package order

import (
	"context"
	"testing"

	"github.com/btcsuite/btcd/btcutil"
	"github.com/lightninglabs/pool/account"
	"github.com/lightninglabs/pool/auctioneerrpc"
	"github.com/lightninglabs/pool/internal/test"
	"github.com/lightninglabs/pool/sidecar"
	"github.com/lightninglabs/pool/terms"
	"github.com/lightningnetwork/lnd/keychain"
	"github.com/stretchr/testify/require"
)

// TestValidateOrderAccountIsolation tests that when we go to validate that an
// account has sufficient balance for an order, we only factor in the
// outstanding orders for that account, and not all total orders that are open.
func TestValidateOrderAccountIsolation(t *testing.T) {
	t.Parallel()

	orderStore := newMockStore()
	orderManager := NewManager(&ManagerConfig{
		Store:        orderStore,
		BatchVersion: LatestBatchVersion,
	})

	// We'll now create two accounts, one that's 1 BTC in size, while the
	// other is 2 BTC.
	accountA := account.Account{
		Value: btcutil.SatoshiPerBitcoin,
		TraderKey: &keychain.KeyDescriptor{
			PubKey: acctKeySmall,
		},
	}
	accountB := account.Account{
		Value: btcutil.SatoshiPerBitcoin * 2,
		TraderKey: &keychain.KeyDescriptor{
			PubKey: acctKeyBig,
		},
	}

	// We'll now create an order that will consume at least half (1100
	// units is 1.1 BTC) of account B (it's an ask order).
	var acctKeyB [33]byte
	copy(acctKeyB[:], acctKeyBig.SerializeCompressed())
	orderB := &Ask{
		Kit: newKitFromTemplate(Nonce{0x01}, &Kit{
			State:            StateSubmitted,
			UnitsUnfulfilled: 1100,
			FixedRate:        2_000,
			MaxBatchFeeRate:  1000,
			AcctKey:          acctKeyB,
			LeaseDuration:    144,
			MinUnitsMatch:    100,
		}),
	}

	testTerms := &terms.AuctioneerTerms{
		OrderExecBaseFee: 1,
		OrderExecFeeRate: 100,
		LeaseDurationBuckets: map[uint32]auctioneerrpc.DurationBucketState{
			144: auctioneerrpc.DurationBucketState_MARKET_OPEN,
		},
	}

	// Submitting this order for account B should pass validation.
	err := orderManager.validateOrder(orderB, &accountB, testTerms)
	if err != nil {
		t.Fatalf("order B validation failed: %v", err)
	}

	// Simulating order acceptance, we'll now add this order to the order
	// store.
	if err := orderStore.SubmitOrder(orderB); err != nil {
		t.Fatalf("unable to submit order: %v", err)
	}

	// Next, we'll create a ask that'll consume _most_ (but not all) of account
	// A's balance. This should pass validation as although account B can't
	// handle the order account A can.
	var acctKeyA [33]byte
	copy(acctKeyA[:], acctKeySmall.SerializeCompressed())
	orderA := &Ask{
		Kit: newKitFromTemplate(Nonce{0x01}, &Kit{
			State:            StateSubmitted,
			UnitsUnfulfilled: 800,
			FixedRate:        2_000,
			MaxBatchFeeRate:  1000,
			AcctKey:          acctKeyA,
			LeaseDuration:    144,
			MinUnitsMatch:    100,
		}),
	}

	err = orderManager.validateOrder(orderA, &accountA, testTerms)
	if err != nil {
		t.Fatalf("order A failed validation: %v", err)
	}
}

// TestValidateOrder makes sure that the order manager properly validates
// all conditions for submitting orders, especially the conditions for using the
// self channel balance.
func TestValidateOrder(t *testing.T) {
	t.Parallel()

	orderStore := newMockStore()
	orderManager := NewManager(&ManagerConfig{
		Store:        orderStore,
		BatchVersion: LatestBatchVersion,
	})

