// Copyright 2016 The Gogs Authors. All rights reserved.
// Use of this source code is governed by a MIT-style
// license that can be found in the LICENSE file.

package models

import (
	"errors"
	"fmt"
	"strings"
)

var (
	// ErrEmailAddressNotExist email address not exist
	ErrEmailAddressNotExist = errors.New("Email address does not exist")
)

// EmailAddress is the list of all email addresses of a user. Can contain the
// primary email address, but is not obligatory.
type EmailAddress struct {
	ID          int64  `xorm:"pk autoincr"`
	UID         int64  `xorm:"INDEX NOT NULL"`
	Email       string `xorm:"UNIQUE NOT NULL"`
	IsActivated bool
	IsPrimary   bool `xorm:"-"`
}

// GetEmailAddresses returns all email addresses belongs to given user.
func GetEmailAddresses(uid int64) ([]*EmailAddress, error) {
	emails := make([]*EmailAddress, 0, 5)
	if err := x.
		Where("uid=?", uid).
		Find(&emails); err != nil {
		return nil, err
	}

	u, err := GetUserByID(uid)
	if err != nil {
		return nil, err
	}

	isPrimaryFound := false
	for _, email := range emails {
		if email.Email == u.Email {
			isPrimaryFound = true
			email.IsPrimary = true
		} else {
			email.IsPrimary = false
		}
	}

	// We always want the primary email address displayed, even if it's not in
	// the email address table (yet).
	if !isPrimaryFound {
		emails = append(emails, &EmailAddress{
			Email:       u.Email,
			IsActivated: true,
			IsPrimary:   true,
		})
	}
	return emails, nil
}

func isEmailUsed(e Engine, email string) (bool, error) {
	if len(email) == 0 {
		return true, nil
	}

	return e.Get(&EmailAddress{Email: email})
}

// IsEmailUsed returns true if the email has been used.
func IsEmailUsed(email string) (bool, error) {
	return isEmailUsed(x, email)
}

func addEmailAddress(e Engine, email *EmailAddress) error {
	email.Email = strings.ToLower(strings.TrimSpace(email.Email))
	used, err := isEmailUsed(e, email.Email)
	if err != nil {
		return err
	} else if used {
		return ErrEmailAlreadyUsed{email.Email}
	}

	_, err = e.Insert(email)
	return err
}

// AddEmailAddress adds an email address to given user.
func AddEmailAddress(email *EmailAddress) error {
	return addEmailAddress(x, email)
}

// AddEmailAddresses adds an email address to given user.
func AddEmailAddresses(emails []*EmailAddress) error {
	if len(emails) == 0 {
		return nil
	}

	// Check if any of them has been used
	for i := range emails {
		emails[i].Email = strings.ToLower(strings.TrimSpace(emails[i].Email))
		used, err := IsEmailUsed(emails[i].Email)
		if err != nil {
			return err
		} else if used {
			return ErrEmailAlreadyUsed{emails[i].Email}
		}
	}

	if _, err := x.Insert(emails); err != nil {
		return fmt.Errorf("Insert: %v", err)
	}

	return nil
}

// Activate activates the email address to given user.
func (email *EmailAddress) Activate() error {
	user, err := GetUserByID(email.UID)
	if err != nil {
		return err
	}
	if user.Rands, err = GetUserSalt(); err != nil {
		return err
	}

	sess := x.NewSession()
	defer sess.Close()
	if err = sess.Begin(); err != nil {
		return err
	}

	email.IsActivated = true
	if _, err := sess.
		ID(email.ID).
		Cols("is_activated").
		Update(email); err != nil {
		return err
	} else if err = updateUserCols(sess, user, "rands"); err != nil {
		return err
	}

	return sess.Commit()
}

// DeleteEmailAddress deletes an email address of given user.
func DeleteEmailAddress(email *EmailAddress) (err error) {
	var deleted int64
	// ask to check UID
	var address = EmailAddress{
		UID: email.UID,
	}
	if email.ID > 0 {
		deleted, err = x.ID(email.ID).Delete(&address)
	} else {
		deleted, err = x.
			Where("email=?", email.Email).
			Delete(&address)
	}

	if err != nil {
		return err
	} else if deleted != 1 {
		return ErrEmailAddressNotExist
	}
	return nil
}

// DeleteEmailAddresses deletes multiple email addresses
func DeleteEmailAddresses(emails []*EmailAddress) (err error) {
	for i := range emails {
		if err = DeleteEmailAddress(emails[i]); err != nil {
			return err
		}
	}

	return nil
}

// MakeEmailPrimary sets primary email address of given user.
func MakeEmailPrimary(email *EmailAddress) error {
	has, err := x.Get(email)
	if err != nil {
		return err
	} else if !has {
		return ErrEmailNotExist
	}

	if !email.IsActivated {
		return ErrEmailNotActivated
	}

	user := &User{ID: email.UID}
	has, err = x.Get(user)
	if err != nil {
		return err
	} else if !has {
		return ErrUserNotExist{email.UID, "", 0}
	}

	// Make sure the former primary email doesn't disappear.
	formerPrimaryEmail := &EmailAddress{Email: user.Email}
	has, err = x.Get(formerPrimaryEmail)
	if err != nil {
		return err
	}

	sess := x.NewSession()
	defer sess.Close()
	if err = sess.Begin(); err != nil {
		return err
	}

	if !has {
		formerPrimaryEmail.UID = user.ID
		formerPrimaryEmail.IsActivated = user.IsActive
		if _, err = sess.Insert(formerPrimaryEmail); err != nil {
			return err
		}
	}

	user.Email = email.Email
	if _, err = sess.ID(user.ID).Cols("email").Update(user); err != nil {
		return err
	}

	return sess.Commit()
}
