/*
 * KIELER - Kiel Integrated Environment for Layout Eclipse RichClient
 *
 * http://rtsys.informatik.uni-kiel.de/kieler
 *
 * Copyright 2021 by
 * + Kiel University
 *   + Department of Computer Science
 *     + Real-Time and Embedded Systems Group
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License 2.0 which is available at
 * http://www.eclipse.org/legal/epl-2.0.
 *
 * SPDX-License-Identifier: EPL-2.0
 */

import { inject, injectable, postConstruct } from 'inversify'
import {
    ActionHandlerRegistry,
    IActionDispatcher,
    IActionHandler,
    IActionHandlerInitializer,
    ICommand,
    TYPES,
} from 'sprotty'
import { Action } from 'sprotty-protocol'
import { PersistenceStorage, ServiceTypes } from '../services'
import {
    ResetLayoutOptionsAction,
    ResetRenderOptionsAction,
    ResetSynthesisOptionsAction,
    SetLayoutOptionsAction,
    SetRenderOptionAction,
    SetSynthesisOptionsAction,
} from './actions'

/**
 * {@link IActionHandler} that handles update actions for various options.
 * This handler persists the updates so they will still be available when a user
 * closes and reopens the diagram view.
 */
@injectable()
export class OptionsPersistence implements IActionHandler, IActionHandlerInitializer {
    @inject(ServiceTypes.PersistenceStorage) private storage: PersistenceStorage

    @inject(TYPES.IActionDispatcher) private dispatcher: IActionDispatcher

    @postConstruct()
    init(): void {
        this.storage.onClear(this.handleClear.bind(this))
    }

    initialize(registry: ActionHandlerRegistry): void {
        registry.register(SetRenderOptionAction.KIND, this)
        registry.register(SetLayoutOptionsAction.KIND, this)
        registry.register(SetSynthesisOptionsAction.KIND, this)
    }

    handle(action: Action): void | Action | ICommand {
        if (SetRenderOptionAction.isThisAction(action)) {
            this.storage.setItem<Record<string, unknown>>('render', (prev) => {
                const obj = prev ?? {}
                obj[action.id] = action.value
                return obj
            })
        } else if (SetLayoutOptionsAction.isThisAction(action)) {
            this.storage.setItem<Record<string, unknown>>('layout', (prev) => {
                const obj = prev ?? {}
                for (const option of action.options) {
                    obj[option.optionId] = option.value
                }
                return obj
            })
        } else if (SetSynthesisOptionsAction.isThisAction(action)) {
            this.storage.setItem<Record<string, unknown>>('synthesis', (prev) => {
                const obj = prev ?? {}
                for (const option of action.options) {
                    obj[option.id] = option.currentValue
                }
                return obj
            })
        }
    }

    /** Reset all stored options when the storage gets cleared from outside. */
    private handleClear() {
        this.dispatcher.dispatch(ResetRenderOptionsAction.create())
        this.dispatcher.dispatch(ResetSynthesisOptionsAction.create())
        this.dispatcher.dispatch(ResetLayoutOptionsAction.create())
    }
}