// NOTE: These tests use a testableService that reimplements service logic
// with mock repositories. This means tests can pass even if the real service
// diverges. For full coverage, consider refactoring services to use repository
// interfaces so the real service can be tested with mock repositories injected.

package bossraid

import (
	"encoding/json"
	"fmt"
	"testing"
	"time"

	"github.com/tolelom/tolchain/core"
)

// ---------------------------------------------------------------------------
// Mock repository — mirrors the methods that Service calls.
// Since Service uses concrete *Repository and Transaction(func(*Repository)),
// we create a testableService with an interface to enable mocking.
// ---------------------------------------------------------------------------

type repositoryInterface interface {
	Create(room *BossRoom) error
	Update(room *BossRoom) error
	FindBySessionName(sessionName string) (*BossRoom, error)
	FindBySessionNameForUpdate(sessionName string) (*BossRoom, error)
	CountActiveByUsername(username string) (int64, error)
	Transaction(fn func(txRepo repositoryInterface) error) error
}

type testableService struct {
	repo        repositoryInterface
	rewardGrant func(username string, tokenAmount uint64, assets []core.MintAssetPayload) error
}

func (s *testableService) RequestEntry(usernames []string, bossID int) (*BossRoom, error) {
	if len(usernames) == 0 {
		return nil, fmt.Errorf("플레이어 목록이 비어있습니다")
	}
	if len(usernames) > 3 {
		return nil, fmt.Errorf("최대 3명까지 입장할 수 있습니다")
	}

	seen := make(map[string]bool, len(usernames))
	for _, u := range usernames {
		if seen[u] {
			return nil, fmt.Errorf("중복된 플레이어가 있습니다: %s", u)
		}
		seen[u] = true
	}

	for _, username := range usernames {
		count, err := s.repo.CountActiveByUsername(username)
		if err != nil {
			return nil, fmt.Errorf("플레이어 상태 확인 실패: %w", err)
		}
		if count > 0 {
			return nil, fmt.Errorf("플레이어 %s가 이미 보스 레이드 중입니다", username)
		}
	}

	playersJSON, err := json.Marshal(usernames)
	if err != nil {
		return nil, fmt.Errorf("플레이어 목록 직렬화 실패: %w", err)
	}

	sessionName := fmt.Sprintf("BossRaid_%d_%d", bossID, time.Now().UnixNano())
	room := &BossRoom{
		SessionName: sessionName,
		BossID:      bossID,
		Status:      StatusWaiting,
		MaxPlayers:  3,
		Players:     string(playersJSON),
	}

	if err := s.repo.Create(room); err != nil {
		return nil, fmt.Errorf("방 생성 실패: %w", err)
	}

	return room, nil
}

func (s *testableService) CompleteRaid(sessionName string, rewards []PlayerReward) (*BossRoom, []RewardResult, error) {
	var resultRoom *BossRoom
	var resultRewards []RewardResult

	err := s.repo.Transaction(func(txRepo repositoryInterface) error {
		room, err := txRepo.FindBySessionNameForUpdate(sessionName)
		if err != nil {
			return fmt.Errorf("방을 찾을 수 없습니다: %w", err)
		}
		if room.Status != StatusInProgress {
			return fmt.Errorf("완료할 수 없는 상태입니다: %s", room.Status)
		}

		var players []string
		if err := json.Unmarshal([]byte(room.Players), &players); err != nil {
			return fmt.Errorf("플레이어 목록 파싱 실패: %w", err)
		}
		playerSet := make(map[string]bool, len(players))
		for _, p := range players {
			playerSet[p] = true
		}
		for _, r := range rewards {
			if !playerSet[r.Username] {
				return fmt.Errorf("보상 대상 %s가 방의 플레이어가 아닙니다", r.Username)
			}
		}

		now := time.Now()
		room.Status = StatusCompleted
		room.CompletedAt = &now
		if err := txRepo.Update(room); err != nil {
			return fmt.Errorf("상태 업데이트 실패: %w", err)
		}

		resultRoom = room
		return nil
	})
	if err != nil {
		return nil, nil, err
	}

	resultRewards = make([]RewardResult, 0, len(rewards))
	if s.rewardGrant != nil {
		for _, r := range rewards {
			grantErr := s.rewardGrant(r.Username, r.TokenAmount, r.Assets)
			result := RewardResult{Username: r.Username, Success: grantErr == nil}
			if grantErr != nil {
				result.Error = grantErr.Error()
			}
			resultRewards = append(resultRewards, result)
		}
	}

	return resultRoom, resultRewards, nil
}

func (s *testableService) FailRaid(sessionName string) (*BossRoom, error) {
	var resultRoom *BossRoom
	err := s.repo.Transaction(func(txRepo repositoryInterface) error {
		room, err := txRepo.FindBySessionNameForUpdate(sessionName)
		if err != nil {
			return fmt.Errorf("방을 찾을 수 없습니다: %w", err)
		}
		if room.Status != StatusWaiting && room.Status != StatusInProgress {
			return fmt.Errorf("실패 처리할 수 없는 상태입니다: %s", room.Status)
		}

		now := time.Now()
		room.Status = StatusFailed
		room.CompletedAt = &now
		if err := txRepo.Update(room); err != nil {
			return fmt.Errorf("상태 업데이트 실패: %w", err)
		}
		resultRoom = room
		return nil
	})
	if err != nil {
		return nil, err
	}
	return resultRoom, nil
}

