import { describe, expect, it } from "@suaveplan/testing/runner";

import { DMP_CODES, DmpError, type DmpErrorCode } from "../src/error-codes.js";

describe("@suaveplan/drive-mesh-protocol — DMP_CODES registry", () => {
    it("is frozen", { timeout: 5000 }, () => {
        expect(Object.isFrozen(DMP_CODES)).toBe(true);
    });

    it("every code value starts with the DMP. namespace", {
        timeout: 5000,
    }, () => {
        for (const value of Object.values(DMP_CODES)) {
            expect(value).toMatch(/^DMP\./);
        }
    });

    it("includes every documented rejection path", { timeout: 5000 }, () => {
        const expected = [
            "EMPTY_REQUEST",
            "UNKNOWN_REQUEST_KIND",
            "MAX_CHUNKS_EXCEEDED",
            "BITSET_LENGTH_MISMATCH",
            "BITSET_PADDING_NONZERO",
            "UNORDERED_RESPONSE",
            "GENERATION_STALE",
            "CODEC_MISMATCH",
        ] as const;
        for (const key of expected) {
            expect(DMP_CODES).toHaveProperty(key);
        }
    });
});

describe("@suaveplan/drive-mesh-protocol — DmpError class", () => {
    it("preserves the code", { timeout: 5000 }, () => {
        const err = new DmpError(DMP_CODES.EMPTY_REQUEST, "test message");
        expect(err.code).toBe(DMP_CODES.EMPTY_REQUEST);
        expect(err.message).toBe("test message");
    });

    it("threads cause and context through SuaveplanError options", {
        timeout: 5000,
    }, () => {
        const cause = new Error("inner");
        const err = new DmpError(
            DMP_CODES.MAX_CHUNKS_EXCEEDED,
            "cap exceeded",
            {
                cause,
                context: { requested: 4096, allowed: 1024 },
            }
        );
        expect(err.cause).toBe(cause);
        expect(err.context).toEqual({ requested: 4096, allowed: 1024 });
    });

    it("permits all codes via DmpErrorCode union", { timeout: 5000 }, () => {
        // Type-level check: every code is assignable to the discriminator.
        const codes: DmpErrorCode[] = Object.values(DMP_CODES);
        expect(codes.length).toBeGreaterThanOrEqual(8);
        for (const code of codes) {
            const err = new DmpError(code, "ok");
            expect(err.code).toBe(code);
        }
    });
});