Adds seed script

cmd/seed/main.go

@@ -0,0 +1,224 @@
+package main
+
+import (
+	"fmt"
+	"log"
+	"math/rand"
+	"os"
+	"strconv"
+	"time"
+
+	"erp_system/internal/database"
+
+	_ "modernc.org/sqlite"
+)
+
+func main() {
+	dbPath := "erp.db"
+	if len(os.Args) > 1 {
+		dbPath = os.Args[1]
+	}
+
+	log.Printf("Connecting to database at %s...", dbPath)
+	// We can use the internal database package to initialize (runs migrations)
+	db, err := database.Initialize(dbPath)
+	if err != nil {
+		log.Fatalf("Failed to initialize database: %v", err)
+	}
+	defer db.Close()
+
+	// Configuration for generation
+	const (
+		numCustomers      = 500
+		maxOrdersPerCust  = 15
+		maxLinesPerOrder  = 8
+		numJournalEntries = 100
+	)
+
+	log.Println("Starting data generation...")
+	start := time.Now()
+
+	tx, err := db.Begin()
+	if err != nil {
+		log.Fatalf("Failed to begin transaction: %v", err)
+	}
+
+	// 1. Customers
+	customerIDs := make([]int64, 0, numCustomers)
+	for i := 0; i < numCustomers; i++ {
+		name := fmt.Sprintf("Customer %s %s", randomString(5), randomString(7))
+		email := fmt.Sprintf("%s.%s@example.com", randomString(4), randomString(5))
+		phone := fmt.Sprintf("555-%04d", rand.Intn(10000))
+		address := fmt.Sprintf("%d %s St, City %s", rand.Intn(999), randomString(6), randomString(4))
+
+		res, err := tx.Exec("INSERT INTO customers (name, email, phone, address) VALUES (?, ?, ?, ?)", name, email, phone, address)
+		if err != nil {
+			tx.Rollback()
+			log.Fatalf("Failed to insert customer: %v", err)
+		}
+		id, _ := res.LastInsertId()
+		customerIDs = append(customerIDs, id)
+	}
+	log.Printf("Generated %d customers", numCustomers)
+
+	// 2. Orders and Lines and Invoices
+	var orderCount, lineCount, invoiceCount int
+	for _, custID := range customerIDs {
+		numOrders := rand.Intn(maxOrdersPerCust)
+		for j := 0; j < numOrders; j++ {
+			// Create Order
+			status := "draft"
+			r := rand.Float32()
+			if r > 0.7 {
+				status = "fulfilled"
+			} else if r > 0.4 {
+				status = "confirmed"
+			} else if r > 0.3 {
+				status = "cancelled"
+			}
+
+			// Random date in last year
+			orderDate := time.Now().AddDate(0, 0, -rand.Intn(365))
+
+			res, err := tx.Exec("INSERT INTO orders (customer_id, status, order_date, notes) VALUES (?, ?, ?, ?)",
+				custID, status, orderDate.Format("2006-01-02"), "Generated order")
+			if err != nil {
+				tx.Rollback()
+				log.Fatalf("Failed to insert order: %v", err)
+			}
+			orderID, _ := res.LastInsertId()
+			orderCount++
+
+			// Create Order Lines
+			numLines := rand.Intn(maxLinesPerOrder) + 1
+			var totalAmount float64
+			for k := 0; k < numLines; k++ {
+				qty := float64(rand.Intn(10) + 1)
+				price := float64(rand.Intn(100) + 10)
+				desc := fmt.Sprintf("Product %s-%d", randomString(3), rand.Intn(100))
+				lineTotal := qty * price
+				totalAmount += lineTotal
+
+				_, err := tx.Exec("INSERT INTO order_lines (order_id, description, quantity, unit_price, line_total) VALUES (?, ?, ?, ?, ?)",
+					orderID, desc, qty, price, lineTotal)
+				if err != nil {
+					tx.Rollback()
+					log.Fatalf("Failed to insert order line: %v", err)
+				}
+				lineCount++
+			}
+
+			// Update Order Total
+			_, err = tx.Exec("UPDATE orders SET total_amount = ? WHERE id = ?", totalAmount, orderID)
+			if err != nil {
+				tx.Rollback()
