// Passkey 的管理端点：列出、注册（两步）、删除。
//
// 全部在 guard 之后 —— 注册凭据等于发放永久登录方式，必须已是管理员。
// 删光 passkey 也不会把自已锁死：站主密码走环境变量，不在这张表里。
package admin

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

	"oneblog/internal/auth"
	"oneblog/internal/httpx"
	"oneblog/internal/store"
)

// passkeyName 是站主给这把凭据起的名字（「MacBook 指纹」「iPhone」）。
type passkeyNameRequest struct {
	Name string `json:"name"`
}

func (a *API) listPasskeys(w http.ResponseWriter, r *http.Request) {
	if r.Method != http.MethodGet {
		httpx.Error(w, http.StatusMethodNotAllowed, "GET required")
		return
	}
	owner, err := a.Store.EnsureOwner(a.cfg().AdminUser)
	if err != nil {
		httpx.ServerError(w, err)
		return
	}
	list, err := a.Store.ListPasskeys(owner.ID)
	if err != nil {
		httpx.ServerError(w, err)
		return
	}
	httpx.OK(w, map[string]any{"passkeys": list})
}

func (a *API) beginPasskey(w http.ResponseWriter, r *http.Request) {
	if a.Passkeys == nil {
		httpx.Error(w, http.StatusServiceUnavailable, "passkey 未启用")
		return
	}
	owner, err := a.Store.EnsureOwner(a.cfg().AdminUser)
	if err != nil {
		httpx.ServerError(w, err)
		return
	}
	existing, err := a.Store.ListPasskeys(owner.ID)
	if err != nil {
		httpx.ServerError(w, err)
		return
	}
	creation, token, err := a.Passkeys.BeginRegistration(owner.ID, owner.Handle, owner.Name, existing)
	if err != nil {
		httpx.ServerError(w, err)
		return
	}
	httpx.OK(w, map[string]any{"options": creation, "token": token})
}

func (a *API) finishPasskey(w http.ResponseWriter, r *http.Request) {
	if a.Passkeys == nil {
		httpx.Error(w, http.StatusServiceUnavailable, "passkey 未启用")
		return
	}
	var in struct {
		Token      string          `json:"token"`
		Name       string          `json:"name"`
		Credential json.RawMessage `json:"credential"`
	}
	if err := httpx.Decode(r, &in); err != nil || in.Token == "" || len(in.Credential) == 0 {
		httpx.BadRequest(w, "token 与 credential 都要传")
		return
	}
	name := strings.TrimSpace(in.Name)
	if len([]rune(name)) > 40 {
		httpx.BadRequest(w, "名称最多 40 字")
		return
	}
	if name == "" {
		name = "未命名设备"
	}
	owner, err := a.Store.EnsureOwner(a.cfg().AdminUser)
	if err != nil {
		httpx.ServerError(w, err)
		return
	}
	existing, err := a.Store.ListPasskeys(owner.ID)
	if err != nil {
		httpx.ServerError(w, err)
		return
	}
	pk, err := a.Passkeys.FinishRegistration(in.Token, owner.ID, owner.Handle, owner.Name, existing, in.Credential)
	if errors.Is(err, auth.ErrSessionExpired) {
		httpx.Error(w, http.StatusGone, "注册已过期，请重新开始")
		return
	}
	if err != nil {
		httpx.Error(w, http.StatusBadRequest, "passkey 校验失败："+err.Error())
		return
	}
	pk.Name = name
	created, err := a.Store.AddPasskey(pk)
	if err != nil {
		httpx.ServerError(w, err)
		return
	}
	// 公钥不回传：前端不需要，少一处能误用的字段
	created.PublicKey = ""
	httpx.Created(w, created)
}

func (a *API) deletePasskey(w http.ResponseWriter, r *http.Request) {
	if r.Method != http.MethodDelete {
		httpx.Error(w, http.StatusMethodNotAllowed, "DELETE required")
		return
	}
	id, err := strconv.ParseInt(strings.Trim(strings.TrimPrefix(r.URL.Path, "/api/admin/account/passkeys/"), "/"), 10, 64)
	if err != nil || id <= 0 {
		httpx.BadRequest(w, "bad passkey id")
		return
	}
	owner, err := a.Store.EnsureOwner(a.cfg().AdminUser)
	if err != nil {
		httpx.ServerError(w, err)
		return
	}
	if err := a.Store.DeletePasskey(id, owner.ID); err != nil {
		if errors.Is(err, store.ErrNotFound) {
			httpx.NotFound(w)
			return
		}
		httpx.ServerError(w, err)
		return
	}
	httpx.OK(w, map[string]any{"ok": true})
}