package repository

import (
	"database/sql"
	"errors"
	"fmt"
	"strings"

	"cmautobuy/admin/model"
)

// InnerCodeSybSnapshot 是本地顺运宝明细用于解析货运单 stock id 的最小快照。
type InnerCodeSybSnapshot struct {
	OrderNumber string
	SybData     string
}

// InnerCodeListFilter 是独立页面可组合的查询条件。
type InnerCodeListFilter struct {
	BusinessDate string
	Status       string
	Keyword      string
}

// InnerCodeStatusCounts 是当前业务日期的底栏摘要。
type InnerCodeStatusCounts struct {
	Total      int
	Ready      int
	NeedsCheck int
}

// InnerCodeImportOutcome 说明幂等导入是新增还是更新。
type InnerCodeImportOutcome string

const (
	InnerCodeImportCreated InnerCodeImportOutcome = "created"
	InnerCodeImportUpdated InnerCodeImportOutcome = "updated"
)

// UpsertInnerCodeImportRow 按已确认业务键写入一行。
// 必须在事务中调用；先锁定业务键，避免另一个唯一键冲突时更新错行。
func UpsertInnerCodeImportRow(tx *sql.Tx, row model.InnerCodeImportRow, now string) (InnerCodeImportOutcome, error) {
	var id int64
	err := tx.QueryRow(`
		SELECT id FROM syb_inner_code_records
		 WHERE business_date=? AND order_number=? AND stall=? AND spec_key=?
		 FOR UPDATE`, row.BusinessDate, row.OrderNumber, row.Stall, row.SpecKey).Scan(&id)
	if err != nil && !errors.Is(err, sql.ErrNoRows) {
		return "", fmt.Errorf("锁定档口入库码业务键失败: %w", err)
	}
	if errors.Is(err, sql.ErrNoRows) {
		_, err = tx.Exec(`
			INSERT INTO syb_inner_code_records (
				business_date,source_row,print_sequence,order_number,shop_name,stall,
				spec_raw,spec_key,inner_code,source_duplicate_count,status,
				created_by_user_id,created_at,updated_at
			) VALUES (?,?,?,?,?,?,?,?,?,?,'pending',?,?,?)`,
			row.BusinessDate, row.SourceRow, nullablePositiveInt(row.PrintSequence), row.OrderNumber,
			nullableString(row.ShopName), row.Stall, row.SpecRaw, row.SpecKey, row.InnerCode,
			row.SourceDuplicateCount, row.CreatedByUserID, now, now)
		if err != nil {
			return "", fmt.Errorf("新增档口入库码记录失败: %w", err)
		}
		return InnerCodeImportCreated, nil
	}

	_, err = tx.Exec(`
		UPDATE syb_inner_code_records
		   SET source_row=?,print_sequence=?,shop_name=?,spec_raw=?,inner_code=?,
		       source_duplicate_count=?,
		       status=CASE WHEN status IN ('updated','already_filled','applying','needs_check')
		                   THEN status ELSE 'pending' END,
		       stock_id=CASE WHEN status IN ('updated','already_filled','applying','needs_check') THEN stock_id ELSE NULL END,
		       detail_id=CASE WHEN status IN ('updated','already_filled','applying','needs_check') THEN detail_id ELSE NULL END,
		       syb_spec=CASE WHEN status IN ('updated','already_filled','applying','needs_check') THEN syb_spec ELSE NULL END,
		       syb_sku=CASE WHEN status IN ('updated','already_filled','applying','needs_check') THEN syb_sku ELSE NULL END,
		       syb_variation_sku=CASE WHEN status IN ('updated','already_filled','applying','needs_check') THEN syb_variation_sku ELSE NULL END,
		       purchase_platform=CASE WHEN status IN ('updated','already_filled','applying','needs_check') THEN purchase_platform ELSE NULL END,
		       purchase_code=CASE WHEN status IN ('updated','already_filled','applying','needs_check') THEN purchase_code ELSE NULL END,
		       remote_inner_code=CASE WHEN status IN ('updated','already_filled','applying','needs_check') THEN remote_inner_code ELSE NULL END,
		       result_message=CASE WHEN status IN ('updated','already_filled','applying','needs_check') THEN result_message ELSE NULL END,
		       planned_at=CASE WHEN status IN ('updated','already_filled','applying','needs_check') THEN planned_at ELSE NULL END,
		       updated_at=?
		 WHERE id=?`,
		row.SourceRow, nullablePositiveInt(row.PrintSequence), nullableString(row.ShopName), row.SpecRaw,
		row.InnerCode, row.SourceDuplicateCount, now, id)
	if err != nil {
		return "", fmt.Errorf("更新档口入库码导入记录失败: %w", err)
	}
	return InnerCodeImportUpdated, nil
}