+				log.Fatalf("Failed to update order total: %v", err)
+			}
+
+			// Create Invoice if order is confirmed or fulfilled
+			if status == "confirmed" || status == "fulfilled" {
+				invoiceStatus := "pending"
+				if rand.Float32() > 0.5 {
+					invoiceStatus = "paid"
+				}
+
+				invNum := fmt.Sprintf("INV-%d-%d", orderID, rand.Intn(10000))
+				dueDate := orderDate.AddDate(0, 1, 0) // Due in 30 days
+				var paidDate interface{} = nil
+				if invoiceStatus == "paid" {
+					pd := dueDate.AddDate(0, 0, -rand.Intn(10))
+					paidDate = pd.Format("2006-01-02")
+				}
+
+				_, err := tx.Exec("INSERT INTO invoices (order_id, customer_id, invoice_number, status, amount, due_date, paid_date) VALUES (?, ?, ?, ?, ?, ?, ?)",
+					orderID, custID, invNum, invoiceStatus, totalAmount, dueDate.Format("2006-01-02"), paidDate)
+				if err != nil {
+					tx.Rollback()
+					log.Fatalf("Failed to insert invoice: %v", err)
+				}
+				invoiceCount++
+			}
+		}
+	}
+	log.Printf("Generated %d orders, %d lines, %d invoices", orderCount, lineCount, invoiceCount)
+
+	// 3. Journal Entries
+	// Fetch account IDs first
+	rows, err := tx.Query("SELECT id, code, type FROM gl_accounts")
+	if err != nil {
+		tx.Rollback()
+		log.Fatalf("Failed to fetch accounts: %v", err)
+	}
+	defer rows.Close()
+
+	type Account struct {
+		ID   int64
+		Code string
+		Type string
+	}
+	var accounts []Account
+	for rows.Next() {
+		var a Account
+		if err := rows.Scan(&a.ID, &a.Code, &a.Type); err != nil {
+			log.Fatalf("Failed to scan account: %v", err)
+		}
+		accounts = append(accounts, a)
+	}
+
+	if len(accounts) >= 2 {
+		for i := 0; i < numJournalEntries; i++ {
+			date := time.Now().AddDate(0, 0, -rand.Intn(60)).Format("2006-01-02")
+			desc := fmt.Sprintf("Journal Entry %d", i+1)
+
+			res, err := tx.Exec("INSERT INTO journal_entries (entry_date, description, reference) VALUES (?, ?, ?)",
+				date, desc, "GEN-"+strconv.Itoa(i))
+			if err != nil {
+				tx.Rollback()
+				log.Fatalf("Failed to insert journal entry: %v", err)
+			}
+			jeID, _ := res.LastInsertId()
+
+			// Simple balanced entry: 2 lines
+			amount := float64(rand.Intn(5000) + 100)
+
+			// Pick 2 random accounts
+			idx1 := rand.Intn(len(accounts))
+			idx2 := rand.Intn(len(accounts))
+			for idx1 == idx2 {
+				idx2 = rand.Intn(len(accounts))
+			}
+
+			// Debit line
+			_, err = tx.Exec("INSERT INTO journal_lines (journal_entry_id, account_id, debit, credit) VALUES (?, ?, ?, ?)",
+				jeID, accounts[idx1].ID, amount, 0)
+			if err != nil {
+				tx.Rollback()
+				log.Fatalf("Failed to insert journal line 1: %v", err)
+			}
+
+			// Credit line
+			_, err = tx.Exec("INSERT INTO journal_lines (journal_entry_id, account_id, debit, credit) VALUES (?, ?, ?, ?)",
+				jeID, accounts[idx2].ID, 0, amount)
+			if err != nil {
+				tx.Rollback()
+				log.Fatalf("Failed to insert journal line 2: %v", err)
+			}
+		}
+	}
+	log.Printf("Generated %d journal entries", numJournalEntries)
+
+	if err := tx.Commit(); err != nil {
+		log.Fatalf("Failed to commit transaction: %v", err)
+	}
+
+	log.Printf("Seeding completed in %v", time.Since(start))
+}
+
+func randomString(n int) string {
+	var letters = []rune("abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ")
+	b := make([]rune, n)
+	for i := range b {
+		b[i] = letters[rand.Intn(len(letters))]
+	}
+	return string(b)
+}