package store

import (
	"context"
	"encoding/json"
	"errors"
	"fmt"
	"strconv"
	"strings"
	"time"

	"github.com/jackc/pgx/v5"
)

const (
	BillingSettlementBatchSize   = 50
	BillingSettlementLockTimeout = 120 * time.Second
	BillingSettlementMaxAttempts = 20
)

var ErrBillingSettlementNotRetryable = errors.New("billing settlement is not retryable")

type BillingSettlement struct {
	ID                 string         `json:"id"`
	TaskID             string         `json:"taskId"`
	Action             string         `json:"action"`
	Amount             float64        `json:"amount"`
	Currency           string         `json:"currency"`
	Status             string         `json:"status"`
	Attempts           int            `json:"attempts"`
	NextAttemptAt      time.Time      `json:"nextAttemptAt"`
	LockedBy           string         `json:"lockedBy,omitempty"`
	LockedAt           string         `json:"lockedAt,omitempty"`
	LastErrorCode      string         `json:"lastErrorCode,omitempty"`
	LastErrorMessage   string         `json:"lastErrorMessage,omitempty"`
	ManualReviewReason string         `json:"manualReviewReason,omitempty"`
	PricingSnapshot    map[string]any `json:"pricingSnapshot,omitempty"`
	Payload            map[string]any `json:"payload,omitempty"`
	CompletedAt        string         `json:"completedAt,omitempty"`
	CreatedAt          time.Time      `json:"createdAt"`
	UpdatedAt          time.Time      `json:"updatedAt"`
	LockToken          string         `json:"-"`
	amountExact        string
}

type BillingSettlementListFilter struct {
	Status   string
	Action   string
	Page     int
	PageSize int
}

type BillingSettlementListResult struct {
	Items    []BillingSettlement `json:"items"`
	Total    int                 `json:"total"`
	Page     int                 `json:"page"`
	PageSize int                 `json:"pageSize"`
}

type BillingMetricsSnapshot struct {
	SettlementBacklog   int64
	SettlementDelaySecs float64
	ManualReview        int64
	OrphanFrozen        int64
	PricingUnavailable  int64
}

func (s *Store) BillingMetrics(ctx context.Context) (BillingMetricsSnapshot, error) {
	var snapshot BillingMetricsSnapshot
	err := s.pool.QueryRow(ctx, `
WITH open_outbox AS (
  SELECT created_at
  FROM settlement_outbox
  WHERE status IN ('pending', 'processing', 'retryable_failed')
), active_reservations AS (
  SELECT reserve.account_id, COALESCE(SUM(reserve.amount), 0) AS amount
  FROM gateway_wallet_transactions reserve
  WHERE reserve.transaction_type = 'reserve'
    AND NOT EXISTS (
      SELECT 1 FROM gateway_wallet_transactions release
      WHERE release.account_id = reserve.account_id
        AND release.transaction_type = 'release'
        AND release.idempotency_key = reserve.idempotency_key || ':release'
    )
  GROUP BY reserve.account_id
)
SELECT
  (SELECT COUNT(*) FROM open_outbox),
  COALESCE((SELECT EXTRACT(EPOCH FROM now() - MIN(created_at)) FROM open_outbox), 0),
  (SELECT COUNT(*) FROM gateway_tasks WHERE billing_status = 'manual_review'),
  (SELECT COUNT(*) FROM gateway_wallet_accounts account
   LEFT JOIN active_reservations reservation ON reservation.account_id = account.id
   WHERE account.frozen_balance <> COALESCE(reservation.amount, 0)),
  (SELECT COUNT(*) FROM gateway_tasks WHERE error_code = 'pricing_unavailable')`).Scan(
		&snapshot.SettlementBacklog,
		&snapshot.SettlementDelaySecs,
		&snapshot.ManualReview,
		&snapshot.OrphanFrozen,
		&snapshot.PricingUnavailable,
	)
	return snapshot, err
}

