package server

import (
	"encoding/json"
	"net/http"
	"regexp"
	"strings"

	agentcommand "git-ssh.u1680832.nyat.app/weichen/Agent-Command.git"
	"git-ssh.u1680832.nyat.app/weichen/Agent-System-Backend.git/internal/store"
	core "git-ssh.u1680832.nyat.app/weichen/Agent-System-Core.git"
)

var userCommandSlug = regexp.MustCompile(`^[a-z][a-z0-9-]*$`)

func (s *Server) listSecrets(w http.ResponseWriter, r *http.Request) {
	list, err := s.st.ListSecrets(s.owner(r))
	writeJSONOr(w, list, err)
}

func (s *Server) createSecret(w http.ResponseWriter, r *http.Request) {
	var req struct {
		Service string `json:"service"`
		Label   string `json:"label"`
		Value   string `json:"value"`
	}
	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
		http.Error(w, err.Error(), http.StatusBadRequest)
		return
	}
	sec, err := s.st.AddSecret(s.owner(r), req.Service, req.Label, req.Value)
	if err != nil {
		http.Error(w, err.Error(), http.StatusBadRequest)
		return
	}
	writeJSON(w, http.StatusOK, sec)
}

func (s *Server) activateSecret(w http.ResponseWriter, r *http.Request) {
	writeOKOr(w, s.st.ActivateSecret(s.owner(r), r.PathValue("id")))
}

func (s *Server) renameSecret(w http.ResponseWriter, r *http.Request) {
	var req struct {
		Label string `json:"label"`
	}
	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
		http.Error(w, err.Error(), http.StatusBadRequest)
		return
	}
	writeOKOr(w, s.st.RenameSecret(s.owner(r), r.PathValue("id"), req.Label))
}

func (s *Server) deleteSecret(w http.ResponseWriter, r *http.Request) {
	writeOKOr(w, s.st.DeleteSecret(s.owner(r), r.PathValue("id")))
}

func (s *Server) listContextEntries(w http.ResponseWriter, r *http.Request) {
	q := r.URL.Query()
	list, err := s.st.ListContextEntries(s.owner(r), q.Get("projectId"), q.Get("conversationId"))
	writeJSONOr(w, list, err)
}

func (s *Server) saveContextEntry(w http.ResponseWriter, r *http.Request) {
	var e store.ContextEntry
	if err := json.NewDecoder(r.Body).Decode(&e); err != nil {
		http.Error(w, err.Error(), http.StatusBadRequest)
		return
	}
	saved, err := s.st.SaveContextEntry(s.owner(r), e)
	if err != nil {
		http.Error(w, err.Error(), http.StatusBadRequest)
		return
	}
	writeJSON(w, http.StatusOK, saved)
}

func (s *Server) deleteContextEntry(w http.ResponseWriter, r *http.Request) {
	writeOKOr(w, s.st.DeleteContextEntry(s.owner(r), r.PathValue("id")))
}

func (s *Server) listUserPromptCommands(w http.ResponseWriter, r *http.Request) {
	list, err := s.st.ListUserCommands(s.owner(r))
	writeJSONOr(w, list, err)
}

func (s *Server) saveUserPromptCommand(w http.ResponseWriter, r *http.Request) {
	var c store.UserCommand
	if err := json.NewDecoder(r.Body).Decode(&c); err != nil {
		http.Error(w, err.Error(), http.StatusBadRequest)
		return
	}
	saved, err := s.st.SaveUserCommand(s.owner(r), c)
	if err != nil {
		http.Error(w, err.Error(), http.StatusBadRequest)
		return
	}
	s.registerUserPrompt(saved)
	writeJSON(w, http.StatusOK, saved)
}

func (s *Server) deleteUserPromptCommand(w http.ResponseWriter, r *http.Request) {
	owner := s.owner(r)
	id := r.PathValue("id")
	list, _ := s.st.ListUserCommands(owner)
	var name string
	for _, c := range list {
		if c.ID == id {
			name = c.Name
		}
	}
	if err := s.st.DeleteUserCommand(owner, id); err != nil {
		writeStoreErr(w, err)
		return
	}
	if s.Bus != nil && name != "" {
		s.Bus.UnregisterUser(userCommandID(name), name)
	}
	writeJSON(w, http.StatusOK, map[string]any{"deleted": id})
}

func (s *Server) excludeMessage(w http.ResponseWriter, r *http.Request) {
	var req struct {
		Excluded *bool `json:"excluded"`
	}
	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
		http.Error(w, err.Error(), http.StatusBadRequest)
		return
	}
	excluded := true
	if req.Excluded != nil {
		excluded = *req.Excluded
	}
	msg, err := s.st.MessageByID(r.PathValue("id"))
	if err != nil {
		writeStoreErr(w, err)
		return
	}
	if _, err := s.st.GetConversation(s.owner(r), msg.ConversationID); err != nil {
		writeStoreErr(w, err)
		return
	}
	writeOKOr(w, s.st.ExcludeRunGroup(msg.ID, excluded))
}

