pfhwyigou/wechat/web/js/house/canvas/calculator.js

(function ($) {
    Calculator = function (opts) {
        var obj = this;
        this.rate = new Array();

        //本息本金还贷
        this.loanResult = function (property, model) {
            var data = {};
            var month = property.year * 12;
            data.month = month;
            if (property.type == "3") { // 组合型贷款(组合型贷款的计算，只和商业贷款额、和公积金贷款额有关，和按贷款总额计算无关)
                data.total = "略";     //房款总额
                data.firstPay = 0;     //首次还款
                data.totalLoan = parseFloat(property.biz) + parseFloat(property.acc);   //总贷款

                var bizRate = getRate(2, property.year, property.rate); //商贷利率
                var accRate = getRate(1, property.year, property.rate); //公积金利率

                if (model == 1) {    //本金还款
                    var all_total = 0, items = new Array(), pay = 0;
                    for (j = 0; j < month; j++) {
                        pay = getMonthPayForInterest(bizRate, property.biz, month, j) + getMonthPayForInterest(accRate, property.acc, month, j);
                        all_total += pay;
                        pay = Math.round(pay * 100) / 100;
                        items.push({ month: j + 1, pay: pay });
                    }
                    data.perMonthPay = items;   //每月还款数组
                    data.totalPay = Math.round(all_total * 100) / 100;  //还款总额
                    data.interestPay = Math.round((all_total - data.totalLoan) * 100) / 100;    //支付利息款
                } else {  //本息还款
                    data.perMonthPay = getMonthPayForPrincipal(bizRate, property.biz, month) + getMonthPayForPrincipal(accRate, property.acc, month);
                    data.totalPay = Math.round(data.perMonthPay * month * 100) / 100;
                    data.interestPay = Math.round((data.totalPay - data.totalLoan) * 100) / 100;
                }
            } else {
                var _rate = getRate(property.type, property.year, property.rate); //利率
                if (property.calType == 2) {     
                    data.totalLoan = property.biz;
                } else {
                    data.totalLoan = property.acc;
                }

                if (model == 1) {    //本金还款
                    var all_total = 0, items = new Array(), pay = 0;
                    for (j = 0; j < month; j++) {
                        pay = getMonthPayForInterest(_rate, data.totalLoan, month, j);
                        all_total += pay;
                        pay = Math.round(pay * 100) / 100;
                        items.push({ month: j + 1, pay: pay });
                    }
                    data.perMonthPay = items;   //每月还款数组
                    data.totalPay = Math.round(all_total * 100) / 100;  //还款总额
                    data.interestPay = Math.round((all_total - data.totalLoan) * 100) / 100;    //支付利息款
                } else {        //本息还款
                    data.perMonthPay = getMonthPayForPrincipal(_rate, data.totalLoan, month);
                    data.totalPay = Math.round(data.perMonthPay * month * 100) / 100;
                    data.interestPay = Math.round((data.totalPay - data.totalLoan) * 100) / 100;
                    data.perMonthPay = Math.round(data.perMonthPay * 100) / 100;
                }
            }

            return data;
        };

        this.getRate = function (type, year, rateIndex) {
            var currRate = obj.rate[rateIndex], item, rate = 0;
            for (var i = 0; i < currRate.items.length; i++) {
                item = currRate.items[i];
                if (year > item.min && year <= item.max) {
                    rate = type == 1 ? item.accuFund : item.bizLoan;
                    break;
                }
            }
            return rate;
        };

        //获取月利率 类型(1公积金 2商贷)、期数、选中的利率标准
        var getRate = function (type, year, rateIndex) {
            return obj.getRate(type, year, rateIndex) / 12;
        };

        //本金还款的月还款额(参数: 年利率 / 贷款总额 / 贷款总月份 / 贷款当前月0～length-1)
        var getMonthPayForInterest = function (lilv, total, month, cur_month) {
            // var lilv_month = lilv / 12; //月利率 //return total * lilv_month * Math.pow(1 + lilv_month, month) / ( Math.pow(1 + lilv_month, month) -1 );
            var benjin_money = total / month;
            return (total - benjin_money * cur_month) * lilv + benjin_money;
        }

        //本息还款的月还款额(参数: 年利率/贷款总额/贷款总月份)
        var getMonthPayForPrincipal = function (lilv, total, month) {
            //var lilv_month = lilv / 12;//月利率
            return total * lilv * Math.pow(1 + lilv, month) / (Math.pow(1 + lilv, month) - 1);
        }