func (s *Store) ClaimBillingSettlements(ctx context.Context, workerID string, limit int, staleAfter time.Duration) ([]BillingSettlement, error) {
	if limit <= 0 || limit > BillingSettlementBatchSize {
		limit = BillingSettlementBatchSize
	}
	if staleAfter <= 0 {
		staleAfter = BillingSettlementLockTimeout
	}
	rows, err := s.pool.Query(ctx, `
WITH picked AS (
  SELECT id
  FROM settlement_outbox
  WHERE (
      status IN ('pending', 'retryable_failed')
      AND next_attempt_at <= now()
    )
    OR (
      status = 'processing'
      AND locked_at < now() - ($3::int * interval '1 second')
    )
  ORDER BY next_attempt_at ASC, created_at ASC
  LIMIT $2
  FOR UPDATE SKIP LOCKED
)
UPDATE settlement_outbox outbox
SET status = 'processing',
    attempts = outbox.attempts + 1,
    locked_by = $1,
    lock_token = gen_random_uuid(),
    locked_at = now(),
    updated_at = now()
FROM picked
WHERE outbox.id = picked.id
RETURNING outbox.id::text, outbox.task_id::text, outbox.action, outbox.amount::text,
          outbox.currency, outbox.status, outbox.attempts, outbox.next_attempt_at,
          COALESCE(outbox.locked_by, ''), COALESCE(outbox.lock_token::text, ''),
          COALESCE(outbox.locked_at::text, ''), COALESCE(outbox.last_error_code, ''),
          COALESCE(outbox.last_error_message, ''), COALESCE(outbox.manual_review_reason, ''),
          outbox.pricing_snapshot, outbox.payload, COALESCE(outbox.completed_at::text, ''),
          outbox.created_at, outbox.updated_at`,
		workerID, limit, int(staleAfter/time.Second))
	if err != nil {
		return nil, err
	}
	defer rows.Close()
	items := make([]BillingSettlement, 0)
	for rows.Next() {
		item, err := scanBillingSettlement(rows)
		if err != nil {
			return nil, err
		}
		items = append(items, item)
	}
	return items, rows.Err()
}

func (s *Store) ProcessBillingSettlement(ctx context.Context, settlement BillingSettlement) error {
	return pgx.BeginFunc(ctx, s.pool, func(tx pgx.Tx) error {
		var action string
		var amount string
		var currency string
		var taskID string
		var taskStatus string
		var gatewayUserID string
		var gatewayTenantID string
		var userID string
		var tenantID string
		var tenantKey string
		err := tx.QueryRow(ctx, `
SELECT outbox.action, outbox.amount::text, outbox.currency, outbox.task_id::text,
       task.status, COALESCE(task.gateway_user_id::text, ''),
       COALESCE(task.gateway_tenant_id::text, ''), task.user_id,
       COALESCE(task.tenant_id, ''), COALESCE(task.tenant_key, '')
FROM settlement_outbox outbox
JOIN gateway_tasks task ON task.id = outbox.task_id
WHERE outbox.id = $1::uuid
  AND outbox.status = 'processing'
  AND outbox.lock_token = $2::uuid
FOR UPDATE OF outbox, task`, settlement.ID, settlement.LockToken).Scan(
			&action, &amount, &currency, &taskID, &taskStatus, &gatewayUserID,
			&gatewayTenantID, &userID, &tenantID, &tenantKey,
		)
		if err != nil {
			return err
		}
		if _, err := tx.Exec(ctx, `
UPDATE gateway_tasks
SET billing_status = 'processing', billing_updated_at = now(), updated_at = now()
WHERE id = $1::uuid`, taskID); err != nil {
			return err
		}
		switch action {
		case "settle":
			if taskStatus != "succeeded" {
				return fmt.Errorf("settle action requires succeeded task")
			}
			if err := settleBillingOutboxTx(ctx, tx, taskID, gatewayUserID, gatewayTenantID, userID, tenantID, tenantKey, currency, amount); err != nil {
				return err
			}
			return completeBillingOutboxTx(ctx, tx, settlement.ID, settlement.LockToken, taskID, "settled")
		case "release":
			if err := releaseBillingOutboxTx(ctx, tx, taskID, gatewayUserID, gatewayTenantID, currency); err != nil {
				return err
			}
			return completeBillingOutboxTx(ctx, tx, settlement.ID, settlement.LockToken, taskID, "released")
		default:
			return fmt.Errorf("unsupported billing settlement action %q", action)
		}
	})
}

