first commit

6 files changed, 428 insertions, 0 deletions

diff --git a/customer/controller.go b/customer/controller.go
new file mode 100644
index 0000000..9381c45
--- /dev/null
+++ b/customer/controller.go
@@ -0,0 +1,102 @@
+/* openbills - Server for web based Libre Billing Software
+ * Copyright (C) 2023  Vidhu Kant Sharma <vidhukant@vidhukant.com>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package customer
+
+import (
+	e "vidhukant.com/openbills/errors"
+	"github.com/gin-gonic/gin"
+	"net/http"
+	"strconv"
+)
+
+func handleGetSingleCustomer (ctx *gin.Context) {
+	id, err := strconv.ParseUint(ctx.Param("id"), 10, 64)
+	if err != nil {
+		ctx.Error(e.ErrInvalidID)
+		return
+	}
+
+	var customer Customer
+
+	err = getCustomer(&customer, uint(id))
+	if err != nil {
+		ctx.Error(err)
+		ctx.Abort()
+		return
+	}
+
+	ctx.JSON(http.StatusOK, gin.H{
+		"message": "success",
+		"data": customer,
+	})
+}
+
+func handleGetCustomers (ctx *gin.Context) {
+	var customers []Customer
+
+	err := getCustomers(&customers)
+	if err != nil {
+		ctx.Error(err)
+		ctx.Abort()
+		return
+	}
+
+	ctx.JSON(http.StatusOK, gin.H{
+		"message": "success",
+		"data": customers,
+	})
+}
+
+func handleSaveCustomer (ctx *gin.Context) {
+	var customer Customer
+	ctx.Bind(&customer)
+
+	err := customer.upsert()
+	if err != nil {
+		ctx.Error(err)
+		ctx.Abort()
+		return
+	}
+
+	ctx.JSON(http.StatusOK, gin.H{
+		"message": "success",
+		"data": customer,
+	})
+}
+
+func handleDelCustomer (ctx *gin.Context) {
+	id, err := strconv.ParseUint(ctx.Param("id"), 10, 64)
+	if err != nil {
+		ctx.Error(e.ErrInvalidID)
+		return
+	}
+
+	var customer Customer
+	customer.ID = uint(id)
+
+	err = customer.del()
+	if err != nil {
+		ctx.Error(err)
+		ctx.Abort()
+		return
+	}
+
+	ctx.JSON(http.StatusOK, gin.H{
+		"message": "success",
+	})
+}
diff --git a/customer/customer.go b/customer/customer.go
new file mode 100644
index 0000000..5f25e2d
--- /dev/null
+++ b/customer/customer.go
@@ -0,0 +1,66 @@
+/* openbills - Server for web based Libre Billing Software
+ * Copyright (C) 2023  Vidhu Kant Sharma <vidhukant@vidhukant.com>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package customer
+
+import (
+	"gorm.io/gorm"
+	d "vidhukant.com/openbills/db"
+)
+
+var db *gorm.DB
+func init() {
+	db = d.DB
+
+	db.AutoMigrate(&Customer{}, &CustomerContact{}, &CustomerBillingAddress{}, &CustomerShippingAddress{})
+}
+
+type CustomerContact struct {
+	gorm.Model
+	CustomerID uint
+	Name       string
+	Phone      string
+	Email      string
+	Website    string
+}
+
+type Address struct {
+	AddressText string
+	City        string
+	State       string
+	PostalCode  string
+	Country     string
+}
+
+type CustomerBillingAddress struct {
+	Address
+	CustomerID  uint
+}
+
+type CustomerShippingAddress struct {
+	Address
+	CustomerID  uint
+}
+
+type Customer struct {
+	gorm.Model
+	Name              string
+	Gstin             string 
+	Contact           CustomerContact
+	BillingAddress    CustomerBillingAddress
+	ShippingAddresses []CustomerShippingAddress
+}
diff --git a/customer/hooks.go b/customer/hooks.go
new file mode 100644
index 0000000..020e1c5
--- /dev/null
+++ b/customer/hooks.go
@@ -0,0 +1,48 @@
+/* openbills - Server for web based Libre Billing Software
+ * Copyright (C) 2023  Vidhu Kant Sharma <vidhukant@vidhukant.com>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package customer
+
+import (
+	"gorm.io/gorm"
+	"vidhukant.com/openbills/errors"
+)
+
+func (c *Customer) BeforeSave(tx *gorm.DB) error {
+	var err error
+
+	err = c.validate()
+	if err != nil {
+		return err
+	}
+
+	err = c.Contact.validate()
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func (c *Customer) BeforeDelete(tx *gorm.DB) error {
+  // if ID is 0, customer won't be deleted
+	if c.ID == 0 {
+		return errors.ErrNoWhereCondition
+	}
+
+	return nil
+}
diff --git a/customer/router.go b/customer/router.go
new file mode 100644
index 0000000..9db92d3
--- /dev/null
+++ b/customer/router.go
@@ -0,0 +1,32 @@
