@gorpacrate/core-graphics/lib/history/history-reducer.js

A core library for creating shape-based graphic editors

"use strict";
exports.__esModule = true;
var i = require("icepick");
var history_event_1 = require("../history/history-event");
var math_1 = require("../utils/math");
function getWantedIndex(params) {
    var relative = params.relative, length = params.length, current = params.current, value = params.value;
    if (relative) {
        var unpadded = current + value;
        if (unpadded <= 0) {
            return 0;
        }
        if (unpadded >= (length - 1)) {
            return length - 1;
        }
        return unpadded;
    }
    return math_1.modulus(value, length);
}
exports.INITIAL_SCENE = {
    shapes: {},
    shapesOrder: []
};
// persisted events
function reducePersistedHistoryToScene(history, initialScene) {
    if (initialScene === void 0) { initialScene = exports.INITIAL_SCENE; }
    if (history.length === 0) {
        return initialScene;
    }
    return history.reduce(function (scene, persistedEvent) {
        if (!persistedEvent.applied) {
            return scene;
        }
        return reducer(scene, history_event_1.getHistoryEventFromPersisted(persistedEvent));
    }, initialScene);
}
exports["default"] = reducePersistedHistoryToScene;
// unpersisted events
function reduceHistoryEventsToScene(history, initialScene) {
    if (initialScene === void 0) { initialScene = exports.INITIAL_SCENE; }
    if (history.length === 0) {
        return initialScene;
    }
    return history.reduce(reducer, initialScene);
}
exports.reduceHistoryEventsToScene = reduceHistoryEventsToScene;
// unpersisted events reducer
function reducer(scene, event) {
    var shapes = scene.shapes, shapesOrder = scene.shapesOrder;
    if (history_event_1.isShapeAddEvent(event)) {
        var addId = event.payload.id;
        var nextShapes = i.assoc(shapes, addId, event.payload);
        var nextShapesOrder = i.push(shapesOrder, addId);
        return i.chain(scene)
            .assoc('shapes', nextShapes)
            .assoc('shapesOrder', nextShapesOrder)
            .value();
    }
    if (history_event_1.isShapeUpdateEvent(event)) {
        var _a = event.payload, updateId = _a.id, shapeData = _a.shapeData;
        if (!scene.shapes[updateId]) {
            return scene;
        }
        var nextShapes = i.assoc(shapes, updateId, shapeData);
        return i.assoc(scene, 'shapes', nextShapes);
    }
    if (history_event_1.isShapeRemoveEvent(event)) {
        var removeId_1 = event.payload.id;
        if (!shapes[removeId_1]) {
            return scene;
        }
        var nextShapes = i.dissoc(shapes, removeId_1);
        var nextShapesOrder = i.filter(function (id) { return (id !== removeId_1); }, shapesOrder);
        return i.chain(scene)
            .assoc('shapes', nextShapes)
            .assoc('shapesOrder', nextShapesOrder)
            .value();
    }
    if (history_event_1.isShapeChangeOrderEvent(event)) {
        var castEvent = event;
        var _b = castEvent.payload, id = _b.id, value = _b.value, relative = _b.relative;
        var newOrder = i.thaw(shapesOrder);
        var length_1 = newOrder.length;
        var currentIndex = newOrder.indexOf(id);
        var wantedIndex = getWantedIndex({ relative: relative, length: length_1, current: currentIndex, value: value });
        if (wantedIndex > currentIndex) {
            newOrder.splice(wantedIndex + 1, 0, id);
            newOrder.splice(currentIndex, 1);
        }
        else {
            newOrder.splice(currentIndex, 1);
            newOrder.splice(wantedIndex, 0, id);
        }
        return i.assoc(scene, 'shapesOrder', newOrder);
    }
    if (event.type === 5 /* EraseAll */) {
        return {
            shapes: {},
            shapesOrder: []
        };
    }
    if (event.type === 6 /* Grouped */) {
        var events = event.payload;
        return events.reduce(reducer, scene);
    }
    return scene;
}
exports.reducer = reducer;
//# sourceMappingURL=history-reducer.js.map