func settleBillingOutboxTx(
	ctx context.Context,
	tx pgx.Tx,
	taskID string,
	gatewayUserID string,
	gatewayTenantID string,
	userID string,
	tenantID string,
	tenantKey string,
	currency string,
	amount string,
) error {
	if gatewayUserID == "" {
		return fmt.Errorf("task %s has no gateway wallet user", taskID)
	}
	if _, err := tx.Exec(ctx, `
INSERT INTO gateway_wallet_accounts (
  gateway_tenant_id, gateway_user_id, tenant_id, tenant_key, user_id, currency
)
VALUES (NULLIF($1, '')::uuid, $2::uuid, NULLIF($3, ''), NULLIF($4, ''), NULLIF($5, ''), $6)
ON CONFLICT (gateway_user_id, currency) DO NOTHING`,
		gatewayTenantID, gatewayUserID, tenantID, tenantKey, userID, currency); err != nil {
		return err
	}
	if err := ensureWalletAccountAuditGuard(ctx, tx, gatewayUserID, currency); err != nil {
		return err
	}
	var accountID string
	var balanceBefore string
	var frozenBefore string
	if err := tx.QueryRow(ctx, `
SELECT id::text, balance::text, frozen_balance::text
FROM gateway_wallet_accounts
WHERE gateway_user_id = $1::uuid AND currency = $2
FOR UPDATE`, gatewayUserID, currency).Scan(&accountID, &balanceBefore, &frozenBefore); err != nil {
		return err
	}
	var alreadySettled bool
	if err := tx.QueryRow(ctx, `
SELECT EXISTS (
  SELECT 1 FROM gateway_wallet_transactions
  WHERE account_id = $1::uuid AND idempotency_key = $2
)`, accountID, billingIdempotencyKey(taskID)).Scan(&alreadySettled); err != nil {
		return err
	}
	if alreadySettled {
		return nil
	}

	var reservationKey string
	var reservedAmount string
	if err := tx.QueryRow(ctx, `
SELECT COALESCE(reserve.idempotency_key, ''), reserve.amount::text
FROM gateway_wallet_transactions reserve
WHERE reserve.account_id = $1::uuid
  AND reserve.reference_type = 'gateway_task'
  AND reserve.reference_id = $2
  AND reserve.transaction_type = 'reserve'
  AND NOT EXISTS (
    SELECT 1 FROM gateway_wallet_transactions release
    WHERE release.account_id = reserve.account_id
      AND release.transaction_type = 'release'
      AND release.idempotency_key = reserve.idempotency_key || ':release'
  )
ORDER BY reserve.created_at DESC
LIMIT 1`, accountID, taskID).Scan(&reservationKey, &reservedAmount); errors.Is(err, pgx.ErrNoRows) {
		reservationKey = ""
		reservedAmount = "0"
	} else if err != nil {
		return err
	}

	var balanceAfter string
	var frozenAfter string
	err := tx.QueryRow(ctx, `
UPDATE gateway_wallet_accounts
SET balance = balance - $2::numeric,
    total_spent = total_spent + $2::numeric,
    frozen_balance = GREATEST(0, frozen_balance - $3::numeric),
    updated_at = now()
WHERE id = $1::uuid
  AND balance - frozen_balance + $3::numeric >= $2::numeric
RETURNING balance::text, frozen_balance::text`,
		accountID, amount, reservedAmount).Scan(&balanceAfter, &frozenAfter)
	if errors.Is(err, pgx.ErrNoRows) {
		return fmt.Errorf("%w: task %s settlement amount exceeds spendable balance", ErrInsufficientWalletBalance, taskID)
	}
	if err != nil {
		return err
	}

	var reservedPositive bool
	if err := tx.QueryRow(ctx, `SELECT $1::numeric > 0`, reservedAmount).Scan(&reservedPositive); err != nil {
		return err
	}
	if reservedPositive {
		releaseMetadata, _ := json.Marshal(map[string]any{
			"taskId": taskID, "reason": "task_billing_settled",
			"reserved": reservedAmount, "frozenBefore": frozenBefore, "frozenAfter": frozenAfter,
		})
		if _, err := tx.Exec(ctx, `
INSERT INTO gateway_wallet_transactions (
  account_id, gateway_tenant_id, gateway_user_id, direction, transaction_type,
  amount, balance_before, balance_after, idempotency_key, reference_type, reference_id, metadata
)
VALUES (
  $1::uuid, NULLIF($2, '')::uuid, $3::uuid, 'credit', 'release',
  $4::numeric, $5::numeric, $5::numeric, $6, 'gateway_task', $7, $8::jsonb
)
ON CONFLICT (account_id, idempotency_key) WHERE idempotency_key IS NOT NULL DO NOTHING`,
			accountID, gatewayTenantID, gatewayUserID, reservedAmount, balanceBefore,
			billingReservationReleaseIdempotencyKey(reservationKey), taskID, string(releaseMetadata)); err != nil {
			return err
		}
	}
	metadata, _ := json.Marshal(map[string]any{
		"taskId": taskID, "reservedAmount": reservedAmount,
		"frozenBefore": frozenBefore, "frozenAfter": frozenAfter,
	})
	_, err = tx.Exec(ctx, `
INSERT INTO gateway_wallet_transactions (
  account_id, gateway_tenant_id, gateway_user_id, direction, transaction_type,
  amount, balance_before, balance_after, idempotency_key, reference_type, reference_id, metadata
)
VALUES (
  $1::uuid, NULLIF($2, '')::uuid, $3::uuid, 'debit', 'task_billing',
  $4::numeric, $5::numeric, $6::numeric, $7, 'gateway_task', $8, $9::jsonb
)
ON CONFLICT (account_id, idempotency_key) WHERE idempotency_key IS NOT NULL DO NOTHING`,
		accountID, gatewayTenantID, gatewayUserID, amount, balanceBefore, balanceAfter,
		billingIdempotencyKey(taskID), taskID, string(metadata))
	return err
}

