import {entity, Entity} from "../utils/entity";
import {
    Command,
    CommandRegistry,
    CommandRunnerContext,
    CommandRunnerContextExport,
    CommandSchema,
    createCommandRegistry,
    createCommandRunnerContext,
    parseCommandSchema,
    registerCommand
} from "../utils/command";

export interface IGameContext<TState extends Record<string, unknown> = {} > {
    state: Entity<TState>;
    commands: CommandRunnerContextExport<Entity<TState>>;
}

export function createGameContext<TState extends Record<string, unknown> = {} >(
    commandRegistry: CommandRegistry<Entity<TState>>,
    initialState?: TState | (() => TState)
): IGameContext<TState> {
    const stateValue = typeof initialState === 'function' ? initialState() : initialState ?? {} as TState;
    const state = entity('state', stateValue);
    const commands = createCommandRunnerContext(commandRegistry, state);

    return {
        state,
        commands
    };
}

/**
 * so that we can do `import * as tictactoe from './tic-tac-toe.ts';\n\n createGameContextFromModule(tictactoe);`
 * @param module
 */
export function createGameContextFromModule<TState extends Record<string, unknown> = {} >(
    module: {
        registry: CommandRegistry<Entity<TState>>,
        createInitialState: () => TState
    },
): IGameContext<TState> {
    return createGameContext(module.registry, module.createInitialState);
}

export function createGameCommandRegistry<TState extends Record<string, unknown> = {} >() {
    const registry = createCommandRegistry<Entity<TState>>();
    return {
        registry,
        add<TResult = unknown>(
            schema: CommandSchema | string,
            run: (this: CommandRunnerContext<Entity<TState>>, command: Command) => Promise<TResult>
        ){
            createGameCommand(registry, schema, run);
            return this;
        }
    }
}

export function createGameCommand<TState extends Record<string, unknown> = {} , TResult = unknown>(
    registry: CommandRegistry<Entity<TState>>,
    schema: CommandSchema | string,
    run: (this: CommandRunnerContext<Entity<TState>>, command: Command) => Promise<TResult>
) {
    registerCommand(registry, {
        schema: typeof schema === 'string' ? parseCommandSchema(schema) : schema,
        run,
    });
}