        //装载利率
        var rateLoad = function (title, start, end, items) {
            var temps = new Array();
            for (var i = 0; i < items.length; i++) {
                temps.push({ min: items[i][0], max: items[i][1], bizLoan: items[i][2], accuFund: items[i][3] });
            }

            obj.rate.push({
                title: title,
                start: start,
                end: end,
                items: temps
            });
        };

        //初始化
        var init = function () {
	     rateLoad('2015.08.26基准利率', 20150826, 0, [[0, 1, 0.046, 0.0275], [1, 5, 0.05, 0.0275], [5, 30, 0.0515, 0.0325]]);
            rateLoad('2015.06.28基准利率', 20150628, 0, [[0, 1, 0.0485, 0.03], [1, 5, 0.0525, 0.03], [5, 30, 0.054, 0.035]]);
            rateLoad('2015.05.11基准利率', 20150511, 0, [[0, 1, 0.051, 0.0325], [1, 5, 0.055, 0.0325], [5, 30, 0.0565, 0.0375]]);
            rateLoad('2015.03.01基准利率', 20150301, 0, [[0, 1, 0.0535, 0.035], [1, 5, 0.0575, 0.035], [5, 30, 0.059, 0.04]]);
            rateLoad('2015.08.26利率下限（7折）', 20150826, 0, [[0, 1, 0.0322, 0.0193], [1, 5, 0.035, 0.0193], [5, 30, 0.0361, 0.0228]]);
            rateLoad('2015.06.28利率下限（7折）', 20150628, 0, [[0, 1, 0.034, 0.021], [1, 5, 0.0368, 0.021], [5, 30, 0.0378, 0.0245]]);
            rateLoad('2015.05.11利率下限（7折）', 20150511, 0, [[0, 1, 0.0357, 0.0228], [1, 5, 0.0385, 0.0228], [5, 30, 0.0396, 0.0263]]);
            rateLoad('2015.03.01利率下限（7折）', 20150301, 0, [[0, 1, 0.0374, 0.0245], [1, 5, 0.0403, 0.0245], [5, 30, 0.0413, 0.028]]);
            rateLoad('2015.08.26利率下限（85折）', 20150826, 0, [[0, 1, 0.0391, 0.0234], [1, 5, 0.0425, 0.0234], [5, 30, 0.0438, 0.0376]]);
            rateLoad('2015.06.28利率下限（85折）', 20150628, 0, [[0, 1, 0.0412, 0.0225], [1, 5, 0.0446, 0.0225], [5, 30, 0.0459, 0.0297]]);
            rateLoad('2015.05.11利率下限（85折）', 20150511, 0, [[0, 1, 0.0434, 0.0276], [1, 5, 0.0468, 0.0276], [5, 30, 0.048, 0.0319]]);
            rateLoad('2015.03.01利率下限（85折）', 20150301, 0, [[0, 1, 0.0455, 0.0297], [1, 5, 0.0489, 0.0297], [5, 30, 0.0501, 0.034]]);
            rateLoad('2015.08.26利率上限（1.1倍）', 20150826, 0, [[0, 1, 0.0506, 0.0303], [1, 5, 0.055, 0.0303], [5, 30, 0.0567, 0.0358]]);
            rateLoad('2015.06.28利率上限（1.1倍）', 20150628, 0, [[0, 1, 0.0534, 0.033], [1, 5, 0.0578, 0.033], [5, 30, 0.0594, 0.0385]]);
            rateLoad('2015.05.11利率上限（1.1倍）', 20150511, 0, [[0, 1, 0.0561, 0.0358], [1, 5, 0.0605, 0.0358], [5, 30, 0.0622, 0.0413]]);
            rateLoad('2015.03.01利率上限（1.1倍）', 20150301, 0, [[0, 1, 0.0589, 0.0385], [1, 5, 0.0633, 0.0385], [5, 30, 0.0649, 0.044]]);

            rateLoad('2014.11.22首套房优惠(15%)利率', 20141122, 0, [[0, 1, 0.0476, 0.0375], [1, 5, 0.051, 0.0375], [5, 30, 0.052275, 0.0425]]);
            rateLoad('2014.11.22基准利率', 20141122, 0, [[0, 1, 0.056, 0.0375], [1, 5, 0.06, 0.0375], [5, 30, 0.0615, 0.0425]]);
            rateLoad('2014.11.22第二套房上浮(10%)利率', 20141122, 0, [[0, 1, 0.0616, 0.0375], [1, 5, 0.066, 0.0375], [5, 30, 0.06765, 0.0425]]);
        };

        init();
    };
})(jQuery);