package app

import (
	"context"
	"errors"
	"reflect"
	"testing"
	"time"

	"finance-duck/internal/banking"
	"finance-duck/internal/domain"
)

type bankScenario struct {
	session banking.Session
	fail    bool
}

func (b *bankScenario) Authorize(context.Context, string, string, string) (string, error) {
	return "https://bank.example/authorize", nil
}
func (b *bankScenario) Exchange(context.Context, string) (banking.Session, error) {
	return b.session, nil
}
func (b *bankScenario) Status(context.Context, string) (banking.Session, error) {
	if b.fail {
		return banking.Session{}, errors.New("expired")
	}
	return b.session, nil
}
func (b *bankScenario) Balances(context.Context, string) ([]banking.Balance, error) {
	return []banking.Balance{{Amount: "100.00", Currency: "EUR", Type: "CLBD"}}, nil
}
func (b *bankScenario) Transactions(_ context.Context, a domain.Account, from, to string) ([]domain.Facts, error) {
	if b.fail {
		return nil, errors.New("offline")
	}
	return []domain.Facts{{Source: "enablebanking", AccountID: a.ID, BookingDate: time.Now().UTC().AddDate(0, 0, -1).Format("2006-01-02"), Amount: "-42.80", Currency: "EUR", RawDescription: "REWE", ExternalID: "entry_stable"}}, nil
}
func TestSyncRestoresSavedConsentBindingsAndDoesNotDuplicateFacts(t *testing.T) {
	a, s := testApp(t)
	account := s.Data.Accounts[0]
	account.ExternalAccountID = "provider_new"
	account.IBAN = "DE89370400440532013000"
	provider := &bankScenario{session: banking.Session{ID: "new_session", ValidUntil: time.Now().Add(24 * time.Hour).Format(time.RFC3339), Accounts: []domain.Account{account}}}
	a.bank = provider
	a.ops.Sessions = []banking.Session{provider.session}
	if err := a.saveOps(); err != nil {
		t.Fatal(err)
	}
	first, err := a.Sync(context.Background())
	if err != nil {
		t.Fatal(err)
	}
	if len(first.Data.Accounts) != 1 || first.Data.Accounts[0].ExternalAccountID != "provider_new" || len(first.Data.Transactions) != 1 {
		t.Fatalf("saved session did not recover/import: %+v", first.Data)
	}
	again, err := a.Sync(context.Background())
	if err != nil {
		t.Fatal(err)
	}
	if !reflect.DeepEqual(first.Data, again.Data) {
		t.Fatal("repeated bank synchronization changed canonical financial data")
	}
	provider.fail = true
	failed, err := a.Sync(context.Background())
	if err != nil {
		t.Fatal(err)
	}
	if failed.Status.SyncError == "" || !reflect.DeepEqual(again.Data, failed.Data) {
		t.Fatal("provider failure was not isolated from canonical data")
	}
}
func TestReconnectReplacesOldConsentWithoutDuplicatingLocalAccount(t *testing.T) {
	a, s := testApp(t)
	account := s.Data.Accounts[0]
	account.ExternalAccountID = "old_uid"
	account.IBAN = "DE89370400440532013000"
	s, err := a.Mutate(context.Background(), s.Revision, func(d *domain.Dataset) error { return SaveAccount(d, account) })
	if err != nil {
		t.Fatal(err)
	}
	a.ops.Sessions = []banking.Session{{ID: "old_session", Accounts: []domain.Account{account}}}
	renewed := account
	renewed.ID = "provider_local_id"
	renewed.ExternalAccountID = "new_uid"
	renewed.DisplayName = "Bank-generated name"
	a.bank = &bankScenario{session: banking.Session{ID: "new_session", ValidUntil: time.Now().Add(24 * time.Hour).Format(time.RFC3339), Accounts: []domain.Account{renewed}}}
	a.authStates["one_time_state"] = authorization{Expires: time.Now().Add(time.Minute), Institution: "N26", Country: "DE"}
	if err = a.Callback(context.Background(), "bank_code", "one_time_state"); err != nil {
		t.Fatal(err)
	}
	after, err := a.Snapshot(context.Background())
	if err != nil {
		t.Fatal(err)
	}
	if len(after.Data.Accounts) != 1 || after.Data.Accounts[0].ID != account.ID || after.Data.Accounts[0].DisplayName != account.DisplayName || after.Data.Accounts[0].ExternalAccountID != "new_uid" {
		t.Fatal("reconnect duplicated account or lost local display name")
	}
	if len(after.Sessions) != 1 || after.Sessions[0].ID != "new_session" {
		t.Fatal("expired session remains active after reconnect")
	}
	if err = a.Callback(context.Background(), "bank_code", "one_time_state"); err == nil {
		t.Fatal("authorization state replay was accepted")
	}
}