package service

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

	membershipmodel "wx_service/internal/membership/model"
	usermodel "wx_service/internal/model"

	"gorm.io/driver/sqlite"
	"gorm.io/gorm"
	"gorm.io/gorm/logger"
)

func setupRedeemTestDB(t *testing.T) *gorm.DB {
	t.Helper()

	db, err := gorm.Open(sqlite.Open(":memory:"), &gorm.Config{
		Logger: logger.Default.LogMode(logger.Silent),
	})
	if err != nil {
		t.Fatalf("open sqlite: %v", err)
	}

	if err := db.AutoMigrate(
		&membershipmodel.MembershipRedeemCode{},
		&membershipmodel.MembershipRedemption{},
		&usermodel.UserMembership{},
	); err != nil {
		t.Fatalf("auto migrate: %v", err)
	}

	return db
}

func seedRedeemCode(t *testing.T, db *gorm.DB, plainCode string, durationDays int, expiresAt *time.Time, maxUses int, status string) membershipmodel.MembershipRedeemCode {
	t.Helper()

	code := normalizeCode(plainCode)
	record := membershipmodel.MembershipRedeemCode{
		CodeHash:     hashCode(code),
		CodeSuffix:   suffixOf(code, 6),
		Plan:         "month",
		DurationDays: durationDays,
		ExpiresAt:    expiresAt,
		MaxUses:      maxUses,
		UsedUses:     0,
		Status:       status,
	}
	if err := db.Create(&record).Error; err != nil {
		t.Fatalf("seed redeem code: %v", err)
	}
	return record
}

func TestRedeemCodeServiceRedeemSuccessAndRepeat(t *testing.T) {
	t.Parallel()

	db := setupRedeemTestDB(t)
	svc := NewRedeemCodeService(db, "")
	user := &usermodel.User{ID: 1, MiniProgramID: 10}

	code := "TEST-CODE-001"
	seedRedeemCode(t, db, code, 30, nil, 1, "active")

	res, err := svc.Redeem(context.Background(), user, code, "127.0.0.1", "ut")
	if err != nil {
		t.Fatalf("redeem success: %v", err)
	}
	if res == nil || res.Extended {
		t.Fatalf("first redeem should create membership and extended=false")
	}

	var membership usermodel.UserMembership
	if err := db.Where("mini_program_id = ? AND user_id = ?", user.MiniProgramID, user.ID).First(&membership).Error; err != nil {
		t.Fatalf("query membership: %v", err)
	}
	if membership.Status != "active" {
		t.Fatalf("membership status=%s, want=active", membership.Status)
	}

	var storedCode membershipmodel.MembershipRedeemCode
	if err := db.Where("code_hash = ?", hashCode(normalizeCode(code))).First(&storedCode).Error; err != nil {
		t.Fatalf("query redeem code: %v", err)
	}
	if storedCode.UsedUses != 1 {
		t.Fatalf("used_uses=%d, want=1", storedCode.UsedUses)
	}

	_, err = svc.Redeem(context.Background(), user, code, "127.0.0.1", "ut")
	if !errors.Is(err, ErrRedeemCodeUsedUp) {
		t.Fatalf("repeat redeem err=%v, want ErrRedeemCodeUsedUp", err)
	}
}

func TestRedeemCodeServiceRedeemExpiredCode(t *testing.T) {
	t.Parallel()

	db := setupRedeemTestDB(t)
	svc := NewRedeemCodeService(db, "")
	user := &usermodel.User{ID: 2, MiniProgramID: 10}

	expired := time.Now().Add(-1 * time.Hour)
	code := "TEST-CODE-EXPIRED"
	seedRedeemCode(t, db, code, 30, &expired, 1, "active")

	_, err := svc.Redeem(context.Background(), user, code, "127.0.0.1", "ut")
	if !errors.Is(err, ErrRedeemCodeExpired) {
		t.Fatalf("redeem expired err=%v, want ErrRedeemCodeExpired", err)
	}
}

func TestRedeemCodeServiceRedeemInvalidCode(t *testing.T) {
	t.Parallel()

	db := setupRedeemTestDB(t)
	svc := NewRedeemCodeService(db, "")
	user := &usermodel.User{ID: 3, MiniProgramID: 10}

	_, err := svc.Redeem(context.Background(), user, "NOT-FOUND-CODE", "127.0.0.1", "ut")
	if !errors.Is(err, ErrRedeemCodeInvalid) {
		t.Fatalf("redeem invalid err=%v, want ErrRedeemCodeInvalid", err)
	}
}

func TestRedeemCodeServiceRedeemExtendsActiveMembership(t *testing.T) {
	t.Parallel()

	db := setupRedeemTestDB(t)
	svc := NewRedeemCodeService(db, "")
	user := &usermodel.User{ID: 4, MiniProgramID: 10}

	firstCode := "TEST-CODE-A"
	secondCode := "TEST-CODE-B"
	seedRedeemCode(t, db, firstCode, 10, nil, 1, "active")
	seedRedeemCode(t, db, secondCode, 15, nil, 1, "active")

	firstRes, err := svc.Redeem(context.Background(), user, firstCode, "127.0.0.1", "ut")
	if err != nil {
		t.Fatalf("first redeem: %v", err)
	}
	secondRes, err := svc.Redeem(context.Background(), user, secondCode, "127.0.0.1", "ut")
	if err != nil {
		t.Fatalf("second redeem: %v", err)
	}
	if secondRes == nil || !secondRes.Extended {
		t.Fatalf("second redeem should extend existing membership")
	}
	if !secondRes.EndsAt.After(firstRes.EndsAt) {
		t.Fatalf("second ends_at=%s should be after first ends_at=%s", secondRes.EndsAt, firstRes.EndsAt)
	}
}