/**
 * tx-claim.test.ts — RED phase tests for buildClaimTx() (Open → Claimed)
 *
 * Tests mirror escrow.ak:handle_claim invariants:
 *   - signed by supplier_pkh
 *   - old state = Open
 *   - new datum state = Claimed, all other fields unchanged
 *   - value preserved
 *   - validity upper-bound ≤ deliver_by
 *   - redeemer is Claim (Constr index 0)
 *
 * Uses buyer-side fixture UTxOs for the "existing escrow" input.
 */

import { describe, it, expect, beforeEach } from "vitest";
import { MockChainProvider } from "../../packages/shared/src/chain/MockChainProvider.js";
import { buildClaimTx } from "../../packages/shared/src/tx/escrow/claim.js";
import { TxConstructionError } from "../../packages/shared/src/tx/types.js";
import { decodeEscrowDatum } from "../../packages/shared/src/cbor/EscrowDatum.js";
import { buildSupplierWalletKey } from "../fixtures/supplier-side/wallet-keys.js";
import { buildBuyerWalletKey } from "../fixtures/buyer-side/wallet-keys.js";
import {
  buildOpenEscrowUtxo,
  buildClaimedEscrowUtxo,
  DELIVER_BY,
  TOTAL_LOCKED,
} from "../fixtures/buyer-side/sample-escrow-utxos.js";

// ─── Happy path ───────────────────────────────────────────────────────────────

describe("buildClaimTx() — happy path", () => {
  let chain: MockChainProvider;

  beforeEach(() => {
    chain = new MockChainProvider();
    // Synthetic tip well before deliver_by
    chain.advanceSlot(Math.floor((DELIVER_BY - 100_000) / 1000));
    const utxo = buildOpenEscrowUtxo();
    chain.seed(utxo);
  });

  it("returns a non-empty txCborHex", async () => {
    const supplier = buildSupplierWalletKey();
    const utxo = buildOpenEscrowUtxo();
    const result = await buildClaimTx({ chain, supplierKey: supplier, escrowRef: utxo.ref });
    expect(typeof result.txCborHex).toBe("string");
    expect(result.txCborHex.length).toBeGreaterThan(0);
  });

  it("continuing output datum has state = Claimed", async () => {
    const supplier = buildSupplierWalletKey();
    const utxo = buildOpenEscrowUtxo();
    const result = await buildClaimTx({ chain, supplierKey: supplier, escrowRef: utxo.ref });
    // After claim, chain has the new UTxO at same address with Claimed state
    const txHash = result.expectedTxHash;
    const newUtxo = await chain.queryUtxo({ txHash, index: 0 });
    const datum = decodeEscrowDatum(newUtxo!.datumHex!);
    expect(datum.state).toBe("Claimed");
  });

  it("continuing output value equals locked value (preserved)", async () => {
    const supplier = buildSupplierWalletKey();
    const utxo = buildOpenEscrowUtxo();
    const result = await buildClaimTx({ chain, supplierKey: supplier, escrowRef: utxo.ref });
    const txHash = result.expectedTxHash;
    const newUtxo = await chain.queryUtxo({ txHash, index: 0 });
    expect(newUtxo!.lovelace).toBe(TOTAL_LOCKED);
  });

  it("continuing output datum fields other than state are unchanged", async () => {
    const supplier = buildSupplierWalletKey();
    const openUtxo = buildOpenEscrowUtxo();
    const oldDatum = decodeEscrowDatum(openUtxo.datumHex!);
    const result = await buildClaimTx({ chain, supplierKey: supplier, escrowRef: openUtxo.ref });
    const txHash = result.expectedTxHash;
    const newUtxo = await chain.queryUtxo({ txHash, index: 0 });
    const newDatum = decodeEscrowDatum(newUtxo!.datumHex!);
    // All fields except state must be identical
    expect(newDatum.buyer_pkh).toBe(oldDatum.buyer_pkh);
    expect(newDatum.supplier_pkh).toBe(oldDatum.supplier_pkh);
    expect(newDatum.advert_ref.txHash).toBe(oldDatum.advert_ref.txHash);
    expect(newDatum.prompt_hash).toBe(oldDatum.prompt_hash);
    expect(newDatum.payment_lovelace).toBe(oldDatum.payment_lovelace);
    expect(newDatum.deliver_by).toBe(oldDatum.deliver_by);
    expect(newDatum.submitted_at).toBeNull();
    expect(newDatum.result_receipt_hash).toBeNull();
  });

