package banksync

import (
	"context"
	"fuj-management/go/internal/domain/synch"
	"fuj-management/go/internal/io/fio"
	"fuj-management/go/internal/io/sheets"
	"testing"
	"time"
)

var testFioTxns = []fio.Transaction{
	{Date: "2026-04-10", Amount: 750, Sender: "Jana Novakova", Message: "duben 2026", VS: "123", BankID: "111"},
	{Date: "2026-04-11", Amount: 500, Sender: "Petr Prach", Message: "april", VS: "456", BankID: "222"},
}

func TestSyncToSheets_EmptySheet(t *testing.T) {
	sh := &sheets.Fake{Values: map[string][][]any{
		"SHEETID/A1:K": {},
	}}
	fioFake := &fio.Fake{Transactions: testFioTxns}

	n, err := SyncToSheets(context.Background(), "SHEETID", fioFake, sh, SyncOpts{Days: 30})
	if err != nil {
		t.Fatal(err)
	}
	if n != 2 {
		t.Errorf("want 2 appended, got %d", n)
	}
	if len(sh.Appended) != 1 {
		t.Fatalf("want 1 AppendValues call, got %d", len(sh.Appended))
	}
	rows := sh.Appended[0].Rows
	if len(rows) != 2 {
		t.Errorf("want 2 rows in append call, got %d", len(rows))
	}
	// Sync ID should be in column 10 (index 10)
	if syncID, ok := rows[0][10].(string); !ok || len(syncID) != 64 {
		t.Errorf("expected 64-char hex sync ID, got %v", rows[0][10])
	}
}

func TestSyncToSheets_Dedup(t *testing.T) {
	// Seed the sheet with an existing sync ID matching testFioTxns[0]
	firstID := syncIDFor(testFioTxns[0])
	sh := &sheets.Fake{Values: map[string][][]any{
		"SHEETID/A1:K": {
			{"Date", "Amount", "manual fix", "Person", "Purpose", "Inferred Amount", "Sender", "VS", "Message", "Bank ID", "Sync ID"},
			{"2026-04-10", 750.0, "", "", "", "", "Jana Novakova", "123", "duben 2026", "111", firstID},
		},
	}}
	fioFake := &fio.Fake{Transactions: testFioTxns}

	n, err := SyncToSheets(context.Background(), "SHEETID", fioFake, sh, SyncOpts{Days: 30})
	if err != nil {
		t.Fatal(err)
	}
	if n != 1 {
		t.Errorf("want 1 new row (one deduped), got %d", n)
	}
}

func TestSyncToSheets_NoNewTxns(t *testing.T) {
	first := syncIDFor(testFioTxns[0])
	second := syncIDFor(testFioTxns[1])
	sh := &sheets.Fake{Values: map[string][][]any{
		"SHEETID/A1:K": {
			{"Date", "Amount", "manual fix", "Person", "Purpose", "Inferred Amount", "Sender", "VS", "Message", "Bank ID", "Sync ID"},
			{"2026-04-10", 750.0, "", "", "", "", "Jana Novakova", "123", "duben 2026", "111", first},
			{"2026-04-11", 500.0, "", "", "", "", "Petr Prach", "456", "april", "222", second},
		},
	}}
	fioFake := &fio.Fake{Transactions: testFioTxns}

	n, err := SyncToSheets(context.Background(), "SHEETID", fioFake, sh, SyncOpts{Days: 30})
	if err != nil {
		t.Fatal(err)
	}
	if n != 0 {
		t.Errorf("want 0 new rows, got %d", n)
	}
	if len(sh.Appended) != 0 {
		t.Error("expected no AppendValues call when all deduped")
	}
}

func TestSyncToSheets_MissingHeader(t *testing.T) {
	sh := &sheets.Fake{Values: map[string][][]any{
		"SHEETID/A1:K": {
			{"Wrong", "Headers"},
		},
	}}
	fioFake := &fio.Fake{Transactions: testFioTxns[:1]}

	n, err := SyncToSheets(context.Background(), "SHEETID", fioFake, sh, SyncOpts{Days: 30})
	if err != nil {
		t.Fatal(err)
	}
	if n != 1 {
		t.Errorf("want 1 row appended after header fix, got %d", n)
	}
}

func TestSyncToSheets_Sort(t *testing.T) {
	sh := &sheets.Fake{Values: map[string][][]any{"SHEETID/A1:K": {}}}
	fioFake := &fio.Fake{Transactions: testFioTxns[:1]}

	_, err := SyncToSheets(context.Background(), "SHEETID", fioFake, sh, SyncOpts{Days: 30, Sort: true})
	if err != nil {
		t.Fatal(err)
	}
	// SortByDateColumn should have been called on the fake — check via a spy fake
}

func TestSyncToSheets_ExplicitDateWindow(t *testing.T) {
	sh := &sheets.Fake{Values: map[string][][]any{"SHEETID/A1:K": {}}}
	fioFake := &fio.Fake{Transactions: testFioTxns[:1]}

	from := time.Date(2026, 4, 1, 0, 0, 0, 0, time.UTC)
	to := time.Date(2026, 4, 30, 0, 0, 0, 0, time.UTC)
	n, err := SyncToSheets(context.Background(), "SHEETID", fioFake, sh, SyncOpts{From: from, To: to})
	if err != nil {
		t.Fatal(err)
	}
	if n != 1 {
		t.Errorf("want 1 row, got %d", n)
	}
}

func TestSyncToSheets_DryRun(t *testing.T) {
	sh := &sheets.Fake{Values: map[string][][]any{"SHEETID/A1:K": {}}}
	fioFake := &fio.Fake{Transactions: testFioTxns}

	n, err := SyncToSheets(context.Background(), "SHEETID", fioFake, sh,
		SyncOpts{Days: 30, Sort: true, DryRun: true})
	if err != nil {
		t.Fatal(err)
	}
	if n != 2 {
		t.Errorf("want 2 planned, got %d", n)
	}
	if len(sh.Appended) != 0 {
		t.Error("dry-run must not call AppendValues")
	}
}

// syncIDFor mirrors what SyncToSheets computes for a given fio.Transaction.
func syncIDFor(tx fio.Transaction) string {
	currency := tx.Currency
	if currency == "" {
		currency = "CZK"
	}
	return synch.GenerateSyncID(synch.Transaction{
		Date: tx.Date, Amount: tx.Amount, Currency: currency,
		Sender: tx.Sender, VS: tx.VS, Message: tx.Message, BankID: tx.BankID,
	})
}