xavierk
a00c816635
issue_invoice allocates the number, freezes vendor and bank details and stores server-computed totals in one transaction. Issued invoices are cancelled, not deleted. Tax heads derive from supplier state and place of supply (a disagreeing choice is rejected); unregistered suppliers issue a plain Invoice. Adds GSTIN checksum validation, canonical India Compliance state list, server-side drafts, series validation, relative and magic-byte-checked asset paths, and GST settings. PDF re-exports use the frozen vendor snapshot.
67 lines
1.9 KiB
TypeScript
67 lines
1.9 KiB
TypeScript
import type { InvoiceItem, TaxType } from "./types";
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// The preview must show exactly what Rust stores (src-tauri/src/gst.rs), so money is
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// computed in integer paise with round-half-up, the same way.
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const toPaise = (rupees: number) => Math.round((Number.isFinite(rupees) ? rupees : 0) * 100);
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function linePaise(item: InvoiceItem): number {
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if (item.mode === "rate") {
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return Math.round(toPaise(item.rate || 0) * (item.quantity || 0));
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}
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return toPaise(item.amount || 0);
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}
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/** Round-half-up division for non-negative integers. */
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const divRound = (num: number, den: number) => Math.floor((num + den / 2) / den);
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/** Amount for a single line: a fixed total, or rate × quantity. */
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export function computeLineAmount(item: InvoiceItem): number {
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return linePaise(item) / 100;
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}
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export interface Totals {
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subtotal: number;
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discount: number;
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taxable: number;
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cgst: number;
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sgst: number;
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igst: number;
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taxTotal: number;
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total: number;
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}
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export function computeTotals(
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items: InvoiceItem[],
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discount: number,
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taxType: TaxType,
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taxRate: number,
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): Totals {
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const subtotal = items.reduce((sum, item) => sum + linePaise(item), 0);
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const discountPaise = Math.min(Math.max(toPaise(discount), 0), Math.max(subtotal, 0));
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const taxable = subtotal - discountPaise;
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const rateBp = Math.round((Number.isFinite(taxRate) ? taxRate : 0) * 100);
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let cgst = 0;
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let sgst = 0;
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let igst = 0;
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if (taxType === "cgst_sgst") {
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cgst = divRound(taxable * rateBp, 20_000);
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sgst = cgst;
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} else if (taxType === "igst") {
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igst = divRound(taxable * rateBp, 10_000);
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}
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const taxTotal = cgst + sgst + igst;
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return {
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subtotal: subtotal / 100,
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discount: discountPaise / 100,
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taxable: taxable / 100,
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cgst: cgst / 100,
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sgst: sgst / 100,
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igst: igst / 100,
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taxTotal: taxTotal / 100,
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total: (taxable + taxTotal) / 100,
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};
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}
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