func releaseBillingOutboxTx(ctx context.Context, tx pgx.Tx, taskID string, gatewayUserID string, gatewayTenantID string, currency string) error {
	if gatewayUserID == "" {
		return nil
	}
	var accountID string
	var balance string
	var frozenBefore string
	err := tx.QueryRow(ctx, `
SELECT id::text, balance::text, frozen_balance::text
FROM gateway_wallet_accounts
WHERE gateway_user_id = $1::uuid AND currency = $2
FOR UPDATE`, gatewayUserID, currency).Scan(&accountID, &balance, &frozenBefore)
	if errors.Is(err, pgx.ErrNoRows) {
		return nil
	}
	if err != nil {
		return err
	}
	var reservationKey string
	var reservedAmount string
	err = tx.QueryRow(ctx, `
SELECT COALESCE(reserve.idempotency_key, ''), reserve.amount::text
FROM gateway_wallet_transactions reserve
WHERE reserve.account_id = $1::uuid
  AND reserve.reference_type = 'gateway_task'
  AND reserve.reference_id = $2
  AND reserve.transaction_type = 'reserve'
  AND NOT EXISTS (
    SELECT 1 FROM gateway_wallet_transactions release
    WHERE release.account_id = reserve.account_id
      AND release.transaction_type = 'release'
      AND release.idempotency_key = reserve.idempotency_key || ':release'
  )
ORDER BY reserve.created_at DESC
LIMIT 1`, accountID, taskID).Scan(&reservationKey, &reservedAmount)
	if errors.Is(err, pgx.ErrNoRows) {
		return nil
	}
	if err != nil {
		return err
	}
	var frozenAfter string
	if err := tx.QueryRow(ctx, `
UPDATE gateway_wallet_accounts
SET frozen_balance = frozen_balance - $2::numeric,
    updated_at = now()
WHERE id = $1::uuid
  AND frozen_balance >= $2::numeric
RETURNING frozen_balance::text`, accountID, reservedAmount).Scan(&frozenAfter); err != nil {
		return err
	}
	metadata, _ := json.Marshal(map[string]any{
		"taskId": taskID, "reason": "task_terminal_release",
		"reserved": reservedAmount, "frozenBefore": frozenBefore, "frozenAfter": frozenAfter,
	})
	_, err = tx.Exec(ctx, `
INSERT INTO gateway_wallet_transactions (
  account_id, gateway_tenant_id, gateway_user_id, direction, transaction_type,
  amount, balance_before, balance_after, idempotency_key, reference_type, reference_id, metadata
)
VALUES (
  $1::uuid, NULLIF($2, '')::uuid, $3::uuid, 'credit', 'release',
  $4::numeric, $5::numeric, $5::numeric, $6, 'gateway_task', $7, $8::jsonb
)
ON CONFLICT (account_id, idempotency_key) WHERE idempotency_key IS NOT NULL DO NOTHING`,
		accountID, gatewayTenantID, gatewayUserID, reservedAmount, balance,
		billingReservationReleaseIdempotencyKey(reservationKey), taskID, string(metadata))
	return err
}

