: filter.arg };

	if (filter.take)
		data.take = filter.take;

	if (filter.skip)
		data.skip = filter.skip;

	builder.db.$debug && builder.db.$debug(data);
	F.$events.dbms && EMIT('dbms', 'delete', opt.table, opt.db, builder);

	var conn = INSTANCES[opt.table] || (INSTANCES[opt.table] = InMemory.load(PATH.databases(opt.table + '.inmemory')));

	conn.remove().assign(data).callback(function(err, response, meta) {
		cmd.builder.db.busy = false;
		err && client.$opt.onerror && client.$opt.onerror(err, data);
		cmd.builder.$callback(err, response, meta.count);
	});
}

function clientcommand(cmd, client) {
	switch (cmd.type) {
		case 'transaction':
		case 'end':
		case 'commit':
		case 'rollback':
			break;
		case 'find':
		case 'read':
		case 'list':
			select(client, cmd);
			break;
		case 'check':
			check(client, cmd);
			break;
		case 'scalar':
			scalar(client, cmd);
			break;
		case 'insert':
			if (cmd.unique)
				insertexists(client, cmd);
			else
				insert(client, cmd);
			break;

		case 'modify2':
			var cb = cmd.builder.$callback;
			cmd.builder.$callback = function(err, response) {
				cmd.builder.options.fields = null;
				if (err) {
					cb.call(cmd.builder, err, 0);
				} else if (response) {
					var mod = cmd.fn(response);
					if (mod) {
						cmd.builder.value = mod;
						cmd.builder.$callback = cb;
						if (cmd.builder.value.$clean)
							cmd.builder.value = cmd.builder.value.$clean();
						modify(client, cmd);
					} else
						cb.call(cmd.builder, err, 0);
				} else {
					if (cmd.insert) {
						mod = cmd.fn(null);
						if (mod) {
							cmd.builder.value = mod;
							cmd.builder.$callback = cb;
							insert(client, cmd);
						} else
							cb.call(cmd.builder, err, 0);
					} else {
						cb.call(cmd.builder, err, 0);
					}
				}
			};
			select(client, cmd);
			break;

		case 'update':
		case 'modify':
			modify(client, cmd);
			break;
		case 'remove':
			remove(client, cmd);
			break;
		case 'query':
			query(client, cmd);
			break;
		default:
			cmd.builder.$callback(new Error('Operation "' + cmd.type + '" not found'));
			break;
	}
}

exports.run = function(opt, self, cmd) {
	self.$op = null;
	self.busy = true;
	self.$opt = opt;
	clientcommand(cmd, opt);
};

function push(arr, value) {
	return 'arg.arg[' + (arr.push(value) - 1) + ']';
}

function WHERE(builder) {

	var condition = [];
	var sort = '';
	var op = '&&';
	var opuse = false;
	var arg = [];

	for (var i = 0; i < builder.$commands.length; i++) {
		var cmd = builder.$commands[i];

		if (builder.options.islanguage && cmd.name && cmd.name[cmd.name.length - 1] === '§')
			cmd.name = cmd.name.substring(0, cmd.name.length - 1) + (builder.options.language || '');

		switch (cmd.type) {
			case 'where':
				opuse && condition.length && condition.push(op);
				if (cmd.compare === '<>')
					cmd.compare = '!=';
				else if (cmd.compare === '=')
					cmd.compare = '==';

				if (cmd.value === undefined)
					condition.push(cmd.name);
				else {
					var tmp = push(arg, cmd.value);
					condition.push('doc.' + cmd.name + ' instanceof Array?(doc.' + cmd.name + '.indexOf(' + tmp + ')' + (cmd.compare === '==' ? '!=' : '==') + '-1):(doc.' + cmd.name + cmd.compare + tmp + ')');
				}

				break;
			case 'custom':
				cmd.fn.call(builder, builder, builder.db.$output, builder.db.$lastoutput);
				break;
			case 'in':

				if (typeof(cmd.value) === 'function')
					cmd.value = cmd.value();

				if (cmd.value instanceof Array) {

					if (cmd.field) {
						var tmp = [];
						for (var j = 0; j < cmd.value.length; j++) {
							if (cmd.value[j])
								tmp.push(cmd.value[j][cmd.field]);
						}
						cmd.value = tmp;
					}

					opuse && condition.length && condition.push(op);
					condition.push(push(arg, cmd.value) + '.indexOf(doc.' + cmd.name + ')!==-1');
				} else {
					opuse && condition.length && condition.push(op);
					condition.push('doc.' + cmd.name + '==' + push(arg, cmd.field ? cmd.value[cmd.field] : cmd.value));
				}
				break;
			case 'notin':

				if (typeof(cmd.value) === 'function')
					cmd.value = cmd.value();

				if (cmd.value instanceof Array) {

					if (cmd.field) {
						var tmp = [];
						for (var j = 0; j < cmd.value.length; j++) {
							if (cmd.value[j])
								tmp.push(cmd.value[j][cmd.field]);
						}
						cmd.value = tmp;
					}

