import { createContext, DomainError } from "@tailor-platform/erp-kit/app";
import { createResolver, t } from "@tailor-platform/sdk";
import { getDB } from "@/generated/kysely-tailordb";
import { finModulesExport } from "@/modules";

/**
 * reverseJournalEntry — reverse a POSTED journal entry.
 *
 * Thin wrapper over the native `reverseJournalEntry`. Creates a new POSTED entry
 * whose debits/credits mirror the original (the only correction mechanism for a
 * posted entry). The original stays POSTED for traceability. The reversal posts
 * to the original period unless `reversalPeriodId` is given, and that target
 * period must be OPEN.
 */
export default createResolver({
  name: "reverseJournalEntry",
  operation: "mutation",
  input: {
    id: t.string().description("Original (POSTED) journal entry ID"),
    reversalPeriodId: t
      .string({ optional: true })
      .description("Accounting period for the reversal; defaults to the original entry's period"),
  },
  body: async (context) => {
    const ctx = createContext(context);
    const db = getDB("main-db");
    return db
      .transaction()
      .execute(async (trx) => {
        const result = await finModulesExport.commands.reverseJournalEntry(
          trx,
          {
            id: context.input.id,
            reversalPeriodId: context.input.reversalPeriodId ?? undefined,
          },
          ctx,
        );

        if (!result.ok) {
          switch (result.error.code) {
            case "FINANCIAL_ACCOUNTING_JOURNAL_ENTRY_NOT_FOUND":
              throw new DomainError(`Journal entry not found: ${context.input.id}`);
            case "FINANCIAL_ACCOUNTING_INVALID_STATUS_FOR_REVERSAL":
              throw new DomainError("Only a POSTED journal entry can be reversed.");
            case "FINANCIAL_ACCOUNTING_ALREADY_REVERSED":
              throw new DomainError("This journal entry has already been reversed.");
            case "FINANCIAL_ACCOUNTING_INVALID_PERIOD_STATUS":
              throw new DomainError("The reversal's accounting period is not OPEN.");
            case "UNAUTHENTICATED":
              throw new DomainError("Authentication is required");
            case "INSUFFICIENT_PERMISSION":
              throw new DomainError("You do not have permission to perform this action");
            default:
              throw result.error satisfies never;
          }
        }

        return {
          id: result.value.reversalEntry.id,
          status: result.value.reversalEntry.status,
          originalId: result.value.originalEntry.id,
        };
      })
      .catch((err: unknown) => {
        if (err instanceof DomainError) throw err;
        throw new Error("Failed to reverse the journal entry", { cause: err });
      });
  },
  output: t
    .object({
      id: t.string().description("Reversal journal entry ID"),
      status: t.string().description("Reversal document status (POSTED)"),
      originalId: t.string().description("The original (reversed) journal entry ID"),
    })
    .description("ReverseJournalEntry response"),
});