package membership

import (
	"context"
	"fuj-management/go/internal/config"
	"fuj-management/go/internal/io/attendance"
	"fuj-management/go/internal/io/cache"
	"fuj-management/go/internal/io/drive"
	"fuj-management/go/internal/io/sheets"
	"testing"
	"time"
)

// buildSources wires a realSources with in-memory fakes and a no-TTL cache.
func buildSources(t *testing.T, att *attendance.Fake, sh *sheets.Fake) *realSources {
	t.Helper()
	dir := t.TempDir()
	d := &drive.Fake{Times: map[string]string{
		config.AttendanceSheetID: "t1",
		config.PaymentsSheetID:   "t1",
	}}
	fc := cache.New(d, dir, config.CacheSheetMap, 0, 0)
	return &realSources{attendance: att, sheets: sh, cache: fc}
}

var minimalAdultCSV = [][]string{
	{"Jméno", "Tier", "", "", "01.09.2025", "08.09.2025"},
	{"Alice", "A", "", "", "TRUE", "TRUE"},
	{"Bob", "A", "", "", "TRUE", "FALSE"},
	{"# last line"},
}

// minimalJuniorCSV has dates in October because the junior merged-month map sends
// 2025-09 → 2025-10, so two columns for 01.10.2025 and 08.10.2025 land in "2025-10".
var minimalJuniorCSV = [][]string{
	{"Jméno", "Tier", "", "", "01.10.2025", "08.10.2025"},
	{"Charlie", "J", "", "", "TRUE", "TRUE"},
	{"# Trenéři"},
	{"Coach", "X", "", "", "FALSE", "FALSE"},
}

func TestLoadAdults(t *testing.T) {
	s := buildSources(t, &attendance.Fake{Adults: minimalAdultCSV}, &sheets.Fake{})

	members, months, err := s.LoadAdults(context.Background())
	if err != nil {
		t.Fatal(err)
	}
	// adultMergedMonths is empty so 2025-09 stays as-is
	if len(months) != 1 || months[0] != "2025-09" {
		t.Errorf("unexpected months: %v", months)
	}
	if len(members) != 2 {
		t.Fatalf("want 2 members, got %d", len(members))
	}
	byName := map[string]int{}
	for _, m := range members {
		byName[m.Name] = m.Fees["2025-09"].Attendance
	}
	if byName["Alice"] != 2 {
		t.Errorf("Alice: want 2 sessions, got %d", byName["Alice"])
	}
	if byName["Bob"] != 1 {
		t.Errorf("Bob: want 1 session, got %d", byName["Bob"])
	}
}

func TestLoadAdults_Fee(t *testing.T) {
	s := buildSources(t, &attendance.Fake{Adults: minimalAdultCSV}, &sheets.Fake{})
	members, _, err := s.LoadAdults(context.Background())
	if err != nil {
		t.Fatal(err)
	}
	byName := map[string]int{}
	for _, m := range members {
		byName[m.Name] = m.Fees["2025-09"].Expected
	}
	// 2 sessions in 2025-09 → AdultFeeMonthlyRate["2025-09"] = 750
	if byName["Alice"] != 750 {
		t.Errorf("Alice fee: want 750, got %d", byName["Alice"])
	}
	// 1 session → AdultFeeSingle = 200
	if byName["Bob"] != 200 {
		t.Errorf("Bob fee: want 200, got %d", byName["Bob"])
	}
}

func TestLoadJuniors(t *testing.T) {
	s := buildSources(t,
		&attendance.Fake{Adults: minimalAdultCSV, Juniors: minimalJuniorCSV},
		&sheets.Fake{})

	members, months, err := s.LoadJuniors(context.Background())
	if err != nil {
		t.Fatal(err)
	}
	if len(months) == 0 {
		t.Fatal("want months, got none")
	}
	found := false
	for _, m := range members {
		if m.Name == "Charlie" {
			found = true
			// Charlie has 2 sessions in 2025-10 (October dates in junior CSV)
			if m.Fees["2025-10"].Attendance != 2 {
				t.Errorf("Charlie 2025-10 attendance: want 2, got %d", m.Fees["2025-10"].Attendance)
			}
		}
	}
	if !found {
		t.Error("Charlie not found in juniors")
	}
}

func TestLoadTransactions(t *testing.T) {
	// Sheets fake keyed by "<spreadsheetID>/<range>" — use the real constant.
	paymentsKey := config.PaymentsSheetID + "/A1:Z"
	sh := &sheets.Fake{Values: map[string][][]any{
		paymentsKey: {
			{"Date", "Amount", "manual fix", "Person", "Purpose", "Inferred Amount", "Sender", "VS", "Message", "Bank ID", "Sync ID"},
			{"2026-04-01", 700.0, "", "Alice", "2026-04", "", "Alice Bank", "", "fee", "", "abc"},
			{"2026-05-01", 500.0, "", "", "", "", "Bob Bank", "", "platba", "", "def"},
		},
	}}
	s := buildSources(t, &attendance.Fake{}, sh)

	txns, err := s.LoadTransactions(context.Background())
	if err != nil {
		t.Fatal(err)
	}
	if len(txns) != 2 {
		t.Fatalf("want 2 transactions, got %d", len(txns))
	}
	if txns[0].Person != "Alice" {
		t.Errorf("txn[0].Person: want Alice, got %q", txns[0].Person)
	}
	if txns[0].Amount != 700 {
		t.Errorf("txn[0].Amount: want 700, got %v", txns[0].Amount)
	}
}

func TestLoadExceptions(t *testing.T) {
	excKey := config.PaymentsSheetID + "/'exceptions'!A2:D"
	sh := &sheets.Fake{Values: map[string][][]any{
		excKey: {
			{"Alice", "2026-04", 350, "reduced"},
		},
	}}
	s := buildSources(t, &attendance.Fake{}, sh)

	exc, err := s.LoadExceptions(context.Background())
	if err != nil {
		t.Fatal(err)
	}
	if len(exc) != 1 {
		t.Fatalf("want 1 exception, got %d", len(exc))
	}
	for k, v := range exc {
		if v.Amount != 350 {
			t.Errorf("exception amount: want 350, got %d (key=%v)", v.Amount, k)
		}
		if v.Note != "reduced" {
			t.Errorf("exception note: want 'reduced', got %q", v.Note)
		}
	}
}

// TTL smoke test: second call within TTL must not call fetch again.
func TestLoadAdults_CacheHit(t *testing.T) {
	dir := t.TempDir()
	d := &drive.Fake{Times: map[string]string{config.AttendanceSheetID: "t1"}}
	fc := cache.New(d, dir, config.CacheSheetMap, time.Minute, time.Minute)

	calls := 0
	att := &countingFetcher{rows: minimalAdultCSV, calls: &calls}
	s := &realSources{attendance: att, sheets: &sheets.Fake{}, cache: fc}

	if _, _, err := s.LoadAdults(context.Background()); err != nil {
		t.Fatal(err)
	}
	if _, _, err := s.LoadAdults(context.Background()); err != nil {
		t.Fatal(err)
	}
	if calls != 1 {
		t.Errorf("want 1 fetch (cache hit on 2nd call), got %d", calls)
	}
}

type countingFetcher struct {
	rows  [][]string
	calls *int
}

func (f *countingFetcher) FetchAdults(_ context.Context) ([][]string, error) {
	*f.calls++
	return f.rows, nil
}
func (f *countingFetcher) FetchJuniors(_ context.Context) ([][]string, error) { return nil, nil }