					opuse && condition.length && condition.push(op);
					condition.push(push(arg, cmd.value) + '.indexOf(doc.' + cmd.name + ')===-1');
				} else {
					opuse && condition.length && condition.push(op);
					condition.push('doc.' + cmd.name + '!=' + push(arg, cmd.field ? cmd.value[cmd.field] : cmd.value));
				}

				break;
			case 'between':
				opuse && condition.length && condition.push(op);
				condition.push('(doc.' + cmd.name + '>=' + push(arg, cmd.a) + '&&doc.' + cmd.name + '<=' + push(arg, cmd.b) + ')');
				break;
			case 'search':
				// tmp = ESCAPE((!cmd.compare || cmd.compare === '*' ? ('%' + cmd.value + '%') : (cmd.compare === 'beg' ? ('%' + cmd.value) : (cmd.value + '%'))));
				opuse && condition.length && condition.push(op);
				condition.push('doc.' + cmd.name + '.indexOf(' + push(arg, cmd.value) + ')!==-1');
				break;

			case 'searchfull':
				// tmp = ESCAPE('%' + cmd.value.toLowerCase().replace(/y/g, 'i') + '%');
				// opuse && condition.length && condition.push(op);
				// condition.push('REPLACE(LOWER(to_tsvector(' + builder.options.table + '::text)::text), \'y\', \'i\') ILIKE ' + tmp);
				break;

			case 'searchall':
				// tmp = '';
				// for (var j = 0; j < cmd.value.length; j++)
				// 	tmp += (tmp ? ' AND ' : '') + cmd.name + ' ILIKE ' + ESCAPE('%' + cmd.value[j] + '%');
				// opuse && condition.length && condition.push(op);
				// condition.push('(' + (tmp || '0=1') + ')');
				break;

			case 'fulltext':
				// tmp = ESCAPE('%' + cmd.value.toLowerCase() + '%');
				// opuse && condition.length && condition.push(op);
				// condition.push('LOWER(' + cmd.name + ') ILIKE ' + tmp);
				break;
			case 'contains':
				opuse && condition.length && condition.push(op);
				condition.push('!!doc.' + cmd.name);
				break;
			case 'query':
				opuse && condition.length && condition.push(op);
				condition.push(cmd.query);
				break;
			case 'permit':
				break;
			case 'empty':
				opuse && condition.length && condition.push(op);
				condition.push('!doc.' + cmd.name);
				break;
			case 'month':
			case 'year':
			case 'day':
			case 'hour':
			case 'minute':
				opuse && condition.length && condition.push(op);
				var type = cmd.type === 'month' ? 'Month' : cmd.type === 'year' ? 'FullYear' : cmd.type === 'day' ? 'Date' : cmd.type === 'minute' ? 'Minutes' : cmd.type === 'hours' ? 'Hours' : 'Seconds';
				condition.push('doc.' + cmd.name + ' instanceof Date?(doc.' + cmd.name + '.get' + type + '()===' + cmd.value + '):false');
				break;
			case 'date':
				opuse && condition.length && condition.push(op);
				condition.push(cmd.value instanceof Date ? ('doc.' + cmd.name + ' instanceof Date?(doc.' + cmd.name + '.getDate()===' + cmd.value.getDate() + '&&doc.' + cmd.name + '.getMonth()===' + cmd.value.getMonth() + '&&doc.' + cmd.name + '.getFullYear()===' + cmd.value.getFullYear() + '):false') : ('!doc.' + cmd.name));
				break;
			case 'or':
				opuse && condition.length && condition.push(op);
				op = '||';
				opuse = false;
				condition.push('(');
				continue;
			case 'end':
				condition.push(')');
				op = '&&';
				break;
			case 'and':
				opuse && condition.length && condition.push(op);
				op = '&&';
				break;
			case 'sort':
				sort = cmd.name + '_' + (cmd.desc ? 'desc' : 'asc');
				break;
			case 'regexp':
				// tmp = cmd.value.toString().substring(1);
				// var g = '~';
				// if (tmp[tmp.length - 1] === 'i') {
				// 	tmp = tmp.substring(0, tmp.length - 2);
				// 	g = '~*';
				// } else
				// 	tmp = tmp.substring(0, tmp.length - 1);
				// opuse && condition.length && condition.push(op);
				// condition.push(cmd.name + g + '\'' + tmp + '\'');
				break;
		}
		opuse = true;
	}

	// var query = (condition.length ? (' WHERE ' + condition.join(' ')) : '') + (group ? (' GROUP BY ' + group) : '');
	return { filter: condition.length ? condition.join('') : 'true', arg: arg, sort: sort, take: builder.options.take, skip: builder.options.skip };
}

function FIELDS(builder) {
	var fields = builder.options.fields || '';
	return fields + (fields && fields.length && builder.$joinmeta ? (',' + builder.$joinmeta.a) : '');
}