	// We'll now create an account with sufficient size.
	testAccount := &account.Account{
		Value: btcutil.SatoshiPerBitcoin,
		TraderKey: &keychain.KeyDescriptor{
			PubKey: acctKeySmall,
		},
	}

	testTerms := &terms.AuctioneerTerms{
		OrderExecBaseFee: 1,
		OrderExecFeeRate: 100,
		LeaseDurationBuckets: map[uint32]auctioneerrpc.DurationBucketState{
			144: auctioneerrpc.DurationBucketState_MARKET_OPEN,
		},
	}

	testCases := []struct {
		name        string
		expectedErr string
		order       Order
	}{{
		name:        "invalid lease duration",
		expectedErr: "invalid lease duration, must be one of map[144",
		order: &Ask{
			Kit: Kit{
				LeaseDuration: 123,
			},
		},
	}, {
		name:        "invalid max batch fee rate",
		expectedErr: "invalid max batch fee rate 123 sat/kw, must be",
		order: &Ask{
			Kit: Kit{
				LeaseDuration:   144,
				MaxBatchFeeRate: 123,
			},
		},
	}, {
		name:        "insufficient account balance",
		expectedErr: "insufficient account balance",
		order: &Ask{
			Kit: Kit{
				LeaseDuration:    144,
				MaxBatchFeeRate:  253,
				MinUnitsMatch:    1,
				Amt:              btcutil.SatoshiPerBitcoin,
				UnitsUnfulfilled: 1_000,
			},
		},
	}, {
		name: "invalid version for self chan balance",
		expectedErr: "cannot use self chan balance with old order " +
			"version",
		order: &Bid{
			Kit: Kit{
				LeaseDuration:    144,
				MaxBatchFeeRate:  253,
				MinUnitsMatch:    1,
				Amt:              100_000,
				UnitsUnfulfilled: 1,
			},
			SelfChanBalance: 1,
		},
	}, {
		name:        "invalid capacity for self chan balance",
		expectedErr: "channel capacity must be positive multiple of",
		order: &Bid{
			Kit: Kit{
				Version:          VersionSelfChanBalance,
				LeaseDuration:    144,
				MaxBatchFeeRate:  253,
				MinUnitsMatch:    1,
				Amt:              0,
				UnitsUnfulfilled: 0,
			},
			SelfChanBalance: 1,
		},
	}, {
		name: "invalid self chan balance",
		expectedErr: "self channel balance must be smaller than " +
			"or equal to capacity",
		order: &Bid{
			Kit: Kit{
				Version:          VersionSelfChanBalance,
				LeaseDuration:    144,
				MaxBatchFeeRate:  253,
				MinUnitsMatch:    1,
				Amt:              100_000,
				UnitsUnfulfilled: 1,
			},
			SelfChanBalance: 100_001,
		},
	}, {
		name: "min units match must equal amount",
		expectedErr: "to use self chan balance the min units match " +
			"must be equal to the order amount in units",
		order: &Bid{
			Kit: Kit{
				Version:          VersionSelfChanBalance,
				LeaseDuration:    144,
				MaxBatchFeeRate:  253,
				MinUnitsMatch:    1,
				Amt:              200_000,
				UnitsUnfulfilled: 2,
			},
			SelfChanBalance: 50_000,
		},
	}, {
		name:        "happy path",
		expectedErr: "",
		order: &Bid{
			Kit: Kit{
				Version:          VersionSelfChanBalance,
				LeaseDuration:    144,
				MaxBatchFeeRate:  253,
				MinUnitsMatch:    1,
				Amt:              100_000,
				UnitsUnfulfilled: 1,
				Units:            1,
			},
			SelfChanBalance: 10_000,
		},
	}}

	for _, tc := range testCases {
		tc := tc

		t.Run(tc.name, func(t *testing.T) {
			err := orderManager.validateOrder(
				tc.order, testAccount, testTerms,
			)

			if tc.expectedErr == "" {
				require.NoError(t, err)
			} else {
				require.Error(t, err)
				require.Contains(t, err.Error(), tc.expectedErr)
			}
		})
	}
}

type mockAccountStore struct {
	account.Store
}

// TestPrepareOrderSidecarTicket makes sure that a bid order with a sidecar
// ticket can be submitted and verified successfully.
func TestPrepareOrderSidecarTicket(t *testing.T) {
	t.Parallel()

