// Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved.
// See LICENSE.txt for license information.

package sqlstore

import (
	"strconv"
	"strings"

	"github.com/mattermost/mattermost-server/v5/model"
	"github.com/mattermost/mattermost-server/v5/store"

	"github.com/pkg/errors"
)

type SqlComplianceStore struct {
	SqlStore
}

func newSqlComplianceStore(sqlStore SqlStore) store.ComplianceStore {
	s := &SqlComplianceStore{sqlStore}

	for _, db := range sqlStore.GetAllConns() {
		table := db.AddTableWithName(model.Compliance{}, "Compliances").SetKeys(false, "Id")
		table.ColMap("Id").SetMaxSize(26)
		table.ColMap("UserId").SetMaxSize(26)
		table.ColMap("Status").SetMaxSize(64)
		table.ColMap("Desc").SetMaxSize(512)
		table.ColMap("Type").SetMaxSize(64)
		table.ColMap("Keywords").SetMaxSize(512)
		table.ColMap("Emails").SetMaxSize(1024)
	}

	return s
}

func (s SqlComplianceStore) createIndexesIfNotExists() {
}

func (s SqlComplianceStore) Save(compliance *model.Compliance) (*model.Compliance, error) {
	compliance.PreSave()
	if err := compliance.IsValid(); err != nil {
		return nil, err
	}

	if err := s.GetMaster().Insert(compliance); err != nil {
		return nil, errors.Wrap(err, "failed to save Compliance")
	}
	return compliance, nil
}

func (s SqlComplianceStore) Update(compliance *model.Compliance) (*model.Compliance, error) {
	if err := compliance.IsValid(); err != nil {
		return nil, err
	}

	if _, err := s.GetMaster().Update(compliance); err != nil {
		return nil, errors.Wrap(err, "failed to update Compliance")
	}
	return compliance, nil
}

func (s SqlComplianceStore) GetAll(offset, limit int) (model.Compliances, error) {
	query := "SELECT * FROM Compliances ORDER BY CreateAt DESC LIMIT :Limit OFFSET :Offset"

	var compliances model.Compliances
	if _, err := s.GetReplica().Select(&compliances, query, map[string]interface{}{"Offset": offset, "Limit": limit}); err != nil {
		return nil, errors.Wrap(err, "failed to find all Compliances")
	}
	return compliances, nil
}

func (s SqlComplianceStore) Get(id string) (*model.Compliance, error) {
	obj, err := s.GetReplica().Get(model.Compliance{}, id)
	if err != nil {
		return nil, errors.Wrapf(err, "failed to get Compliance with id=%s", id)
	}
	if obj == nil {
		return nil, store.NewErrNotFound("Compliance", id)
	}
	return obj.(*model.Compliance), nil
}

func (s SqlComplianceStore) ComplianceExport(job *model.Compliance) ([]*model.CompliancePost, error) {
	props := map[string]interface{}{"StartTime": job.StartAt, "EndTime": job.EndAt}

	keywordQuery := ""
	keywords := strings.Fields(strings.TrimSpace(strings.ToLower(strings.Replace(job.Keywords, ",", " ", -1))))
	if len(keywords) > 0 {

		keywordQuery = "AND ("

		for index, keyword := range keywords {
			keyword = sanitizeSearchTerm(keyword, "\\")
			if index >= 1 {
				keywordQuery += " OR LOWER(Posts.Message) LIKE :Keyword" + strconv.Itoa(index)
			} else {
				keywordQuery += "LOWER(Posts.Message) LIKE :Keyword" + strconv.Itoa(index)
			}

			props["Keyword"+strconv.Itoa(index)] = "%" + keyword + "%"
		}

		keywordQuery += ")"
	}

	emailQuery := ""
	emails := strings.Fields(strings.TrimSpace(strings.ToLower(strings.Replace(job.Emails, ",", " ", -1))))
	if len(emails) > 0 {

		emailQuery = "AND ("

		for index, email := range emails {
			if index >= 1 {
				emailQuery += " OR Users.Email = :Email" + strconv.Itoa(index)
			} else {
				emailQuery += "Users.Email = :Email" + strconv.Itoa(index)
			}

