// gomuks - A terminal Matrix client written in Go.
// Copyright (C) 2018 Tulir Asokan
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

package main

import (
	"encoding/json"
	"io/ioutil"
	"path/filepath"

	"maunium.net/go/gomatrix"
)

type Session struct {
	MXID        string `json:"-"`
	path        string `json:"-"`
	AccessToken string
	NextBatch   string
	FilterID    string
	Rooms       map[string]*gomatrix.Room

	debug DebugPrinter `json:"-"`
}

func (config *Config) LoadSession(mxid string) {
	config.Session = config.NewSession(mxid)
	config.Session.Load()
}

func (config *Config) NewSession(mxid string) *Session {
	return &Session{
		MXID:  mxid,
		path:  filepath.Join(config.dir, mxid+".session"),
		Rooms: make(map[string]*gomatrix.Room),
		debug: config.debug,
	}
}

func (s *Session) Load() {
	data, err := ioutil.ReadFile(s.path)
	if err != nil {
		s.debug.Print("Failed to read session from", s.path)
		panic(err)
	}

	err = json.Unmarshal(data, s)
	if err != nil {
		s.debug.Print("Failed to parse session at", s.path)
		panic(err)
	}
}

func (s *Session) Save() {
	data, err := json.Marshal(s)
	if err != nil {
		s.debug.Print("Failed to marshal session of", s.MXID)
		panic(err)
	}

	err = ioutil.WriteFile(s.path, data, 0600)
	if err != nil {
		s.debug.Print("Failed to write session to", s.path)
		panic(err)
	}
}

func (s *Session) LoadFilterID(_ string) string {
	return s.FilterID
}

func (s *Session) LoadNextBatch(_ string) string {
	return s.NextBatch
}

func (s *Session) LoadRoom(mxid string) *gomatrix.Room {
	room, ok := s.Rooms[mxid]
	if !ok || room == nil {
		room := gomatrix.NewRoom(mxid)
		s.SaveRoom(room)
	}
	return room
}

func (s *Session) SaveFilterID(_, filterID string) {
	s.FilterID = filterID
	s.Save()
}

func (s *Session) SaveNextBatch(_, nextBatch string) {
	s.NextBatch = nextBatch
	s.Save()
}

func (s *Session) SaveRoom(room *gomatrix.Room) {
	s.Rooms[room.ID] = room
	s.Save()
}