// Copyright 2021 The Matrix.org Foundation C.I.C.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package cosmosdb

import (
	"context"
	"database/sql"
	"fmt"

	"github.com/matrix-org/dendrite/internal/cosmosdbapi"
	"github.com/matrix-org/dendrite/keyserver/storage/tables"
	"github.com/matrix-org/dendrite/keyserver/types"
	"github.com/matrix-org/gomatrixserverlib"
)

// var crossSigningKeysSchema = `
// CREATE TABLE IF NOT EXISTS keyserver_cross_signing_keys (
//     user_id TEXT NOT NULL,
// 	key_type INTEGER NOT NULL,
// 	key_data TEXT NOT NULL,
// 	PRIMARY KEY (user_id, key_type)
// );
// `

type crossSigningKeysCosmos struct {
	UserID  string `json:"user_id"`
	KeyType int64  `json:"key_type"`
	KeyData []byte `json:"key_data"`
}

type crossSigningKeysCosmosData struct {
	cosmosdbapi.CosmosDocument
	CrossSigningKeys crossSigningKeysCosmos `json:"mx_keyserver_cross_signing_keys"`
}

// "SELECT key_type, key_data FROM keyserver_cross_signing_keys" +
// " WHERE user_id = $1"
const selectCrossSigningKeysForUserSQL = "" +
	"select * from c where c._cn = @x1 " +
	"and c.mx_keyserver_cross_signing_keys.user_id = @x2 "

// const upsertCrossSigningKeysForUserSQL = "" +
// 	"INSERT OR REPLACE INTO keyserver_cross_signing_keys (user_id, key_type, key_data)" +
// 	" VALUES($1, $2, $3)"

type crossSigningKeysStatements struct {
	db                                *Database
	selectCrossSigningKeysForUserStmt string
	// upsertCrossSigningKeysForUserStmt *sql.Stmt
	tableName string
}

func (s *crossSigningKeysStatements) getCollectionName() string {
	return cosmosdbapi.GetCollectionName(s.db.databaseName, s.tableName)
}

func (s *crossSigningKeysStatements) getPartitionKey(userId string) string {
	uniqueId := userId
	return cosmosdbapi.GetPartitionKeyByUniqueId(s.db.cosmosConfig.TenantName, s.getCollectionName(), uniqueId)
}

func getCrossSigningKeys(s *crossSigningKeysStatements, ctx context.Context, pk string, docId string) (*crossSigningKeysCosmosData, error) {
	response := crossSigningKeysCosmosData{}
	err := cosmosdbapi.GetDocumentOrNil(
		s.db.connection,
		s.db.cosmosConfig,
		ctx,
		pk,
		docId,
		&response)

	if response.Id == "" {
		return nil, nil
	}

	return &response, err
}

func NewSqliteCrossSigningKeysTable(db *Database) (tables.CrossSigningKeys, error) {
	s := &crossSigningKeysStatements{
		db: db,
	}
	s.selectCrossSigningKeysForUserStmt = selectCrossSigningKeysForUserSQL
	// s.upsertCrossSigningKeysForUserStmt = upsertCrossSigningKeysForUserSQL
	s.tableName = "cross_signing_keys"
	return s, nil
}

func (s *crossSigningKeysStatements) SelectCrossSigningKeysForUser(
	ctx context.Context, txn *sql.Tx, userID string,
) (r types.CrossSigningKeyMap, err error) {
	// "SELECT key_type, key_data FROM keyserver_cross_signing_keys" +
	// " WHERE user_id = $1"
	params := map[string]interface{}{
		"@x1": s.getCollectionName(),
		"@x2": userID,
	}

	var rows []crossSigningKeysCosmosData
	err = cosmosdbapi.PerformQuery(ctx,
		s.db.connection,
		s.db.cosmosConfig.DatabaseName,
		s.db.cosmosConfig.ContainerName,
		s.getPartitionKey(userID), s.selectCrossSigningKeysForUserStmt, params, &rows)

	// rows, err := sqlutil.TxStmt(txn, s.selectCrossSigningKeysForUserStmt).QueryContext(ctx, userID)
	if err != nil {
		return nil, err
	}
	// defer internal.CloseAndLogIfError(ctx, rows, "selectCrossSigningKeysForUserStmt: rows.close() failed")
	r = types.CrossSigningKeyMap{}
	// for rows.Next() {
	for _, item := range rows {
		var keyTypeInt int16
		var keyData gomatrixserverlib.Base64Bytes
		// if err := rows.Scan(&keyTypeInt, &keyData); err != nil {
		// 	return nil, err
		// }
		keyData = item.CrossSigningKeys.KeyData
		keyTypeInt = int16(item.CrossSigningKeys.KeyType)
		keyType, ok := types.KeyTypeIntToPurpose[keyTypeInt]
		if !ok {
			return nil, fmt.Errorf("unknown key purpose int %d", keyTypeInt)
		}
		r[keyType] = keyData
	}
	return
}

func (s *crossSigningKeysStatements) UpsertCrossSigningKeysForUser(
	ctx context.Context, txn *sql.Tx, userID string, keyType gomatrixserverlib.CrossSigningKeyPurpose, keyData gomatrixserverlib.Base64Bytes,
) error {
	// "INSERT OR REPLACE INTO keyserver_cross_signing_keys (user_id, key_type, key_data)" +
	// " VALUES($1, $2, $3)"
	keyTypeInt, ok := types.KeyTypePurposeToInt[keyType]
	if !ok {
		return fmt.Errorf("unknown key purpose %q", keyType)
	}
	// 	PRIMARY KEY (user_id, key_type)
	docId := fmt.Sprintf("%s_%s", userID, keyType)
	cosmosDocId := cosmosdbapi.GetDocumentId(s.db.cosmosConfig.TenantName, s.getCollectionName(), docId)

	dbData, _ := getCrossSigningKeys(s, ctx, s.getPartitionKey(userID), cosmosDocId)
	if dbData != nil {
		dbData.SetUpdateTime()
		dbData.CrossSigningKeys.KeyData = keyData
	} else {
		data := crossSigningKeysCosmos{
			UserID:  userID,
			KeyType: int64(keyTypeInt),
			KeyData: keyData,
		}

		dbData = &crossSigningKeysCosmosData{
			CosmosDocument:   cosmosdbapi.GenerateDocument(s.getCollectionName(), s.db.cosmosConfig.TenantName, s.getPartitionKey(userID), cosmosDocId),
			CrossSigningKeys: data,
		}
	}
	// if _, err := sqlutil.TxStmt(txn, s.upsertCrossSigningKeysForUserStmt).ExecContext(ctx, userID, keyTypeInt, keyData); err != nil {
	// 	return fmt.Errorf("s.upsertCrossSigningKeysForUserStmt: %w", err)
	// }
	return cosmosdbapi.UpsertDocument(ctx,
		s.db.connection,
		s.db.cosmosConfig.DatabaseName,
		s.db.cosmosConfig.ContainerName,
		dbData.Pk,
		dbData)
}