MailUI4Agents/gateway/internal/handler/me.go

package handler

import (
	"errors"
	"net/http"
	"time"

	"github.com/agentmail/gateway/internal/middleware"
	"github.com/agentmail/gateway/internal/models"
	"github.com/agentmail/gateway/internal/repo"
	"github.com/google/uuid"
)

// ---------- /me：当前登录人类用户的邮箱（全部路由需 UserAuth） ----------

type meSendMailRequest struct {
	To      string `json:"to"`      // name@path.session
	CC      string `json:"cc"`      // 多个 name@path.session
	Subject string `json:"subject"`
	Body    string `json:"body"`
	ReplyTo string `json:"reply_to"`
	// SessionAlias 仅在本次投递【新建】会话时生效，为新会话命名
	SessionAlias string `json:"session_alias"`
	// AttachmentIDs 先用 POST /me/attachments 上传拿到的 id
	AttachmentIDs []string `json:"attachment_ids"`
	// MaxRounds 是本次任务的往返预算（0/省略 = 不限）。
	//
	// 配额的真实语义是「这件事值得多少个来回」——那是任务的属性，
	// 所以在派活的这一刻给，而不是事后到管理员页面去调某个 Agent 的全局配额。
	// 仅在本次投递【新建】会话时生效；续谈已有会话请用
	// PUT /sessions/{id}/budget（对话页里可随时改）。
	MaxRounds *int `json:"max_rounds"`
}

// POST /api/v1/me/mail/send
func MeSendMail(w http.ResponseWriter, r *http.Request) {
	user := middleware.GetUser(r)
	if user == nil {
		Error(w, http.StatusUnauthorized, "not authenticated")
		return
	}

	var req meSendMailRequest
	if !DecodeBody(w, r, &req) {
		return
	}
	if req.To == "" || req.Subject == "" || req.Body == "" {
		Error(w, http.StatusBadRequest, "Missing to, subject, or body")
		return
	}

	to, err := models.ParseAddress(req.To)
	if err != nil {
		Error(w, http.StatusBadRequest, "Invalid to address: "+err.Error())
		return
	}
	ccList, err := models.ParseAddressList(req.CC)
	if err != nil {
		Error(w, http.StatusBadRequest, "Invalid cc address: "+err.Error())
		return
	}
	attachIDs, err := parseAttachmentIDs(req.AttachmentIDs)
	if err != nil {
		Error(w, http.StatusBadRequest, err.Error())
		return
	}

	// human@ 是兼容别名，人类发信时解析为自己
	to = resolveHumanAlias(to, user.Username)
	for i := range ccList {
		ccList[i] = resolveHumanAlias(ccList[i], user.Username)
	}

	// 权限边界：校验可调用的 Agent 与可访问的目录
	if msg := checkScope(r, user, append([]models.Address{to}, ccList...)); msg != "" {
		Error(w, http.StatusForbidden, msg)
		return
	}

	// 可达性：收件人必须存在且未停用，否则邮件进黑洞
	if !checkDeliverable(w, r, append([]models.Address{to}, ccList...)) {
		return
	}

	sessionID, parentMailID, err := resolveTarget(r, to, req.ReplyTo, user.Username, req.Subject, req.SessionAlias, "")
	if err != nil {
		writeErr(w, err, "Failed to resolve session")
		return
	}
	// 人类发起的会话归属于该用户
	_ = repo.SetSessionOwner(r.Context(), sessionID, user.ID)

	// 新建会话时定往返预算。只在新建时设：续谈已有会话若也接受这个字段，
	// 每封新信都会悄悄改掉对方正在遵守的预算，人却不一定意识到自己改了。
	//
	// 没显式给就用【收件 Agent 的默认值】。默认值挂在 Agent 上而不是全站一个数：
	// 跑测试的小工具与重构整个模块的 Agent，合理来回数差一个量级。
	if parentMailID == nil {
		rounds := 0
		if req.MaxRounds != nil {
			if *req.MaxRounds < 0 {
				Error(w, http.StatusBadRequest, "max_rounds 不能为负")
				return
			}
			rounds = *req.MaxRounds
		} else {
			rounds = repo.DefaultRoundsFor(r.Context(), to.Name)
		}
		if _, err := repo.SetSessionBudget(r.Context(), sessionID, rounds); err != nil {
			Error(w, http.StatusInternalServerError, "Failed to set session budget")
			return
		}
	}