  it("validity upper-bound is ≤ deliver_by", async () => {
    const supplier = buildSupplierWalletKey();
    const utxo = buildOpenEscrowUtxo();
    const result = await buildClaimTx({ chain, supplierKey: supplier, escrowRef: utxo.ref });
    // The tx CBOR must encode a validity interval with upper bound ≤ deliver_by
    // We verify indirectly via the produced tx non-emptiness + no throw
    expect(result.txCborHex.length).toBeGreaterThan(0);
  });

  it("escrow UTxO is the only spending input", async () => {
    const supplier = buildSupplierWalletKey();
    const utxo = buildOpenEscrowUtxo();
    await buildClaimTx({ chain, supplierKey: supplier, escrowRef: utxo.ref });
    // Original UTxO should be spent (removed)
    const spent = await chain.queryUtxo(utxo.ref);
    expect(spent).toBeNull();
  });
});

// ─── Rejection: signed by non-supplier ───────────────────────────────────────

describe("buildClaimTx() — rejects non-supplier signer", () => {
  it("throws TxConstructionError when signed by buyer (not supplier)", async () => {
    const buyer = buildBuyerWalletKey();
    const chain = new MockChainProvider();
    chain.advanceSlot(Math.floor((DELIVER_BY - 100_000) / 1000));
    const utxo = buildOpenEscrowUtxo();
    chain.seed(utxo);

    await expect(
      buildClaimTx({ chain, supplierKey: buyer, escrowRef: utxo.ref }),
    ).rejects.toThrow(TxConstructionError);
  });

  it("TxConstructionError.reason is 'supplier signature mismatch'", async () => {
    const buyer = buildBuyerWalletKey();
    const chain = new MockChainProvider();
    chain.advanceSlot(Math.floor((DELIVER_BY - 100_000) / 1000));
    const utxo = buildOpenEscrowUtxo();
    chain.seed(utxo);

    let caught: unknown;
    try {
      await buildClaimTx({ chain, supplierKey: buyer, escrowRef: utxo.ref });
    } catch (e) {
      caught = e;
    }
    expect(caught).toBeInstanceOf(TxConstructionError);
    expect((caught as TxConstructionError).reason).toBe("supplier signature mismatch");
  });
});

// ─── Rejection: claim after deliver_by ───────────────────────────────────────

describe("buildClaimTx() — rejects claim after deliver_by", () => {
  it("throws TxConstructionError when chain tip is past deliver_by", async () => {
    const supplier = buildSupplierWalletKey();
    const chain = new MockChainProvider();
    // Tip is past deliver_by
    chain.advanceSlot(Math.floor((DELIVER_BY + 100_000) / 1000));
    const utxo = buildOpenEscrowUtxo();
    chain.seed(utxo);

    await expect(
      buildClaimTx({ chain, supplierKey: supplier, escrowRef: utxo.ref }),
    ).rejects.toThrow(TxConstructionError);
  });

  it("TxConstructionError.reason is 'claim after deliver_by'", async () => {
    const supplier = buildSupplierWalletKey();
    const chain = new MockChainProvider();
    chain.advanceSlot(Math.floor((DELIVER_BY + 100_000) / 1000));
    const utxo = buildOpenEscrowUtxo();
    chain.seed(utxo);

    let caught: unknown;
    try {
      await buildClaimTx({ chain, supplierKey: supplier, escrowRef: utxo.ref });
    } catch (e) {
      caught = e;
    }
    expect(caught).toBeInstanceOf(TxConstructionError);
    expect((caught as TxConstructionError).reason).toBe("claim after deliver_by");
  });
});

// ─── Rejection: wrong state ───────────────────────────────────────────────────

describe("buildClaimTx() — rejects wrong state", () => {
  it("throws TxConstructionError when escrow is already Claimed", async () => {
    const supplier = buildSupplierWalletKey();
    const chain = new MockChainProvider();
    chain.advanceSlot(Math.floor((DELIVER_BY - 100_000) / 1000));
    const utxo = buildClaimedEscrowUtxo();   // already Claimed
    chain.seed(utxo);

    await expect(
      buildClaimTx({ chain, supplierKey: supplier, escrowRef: utxo.ref }),
    ).rejects.toThrow(TxConstructionError);
  });
});