package gateway

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

	apperr "git.yeij.top/AskaEth/Cyrene_v2/internal/errors"
	"git.yeij.top/AskaEth/Cyrene_v2/internal/runtime/knowledge"
	"git.yeij.top/AskaEth/Cyrene_v2/internal/runtime/memory"
)

// 管理侧记忆 + 知识库写端点（仅 owner，带审计）。添加记忆
// 会把真实条目写入记忆存储（owner 私有，安全），而 RAG 索引
// 把文档导入项目索引使其可被检索。二者在各自
// 后端存储未接线时都退化为明确的 501。

// memoryAddRequest 是 POST /api/v1/admin/memories 的请求体。
type memoryAddRequest struct {
	PersonaID string `json:"personaId"`
	Content   string `json:"content"`
	Scope     string `json:"scope"`
}

// adminAddMemory 为主人写入单条记忆。它是手动的
// 「添加记忆」路径：条目默认作用于 persona，因此行为与
// loop 已在写的「记住 X」路径一致。Scope 可省略（默认
// persona），或为 user|persona|project 之一；非法非空 scope 会被拒绝。
func (s *Server) adminAddMemory(w http.ResponseWriter, r *http.Request) {
	var req memoryAddRequest
	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
		writeError(w, apperr.Wrap(apperr.ErrBadRequest, "bad_request", "invalid request body"))
		return
	}
	personaID := strings.TrimSpace(req.PersonaID)
	if personaID == "" {
		personaID = "cyrene"
	}
	content := strings.TrimSpace(req.Content)
	if content == "" {
		s.auditClaims(r, "memory.add", "error")
		writeError(w, apperr.Wrap(apperr.ErrBadRequest, "bad_request", "content is required"))
		return
	}
	rawScope := strings.TrimSpace(req.Scope)
	if rawScope != "" && !isValidMemoryScope(rawScope) {
		s.auditClaims(r, "memory.add", "error")
		writeError(w, apperr.Wrap(apperr.ErrBadRequest, "bad_request", "scope must be one of user|persona|project"))
		return
	}
	store, ok := s.memories.(*memory.Store)
	if !ok {
		s.auditClaims(r, "memory.add", "error")
		writeError(w, &apperr.AppError{Code: "not_implemented", Message: "记忆存储未配置（未注入 memory.Store）", HTTPCode: http.StatusNotImplemented})
		return
	}
	stored, err := store.Add(r.Context(), memory.MemoryItem{
		PersonaID: personaID,
		Content:   content,
		Scope:     memory.Scope(rawScope),
	})
	if err != nil {
		s.auditClaims(r, "memory.add", "error")
		s.log.Error("memory add", "err", err)
		writeError(w, apperr.Wrap(apperr.ErrInternal, "memory_add_failed", "failed to add memory"))
		return
	}
	s.auditClaims(r, "memory.add", "ok")
	writeJSON(w, http.StatusCreated, map[string]any{"id": stored.ID, "scope": string(stored.Scope), "text": stored.Content})
}

// isValidMemoryScope 报告 raw 是否是已定义的记忆作用域之一。
func isValidMemoryScope(raw string) bool {
	switch memory.Scope(strings.TrimSpace(raw)) {
	case memory.ScopeUser, memory.ScopePersona, memory.ScopeProject:
		return true
	default:
		return false
	}
}

// ragIndexRequest 是 POST /api/v1/admin/rag 的请求体。
type ragIndexRequest struct {
	Name    string `json:"name"`
	Desc    string `json:"desc"`
	Content string `json:"content"`
}

// adminIndexRag 导入一份知识文档：它把 name/description 与
// content 交给知识存储，后者切分它并索引进项目
// 索引，使文档可被关键词检索。它是管理侧的「导入文档」路径。
func (s *Server) adminIndexRag(w http.ResponseWriter, r *http.Request) {
	var req ragIndexRequest
	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
		writeError(w, apperr.Wrap(apperr.ErrBadRequest, "bad_request", "invalid request body"))
		return
	}
	name := strings.TrimSpace(req.Name)
	if name == "" {
		s.auditClaims(r, "rag.index", "error")
		writeError(w, apperr.Wrap(apperr.ErrBadRequest, "bad_request", "name is required"))
		return
	}
	content := strings.TrimSpace(req.Content)
	if content == "" {
		s.auditClaims(r, "rag.index", "error")
		writeError(w, apperr.Wrap(apperr.ErrBadRequest, "bad_request", "content is required"))
		return
	}
	if s.rag == nil {
		s.auditClaims(r, "rag.index", "error")
		writeError(w, &apperr.AppError{Code: "not_implemented", Message: "知识库 RAG 服务未配置（未注入 RagStore）", HTTPCode: http.StatusNotImplemented})
		return
	}
	if err := s.rag.IndexDocument(r.Context(), knowledge.Doc{
		Name:    name,
		Desc:    strings.TrimSpace(req.Desc),
		Content: content,
	}); err != nil {
		s.auditClaims(r, "rag.index", "error")
		s.log.Error("rag index", "err", err)
		writeError(w, apperr.Wrap(apperr.ErrInternal, "rag_index_failed", "failed to index document"))
		return
	}
	s.auditClaims(r, "rag.index", "ok")
	writeJSON(w, http.StatusCreated, map[string]any{"name": name})
}

// ragDeleteRequest 是 POST /api/v1/admin/rag/delete 的请求体。
type ragDeleteRequest struct {
	ID string `json:"id"`
}

// adminDeleteRag 按 id 移除一份知识文档：存储删除
// 项目索引条目并级联其章节。文档缺失时返回 404，
// 存储无法删除时返回明确的 501，其他失败
// 返回 500 —— 绝不编造成功。该路由受 owner 门控且带审计。
func (s *Server) adminDeleteRag(w http.ResponseWriter, r *http.Request) {
	if s.rag == nil {
		s.auditClaims(r, "rag.delete", "error")
		writeError(w, &apperr.AppError{Code: "not_implemented", Message: "知识库 RAG 服务未配置（未注入 RagStore）", HTTPCode: http.StatusNotImplemented})
		return
	}
	var req ragDeleteRequest
	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
		writeError(w, apperr.Wrap(apperr.ErrBadRequest, "bad_request", "invalid request body"))
		return
	}
	id := strings.TrimSpace(req.ID)
	if id == "" {
		writeError(w, apperr.Wrap(apperr.ErrBadRequest, "bad_request", "id is required"))
		return
	}
	if err := s.rag.DeleteDocument(r.Context(), id); err != nil {
		s.auditClaims(r, "rag.delete", "error")
		switch {
		case errors.Is(err, knowledge.ErrDocumentNotFound):
			writeError(w, apperr.Wrap(apperr.ErrNotFound, "not_found", "知识库文档 %q 不存在", id))
		case errors.Is(err, knowledge.ErrWriteUnsupported):
			writeError(w, &apperr.AppError{Code: "not_implemented", Message: "该知识库存储不支持删除", HTTPCode: http.StatusNotImplemented})
		default:
			s.log.Error("rag delete", "id", id, "err", err)
			writeError(w, apperr.Wrap(apperr.ErrInternal, "rag_delete_failed", "failed to delete knowledge document"))
		}
		return
	}
	s.auditClaims(r, "rag.delete", "ok")
	writeJSON(w, http.StatusOK, map[string]any{"id": id, "deleted": true})
}