feat: 增值税计算,sql构建完成 (#527)

Reviewed-on: daoyoucloud/tachycode#527
Co-authored-by: bai.jingfeng <bai.jingfeng@foxmail.com>
Co-committed-by: bai.jingfeng <bai.jingfeng@foxmail.com>

packages/plugins/@hera/plugin-rental/src/server/sqls/view_invoices_tax.sql

@@ -0,0 +1,223 @@
+-- CREATE OR REPLACE VIEW
+--   public.view_invoice_tax AS
+-- 第一步-NO.1: 发票进项表和完税凭证表: 
+-- 输入: invoice_input, invoice_receipt
+-- 1. 筛选所需字段并统一命名
+-- 2. 将发票进项表和完税凭证表, 两个表的数据合并
+-- 输出: A_INPUT
+WITH RECURSIVE
+  A_INPUT AS (
+    SELECT
+      purchaser_id AS company_id, -- 发票进项取购买方公司id,作为本公司id标识
+      authentication_date AS "date", -- 发票进项取认证日期,作为计算月份的来源
+      tax_amount
+    FROM
+      invoice_input
+    UNION ALL
+    SELECT
+      purchaser_id AS company_id, -- 完税凭证,同发票进项字段
+      authentication_date AS "date", -- 完税凭证,同发票进项字段
+      tax_amount
+    FROM
+      invoice_receipt
+  ),
+  -- 第一步-NO.2:发票销项表: 
+  -- 输入: invoice_output
+  -- 1. 筛选所需字段并统一命名
+  -- 输出: A_OUTPUT
+  A_OUTPUT AS (
+    SELECT
+      seller_id AS company_id, -- 发票销项取销售方id,作为本公司id标识
+      "Invoicing_date" AS "date", -- 发票销项取开票日期,作为计算月份的来源
+      tax_amount
+    FROM
+      invoice_output
+  ),
+  -- 第二步-NO.1: 聚合发票进项表: 
+  -- 输入: A_INPUT
+  -- 1. 筛选出日期在'2022-01-01'之后的数据
+  -- 2. 按照 company_id 和 date 聚合计算后的月份 "MONTH"
+  -- 3. 获取对应月份的进项税额 input_tax_amount
+  -- 输出: B_INPUT
+  B_INPUT AS (
+    SELECT
+      company_id,
+      DATE_TRUNC('month', "date") AS "MONTH",
+      COALESCE(SUM(tax_amount), 0) AS input_tax_amount
+    FROM
+      A_INPUT
+    WHERE
+      "date" >= '2022-01-01'
+    GROUP BY
+      company_id,
+      "MONTH"
+  ),
+  -- 第二步-NO.2: 聚合B_OUTPUT: 
+  -- 输入: A_OUTPUT
+  -- 1. 筛选出日期在'2022-01-01'之后的数据
+  -- 2. 按照 company_id 和 date 聚合计算后的月份 "MONTH"
+  -- 3. 获取对应月份的销项税额 output_tax_amount
+  -- 输出: B_OUTPUT
+  B_OUTPUT AS (
+    SELECT
+      company_id,
+      DATE_TRUNC('month', "date") AS "MONTH",
+      COALESCE(SUM(tax_amount), 0) AS out_tax_amount
+    FROM
+      A_OUTPUT
+    WHERE
+      "date" >= '2022-01-01'
+    GROUP BY
+      company_id,
+      "MONTH"
+  ),
+  -- 第三步: JOIN 两个表,B_INPUT, B_OUTPUT: 
+  -- 1. 聚合两个表,保留全部记录
+  -- 2. 聚合后的表,如果某个表的对应取值字段为null,则置为0
+  -- 输入: B_INPUT, B_OUTPUT
+  -- 输出: C_INTIAL_TAX
+  C_INTIAL_TAX AS (
+    SELECT
+      COALESCE(B_INPUT.company_id, B_OUTPUT.company_id) AS company_id,
+      COALESCE(B_INPUT."MONTH", B_OUTPUT."MONTH") AS "MONTH",
+      COALESCE(B_INPUT.input_tax_amount, 0) AS input_tax_amount,
+      COALESCE(B_OUTPUT.out_tax_amount, 0) AS out_tax_amount
+    FROM
+      B_INPUT
+      FULL JOIN B_OUTPUT ON B_INPUT.company_id = B_OUTPUT.company_id
+      AND B_INPUT."MONTH" = B_OUTPUT."MONTH"
+  ),
+  -- 第4步: JOIN 两个表,B_INPUT, B_OUTPUT: 
+  -- 1. 聚合两个表,保留全部记录
+  -- 2. 聚合后的表,如果某个表的对应取值字段为null,则置为0
+  -- 输入: B_INPUT, B_OUTPUT
+  -- 输出: C_INTIAL_TAX
+  D_INTIAL_TAX AS (
+    SELECT