	// 人类侧不产生改名提议（人直接有改名按钮，用不着向自己提议），
	// 但仍然剥掉标记：粘贴进正文时它会被渲染成一行可见的转义文本。
	_, body := extractRenameProposal(req.Body)

	mailID, err := repo.CreateMail(r.Context(), sessionID, parentMailID,
		user.Username, "", to.Name, to.Path, req.Subject, body, ccList)
	if err != nil {
		Error(w, http.StatusInternalServerError, "Failed to create mail")
		return
	}

	if !attachAll(w, r, mailID, attachIDs, user.Username) {
		return
	}

	notifyRecipients(r.Context(), to, ccList, sessionID, mailID, user.Username, req.Subject, parentIDString(parentMailID))

	resp := map[string]any{
		"mail_id":       mailID.String(),
		"session_id":    sessionID.String(),
		"session_alias": repo.SessionAliasOf(r.Context(), sessionID),
	}
	// 回传预算，让前端不必再单独查一次就能显示「本任务还剩几个来回」
	if b, err := repo.GetSessionBudget(r.Context(), sessionID); err == nil && !b.Unlimited {
		resp["budget_max"] = b.Max
		resp["budget_used"] = b.Used
		resp["budget_remaining"] = b.Remaining
	}
	JSON(w, http.StatusOK, resp)
}

// GET /api/v1/me/mail/inbox
func MeGetInbox(w http.ResponseWriter, r *http.Request) {
	user := middleware.GetUser(r)
	if user == nil {
		Error(w, http.StatusUnauthorized, "not authenticated")
		return
	}

	status := r.URL.Query().Get("status")
	if status == "" {
		status = "all"
	}
	limit := 50
	if l := r.URL.Query().Get("limit"); l != "" {
		if n, err := parseInt(l); err == nil && n > 0 {
			limit = n
		}
	}

	mails, err := repo.ListInbox(r.Context(), user.Username, status, limit)
	if err != nil {
		Error(w, http.StatusInternalServerError, "Failed to list inbox")
		return
	}
	// 列表页要显示附件图标与下载入口
	ptrs := make([]*models.Mail, len(mails))
	for i := range mails {
		ptrs[i] = &mails[i]
	}
	fillAttachments(r, ptrs...)
	total, _ := repo.CountUnread(r.Context(), user.Username)

	JSON(w, http.StatusOK, map[string]interface{}{
		"mails": emptySlice(mails),
		"total": total,
	})
}

// GET /api/v1/me/mail/sent
func MeGetSent(w http.ResponseWriter, r *http.Request) {
	user := middleware.GetUser(r)
	if user == nil {
		Error(w, http.StatusUnauthorized, "not authenticated")
		return
	}

	limit := 50
	if l := r.URL.Query().Get("limit"); l != "" {
		if n, err := parseInt(l); err == nil && n > 0 {
			limit = n
		}
	}

	mails, err := repo.ListSentBy(r.Context(), user.Username, limit)
	if err == nil {
		ptrs := make([]*models.Mail, len(mails))
		for i := range mails {
			ptrs[i] = &mails[i]
		}
		fillAttachments(r, ptrs...)
	}
	if err != nil {
		Error(w, http.StatusInternalServerError, "Failed to list sent")
		return
	}
	JSON(w, http.StatusOK, map[string]interface{}{
		"mails": emptySlice(mails),
	})
}