// ListInnerCodeRecordsForPlanning 返回某日允许重新规划的记录。
func ListInnerCodeRecordsForPlanning(q Execer, businessDate string) ([]model.InnerCodeRecord, error) {
	rows, err := q.Query(`
		SELECT id,business_date,source_row,COALESCE(print_sequence,0),order_number,
		       COALESCE(shop_name,''),stall,spec_raw,spec_key,inner_code,source_duplicate_count,
		       status,COALESCE(result_message,''),created_by_user_id,created_at,updated_at
		  FROM syb_inner_code_records
		 WHERE business_date=? AND status IN ('pending','ready','skipped','failed')
		 ORDER BY source_row,id`, businessDate)
	if err != nil {
		return nil, fmt.Errorf("查询待规划档口入库码失败: %w", err)
	}
	defer rows.Close()
	result := make([]model.InnerCodeRecord, 0)
	for rows.Next() {
		var row model.InnerCodeRecord
		if err := rows.Scan(&row.ID, &row.BusinessDate, &row.SourceRow, &row.PrintSequence,
			&row.OrderNumber, &row.ShopName, &row.Stall, &row.SpecRaw, &row.SpecKey,
			&row.InnerCode, &row.SourceDuplicateCount, &row.Status, &row.ResultMessage,
			&row.CreatedByUserID, &row.CreatedAt, &row.UpdatedAt); err != nil {
			return nil, fmt.Errorf("读取待规划档口入库码失败: %w", err)
		}
		result = append(result, row)
	}
	if err := rows.Err(); err != nil {
		return nil, fmt.Errorf("遍历待规划档口入库码失败: %w", err)
	}
	return result, nil
}

// ListInnerCodeSybSnapshots 查询订单号对应的本地 SYB 原始快照。
func ListInnerCodeSybSnapshots(q Execer, orderNumbers []string) ([]InnerCodeSybSnapshot, error) {
	if len(orderNumbers) == 0 {
		return nil, nil
	}
	placeholders := make([]string, len(orderNumbers))
	args := make([]any, len(orderNumbers))
	for index, orderNumber := range orderNumbers {
		placeholders[index] = "?"
		args[index] = orderNumber
	}
	rows, err := q.Query(`SELECT order_no,syb_data FROM syb_orders WHERE order_no IN (`+
		strings.Join(placeholders, ",")+`) ORDER BY order_no,syb_id`, args...)
	if err != nil {
		return nil, fmt.Errorf("查询档口入库码对应顺运宝快照失败: %w", err)
	}
	defer rows.Close()
	result := make([]InnerCodeSybSnapshot, 0)
	for rows.Next() {
		var row InnerCodeSybSnapshot
		if err := rows.Scan(&row.OrderNumber, &row.SybData); err != nil {
			return nil, fmt.Errorf("读取顺运宝快照失败: %w", err)
		}
		result = append(result, row)
	}
	if err := rows.Err(); err != nil {
		return nil, fmt.Errorf("遍历顺运宝快照失败: %w", err)
	}
	return result, nil
}

// SaveInnerCodePlans 在同一事务中保存一批只读规划结果。
func SaveInnerCodePlans(db *sql.DB, plans []model.InnerCodeRecord, plannedAt string) error {
	tx, err := db.Begin()
	if err != nil {
		return fmt.Errorf("开始保存档口入库码规划事务失败: %w", err)
	}
	defer tx.Rollback()
	for _, plan := range plans {
		result, err := tx.Exec(`
			UPDATE syb_inner_code_records
			   SET stock_id=?,detail_id=?,syb_spec=?,syb_sku=?,syb_variation_sku=?,
			       purchase_platform=?,purchase_code=?,remote_inner_code=?,status=?,
			       result_message=?,planned_at=?,updated_at=?
			 WHERE id=? AND status IN ('pending','ready','skipped','failed')`,
			nullablePositiveInt64(plan.StockID), nullablePositiveInt64(plan.DetailID),
			nullableString(plan.SybSpec), nullableString(plan.SybSKU), nullableString(plan.SybVariationSKU),
			nullableString(plan.PurchasePlatform), nullableString(plan.PurchaseCode),
			nullableString(plan.RemoteInnerCode), plan.Status, nullableString(plan.ResultMessage),
			plannedAt, plannedAt, plan.ID)
		if err != nil {
			return fmt.Errorf("保存档口入库码记录 %d 规划失败: %w", plan.ID, err)
		}
		if affected, err := result.RowsAffected(); err != nil || affected != 1 {
			return fmt.Errorf("档口入库码记录 %d 状态已变化，规划整体未保存", plan.ID)
		}
	}
	if err := tx.Commit(); err != nil {
		return fmt.Errorf("提交档口入库码规划失败: %w", err)
	}
	return nil
}