+      company_id,
+      "MONTH",
+      input_tax_amount,
+      out_tax_amount,
+      input_tax_amount - out_tax_amount AS excessive_tax_amount
+    FROM
+      C_INTIAL_TAX
+    ORDER BY
+      company_id,
+      "MONTH"
+  ),
+  E_INTIAL_TAX AS (
+    SELECT
+      company_id,
+      "MONTH",
+      input_tax_amount,
+      out_tax_amount,
+      excessive_tax_amount,
+      ROW_NUMBER() OVER (
+        PARTITION BY
+          company_id
+        ORDER BY
+          company_id,
+          "MONTH"
+      ) AS row_num
+    FROM
+      D_INTIAL_TAX
+    ORDER BY
+      company_id,
+      "MONTH"
+  ),
+  -- 第四步: 定义一个递归来根据上一个应缴税额,计算当前的应缴税额
+  F_INTIAL_TAX AS (
+    -- 初始查询部分
+    (
+      SELECT
+        row_num,
+        company_id,
+        "MONTH",
+        input_tax_amount,
+        out_tax_amount,
+        excessive_tax_amount,
+        -- 当前应缴税额的初始值 
+        (
+          COALESCE(
+            (
+              SELECT
+                intial_value
+              FROM
+                invoice_tax_intial
+              WHERE
+                invoice_tax_intial.company_id = E_INTIAL_TAX.company_id
+            ),
+            0
+          ) + excessive_tax_amount
+        ) AS monthly_tax_amount
+      FROM
+        E_INTIAL_TAX
+      WHERE
+        row_num = 1
+    )
+    UNION ALL
+    -- 递归查询部分
+    (
+      SELECT
+        curr.row_num,
+        curr.company_id,
+        curr."MONTH",
+        curr.input_tax_amount,
+        curr.out_tax_amount,
+        curr.excessive_tax_amount,
+        (
+          CASE
+            WHEN prev.monthly_tax_amount <= 0
+            -- 如果上一条 monthly_tax_amount 是负数, 代表上月交出税
+            THEN curr.excessive_tax_amount
+            -- 如果上一条 monthly_tax_amount 是正数, 代表上月有结余
+            ELSE curr.excessive_tax_amount + prev.monthly_tax_amount
+          END
+        ) AS monthly_tax_amount
+      FROM
+        E_INTIAL_TAX AS curr
+        -- 连接当前行和前一行
+        JOIN F_INTIAL_TAX AS prev ON (
+          curr.company_id = prev.company_id
+          AND curr.row_num = prev.row_num + 1
+        )
+    )
+  ),
+  -- 求附加税和合计税额
+  G_INTIAL_TAX AS (
+    SELECT
+      row_num,
+      company_id,
+      "MONTH",
+      input_tax_amount,
+      out_tax_amount,
+      monthly_tax_amount,
+      (
+        CASE
+          WHEN monthly_tax_amount < 0 THEN monthly_tax_amount * 0.12
+          ELSE 0
+        END
+      ) AS super_tax_amount,
+      (
+        CASE
+          WHEN monthly_tax_amount < 0 THEN monthly_tax_amount + monthly_tax_amount * 0.12
+          ELSE 0
+        END
+      ) AS monthly_total_tax_amount
+    FROM
+      F_INTIAL_TAX
+    ORDER BY
+      company_id,
+      "MONTH"
+  )
+  -- 主查询
+  -- 第五步: 根据计算后的表 D_FINAL_TAX,获取最终的视图
+  -- 输入: D_FINAL_TAX
+  -- 输出: 最终主查询视图, public.view_invoice_tax
+SELECT
+  *
+FROM
+  G_INTIAL_TAX
+ORDER BY
+  company_id,
+  "MONTH"