import { IElementStackItem, IElementParams, IElementState, EventType, IPartialObserver, ElementId } from "../types";
import { Processor } from "../Processor";
import { EventsManager } from "../EventsManager";
import { CallbacksManager } from "../CallbacksManager";
import { mergeContexts } from "../util/mergeContexts";

export const createStackItem = (
    callbacksManager: CallbacksManager,
    eventsManager: EventsManager,
    processor: Processor,
    elementId: ElementId,
    state: IElementState,
    params: IElementParams,
    observer: IPartialObserver<any>,
) => {
    const elementCall: IElementStackItem = {
        args: params.args,
        func: params.func,
    };
    state.stack.push(elementCall);
    const newElementId = processor.createElement(params);
    state.currentCall = { elementId: newElementId };

    const callElementState = processor.getElementStateById(newElementId);
    callElementState.contexts = mergeContexts(state.contexts, state.tickState.contexts);
    eventsManager.triggerEvent({
        elementId: newElementId,
        type: EventType.Create,
        params: {},
        value: undefined,
    });

    callElementState.observer = {
        next: observer.next ? callbacksManager.addCallback(observer.next)[0] : undefined,
        error: observer.error
            ? callbacksManager.addCallback(observer.error)[0]
            : eventsManager.createEvent(elementId, EventType.CallError, {})[0],
        complete: eventsManager.createEvent(elementId, EventType.CallComplete, {})[0],
    };
};