	mockLightning := test.NewMockLightning()
	mockSigner := test.NewMockSigner()
	mgr := NewManager(&ManagerConfig{
		AcctStore:    &mockAccountStore{},
		Wallet:       test.NewMockWalletKit(),
		Lightning:    mockLightning,
		Signer:       mockSigner,
		BatchVersion: LatestBatchVersion,
	})
	require.NoError(t, mgr.Start())
	defer mgr.Stop()

	acct := &account.Account{
		Value: btcutil.SatoshiPerBitcoin,
		TraderKey: &keychain.KeyDescriptor{
			PubKey: acctKeySmall,
		},
	}
	var acctKey [33]byte
	copy(acctKey[:], acct.TraderKey.PubKey.SerializeCompressed())
	bid := &Bid{
		Kit: newKitFromTemplate(Nonce{0x01}, &Kit{
			Amt:             5_000_000,
			State:           StateSubmitted,
			AcctKey:         acctKey,
			MaxBatchFeeRate: 1000,
			LeaseDuration:   2016,
			MinUnitsMatch:   50,
		}),
	}

	testTerms := &terms.AuctioneerTerms{
		OrderExecBaseFee: 1,
		OrderExecFeeRate: 100,
		LeaseDurationBuckets: map[uint32]auctioneerrpc.DurationBucketState{
			2016: auctioneerrpc.DurationBucketState_MARKET_OPEN,
		},
	}

	testSig := test.NewSignatureFromInt(44, 22)

	mockSigner.Signature = testSig.Serialize()

	testCases := []struct {
		name        string
		ticket      *sidecar.Ticket
		expectedErr string
	}{{
		name:        "no ticket",
		expectedErr: "",
	}, {
		name:        "empty ticket",
		ticket:      &sidecar.Ticket{},
		expectedErr: "invalid sidecar ticket state",
	}, {
		name: "wrong data for state",
		ticket: &sidecar.Ticket{
			State: sidecar.StateRegistered,
		},
		expectedErr: "invalid sidecar ticket, missing recipient",
	}, {
		name: "wrong data for state",
		ticket: &sidecar.Ticket{
			State: sidecar.StateRegistered,
			Recipient: &sidecar.Recipient{
				NodePubKey:     acctKeySmall,
				MultiSigPubKey: acctKeySmall,
			},
		},
		expectedErr: "offer in ticket is not signed",
	}, {
		name: "good signature, incorrect offer amount",
		ticket: &sidecar.Ticket{
			State: sidecar.StateRegistered,
			Offer: sidecar.Offer{
				SigOfferDigest: testSig,
				SignPubKey:     acctKeySmall,
			},
			Recipient: &sidecar.Recipient{
				NodePubKey:     acctKeySmall,
				MultiSigPubKey: acctKeyBig,
			},
		},
		expectedErr: "channel capacity must be positive multiple of",
	}, {
		name: "all valid",
		ticket: &sidecar.Ticket{
			State: sidecar.StateRegistered,
			Offer: sidecar.Offer{
				SigOfferDigest: testSig,
				SignPubKey:     acctKeySmall,
				Capacity:       5_000_000,
			},
			Recipient: &sidecar.Recipient{
				NodePubKey:     acctKeySmall,
				MultiSigPubKey: acctKeyBig,
			},
		},
		expectedErr: "",
	}}

	for _, tc := range testCases {
		tc := tc

		bid.SidecarTicket = tc.ticket
		if tc.ticket != nil {
			digest, err := tc.ticket.OfferDigest()
			require.NoError(t, err)
			mockSigner.SignatureMsg = string(digest[:])
		}

		mgr.cfg.Store = newMockStore()
		_, err := mgr.PrepareOrder(
			context.Background(), bid, acct, testTerms,
		)

		if tc.expectedErr == "" {
			require.NoError(t, err)

			if tc.ticket != nil {
				require.NotNil(t, tc.ticket.Order)
				require.Equal(
					t, testSig,
					tc.ticket.Order.SigOrderDigest,
				)
				require.Equal(
					t, [32]byte(bid.nonce),
					tc.ticket.Order.BidNonce,
				)
			}
		} else {
			require.Error(t, err)
			require.Contains(t, err.Error(), tc.expectedErr)
		}
	}
}