package service

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

	"cmautobuy/admin/model"
	"cmautobuy/admin/repository"
)

// InnerCodeStatusOption 是页面状态筛选项。
type InnerCodeStatusOption struct {
	Value string
	Text  string
}

var innerCodeStatusOptions = []InnerCodeStatusOption{
	{"", "全部状态"},
	{string(model.InnerCodePending), "待匹配"},
	{string(model.InnerCodeReady), "可回写"},
	{string(model.InnerCodeQueued), "排队中"},
	{string(model.InnerCodeApplying), "回写中"},
	{string(model.InnerCodeUpdated), "已回写"},
	{string(model.InnerCodeAlreadyFilled), "已存在"},
	{string(model.InnerCodeSkipped), "已跳过"},
	{string(model.InnerCodeFailed), "失败"},
	{string(model.InnerCodeNeedsCheck), "需核对"},
}

// 删除只改本地数据库，可覆盖最大单页。回写已改为后台队列，不再限制选择 20 条。
const InnerCodeDeleteBatchLimit = 100

// InnerCodeRowView 是正式页面的一行。
type InnerCodeRowView struct {
	ID               int64
	BusinessDate     string
	OrderNumber      string
	Stall            string
	SpecRaw          string
	SybSpec          string
	InnerCode        string
	RemoteInnerCode  string
	Status           string
	StatusText       string
	StatusClass      string
	ResultMessage    string
	UpdatedAt        string
	CanMatch         bool
	CanApply         bool
	HasRemoteOldCode bool
	CanRecheck       bool
}

// InnerCodeListPage 是列表、分页和底栏统计。
type InnerCodeListPage struct {
	Rows       []InnerCodeRowView
	Total      int
	Page       int
	TotalPages int
	Status     string
	Keyword    string
	Date       string
	Counts     repository.InnerCodeStatusCounts
	IsFiltered bool
}

// InnerCodeStatusOptions 返回稳定顺序的筛选项副本。
func InnerCodeStatusOptions() []InnerCodeStatusOption {
	return append([]InnerCodeStatusOption(nil), innerCodeStatusOptions...)
}

// ListInnerCodePage 使用默认页容量返回档口入库码列表。
func ListInnerCodePage(db *sql.DB, businessDate, status, keyword string, requestedPage int) (*InnerCodeListPage, error) {
	return ListInnerCodePageWithPageSize(db, businessDate, status, keyword, requestedPage, DefaultPageSize)
}

// ListInnerCodePageWithPageSize 校验筛选并按白名单页容量执行 SQL 分页。
func ListInnerCodePageWithPageSize(db *sql.DB, businessDate, status, keyword string, requestedPage, pageSize int) (*InnerCodeListPage, error) {
	pageSize = NormalizePageSize(pageSize)
	status = strings.TrimSpace(status)
	if !validInnerCodeStatusFilter(status) {
		status = ""
	}
	keyword = strings.TrimSpace(keyword)
	filter := repository.InnerCodeListFilter{BusinessDate: businessDate, Status: status, Keyword: keyword}
	total, err := repository.CountInnerCodeRecords(db, filter)
	if err != nil {
		return nil, err
	}
	totalPages := TotalPages(total, pageSize)
	page := ClampPage(requestedPage, totalPages)
	records, err := repository.ListInnerCodeRecords(db, filter, pageSize, (page-1)*pageSize)
	if err != nil {
		return nil, err
	}
	counts, err := repository.CountInnerCodeStatuses(db, businessDate)
	if err != nil {
		return nil, err
	}
	result := &InnerCodeListPage{Total: total, Page: page, TotalPages: totalPages,
		Status: status, Keyword: keyword, Date: businessDate, Counts: counts,
		IsFiltered: status != "" || keyword != ""}
	result.Rows = make([]InnerCodeRowView, 0, len(records))
	for _, record := range records {
		result.Rows = append(result.Rows, innerCodeRowView(record))
	}
	return result, nil
}

func validInnerCodeStatusFilter(status string) bool {
	for _, option := range innerCodeStatusOptions {
		if option.Value == status {
			return true
		}
	}
	return false
}

func innerCodeRowView(record model.InnerCodeRecord) InnerCodeRowView {
	statusText := map[model.InnerCodeStatus]string{
		model.InnerCodePending: "待匹配", model.InnerCodeReady: "可回写",
		model.InnerCodeQueued:   "排队中",
		model.InnerCodeApplying: "回写中", model.InnerCodeUpdated: "已回写",
		model.InnerCodeAlreadyFilled: "已存在", model.InnerCodeSkipped: "已跳过",
		model.InnerCodeFailed: "失败", model.InnerCodeNeedsCheck: "需核对",
	}[record.Status]
	if statusText == "" {
		statusText = "未知"
	}
	canMatch := record.Status == model.InnerCodePending ||
		record.Status == model.InnerCodeReady ||
		record.Status == model.InnerCodeSkipped ||
		record.Status == model.InnerCodeFailed
	canApply := record.Status == model.InnerCodeReady
	return InnerCodeRowView{
		ID: record.ID, BusinessDate: record.BusinessDate, OrderNumber: record.OrderNumber,
		Stall: displayInnerCodeValue(record.Stall), SpecRaw: displayInnerCodeValue(record.SpecRaw),
		SybSpec: displayInnerCodeValue(record.SybSpec), InnerCode: record.InnerCode,
		RemoteInnerCode: displayInnerCodeValue(record.RemoteInnerCode), Status: string(record.Status),
		StatusText: statusText, StatusClass: "inner-code-status-" + string(record.Status),
		ResultMessage: displayInnerCodeValue(record.ResultMessage), UpdatedAt: formatLocalTime(record.UpdatedAt),
		CanMatch:         canMatch,
		CanApply:         canApply,
		HasRemoteOldCode: canApply && record.RemoteInnerCode != "",
		CanRecheck:       record.Status == model.InnerCodeNeedsCheck,
	}
}

func displayInnerCodeValue(value string) string {
	if strings.TrimSpace(value) == "" {
		return "—"
	}
	return value
}

// InnerCodeStatusMessage 生成底栏可读统计。
func InnerCodeStatusMessage(page *InnerCodeListPage) string {
	return fmt.Sprintf("共 %d 条，可回写 %d 条，排队中 %d 条，回写中 %d 条，需核对 %d 条；当前筛选 %d 条",
		page.Counts.Total, page.Counts.Ready, page.Counts.Queued, page.Counts.Applying,
		page.Counts.NeedsCheck, page.Total)
}