import { SetOptionHandler } from "./setHandler.js";

export class CommandExecutor {
    commandBar;
    #history = [];
    #handlers = new Map();

    constructor(commandBar) {
        this.commandBar = commandBar;
        console.log(this.#handlers);
        this.addHandler(new SetOptionHandler());
        console.log(this.#handlers);
    }

    addHandler(handler) {
        this.#handlers.set(handler.name, handler);
    }

    executeCommand(command) {
        this.appendCommandToHistory(command);

        const handler = this.#handlerForCommand(command);
        if (!handler) {
            throw new Error(`No handler for '${command.verb.valueOf()}' command`);
        }

        let result;
        try {
            result = handler.execute(command, this.commandBar);
        } catch (e) {
            result = null;
        }

        if (result !== undefined && !result) {
            console.error(`Command failed: ${command}`);
        }
    }

    #handlerForCommand(command) {
        const verb = command.verb.valueOf();
        return this.#handlers.get(verb);
    }

    // MARK: History

    get historyLength() {
        return this.#history.length;
    }

    appendCommandToHistory(command) {
        this.#history.push(command);
    }

    commandAtHistoryIndex(index) {
        return this.#history[index];
    }
}