const innerCodeListColumns = `id,business_date,source_row,COALESCE(print_sequence,0),order_number,
	COALESCE(shop_name,''),stall,spec_raw,spec_key,inner_code,source_duplicate_count,
	COALESCE(stock_id,0),COALESCE(detail_id,0),COALESCE(syb_spec,''),COALESCE(syb_sku,''),
	COALESCE(syb_variation_sku,''),COALESCE(purchase_platform,''),COALESCE(purchase_code,''),
	COALESCE(remote_inner_code,''),status,COALESCE(result_message,''),created_by_user_id,
	COALESCE(applied_by_user_id,''),COALESCE(planned_at,''),COALESCE(apply_started_at,''),
	COALESCE(applied_at,''),created_at,updated_at`

func innerCodeFilterClause(filter InnerCodeListFilter) (string, []any) {
	clauses := []string{"business_date=?"}
	args := []any{filter.BusinessDate}
	if filter.Status != "" {
		clauses = append(clauses, "status=?")
		args = append(args, filter.Status)
	}
	if filter.Keyword != "" {
		like := "%" + escapeLike(filter.Keyword) + "%"
		clauses = append(clauses, `(order_number LIKE ? ESCAPE '!' OR stall LIKE ? ESCAPE '!'
			OR spec_raw LIKE ? ESCAPE '!' OR inner_code LIKE ? ESCAPE '!')`)
		args = append(args, like, like, like, like)
	}
	return " WHERE " + strings.Join(clauses, " AND "), args
}

// ListInnerCodeRecords 分页读取独立页面记录。
func ListInnerCodeRecords(q Execer, filter InnerCodeListFilter, limit, offset int) ([]model.InnerCodeRecord, error) {
	where, args := innerCodeFilterClause(filter)
	query := `SELECT ` + innerCodeListColumns + ` FROM syb_inner_code_records` + where +
		` ORDER BY source_row,id LIMIT ? OFFSET ?`
	args = append(args, limit, offset)
	rows, err := q.Query(query, args...)
	if err != nil {
		return nil, fmt.Errorf("查询档口入库码列表失败: %w", err)
	}
	defer rows.Close()
	result := make([]model.InnerCodeRecord, 0)
	for rows.Next() {
		row, err := scanInnerCodeRecord(rows)
		if err != nil {
			return nil, err
		}
		result = append(result, row)
	}
	if err := rows.Err(); err != nil {
		return nil, fmt.Errorf("遍历档口入库码列表失败: %w", err)
	}
	return result, nil
}

// CountInnerCodeRecords 统计与列表完全相同的筛选结果。
func CountInnerCodeRecords(q Execer, filter InnerCodeListFilter) (int, error) {
	where, args := innerCodeFilterClause(filter)
	var count int
	if err := q.QueryRow(`SELECT COUNT(*) FROM syb_inner_code_records`+where, args...).Scan(&count); err != nil {
		return 0, fmt.Errorf("统计档口入库码列表失败: %w", err)
	}
	return count, nil
}

// CountInnerCodeStatuses 统计当前业务日期总量、可回写和需核对数量。
func CountInnerCodeStatuses(q Execer, businessDate string) (InnerCodeStatusCounts, error) {
	var result InnerCodeStatusCounts
	err := q.QueryRow(`SELECT COUNT(*),
		COALESCE(SUM(status='ready'),0),COALESCE(SUM(status='needs_check'),0)
		FROM syb_inner_code_records WHERE business_date=?`, businessDate).
		Scan(&result.Total, &result.Ready, &result.NeedsCheck)
	if err != nil {
		return result, fmt.Errorf("统计档口入库码状态失败: %w", err)
	}
	return result, nil
}

type innerCodeRowScanner interface {
	Scan(...any) error
}

func scanInnerCodeRecord(scanner innerCodeRowScanner) (model.InnerCodeRecord, error) {
	var row model.InnerCodeRecord
	err := scanner.Scan(&row.ID, &row.BusinessDate, &row.SourceRow, &row.PrintSequence,
		&row.OrderNumber, &row.ShopName, &row.Stall, &row.SpecRaw, &row.SpecKey,
		&row.InnerCode, &row.SourceDuplicateCount, &row.StockID, &row.DetailID,
		&row.SybSpec, &row.SybSKU, &row.SybVariationSKU, &row.PurchasePlatform,
		&row.PurchaseCode, &row.RemoteInnerCode, &row.Status, &row.ResultMessage,
		&row.CreatedByUserID, &row.AppliedByUserID, &row.PlannedAt, &row.ApplyStartedAt,
		&row.AppliedAt, &row.CreatedAt, &row.UpdatedAt)
	if err != nil {
		return row, fmt.Errorf("读取档口入库码记录失败: %w", err)
	}
	return row, nil
}