func completeBillingOutboxTx(ctx context.Context, tx pgx.Tx, settlementID string, lockToken string, taskID string, billingStatus string) error {
	if _, err := tx.Exec(ctx, `
UPDATE gateway_tasks
SET billing_status = $2,
    reservation_amount = 0,
    billing_updated_at = now(),
    billing_settled_at = CASE WHEN $2 = 'settled' THEN now() ELSE billing_settled_at END,
    updated_at = now()
WHERE id = $1::uuid`, taskID, billingStatus); err != nil {
		return err
	}
	if _, err := tx.Exec(ctx, `
INSERT INTO gateway_task_events (task_id, seq, event_type, status, phase, progress, message, payload, simulated)
SELECT task.id,
       COALESCE((SELECT MAX(event.seq) + 1 FROM gateway_task_events event WHERE event.task_id = task.id), 1),
       CASE WHEN $2 = 'settled' THEN 'task.billing.settled' ELSE 'task.billing.released' END,
       task.status,
       NULL,
       0,
       NULL,
       '{}'::jsonb,
       task.run_mode = 'simulation'
FROM gateway_tasks task
WHERE task.id = $1::uuid`, taskID, billingStatus); err != nil {
		return err
	}
	tag, err := tx.Exec(ctx, `
UPDATE settlement_outbox
SET status = 'completed',
    completed_at = now(),
    locked_by = NULL,
    lock_token = NULL,
    locked_at = NULL,
    last_error_code = NULL,
    last_error_message = NULL,
    updated_at = now()
WHERE id = $1::uuid
  AND status = 'processing'
  AND lock_token = $2::uuid`, settlementID, lockToken)
	if err != nil {
		return err
	}
	if tag.RowsAffected() != 1 {
		return pgx.ErrNoRows
	}
	return nil
}

func (s *Store) MarkBillingSettlementFailed(ctx context.Context, settlement BillingSettlement, code string, message string, delay time.Duration) error {
	if delay < time.Second {
		delay = time.Second
	}
	if delay > 15*time.Minute {
		delay = 15 * time.Minute
	}
	manualReview := settlement.Attempts >= BillingSettlementMaxAttempts
	status := "retryable_failed"
	taskStatus := "retryable_failed"
	manualReason := ""
	if manualReview {
		status = "manual_review"
		taskStatus = "manual_review"
		manualReason = "maximum settlement attempts exceeded"
	}
	return pgx.BeginFunc(ctx, s.pool, func(tx pgx.Tx) error {
		tag, err := tx.Exec(ctx, `
UPDATE settlement_outbox
SET status = $3,
    next_attempt_at = now() + ($4::int * interval '1 second'),
    locked_by = NULL,
    lock_token = NULL,
    locked_at = NULL,
    last_error_code = NULLIF($5, ''),
    last_error_message = NULLIF($6, ''),
    manual_review_reason = NULLIF($7, ''),
    updated_at = now()
WHERE id = $1::uuid
  AND lock_token = $2::uuid
  AND status = 'processing'`,
			settlement.ID, settlement.LockToken, status, int(delay/time.Second), code, message, manualReason)
		if err != nil {
			return err
		}
		if tag.RowsAffected() != 1 {
			return pgx.ErrNoRows
		}
		_, err = tx.Exec(ctx, `
UPDATE gateway_tasks
SET billing_status = $2,
    billing_updated_at = now(),
    updated_at = now()
WHERE id = $1::uuid`, settlement.TaskID, taskStatus)
		return err
	})
}

func (s *Store) ListBillingSettlements(ctx context.Context, filter BillingSettlementListFilter) (BillingSettlementListResult, error) {
	page := filter.Page
	if page <= 0 {
		page = 1
	}
	pageSize := filter.PageSize
	if pageSize <= 0 {
		pageSize = 50
	}
	if pageSize > 100 {
		pageSize = 100
	}
	status := strings.TrimSpace(filter.Status)
	action := strings.TrimSpace(filter.Action)
	var total int
	if err := s.pool.QueryRow(ctx, `
SELECT count(*)
FROM settlement_outbox
WHERE (NULLIF($1, '') IS NULL OR status = $1)
  AND (NULLIF($2, '') IS NULL OR action = $2)`, status, action).Scan(&total); err != nil {
		return BillingSettlementListResult{}, err
	}
	rows, err := s.pool.Query(ctx, `
SELECT id::text, task_id::text, action, amount::text, currency, status, attempts,
       next_attempt_at, COALESCE(locked_by, ''), COALESCE(lock_token::text, ''),
       COALESCE(locked_at::text, ''), COALESCE(last_error_code, ''),
       COALESCE(last_error_message, ''), COALESCE(manual_review_reason, ''),
       pricing_snapshot, payload, COALESCE(completed_at::text, ''), created_at, updated_at
FROM settlement_outbox
WHERE (NULLIF($1, '') IS NULL OR status = $1)
  AND (NULLIF($2, '') IS NULL OR action = $2)
ORDER BY created_at DESC
LIMIT $3 OFFSET $4`, status, action, pageSize, (page-1)*pageSize)
	if err != nil {
		return BillingSettlementListResult{}, err
	}
	defer rows.Close()
	items := make([]BillingSettlement, 0)
	for rows.Next() {
		item, err := scanBillingSettlement(rows)
		if err != nil {
			return BillingSettlementListResult{}, err
		}
		items = append(items, item)
	}
	if err := rows.Err(); err != nil {
		return BillingSettlementListResult{}, err
	}
	return BillingSettlementListResult{Items: items, Total: total, Page: page, PageSize: pageSize}, nil
}