// ---------------------------------------------------------------------------
// Mock implementation
// ---------------------------------------------------------------------------

type mockRepo struct {
	rooms           map[string]*BossRoom
	activeCounts    map[string]int64 // username -> active count
	nextID          uint
	createErr       error
	updateErr       error
	countActiveErr  error
}

func newMockRepo() *mockRepo {
	return &mockRepo{
		rooms:        make(map[string]*BossRoom),
		activeCounts: make(map[string]int64),
		nextID:       1,
	}
}

func (m *mockRepo) Create(room *BossRoom) error {
	if m.createErr != nil {
		return m.createErr
	}
	room.ID = m.nextID
	room.CreatedAt = time.Now()
	room.UpdatedAt = time.Now()
	m.nextID++
	stored := *room
	m.rooms[room.SessionName] = &stored
	return nil
}

func (m *mockRepo) Update(room *BossRoom) error {
	if m.updateErr != nil {
		return m.updateErr
	}
	room.UpdatedAt = time.Now()
	stored := *room
	m.rooms[room.SessionName] = &stored
	return nil
}

func (m *mockRepo) FindBySessionName(sessionName string) (*BossRoom, error) {
	room, ok := m.rooms[sessionName]
	if !ok {
		return nil, fmt.Errorf("record not found")
	}
	cp := *room
	return &cp, nil
}

func (m *mockRepo) FindBySessionNameForUpdate(sessionName string) (*BossRoom, error) {
	return m.FindBySessionName(sessionName)
}

func (m *mockRepo) CountActiveByUsername(username string) (int64, error) {
	if m.countActiveErr != nil {
		return 0, m.countActiveErr
	}
	return m.activeCounts[username], nil
}

func (m *mockRepo) Transaction(fn func(txRepo repositoryInterface) error) error {
	return fn(m)
}

// ---------------------------------------------------------------------------
// Tests: RequestEntry
// ---------------------------------------------------------------------------

func TestRequestEntry_Success(t *testing.T) {
	repo := newMockRepo()
	svc := &testableService{repo: repo}

	room, err := svc.RequestEntry([]string{"player1", "player2"}, 1)
	if err != nil {
		t.Fatalf("RequestEntry failed: %v", err)
	}
	if room.Status != StatusWaiting {
		t.Errorf("Status = %q, want %q", room.Status, StatusWaiting)
	}
	if room.BossID != 1 {
		t.Errorf("BossID = %d, want 1", room.BossID)
	}
	if room.MaxPlayers != 3 {
		t.Errorf("MaxPlayers = %d, want 3", room.MaxPlayers)
	}
}

func TestRequestEntry_EmptyPlayers(t *testing.T) {
	repo := newMockRepo()
	svc := &testableService{repo: repo}

	_, err := svc.RequestEntry([]string{}, 1)
	if err == nil {
		t.Error("expected error for empty player list, got nil")
	}
}

func TestRequestEntry_TooManyPlayers(t *testing.T) {
	repo := newMockRepo()
	svc := &testableService{repo: repo}

	_, err := svc.RequestEntry([]string{"p1", "p2", "p3", "p4"}, 1)
	if err == nil {
		t.Error("expected error for >3 players, got nil")
	}
}

func TestRequestEntry_DuplicatePlayers(t *testing.T) {
	repo := newMockRepo()
	svc := &testableService{repo: repo}

	_, err := svc.RequestEntry([]string{"player1", "player1"}, 1)
	if err == nil {
		t.Error("expected error for duplicate players, got nil")
	}
}

func TestRequestEntry_PlayerAlreadyInActiveRaid(t *testing.T) {
	repo := newMockRepo()
	repo.activeCounts["player1"] = 1
	svc := &testableService{repo: repo}

