package auth

import (
	"fmt"

	"git.phc.dm.unipi.it/phc/website/model"
	"git.phc.dm.unipi.it/phc/website/util"
)

var exampleMemoryUsers = &Memory{
	Users: map[string]*memoryUser{
		"aziis98": {
			User: model.User{
				Username: "aziis98",
				Name:     "Antonio",
				Surname:  "De Lucreziis",
				Email:    "aziis98@example.org",
			}.WithDefaultFullName(),
			Password: "123",
		},
		"bachoseven": {
			User: model.User{
				Username: "bachoseven",
				Name:     "Francesco",
				Surname:  "Minnocci",
				Email:    "bachoseven@example.org",
			}.WithDefaultFullName(),
			Password: "234",
		},
	},
	Sessions: map[string]*memorySession{},
}

type memoryUser struct {
	model.User
	Password string `json:"-"`
}

func (u memoryUser) AsUser() *model.User {
	return &model.User{
		Username: u.Username,
		Name:     u.Name,
		Surname:  u.Surname,
		FullName: u.FullName,
		Email:    u.Email,
	}
}

type memorySession struct {
	Username string
	Token    string
}

func (s memorySession) AsSession() *model.Session {
	return &model.Session{
		Username: s.Username,
		Token:    s.Token,
	}
}

type Memory struct {
	Users    map[string]*memoryUser
	Sessions map[string]*memorySession
}

func (m *Memory) GetUser(username string) (*model.User, error) {
	user, ok := m.Users[username]
	if !ok {
		return nil, fmt.Errorf(`no user with that username`)
	}

	return user.AsUser(), nil
}

func (m *Memory) GetUsers() ([]*model.User, error) {
	users := make([]*model.User, len(m.Users))
	i := 0
	for _, u := range m.Users {
		users[i] = u.AsUser()
		i++
	}

	return users, nil
}

func (m *Memory) GetSession(token string) (*model.Session, error) {
	session, ok := m.Sessions[token]
	if !ok {
		return nil, ErrInvalidSession
	}

	return session.AsSession(), nil
}

func (m *Memory) Login(username string, password string) (*model.Session, error) {
	user, ok := m.Users[username]
	if !ok {
		return nil, fmt.Errorf(`no user with that username`)
	}

	if user.Password != password {
		return nil, fmt.Errorf(`invalid credentials`)
	}

	session := &memorySession{username, util.GenerateRandomString(15)}
	m.Sessions[session.Token] = session

	return session.AsSession(), nil
}