import type { Item } from '../fs/Item'
import type { SimpleStream } from '../utils/SimpleStream'
import { Program } from './Program'

export class Eval extends Program {
    async Exec(stdin: SimpleStream<string>, stdout: SimpleStream<string>, _workdir: Item, args: string[]): Promise<number> {
        const inlineArgs = args.slice(1)
        const source = inlineArgs.length > 0
            ? inlineArgs.join(' ')
            : await stdin.wait()

        if (source.trim().length === 0) {
            stdout.emit('eval: error: missing javascript input\n')
            return 1
        }

        try {
            this.RunJs(source, stdout)
        } catch {
            return 1
        }

        return 0
    }

    private RunJs(javascript: string, stdout: SimpleStream<string>) {
        try {
            // todo: pass workdir to the program
            eval(javascript)
        } catch (e) {
            stdout.emit(`${String(e)}\n`)
            throw e
        }
    }
}