	_, err := svc.RequestEntry([]string{"player1", "player2"}, 1)
	if err == nil {
		t.Error("expected error when player is already in active raid, got nil")
	}
}

func TestRequestEntry_ThreePlayers(t *testing.T) {
	repo := newMockRepo()
	svc := &testableService{repo: repo}

	room, err := svc.RequestEntry([]string{"p1", "p2", "p3"}, 5)
	if err != nil {
		t.Fatalf("RequestEntry failed: %v", err)
	}

	var players []string
	if err := json.Unmarshal([]byte(room.Players), &players); err != nil {
		t.Fatalf("failed to parse Players JSON: %v", err)
	}
	if len(players) != 3 {
		t.Errorf("expected 3 players in JSON, got %d", len(players))
	}
}

// ---------------------------------------------------------------------------
// Tests: CompleteRaid
// ---------------------------------------------------------------------------

func TestCompleteRaid_Success(t *testing.T) {
	repo := newMockRepo()
	svc := &testableService{repo: repo}

	// Create a room and set it to in_progress
	room, _ := svc.RequestEntry([]string{"player1", "player2"}, 1)
	stored := repo.rooms[room.SessionName]
	stored.Status = StatusInProgress
	now := time.Now()
	stored.StartedAt = &now

	rewards := []PlayerReward{
		{Username: "player1", TokenAmount: 100},
		{Username: "player2", TokenAmount: 50},
	}

	completed, results, err := svc.CompleteRaid(room.SessionName, rewards)
	if err != nil {
		t.Fatalf("CompleteRaid failed: %v", err)
	}
	if completed.Status != StatusCompleted {
		t.Errorf("Status = %q, want %q", completed.Status, StatusCompleted)
	}
	if completed.CompletedAt == nil {
		t.Error("CompletedAt should be set")
	}
	// No reward granter set, so results should be empty
	if len(results) != 0 {
		t.Errorf("expected 0 reward results (no granter set), got %d", len(results))
	}
}

func TestCompleteRaid_WithRewardGranter(t *testing.T) {
	repo := newMockRepo()
	grantCalls := 0
	svc := &testableService{
		repo: repo,
		rewardGrant: func(username string, tokenAmount uint64, assets []core.MintAssetPayload) error {
			grantCalls++
			return nil
		},
	}

	room, _ := svc.RequestEntry([]string{"player1"}, 1)
	stored := repo.rooms[room.SessionName]
	stored.Status = StatusInProgress

	rewards := []PlayerReward{
		{Username: "player1", TokenAmount: 100},
	}

	_, results, err := svc.CompleteRaid(room.SessionName, rewards)
	if err != nil {
		t.Fatalf("CompleteRaid failed: %v", err)
	}
	if grantCalls != 1 {
		t.Errorf("expected 1 grant call, got %d", grantCalls)
	}
	if len(results) != 1 {
		t.Fatalf("expected 1 result, got %d", len(results))
	}
	if !results[0].Success {
		t.Errorf("expected success=true, got false")
	}
}

func TestCompleteRaid_RewardGranterFails(t *testing.T) {
	repo := newMockRepo()
	svc := &testableService{
		repo: repo,
		rewardGrant: func(username string, tokenAmount uint64, assets []core.MintAssetPayload) error {
			return fmt.Errorf("blockchain error")
		},
	}

	room, _ := svc.RequestEntry([]string{"player1"}, 1)
	stored := repo.rooms[room.SessionName]
	stored.Status = StatusInProgress

	rewards := []PlayerReward{
		{Username: "player1", TokenAmount: 100},
	}

	completed, results, err := svc.CompleteRaid(room.SessionName, rewards)
	if err != nil {
		t.Fatalf("CompleteRaid should not fail when reward granter fails: %v", err)
	}
	// Room should still be completed
	if completed.Status != StatusCompleted {
		t.Errorf("Status = %q, want %q", completed.Status, StatusCompleted)
	}
	if len(results) != 1 {
		t.Fatalf("expected 1 result, got %d", len(results))
	}
	if results[0].Success {
		t.Error("expected success=false for failed grant")
	}
	if results[0].Error == "" {
		t.Error("expected non-empty error message")
	}
}

func TestCompleteRaid_WrongStatus(t *testing.T) {
	repo := newMockRepo()
	svc := &testableService{repo: repo}

	room, _ := svc.RequestEntry([]string{"player1"}, 1)
	// Room is in "waiting" status, not "in_progress"

	_, _, err := svc.CompleteRaid(room.SessionName, nil)
	if err == nil {
		t.Error("expected error completing raid that is not in_progress, got nil")
	}
}

func TestCompleteRaid_InvalidRewardRecipient(t *testing.T) {
	repo := newMockRepo()
	svc := &testableService{repo: repo}

	room, _ := svc.RequestEntry([]string{"player1"}, 1)
	stored := repo.rooms[room.SessionName]
	stored.Status = StatusInProgress

	rewards := []PlayerReward{
		{Username: "not_a_member", TokenAmount: 100},
	}

	_, _, err := svc.CompleteRaid(room.SessionName, rewards)
	if err == nil {
		t.Error("expected error for reward to non-member, got nil")
	}
}

func TestCompleteRaid_RoomNotFound(t *testing.T) {
	repo := newMockRepo()
	svc := &testableService{repo: repo}

