const assert = require("assert");
const { Readable } = require("stream");
const { loadModule } = require("./_shared.cjs");

const tests = [];
const test = (name, fn) => tests.push({ name, fn });

const createRedirectRes = () => {
    const state = {
        redirectedTo: null,
        headers: {},
        piped: false,
        headersSent: false
    };

    return {
        state,
        get headersSent() {
            return state.headersSent;
        },
        setHeader(key, value) {
            state.headers[key.toLowerCase()] = value;
        },
        redirect(path) {
            state.redirectedTo = path;
            state.headersSent = true;
            return path;
        }
    };
};

test("documents download redirects when id/hash query is missing", async () => {
    const mod = loadModule("pages/api/documents/download/[id].js", {
        getToken: async () => ({ access_token: "tok" }),
        consoleLogger: () => {},
        axios: { get: async () => ({}) }
    });

    const req = { query: { id: "DOC-1" } };
    const res = createRedirectRes();

    await mod.default(req, res);

    assert.strictEqual(res.state.redirectedTo, "/filenotavailable");
});

test("documents download success sets attachment headers and pipes stream", async () => {
    const stream = new Readable({
        read() {}
    });

    const mod = loadModule("pages/api/documents/download/[id].js", {
        setTimeout: (fn) => {
            fn();
            return 0;
        },
        getToken: async () => ({ access_token: "tok" }),
        consoleLogger: () => {},
        axios: {
            get: async () => ({
                headers: {
                    "content-disposition": "attachment; filename=test-file.pdf"
                },
                data: stream
            })
        }
    });

    const req = { query: { id: "DOC-1", hash: "h1" } };
    const res = createRedirectRes();

    stream.pipe = (target) => {
        target.state.piped = true;
        target.state.headersSent = true;
        return target;
    };

    await mod.default(req, res);

    assert.strictEqual(
        res.state.headers["content-disposition"],
        "attachment; filename=test-file.pdf"
    );
    assert.strictEqual(
        res.state.headers["content-type"],
        "application/octet-stream"
    );
    assert.strictEqual(res.state.piped, true);
    assert.strictEqual(res.state.redirectedTo, null);
});

test("documents download redirects when relay request fails", async () => {
    const mod = loadModule("pages/api/documents/download/[id].js", {
        setTimeout: (fn) => {
            fn();
            return 0;
        },
        getToken: async () => ({ access_token: "tok" }),
        consoleLogger: () => {},
        axios: {
            get: async () => {
                throw new Error("relay failed");
            }
        }
    });

    const req = { query: { id: "DOC-1", hash: "h1" } };
    const res = createRedirectRes();

    await mod.default(req, res);

    assert.strictEqual(res.state.redirectedTo, "/filenotavailable");
});

const run = async () => {
    let passed = 0;
    for (const currentTest of tests) {
        await currentTest.fn();
        passed += 1;
    }

    console.log(
        `Phase 21 documents-handler contract tests passed (${passed}/${tests.length}).`
    );
};

module.exports = run;

if (require.main === module) {
    run().catch((error) => {
        console.error(error);
        process.exit(1);
    });
}