+/* openbills - Server for web based Libre Billing Software
+ * Copyright (C) 2023  Vidhu Kant Sharma <vidhukant@vidhukant.com>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package customer
+
+import (
+	"github.com/gin-gonic/gin"
+)
+
+func Routes(route *gin.RouterGroup) {
+	g := route.Group("/customer")
+	{
+		g.GET("/", handleGetCustomers)
+		g.GET("/:id", handleGetSingleCustomer)
+		g.POST("/", handleSaveCustomer)
+		g.DELETE("/:id", handleDelCustomer)
+	}
+}
diff --git a/customer/service.go b/customer/service.go
new file mode 100644
index 0000000..c5d7cb8
--- /dev/null
+++ b/customer/service.go
@@ -0,0 +1,73 @@
+/* openbills - Server for web based Libre Billing Software
+ * Copyright (C) 2023  Vidhu Kant Sharma <vidhukant@vidhukant.com>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package customer
+
+import (
+	e "vidhukant.com/openbills/errors"
+)
+
+func getCustomer(customer *Customer, id uint) error {
+	res := db.Preload("Contact").Preload("BillingAddress").Preload("ShippingAddresses").Find(&customer, id)
+
+	// TODO: handle potential errors
+	if res.Error != nil {
+		return res.Error
+	}
+
+	if res.RowsAffected == 0 {
+		return e.ErrNotFound
+	}
+
+	return nil
+}
+
+func getCustomers(customers *[]Customer) error {
+	res := db.Find(&customers)
+
+	// TODO: handle potential errors
+	if res.Error != nil {
+		return res.Error
+	}
+
+	if res.RowsAffected == 0 {
+		return e.ErrEmptyResponse
+	}
+
+	return nil
+}
+
+func (c *Customer) upsert() error {
+	res := db.Save(c)
+	// TODO: handle potential errors
+	return res.Error
+}
+
+func (c *Customer) del() error {
+	res := db.Delete(c)
+
+	// TODO: handle potential errors
+	if res.Error != nil {
+		return res.Error
+	}
+
+	if res.RowsAffected == 0 {
+		return e.ErrNotFound
+	}
+
+	return nil
+}
diff --git a/customer/validators.go b/customer/validators.go
new file mode 100644
index 0000000..6c51ad9
--- /dev/null
+++ b/customer/validators.go
@@ -0,0 +1,107 @@
+/* openbills - Server for web based Libre Billing Software
+ * Copyright (C) 2023  Vidhu Kant Sharma <vidhukant@vidhukant.com>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package customer
+
+import (
+	"regexp"
+	"strings"
+	"vidhukant.com/openbills/errors"
+	e "errors"
+)
+
+// NOTE: very inefficient and really really really dumb but it works
+// TODO: find a better (or even a remotely good) way
+func validateContactField(field, value string) error {
+	if value != "" {
+		var count int64
+		err := db.Model(&CustomerContact{}).
+			Where(field + " = ?", value).
+			Count(&count).
+			Error
+
+		if err != nil {
+			return err
+		}
+
+		if count > 0 {
+			switch(field) {
+			case "phone":
+				return errors.ErrNonUniquePhone
+			case "email":
+				return errors.ErrNonUniqueEmail
+			case "website":
+				return errors.ErrNonUniqueWebsite
+			default:
+				return e.New(field + " is not unique")
+			}
+		}
+	}
+
+	return nil
+}
+
+func (c *CustomerContact) validate() error {
+	// trim whitespaces
+	c.Name = strings.TrimSpace(c.Name)
+	c.Phone = strings.TrimSpace(c.Phone)
+	c.Email = strings.TrimSpace(c.Email)
+	c.Website = strings.TrimSpace(c.Website)
+
+	var err error
+	for _, i := range [][]string{{"phone", c.Phone}, {"email", c.Email}, {"website", c.Website}} {
+		err = validateContactField(i[0], i[1])
+		if err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+func (c *Customer) validate() error {
+	// trim whitespaces
+	c.Name = strings.TrimSpace(c.Name)
+	c.Gstin = strings.TrimSpace(c.Gstin)
+
+	// don't validate if GSTIN is empty
+	if c.Gstin != "" {
+	  // GSTIN regex validation
+		match, _ := regexp.MatchString("^[0-9]{2}[A-Z]{5}[0-9]{4}[A-Z]{1}[1-9A-Z]{1}Z[0-9A-Z]{1}$", c.Gstin)
+		if (!match) {
+			return errors.ErrInvalidGSTIN
+		}
+
+		// make sure GSTIN is unique
+		var count int64
+		err := db.Model(&Customer{}).
+			Select("gstin").
+			Where("gstin = ?", c.Gstin).
+			Count(&count).
+			Error
+
+		if err != nil {
+			return err
+		}
+
+		if count > 0 {
+			return errors.ErrNonUniqueGSTIN
+		}
+	}
+
+	return nil
+}