			props["Email"+strconv.Itoa(index)] = email
		}

		emailQuery += ")"
	}

	query :=
		`(SELECT
			Teams.Name AS TeamName,
			Teams.DisplayName AS TeamDisplayName,
			Channels.Name AS ChannelName,
			Channels.DisplayName AS ChannelDisplayName,
			Channels.Type AS ChannelType,
			Users.Username AS UserUsername,
			Users.Email AS UserEmail,
			Users.Nickname AS UserNickname,
			Posts.Id AS PostId,
			Posts.CreateAt AS PostCreateAt,
			Posts.UpdateAt AS PostUpdateAt,
			Posts.DeleteAt AS PostDeleteAt,
			Posts.RootId AS PostRootId,
			Posts.ParentId AS PostParentId,
			Posts.OriginalId AS PostOriginalId,
			Posts.Message AS PostMessage,
			Posts.Type AS PostType,
			Posts.Props AS PostProps,
			Posts.Hashtags AS PostHashtags,
			Posts.FileIds AS PostFileIds,
			Bots.UserId IS NOT NULL AS IsBot
		FROM
			Teams,
			Channels,
			Users,
			Posts
        LEFT JOIN Bots ON Bots.UserId = Posts.UserId
		WHERE
			Teams.Id = Channels.TeamId
				AND Posts.ChannelId = Channels.Id
				AND Posts.UserId = Users.Id
				AND Posts.CreateAt > :StartTime
				AND Posts.CreateAt <= :EndTime
				` + emailQuery + `
				` + keywordQuery + `)
		UNION ALL
		(SELECT
			'direct-messages' AS TeamName,
			'Direct Messages' AS TeamDisplayName,
			Channels.Name AS ChannelName,
			Channels.DisplayName AS ChannelDisplayName,
			Channels.Type AS ChannelType,
			Users.Username AS UserUsername,
			Users.Email AS UserEmail,
			Users.Nickname AS UserNickname,
			Posts.Id AS PostId,
			Posts.CreateAt AS PostCreateAt,
			Posts.UpdateAt AS PostUpdateAt,
			Posts.DeleteAt AS PostDeleteAt,
			Posts.RootId AS PostRootId,
			Posts.ParentId AS PostParentId,
			Posts.OriginalId AS PostOriginalId,
			Posts.Message AS PostMessage,
			Posts.Type AS PostType,
			Posts.Props AS PostProps,
			Posts.Hashtags AS PostHashtags,
			Posts.FileIds AS PostFileIds,
			Bots.UserId IS NOT NULL AS IsBot
		FROM
			Channels,
			Users,
			Posts
		LEFT JOIN Bots ON Bots.UserId = Posts.UserId
		WHERE
			Channels.TeamId = ''
				AND Posts.ChannelId = Channels.Id
				AND Posts.UserId = Users.Id
				AND Posts.CreateAt > :StartTime
				AND Posts.CreateAt <= :EndTime
				` + emailQuery + `
				` + keywordQuery + `)
		ORDER BY PostCreateAt
		LIMIT 30000`

	var cposts []*model.CompliancePost

	if _, err := s.GetReplica().Select(&cposts, query, props); err != nil {
		return nil, errors.Wrap(err, "unable to export compliance")
	}
	return cposts, nil
}

func (s SqlComplianceStore) MessageExport(after int64, limit int) ([]*model.MessageExport, error) {
	props := map[string]interface{}{"StartTime": after, "Limit": limit}
	query :=
		`SELECT
			Posts.Id AS PostId,
			Posts.CreateAt AS PostCreateAt,
			Posts.UpdateAt AS PostUpdateAt,
			Posts.DeleteAt AS PostDeleteAt,
			Posts.Message AS PostMessage,
			Posts.Type AS PostType,
			Posts.Props AS PostProps,
			Posts.OriginalId AS PostOriginalId,
			Posts.RootId AS PostRootId,
			Posts.Props AS PostProps,
			Posts.FileIds AS PostFileIds,
			Teams.Id AS TeamId,
			Teams.Name AS TeamName,
			Teams.DisplayName AS TeamDisplayName,
			Channels.Id AS ChannelId,
			CASE
				WHEN Channels.Type = 'D' THEN 'Direct Message'
				WHEN Channels.Type = 'G' THEN 'Group Message'
				ELSE Channels.DisplayName
			END AS ChannelDisplayName,
			Channels.Name AS ChannelName,
			Channels.Type AS ChannelType,
			Users.Id AS UserId,
			Users.Email AS UserEmail,
			Users.Username,
			Bots.UserId IS NOT NULL AS IsBot
		FROM
			Posts
		LEFT OUTER JOIN Channels ON Posts.ChannelId = Channels.Id
		LEFT OUTER JOIN Teams ON Channels.TeamId = Teams.Id
		LEFT OUTER JOIN Users ON Posts.UserId = Users.Id
		LEFT JOIN Bots ON Bots.UserId = Posts.UserId
		WHERE
			(Posts.CreateAt > :StartTime OR Posts.UpdateAt > :StartTime OR Posts.DeleteAt > :StartTime) AND
			Posts.Type NOT LIKE 'system_%'
		ORDER BY PostUpdateAt
		LIMIT :Limit`

	var cposts []*model.MessageExport
	if _, err := s.GetReplica().Select(&cposts, query, props); err != nil {
		return nil, errors.Wrap(err, "unable to export messages")
	}
	return cposts, nil
}