'use strict';

var _ = require('lodash');

var Node = require(__dirname);

var ParameterNode = require(__dirname + '/parameter');

// Process values, wrapping them in ParameterNode if necessary.

var processParams = function(val) {

var helper = function(v) {

return v.toNode ? v.toNode() : new ParameterNode(v);

};

return Array.isArray(val) ? val.map(helper) : helper(val);

};

// Value expressions can be composed to form new value expressions.

// Value expressions include binary expressions and unary expressions

// so far. ValueExpressionMixin is evaluated at runtime, hence the

// "thunk" around it.

var ValueExpressionMixin = module.exports = function() {

var BinaryNode = require(__dirname + '/binary');

var TernaryNode = require(__dirname + '/ternary');

var UnaryNode = require(__dirname + '/unary');

var binaryMethod = function(operator) {

return function(val) {

return new BinaryNode({

left: this.toNode(),

operator: operator,

right: processParams(val)

});

};

};

var unaryMethod = function(operator) {

/*jshint unused: false */

return function(val) {

return new UnaryNode({

left: this.toNode(),

operator: operator

});

};

};

var ternaryMethod = function(operator, separator) {

return function(middle, right) {

return new TernaryNode({

left: this.toNode(),

middle: processParams(middle),

operator: operator,

right: processParams(right),

separator: separator

});

};

};

return {

isNull : unaryMethod('IS NULL'),

isNotNull: unaryMethod('IS NOT NULL'),

or : binaryMethod('OR'),

and : binaryMethod('AND'),

equals : binaryMethod('='),

equal : binaryMethod('='),

notEquals: binaryMethod('<>'),

notEqual : binaryMethod('<>'),

gt : binaryMethod('>'),

gte : binaryMethod('>='),

lt : binaryMethod('<'),

lte : binaryMethod('<='),

add : binaryMethod('+'),

subtract : binaryMethod('-'),

multiply : binaryMethod('*'),

divide : binaryMethod('/'),

modulo : binaryMethod('%'),

like : binaryMethod('LIKE'),

notLike : binaryMethod('NOT LIKE'),

in : binaryMethod('IN'),

notIn : binaryMethod('NOT IN'),

between : ternaryMethod('BETWEEN', 'AND')

};

};