// ClaimInnerCodeForApply 原子领取一条 ready 记录。返回 claimed=false 表示状态已变化。
func ClaimInnerCodeForApply(db *sql.DB, id int64, actorUserID, now string) (*model.InnerCodeRecord, bool, error) {
	tx, err := db.Begin()
	if err != nil {
		return nil, false, fmt.Errorf("开始领取档口入库码事务失败: %w", err)
	}
	defer tx.Rollback()
	record, err := scanInnerCodeRecord(tx.QueryRow(`SELECT `+innerCodeListColumns+
		` FROM syb_inner_code_records WHERE id=? FOR UPDATE`, id))
	if errors.Is(err, sql.ErrNoRows) {
		return nil, false, nil
	}
	if err != nil {
		return nil, false, err
	}
	if record.Status != model.InnerCodeReady {
		return &record, false, nil
	}
	result, err := tx.Exec(`UPDATE syb_inner_code_records
		SET status='applying',applied_by_user_id=?,apply_started_at=?,updated_at=?
		WHERE id=? AND status='ready'`, actorUserID, now, now, id)
	if err != nil {
		return nil, false, fmt.Errorf("领取档口入库码记录失败: %w", err)
	}
	if affected, err := result.RowsAffected(); err != nil || affected != 1 {
		return &record, false, nil
	}
	if err := tx.Commit(); err != nil {
		return nil, false, fmt.Errorf("提交档口入库码领取失败: %w", err)
	}
	record.Status = model.InnerCodeApplying
	record.AppliedByUserID = actorUserID
	record.ApplyStartedAt = now
	record.UpdatedAt = now
	return &record, true, nil
}

// FinishInnerCodeApply 保存一条已领取记录的最终结果。
func FinishInnerCodeApply(q Execer, id int64, status model.InnerCodeStatus, message, remoteCode, finishedAt string) error {
	result, err := q.Exec(`UPDATE syb_inner_code_records
		SET status=?,result_message=?,remote_inner_code=?,
		    applied_at=CASE WHEN ? IN ('updated','already_filled') THEN ? ELSE applied_at END,
		    updated_at=?
		WHERE id=? AND status='applying'`, status, message, nullableString(remoteCode), status, finishedAt, finishedAt, id)
	if err != nil {
		return fmt.Errorf("保存档口入库码回写结果失败: %w", err)
	}
	if affected, err := result.RowsAffected(); err != nil || affected != 1 {
		return fmt.Errorf("档口入库码记录 %d 已不在回写中，拒绝覆盖结果", id)
	}
	return nil
}

// GetInnerCodeForRecheck 读取一条需核对记录。
func GetInnerCodeForRecheck(q Execer, id int64) (*model.InnerCodeRecord, error) {
	record, err := scanInnerCodeRecord(q.QueryRow(`SELECT `+innerCodeListColumns+
		` FROM syb_inner_code_records WHERE id=?`, id))
	if errors.Is(err, sql.ErrNoRows) {
		return nil, nil
	}
	if err != nil {
		return nil, err
	}
	return &record, nil
}

// SaveInnerCodeRecheck 保存只读重新核对的远端结果，不执行状态领取或写入。
func SaveInnerCodeRecheck(q Execer, id int64, status model.InnerCodeStatus, message, remoteCode, checkedAt string) error {
	result, err := q.Exec(`UPDATE syb_inner_code_records
		SET status=?,result_message=?,remote_inner_code=?,
		    applied_at=CASE WHEN ?='updated' THEN ? ELSE applied_at END,updated_at=?
		WHERE id=? AND status='needs_check'`, status, message, nullableString(remoteCode), status, checkedAt, checkedAt, id)
	if err != nil {
		return fmt.Errorf("保存档口入库码核对结果失败: %w", err)
	}
	if affected, err := result.RowsAffected(); err != nil || affected != 1 {
		return fmt.Errorf("档口入库码记录 %d 已不需要核对", id)
	}
	return nil
}

// InterruptApplyingInnerCodes 在启动时把未知结果的 applying 收敛为 needs_check。
func InterruptApplyingInnerCodes(q Execer, interruptedAt string) (int, error) {
	result, err := q.Exec(`UPDATE syb_inner_code_records
		SET status='needs_check',result_message='Admin 在回写完成前退出，请重新核对远端结果；系统不会自动重写',
		    updated_at=? WHERE status='applying'`, interruptedAt)
	if err != nil {
		return 0, fmt.Errorf("恢复中断的档口入库码回写失败: %w", err)
	}
	affected, err := result.RowsAffected()
	if err != nil {
		return 0, fmt.Errorf("读取中断档口入库码数量失败: %w", err)
	}
	return int(affected), nil
}

func nullablePositiveInt(value int) any {
	if value <= 0 {
		return nil
	}
	return value
}

func nullablePositiveInt64(value int64) any {
	if value <= 0 {
		return nil
	}
	return value
}

func nullableString(value string) any {
	if value == "" {
		return nil
	}
	return value
}