	_, _, err := svc.CompleteRaid("nonexistent_session", nil)
	if err == nil {
		t.Error("expected error for non-existent room, got nil")
	}
}

// ---------------------------------------------------------------------------
// Tests: FailRaid
// ---------------------------------------------------------------------------

func TestFailRaid_FromWaiting(t *testing.T) {
	repo := newMockRepo()
	svc := &testableService{repo: repo}

	room, _ := svc.RequestEntry([]string{"player1"}, 1)

	failed, err := svc.FailRaid(room.SessionName)
	if err != nil {
		t.Fatalf("FailRaid failed: %v", err)
	}
	if failed.Status != StatusFailed {
		t.Errorf("Status = %q, want %q", failed.Status, StatusFailed)
	}
	if failed.CompletedAt == nil {
		t.Error("CompletedAt should be set on failure")
	}
}

func TestFailRaid_FromInProgress(t *testing.T) {
	repo := newMockRepo()
	svc := &testableService{repo: repo}

	room, _ := svc.RequestEntry([]string{"player1"}, 1)
	stored := repo.rooms[room.SessionName]
	stored.Status = StatusInProgress

	failed, err := svc.FailRaid(room.SessionName)
	if err != nil {
		t.Fatalf("FailRaid failed: %v", err)
	}
	if failed.Status != StatusFailed {
		t.Errorf("Status = %q, want %q", failed.Status, StatusFailed)
	}
}

func TestFailRaid_FromCompleted(t *testing.T) {
	repo := newMockRepo()
	svc := &testableService{repo: repo}

	room, _ := svc.RequestEntry([]string{"player1"}, 1)
	stored := repo.rooms[room.SessionName]
	stored.Status = StatusCompleted

	_, err := svc.FailRaid(room.SessionName)
	if err == nil {
		t.Error("expected error failing already-completed raid, got nil")
	}
}

func TestFailRaid_FromFailed(t *testing.T) {
	repo := newMockRepo()
	svc := &testableService{repo: repo}

	room, _ := svc.RequestEntry([]string{"player1"}, 1)
	stored := repo.rooms[room.SessionName]
	stored.Status = StatusFailed

	_, err := svc.FailRaid(room.SessionName)
	if err == nil {
		t.Error("expected error failing already-failed raid, got nil")
	}
}

func TestFailRaid_RoomNotFound(t *testing.T) {
	repo := newMockRepo()
	svc := &testableService{repo: repo}

	_, err := svc.FailRaid("nonexistent_session")
	if err == nil {
		t.Error("expected error for non-existent room, got nil")
	}
}

// ---------------------------------------------------------------------------
// Tests: State machine transitions
// ---------------------------------------------------------------------------

func TestStateMachine_FullLifecycle(t *testing.T) {
	repo := newMockRepo()
	svc := &testableService{repo: repo}

	// 1. Create room (waiting)
	room, err := svc.RequestEntry([]string{"p1", "p2"}, 1)
	if err != nil {
		t.Fatalf("RequestEntry failed: %v", err)
	}
	if room.Status != StatusWaiting {
		t.Fatalf("expected waiting, got %s", room.Status)
	}

	// 2. Simulate start (set to in_progress)
	stored := repo.rooms[room.SessionName]
	stored.Status = StatusInProgress
	now := time.Now()
	stored.StartedAt = &now

	// 3. Complete
	completed, _, err := svc.CompleteRaid(room.SessionName, []PlayerReward{
		{Username: "p1", TokenAmount: 10},
	})
	if err != nil {
		t.Fatalf("CompleteRaid failed: %v", err)
	}
	if completed.Status != StatusCompleted {
		t.Errorf("expected completed, got %s", completed.Status)
	}

	// 4. Cannot fail a completed raid
	_, err = svc.FailRaid(room.SessionName)
	if err == nil {
		t.Error("expected error failing completed raid")
	}
}

func TestStateMachine_WaitingToFailed(t *testing.T) {
	repo := newMockRepo()
	svc := &testableService{repo: repo}

	room, _ := svc.RequestEntry([]string{"p1"}, 1)

	failed, err := svc.FailRaid(room.SessionName)
	if err != nil {
		t.Fatalf("FailRaid failed: %v", err)
	}
	if failed.Status != StatusFailed {
		t.Errorf("expected failed, got %s", failed.Status)
	}

	// Cannot complete a failed raid
	stored := repo.rooms[room.SessionName]
	stored.Status = StatusFailed
	_, _, err = svc.CompleteRaid(room.SessionName, nil)
	if err == nil {
		t.Error("expected error completing failed raid")
	}
}