wikimedia/mediawiki-extensions-Wikibase

import {
    DataValue,
    StatementMap,
} from '@wmde/wikibase-datamodel-types';
import StatementMutationError from '@/change-op/statement-mutation/StatementMutationError';
import { PathToSnak } from '@/store/statements/PathToSnak';
import EntityId from '@/datamodel/EntityId';
import StatementMutationStrategy from './StatementMutationStrategy';

export default class ReplaceMutationStrategy implements StatementMutationStrategy {
    public apply<T extends Record<EntityId, StatementMap>>(
        targetValue: DataValue,
        path: PathToSnak,
        state: T,
    ): T {
        // TODO other strategies may have similar needs, may move into a shared method (e.g. base class)
        const snak = path.resolveSnakInStatement( state );
        if ( snak === null ) {
            throw new Error( StatementMutationError.NO_SNAK_FOUND );
        }

        if ( snak.datavalue !== undefined && targetValue.type !== snak.datavalue.type ) {
            throw new Error( StatementMutationError.INCONSISTENT_PAYLOAD_TYPE );
        }

        snak.snaktype = 'value';

        snak.datavalue = targetValue;

        return state;
    }
}