import { v4 as uuidv4 } from 'uuid';
import { bignumber, chain } from 'mathjs';
import { InvoiceControllerState, LineAttributeType } from '../';
import idGenerator from '../../tools/idGenerator';

export interface IOptions {
    /** 需要添加的索引 */
    $index: string;

    /** 折扣 金额 */
    discolineAmountunt: number;
}

/**
 * 给一组货物添加折扣行
 */
export default async (state: InvoiceControllerState, options?: IOptions[]) => {

    if (!options || options.length <= 0) return;

    const discountGroup = uuidv4();

    options.forEach(e => {
        const goodsList = state.goodsListState.goodsList;
        const goodsMap = state.goodsListState.goodsMap;
        for (let i = 0; i < goodsList.length; i++) {
            const good = goodsList[i];
            if (good.$index !== e.$index) continue;

            // 折扣行 税额
            const lineAmountExcludeTax = getLineAmountExcludeTax(e.discolineAmountunt, good.taxRate);
            const taxAmount = getTaxAmount(e.discolineAmountunt, lineAmountExcludeTax);

            good.lineAttribute = LineAttributeType.被折扣行;
            good.discountGroup = discountGroup;

            const newGood = {
                discountGroup,
                $index: idGenerator(),
                lineAttribute: LineAttributeType.折扣行,
                taxRate: good.taxRate,
                itemName: good.itemName,
                shorthand: good.shorthand,
                taxClassificationCode: good.taxClassificationCode,

                taxAmount: -1 * taxAmount,
                lineAmountExcludeTax: -1 * lineAmountExcludeTax,
                lineAmountIncludeTax: -1 * e.discolineAmountunt,

                taxFreeType: good.taxFreeType,
                favouredPolicyMark: good.favouredPolicyMark,
                favouredPolicyName: good.favouredPolicyName,
            }

            goodsList.splice(i + 1, 0, newGood);
            goodsMap.set(newGood.$index, newGood);
        }
    })

    state.goodsListState.goodsList = [...state.goodsListState.goodsList];
    state.goodsListState.goodsMap = new Map(state.goodsListState.goodsMap);
}

/** 金额（不含税） = 含税金额 / (1 + 税率) */
function getLineAmountExcludeTax(lineAmountIncludeTax: number, taxRate: number = 0) {
    const biTaxRate = chain(bignumber(taxRate)).divide(bignumber(100)).done();
    return chain(bignumber(lineAmountIncludeTax))
        .divide(chain(bignumber(1)).add(biTaxRate).done())

        .multiply(bignumber(100))
        .round()
        .divide(bignumber(100))

        .done()
        .toNumber()
}

/** 税额 = 含税金额 - 金额（不含税） */
function getTaxAmount(lineAmountIncludeTax: number, lineAmountExcludeTax: number) {
    return chain(bignumber(lineAmountIncludeTax))
        .subtract(bignumber(lineAmountExcludeTax))

        .done()
        .toNumber()
}