package handler

import (
	"regexp"
	"strings"
	"unicode/utf8"

	"kefu-cloud/server/internal/model"
	"kefu-cloud/server/internal/ws"
)

var (
	reMobileCN = regexp.MustCompile(`(?i)(?:手机|电话|联系|号|tel|phone|mobile)?[：:\s]*((?:\+?86[-\s]?)?1[3-9]\d{9})`)
	reMobileStrict = regexp.MustCompile(`(?:^|[^\d])(1[3-9]\d{9})(?:[^\d]|$)`)
	reEmail    = regexp.MustCompile(`(?i)[a-z0-9._%+\-]+@[a-z0-9.\-]+\.[a-z]{2,}`)
	// 允许「微信是 xxx / 微信：xxx / 微信号 xxx」等口语写法
	reWechat   = regexp.MustCompile(`(?i)(?:微信|微信号|vx|v信|wx)[号]?(?:是|为|：|:|[\s　]+)[\s　]*([a-zA-Z][-_a-zA-Z0-9]{5,19})`)
	reWechatID = regexp.MustCompile(`(?i)\b(wxid_[a-zA-Z0-9]{5,20})\b`)
	reQQ       = regexp.MustCompile(`(?i)(?:QQ|扣扣)[号]?(?:是|为|：|:|[\s　]+)[\s　]*([1-9]\d{4,11})`)
)

type extractedContact struct {
	Kind  string
	Value string
}

// extractContactsFromText 从文本中提取联系方式（手机/微信/邮箱/QQ）。
func extractContactsFromText(text string) []extractedContact {
	text = strings.TrimSpace(text)
	if text == "" {
		return nil
	}
	// 限制扫描长度
	if utf8.RuneCountInString(text) > 2000 {
		text = string([]rune(text)[:2000])
	}

	seen := map[string]bool{}
	var out []extractedContact
	add := func(kind, val string) {
		val = strings.TrimSpace(val)
		if val == "" {
			return
		}
		// 规范化手机号
		if kind == "phone" {
			val = regexp.MustCompile(`[^\d]`).ReplaceAllString(val, "")
			if strings.HasPrefix(val, "86") && len(val) == 13 {
				val = val[2:]
			}
			if len(val) != 11 || val[0] != '1' {
				return
			}
		}
		key := kind + ":" + strings.ToLower(val)
		if seen[key] {
			return
		}
		seen[key] = true
		out = append(out, extractedContact{Kind: kind, Value: val})
	}

	for _, m := range reMobileCN.FindAllStringSubmatch(text, -1) {
		if len(m) > 1 {
			add("phone", m[1])
		}
	}
	for _, m := range reMobileStrict.FindAllStringSubmatch(text, -1) {
		if len(m) > 1 {
			add("phone", m[1])
		}
	}
	for _, m := range reEmail.FindAllString(text, -1) {
		add("email", strings.ToLower(m))
	}
	for _, m := range reWechat.FindAllStringSubmatch(text, -1) {
		if len(m) > 1 {
			add("wechat", m[1])
		}
	}
	for _, m := range reWechatID.FindAllStringSubmatch(text, -1) {
		if len(m) > 1 {
			add("wechat", m[1])
		}
	}
	for _, m := range reQQ.FindAllStringSubmatch(text, -1) {
		if len(m) > 1 {
			add("qq", m[1])
		}
	}
	return out
}

// mergeCustomerContacts 将提取结果写入客户联系方式表（已存在则跳过，不覆盖）。
// 同时：若 customers.phone/email 为空，用第一条补全（兼容旧列表搜索）。
// 返回新插入的条数。
func mergeCustomerContacts(tenantID, customerID uint, contacts []extractedContact, source string) (int, []model.CustomerContact) {
	if customerID == 0 || len(contacts) == 0 {
		return 0, nil
	}
	var customer model.Customer
	if err := model.DB.Where("id = ? AND tenant_id = ?", customerID, tenantID).First(&customer).Error; err != nil {
		return 0, nil
	}

	added := 0
	var inserted []model.CustomerContact
	updates := map[string]interface{}{}

	for _, c := range contacts {
		var exists int64
		model.DB.Model(&model.CustomerContact{}).
			Where("customer_id = ? AND kind = ? AND value = ?", customerID, c.Kind, c.Value).
			Count(&exists)
		if exists > 0 {
			continue
		}
		row := model.CustomerContact{
			TenantID:   tenantID,
			CustomerID: customerID,
			Kind:       c.Kind,
			Value:      c.Value,
			Source:     source,
		}
		if err := model.DB.Create(&row).Error; err != nil {
			continue
		}
		added++
		inserted = append(inserted, row)

		// 主字段仅在为空时填充，绝不覆盖已有值
		if c.Kind == "phone" && strings.TrimSpace(customer.Phone) == "" && updates["phone"] == nil {
			updates["phone"] = c.Value
			customer.Phone = c.Value
		}
		if c.Kind == "email" && strings.TrimSpace(customer.Email) == "" && updates["email"] == nil {
			updates["email"] = c.Value
			customer.Email = c.Value
		}
	}
	if len(updates) > 0 {
		model.DB.Model(&model.Customer{}).Where("id = ?", customerID).Updates(updates)
	}
	return added, inserted
}

func listCustomerContacts(customerID uint) []model.CustomerContact {
	var list []model.CustomerContact
	model.DB.Where("customer_id = ?", customerID).Order("id asc").Find(&list)
	return list
}

// onVisitorDraftContacts 草稿文本提取联系方式并通知坐席刷新客户资料。
func onVisitorDraftContacts(tenantID, customerID, sessionID uint, text string) {
	contacts := extractContactsFromText(text)
	if len(contacts) == 0 {
		return
	}
	n, inserted := mergeCustomerContacts(tenantID, customerID, contacts, "draft")
	if n == 0 {
		return
	}
	// 推送客户资料更新（含全部联系方式）
	var customer model.Customer
	if err := model.DB.First(&customer, customerID).Error; err != nil {
		return
	}
	all := listCustomerContacts(customerID)
	payload, err := ws.NewEvent("customer_updated", sessionID, map[string]interface{}{
		"customer":       customer,
		"contacts":       all,
		"added_contacts": inserted,
	})
	if err == nil {
		ws.DefaultHub.BroadcastToTenantStaff(tenantID, payload)
	}
}