impost/example-app/server/utils/config.ts

import { readFileSync } from 'fs';
import { load } from 'js-toml';
import z from 'zod';
import { ChallengeAlgorithm, ChallengeStrategy } from "@impost/lib";

const SHA256Schema = z.discriminatedUnion("strategy", [
    z.object({
        algorithm: z.literal(ChallengeAlgorithm.SHA256),
        strategy: z.literal(ChallengeStrategy.LeadingZeroes),
        leading_zeroes: z.object({
            difficulty: z.number().int().min(1).max(64),
        }),
    }),
    z.object({
        algorithm: z.literal(ChallengeAlgorithm.SHA256),
        strategy: z.literal(ChallengeStrategy.TargetNumber),
        target_number: z.object({
            max_number: z.number().int().min(1).max(100_000),
        }),
    }),
]);

const Argon2idSchema = z.discriminatedUnion("strategy", [
    z.object({
        algorithm: z.literal(ChallengeAlgorithm.Argon2id),
        strategy: z.literal(ChallengeStrategy.LeadingZeroes),
        leading_zeroes: z.object({
            difficulty: z.number().int().min(1).max(64),
        }),
    }),
    z.object({
        algorithm: z.literal(ChallengeAlgorithm.Argon2id),
        strategy: z.literal(ChallengeStrategy.TargetNumber),
        target_number: z.object({
            max_number: z.number().int().min(1).max(100_000),
        }),
    }),
]);

const KCTFSchema = z.object({
    algorithm: z.literal(ChallengeAlgorithm.kCTF),
    kctf: z.object({
        difficulty: z.number().int().min(1),
    }),
});

export const Config = z.union([SHA256Schema, Argon2idSchema, KCTFSchema]);

export type Config = z.infer<typeof Config>;

export let config: Config;

try {
    config = Config.parse(load(readFileSync('./config.toml', 'utf-8')));
} catch (error: any) {
    if (error instanceof z.ZodError) {
        console.error("Failed to parse config:");
        for (const issue of error.issues) {
            console.error(issue.message, issue.path);
        }
    } else {
        console.error("Failed to parse config:", error);
    }
    process.exit(1);
}