index.js

var Immutable = require('immutable');

var KEY_SEPARATOR = '-';

function MultiDecorator(decorators) {
    this.decorators = Immutable.List(decorators);
}

/**
    Return list of decoration IDs per character

    @param {ContentBlock}
    @return {List<String>}
*/
MultiDecorator.prototype.getDecorations = function(block, contentState) {
    var decorations = Array(block.getText().length).fill(null);

    this.decorators.forEach(function(decorator, i) {
        var _decorations = decorator.getDecorations(block, contentState);

        _decorations.forEach(function(key, offset) {
            if (!key) {
                return;
            }

            key = i + KEY_SEPARATOR + key;

            decorations[offset] = key;
        });
    });

    return Immutable.List(decorations);
};

/**
    Return component to render a decoration

    @param {String}
    @return {Function}
*/
MultiDecorator.prototype.getComponentForKey = function(key) {
    var decorator = this.getDecoratorForKey(key);
    return decorator.getComponentForKey(
        this.getInnerKey(key)
    );
};

/**
    Return props to render a decoration

    @param {String}
    @return {Object}
*/
MultiDecorator.prototype.getPropsForKey = function(key) {
    var decorator = this.getDecoratorForKey(key);
    return decorator.getPropsForKey(
        this.getInnerKey(key)
    );
};

/**
    Return a decorator for a specific key

    @param {String}
    @return {Decorator}
*/
MultiDecorator.prototype.getDecoratorForKey = function(key) {
    var parts = key.split(KEY_SEPARATOR);
    var index = Number(parts[0]);

    return this.decorators.get(index);
};

/**
    Return inner key for a decorator

    @param {String}
    @return {String}
*/
MultiDecorator.prototype.getInnerKey = function(key) {
    var parts = key.split(KEY_SEPARATOR);
    return parts.slice(1).join(KEY_SEPARATOR);
};

module.exports = MultiDecorator;