// GET /api/v1/me/sessions
func MeGetSessions(w http.ResponseWriter, r *http.Request) {
	user := middleware.GetUser(r)
	if user == nil {
		Error(w, http.StatusUnauthorized, "not authenticated")
		return
	}

	scope := user.Username
	if user.IsAdmin() && r.URL.Query().Get("all") == "true" {
		scope = ""
	}

	sessions, err := repo.ListSessionsFor(r.Context(), scope, 50)
	if err != nil {
		Error(w, http.StatusInternalServerError, "Failed to list sessions")
		return
	}

	type SessionOut struct {
		SessionID    uuid.UUID `json:"session_id"`
		SessionAlias *string   `json:"session_alias"`
		FromAgent    string    `json:"from_agent"`
		Subject      string    `json:"subject"`
		Status       string    `json:"status"`
		CreatedAt    time.Time `json:"created_at"`
		UpdatedAt    time.Time `json:"updated_at"`
		MailCount    int       `json:"mail_count"`
		UnreadCount  int       `json:"unread_count"`
		// 往返预算随列表一并返回：预算是【任务】的属性，
		// 工作列表上就应当看得见哪些任务快跑满了，
		// 而不是点进去一个一个查。
		MaxRounds  int `json:"max_rounds"`
		UsedRounds int `json:"used_rounds"`
	}

	result := make([]SessionOut, 0, len(sessions))
	for _, s := range sessions {
		unread, _ := repo.CountUnreadInSession(r.Context(), user.Username, s.ID)
		result = append(result, SessionOut{
			SessionID:    s.ID,
			SessionAlias: s.Alias,
			FromAgent:    s.FromAgent,
			Subject:      s.Subject,
			Status:       s.Status,
			CreatedAt:    s.CreatedAt,
			UpdatedAt:    s.UpdatedAt,
			MailCount:    s.MailCount,
			UnreadCount:  unread,
			MaxRounds:    s.MaxRounds,
			UsedRounds:   s.UsedRounds,
		})
	}

	JSON(w, http.StatusOK, map[string]interface{}{
		"sessions": result,
	})
}

// resolveHumanAlias 把兼容别名 human 解析为具体用户名
func resolveHumanAlias(a models.Address, username string) models.Address {
	if a.Name != "human" {
		return a
	}
	a.Name = username
	a.Raw = username + "@" + a.Path
	if a.Session != "" {
		a.Raw += "." + a.Session
	}
	return a
}

// checkScope 校验用户的 Agent 白名单与目录白名单；返回空串表示通过。
// 收件方是人类用户时不受 Agent 白名单约束（人与人通信始终允许）。
func checkScope(r *http.Request, user *models.User, addrs []models.Address) string {
	if user.IsAdmin() {
		return ""
	}
	for _, a := range addrs {
		if a.Name == "" || a.Name == user.Username {
			continue
		}
		isHuman, err := repo.IsHumanUser(r.Context(), a.Name)
		if err != nil {
			return "无法校验收件人权限"
		}
		if !isHuman && !user.CanUseAgent(a.Name) {
			return "无权调用 Agent: " + a.Name
		}
		if !user.CanUsePath(a.Path) {
			return "无权访问目录: " + a.Path
		}
	}
	return ""
}

// checkDeliverable 校验每个收件人（含拄送）当前能不能收信，写好响应并返回 false 表示已拒绝。
//
// 拄送位同样要查：不查的话 cc 就成了绕过口 —— 把已删除的 Agent 放到 cc 位
// 依旧能把邮件送进黑洞，而且因为不是主收件人更不容易被发现。
func checkDeliverable(w http.ResponseWriter, r *http.Request, addrs []models.Address) bool {
	for _, a := range addrs {
		err := repo.RecipientDeliverable(r.Context(), a.Name)
		switch {
		case err == nil:
			continue
		case errors.Is(err, repo.ErrRecipientUnknown):
			Error(w, http.StatusNotFound,
				"收件人不存在："+a.Name+"。它既不是人类用户也不是已注册的 Agent（可能已被删除）。")
			return false
		case errors.Is(err, repo.ErrRecipientDisabled):
			Error(w, http.StatusConflict,
				"Agent \""+a.Name+"\" 已被管理员停用，现在不接收新任务。请先在管理页恢复它。")
			return false
		default:
			Error(w, http.StatusInternalServerError, "无法校验收件人状态")
			return false
		}
	}
	return true
}