package main

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

	"github.com/go-chi/chi/v5"
)

type APIError struct {
	Error string `json:"error"`
}

// since we only have the single username to worry about, we just wrap everything up here
func UserExistsMiddleware(user string, h http.HandlerFunc) http.HandlerFunc {
	return func(w http.ResponseWriter, r *http.Request) {
		userID := chi.URLParam(r, "user")
		if userID != user {
			RespondJSON(w, APIError{Error: "account not found"}, http.StatusNotFound)
			return
		}
		h.ServeHTTP(w, r)
	}
}

func RespondJSON(w http.ResponseWriter, content any, statuscode int) {
	b, err := json.Marshal(content)
	if err != nil {
		w.WriteHeader(http.StatusInternalServerError)
		return
	}
	w.WriteHeader(statuscode)
	w.Write(b)
}

func WebFingerHandler(wf *Webfinger) http.HandlerFunc {
	return func(w http.ResponseWriter, r *http.Request) {
		requestedResource := r.URL.Query().Get("resource")
		res, err := wf.FingerResource(requestedResource)
		if err != nil {
			RespondJSON(w, APIError{Error: "account not found"}, http.StatusNotFound)
			return
		}
		RespondJSON(w, res, http.StatusOK)
	}
}

func ProfileHandler(pp *ProfileProvider) http.HandlerFunc {
	return func(w http.ResponseWriter, r *http.Request) {
		res, err := pp.Get()
		if err != nil {
			RespondJSON(w, APIError{Error: "account not found"}, http.StatusNotFound)
			return
		}
		RespondJSON(w, res, http.StatusOK)
	}
}

// client retrieves messages for user
func GetInboxHandler(streams *InMemoryStreams) http.HandlerFunc {
	return func(w http.ResponseWriter, r *http.Request) {
		stream, err := streams.GetActivitiesToUser()
		if err != nil {
			RespondJSON(w, APIError{Error: err.Error()}, http.StatusInternalServerError)
			return
		}
		RespondJSON(w, stream, http.StatusOK)
	}
}

// handle incoming activities for user
func PostInboxHandler(streams *InMemoryStreams) http.HandlerFunc {
	return func(w http.ResponseWriter, r *http.Request) {
		err := streams.AddActivityToUser()
		if err != nil {
			RespondJSON(w, APIError{Error: err.Error()}, http.StatusInternalServerError)
			return
		}
		RespondJSON(w, nil, http.StatusOK)
	}
}

// other servers/clients read a user's activities
func GetOutboxHandler(streams *InMemoryStreams) http.HandlerFunc {
	return func(w http.ResponseWriter, r *http.Request) {
		stream, err := streams.GetActivitiesFromUser()
		if err != nil {
			RespondJSON(w, APIError{Error: err.Error()}, http.StatusInternalServerError)
			return
		}
		RespondJSON(w, stream, http.StatusOK)
	}
}

// client adds new activity for user
func PostOutboxHandler(streams *InMemoryStreams) http.HandlerFunc {
	return func(w http.ResponseWriter, r *http.Request) {
		err := streams.AddActivityFromUser()
		if err != nil {
			RespondJSON(w, APIError{Error: err.Error()}, http.StatusInternalServerError)
			return
		}
		RespondJSON(w, nil, http.StatusOK)
	}
}