func (s *Store) RetryBillingSettlementTx(ctx context.Context, tx Tx, id string, idempotencyKeyHash string) (BillingSettlement, bool, error) {
	current, err := scanBillingSettlement(tx.QueryRow(ctx, `
SELECT id::text, task_id::text, action, amount::text, currency, status, attempts,
       next_attempt_at, COALESCE(locked_by, ''), COALESCE(lock_token::text, ''),
       COALESCE(locked_at::text, ''), COALESCE(last_error_code, ''),
       COALESCE(last_error_message, ''), COALESCE(manual_review_reason, ''),
       pricing_snapshot, payload, COALESCE(completed_at::text, ''), created_at, updated_at
FROM settlement_outbox
WHERE id = $1::uuid
FOR UPDATE`, id))
	if err != nil {
		return BillingSettlement{}, false, err
	}
	var recordedHash string
	if err := tx.QueryRow(ctx, `
SELECT COALESCE(retry_idempotency_key_hash, '')
FROM settlement_outbox
WHERE id = $1::uuid`, id).Scan(&recordedHash); err != nil {
		return BillingSettlement{}, false, err
	}
	if recordedHash != "" && recordedHash == idempotencyKeyHash {
		return current, true, nil
	}
	if current.Status != "retryable_failed" && current.Status != "manual_review" {
		return BillingSettlement{}, false, ErrBillingSettlementNotRetryable
	}
	item, err := scanBillingSettlement(tx.QueryRow(ctx, `
UPDATE settlement_outbox
SET status = 'pending',
    next_attempt_at = now(),
    locked_by = NULL,
    lock_token = NULL,
    locked_at = NULL,
    manual_review_reason = NULL,
    retry_idempotency_key_hash = $2,
    retry_requested_at = now(),
    updated_at = now()
WHERE id = $1::uuid
  AND status IN ('retryable_failed', 'manual_review')
RETURNING id::text, task_id::text, action, amount::text, currency, status, attempts,
          next_attempt_at, COALESCE(locked_by, ''), COALESCE(lock_token::text, ''),
          COALESCE(locked_at::text, ''), COALESCE(last_error_code, ''),
          COALESCE(last_error_message, ''), COALESCE(manual_review_reason, ''),
          pricing_snapshot, payload, COALESCE(completed_at::text, ''), created_at, updated_at`, id, idempotencyKeyHash))
	if err != nil {
		return BillingSettlement{}, false, err
	}
	if _, err := tx.Exec(ctx, `
UPDATE gateway_tasks
SET billing_status = 'pending', billing_updated_at = now(), updated_at = now()
WHERE id = $1::uuid`, item.TaskID); err != nil {
		return BillingSettlement{}, false, err
	}
	return item, false, nil
}

func scanBillingSettlement(scanner taskScanner) (BillingSettlement, error) {
	var item BillingSettlement
	var pricingSnapshotBytes []byte
	var payloadBytes []byte
	if err := scanner.Scan(
		&item.ID, &item.TaskID, &item.Action, &item.amountExact, &item.Currency,
		&item.Status, &item.Attempts, &item.NextAttemptAt, &item.LockedBy, &item.LockToken,
		&item.LockedAt, &item.LastErrorCode, &item.LastErrorMessage, &item.ManualReviewReason,
		&pricingSnapshotBytes, &payloadBytes, &item.CompletedAt, &item.CreatedAt, &item.UpdatedAt,
	); err != nil {
		return BillingSettlement{}, err
	}
	item.Amount, _ = strconv.ParseFloat(item.amountExact, 64)
	item.PricingSnapshot = decodeObject(pricingSnapshotBytes)
	item.Payload = decodeObject(payloadBytes)
	return item, nil
}