func (s *Server) selectVariant(w http.ResponseWriter, r *http.Request) {
	msg, err := s.st.MessageByID(r.PathValue("id"))
	if err != nil {
		writeStoreErr(w, err)
		return
	}
	if _, err := s.st.GetConversation(s.owner(r), msg.ConversationID); err != nil {
		writeStoreErr(w, err)
		return
	}
	writeOKOr(w, s.st.SelectVariant(msg.ID))
}

func (s *Server) regenerateMessage(w http.ResponseWriter, r *http.Request) {
	owner := s.owner(r)
	convID := r.PathValue("id")
	conv, err := s.st.GetConversation(owner, convID)
	if err != nil {
		writeStoreErr(w, err)
		return
	}
	if err := s.projectWork(r.Context(), owner, conv.ProjectID); err != nil {
		writeProjectErr(w, err)
		return
	}
	var req struct {
		MessageID string `json:"messageId"`
	}
	if err := json.NewDecoder(r.Body).Decode(&req); err != nil || req.MessageID == "" {
		http.Error(w, "messageId required", http.StatusBadRequest)
		return
	}
	target, err := s.st.MessageByID(req.MessageID)
	if err != nil || target.ConversationID != convID || target.Role != core.RoleAssistant {
		http.Error(w, "assistant message required", http.StatusBadRequest)
		return
	}
	hist, err := s.st.ListMessages(convID)
	if err != nil {
		writeStoreErr(w, err)
		return
	}
	var user core.Message
	found := false
	maxIndex := target.VariantIndex
	for _, m := range hist {
		if m.VariantGroup != "" && m.VariantGroup == target.VariantGroup && m.VariantIndex > maxIndex {
			maxIndex = m.VariantIndex
		}
		if m.ID == target.ID {
			found = true
		}
		if !found && m.Role == core.RoleUser {
			user = m
		}
	}
	if user.ID == "" {
		http.Error(w, "no user turn to regenerate", http.StatusBadRequest)
		return
	}
	group := target.VariantGroup
	if group == "" {
		group = "var_" + target.ID
	}
	if err := s.st.SetMessageFlags(target.ID, true, group, target.VariantIndex); err != nil {
		writeStoreErr(w, err)
		return
	}
	if err := s.st.ExcludeRunGroup(target.ID, true); err != nil {
		writeStoreErr(w, err)
		return
	}
	if err := s.st.SetRegenPending(convID, group, maxIndex+1); err != nil {
		writeStoreErr(w, err)
		return
	}
	if _, err := s.mgr.RewindFiles(owner, convID, user.ID); err != nil {
		// 没有文件检查点时仍然重新生成回复。
	}
	run, err := s.mgr.StartConversationRun(conv, user, nil, nil)
	if err != nil {
		_, _, _ = s.st.TakeRegenPending(convID)
		writeStoreErr(w, err)
		return
	}
	writeJSON(w, http.StatusOK, map[string]any{"run": run, "variantGroup": group})
}

func (s *Server) expandUserCommand(owner, text string) (string, bool) {
	fields := strings.Fields(text)
	if len(fields) == 0 || !strings.HasPrefix(fields[0], "/") {
		return "", false
	}
	list, err := s.st.ListUserCommands(owner)
	if err != nil {
		return "", false
	}
	name := strings.ToLower(fields[0])
	rest := strings.TrimSpace(strings.TrimPrefix(text, fields[0]))
	for _, c := range list {
		if strings.ToLower(c.Name) != name {
			continue
		}
		body := c.Template
		if strings.Contains(body, "{{input}}") {
			body = strings.ReplaceAll(body, "{{input}}", rest)
		} else if rest != "" {
			body = strings.TrimSpace(body + "\n" + rest)
		}
		return body, true
	}
	return "", false
}

func userCommandID(name string) string {
	slug := strings.TrimPrefix(strings.ToLower(name), "/")
	return "user." + slug
}

func (s *Server) registerUserPrompt(c store.UserCommand) {
	if s.Bus == nil {
		return
	}
	slug := strings.TrimPrefix(strings.ToLower(c.Name), "/")
	if !userCommandSlug.MatchString(slug) {
		return
	}
	_ = s.Bus.RegisterUser(agentcommand.CommandSpec{
		ID: userCommandID(c.Name), Title: c.Title, Description: "展开为提示词，不自动执行",
	}, c.Name)
}

func (s *Server) appendUserPromptCommands(owner string, out []map[string]any) []map[string]any {
	list, err := s.st.ListUserCommands(owner)
	if err != nil {
		return out
	}
	for _, c := range list {
		s.registerUserPrompt(c)
		out = append(out, map[string]any{
			"id": userCommandID(c.Name), "name": c.Name, "title": c.Title,
			"description": "展开为提示词", "source": "user", "enabled": true,
		})
	}
	return out
}