/*
streamer-tools OBS Camera Plugin - API client tests
Copyright (C) 2026 CyberCoveLLC <jknapp85@gmail.com>

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0
*/

// Two layers of coverage:
//   1. a fake HttpClient, for response parsing and every error branch;
//   2. a real loopback HTTP server driven through the *platform* backend
//      (libcurl or WinHTTP), so the backend itself is exercised in CI on all
//      three runners rather than assumed to work.

#include <chrono>
#include <cstdio>
#include <memory>
#include <string>
#include <thread>
#include <vector>

#include "stplugin/api_client.h"
#include "stplugin/http.h"

#include "loopback_server.h"
#include "test_util.h"

using namespace stplugin;

namespace {

class FakeHttpClient : public HttpClient {
public:
    HttpResponse next;
    HttpRequest last;
    int calls = 0;

    HttpResponse send(const HttpRequest &request) override
    {
        last = request;
        ++calls;
        return next;
    }
};

ConnectionConfig testConfig()
{
    return ConnectionConfig{"https://streamers.example.com", "main-room", "readkey123"};
}

std::shared_ptr<FakeHttpClient> makeFake(long status, const std::string &body)
{
    auto fake = std::make_shared<FakeHttpClient>();
    fake->next.status = status;
    fake->next.body = body;
    return fake;
}

// ---------------------------------------------------------------------------
// URL handling
// ---------------------------------------------------------------------------

void testNormalizeServerUrl()
{
    ST_ASSERT_EQ(ApiClient::normalizeServerUrl("https://a.example.com"), std::string("https://a.example.com"));
    ST_ASSERT_EQ(ApiClient::normalizeServerUrl("https://a.example.com/"), std::string("https://a.example.com"));
    ST_ASSERT_EQ(ApiClient::normalizeServerUrl("https://a.example.com///"), std::string("https://a.example.com"));
    ST_ASSERT_EQ(ApiClient::normalizeServerUrl("  https://a.example.com  "), std::string("https://a.example.com"));
    // No scheme defaults to https, never http: the read key is a credential.
    ST_ASSERT_EQ(ApiClient::normalizeServerUrl("a.example.com"), std::string("https://a.example.com"));
    // An explicit http:// is honoured -- the test LXC is reachable that way.
    ST_ASSERT_EQ(ApiClient::normalizeServerUrl("http://192.168.1.175:3000"), std::string("http://192.168.1.175:3000"));
    ST_ASSERT_EQ(ApiClient::normalizeServerUrl(""), std::string(""));
    ST_ASSERT_EQ(ApiClient::normalizeServerUrl("   "), std::string(""));
    ST_ASSERT_EQ(ApiClient::normalizeServerUrl("https://"), std::string(""));
    ST_ASSERT_EQ(ApiClient::normalizeServerUrl("/"), std::string(""));
}

void testUrlEncodeAndRedaction()
{
    ST_ASSERT_EQ(urlEncode("plain-slug_1.0~"), std::string("plain-slug_1.0~"));
    ST_ASSERT_EQ(urlEncode("a b"), std::string("a%20b"));
    ST_ASSERT_EQ(urlEncode("a/b?c=d&e"), std::string("a%2Fb%3Fc%3Dd%26e"));
    ST_ASSERT_EQ(urlEncode("k\xc3\xa9y"), std::string("k%C3%A9y"));

    ST_ASSERT_EQ(ApiClient::redactedUrl("https://h/api/obs/r/slots?key=secret"),
                 std::string("https://h/api/obs/r/slots?key=***"));
    ST_ASSERT_EQ(ApiClient::redactedUrl("https://h/api/obs/r/slots?key=secret&x=1"),
                 std::string("https://h/api/obs/r/slots?key=***&x=1"));
    ST_ASSERT_EQ(ApiClient::redactedUrl("https://h/nothing"), std::string("https://h/nothing"));
}

void testRedactSensitiveParams()
{
    // The LiveKit log bridge's actual use case: a signaling URL embedded in
    // a free-form SDK log line, not a bare query string.
    ST_ASSERT_EQ(ApiClient::redactSensitiveParams(
                     "connecting to wss://lk.example.com/rtc?access_token=eyJhbGciOiJIUzI1NiJ9.abc.def&x=1"),
                 std::string("connecting to wss://lk.example.com/rtc?access_token=<redacted>&x=1"));

    // A value can be terminated by a quote or whitespace, not just '&', since
    // this scrubs arbitrary text rather than a URL/query string.
    ST_ASSERT_EQ(ApiClient::redactSensitiveParams("url=\"wss://h/rtc?access_token=secret\" state=connecting"),
                 std::string("url=\"wss://h/rtc?access_token=<redacted>\" state=connecting"));

    // "key=" is also scrubbed, matching redactedUrl's convention.
    ST_ASSERT_EQ(ApiClient::redactSensitiveParams("GET https://h/api/obs/r/slots?key=secret"),
                 std::string("GET https://h/api/obs/r/slots?key=<redacted>"));

    // Both params can appear in the same message, and each is independently
    // redacted.
    ST_ASSERT_EQ(
        ApiClient::redactSensitiveParams("a access_token=tok1 b key=tok2 c"),
        std::string("a access_token=<redacted> b key=<redacted> c"));

    // Text with neither parameter passes through unchanged.
    ST_ASSERT_EQ(ApiClient::redactSensitiveParams("livekit: participant joined"),
                 std::string("livekit: participant joined"));

    // A value at the very end of the string is still bounded correctly.
    ST_ASSERT_EQ(ApiClient::redactSensitiveParams("token was access_token=trailing"),
                 std::string("token was access_token=<redacted>"));
}

void testRequestShape()
{
    auto fake = makeFake(200, R"({"slots":[]})");
    ApiClient client(fake);
    ConnectionConfig config = testConfig();
    // Values that need encoding, and stray whitespace an operator would paste.
    config.room_slug = " main room ";
    config.read_key = " a+b/c ";
    (void)client.fetchSlots(config);
    ST_ASSERT_EQ(fake->last.method, std::string("GET"));
    ST_ASSERT_EQ(fake->last.url,
                 std::string("https://streamers.example.com/api/obs/main%20room/slots?key=a%2Bb%2Fc"));

    auto fake2 = makeFake(200, R"({"lkToken":"t","wsUrl":"wss://x","identity":"obs:r:1"})");
    ApiClient client2(fake2);
    (void)client2.requestToken(testConfig());
    ST_ASSERT_EQ(fake2->last.method, std::string("POST"));
    ST_ASSERT_EQ(fake2->last.url,
                 std::string("https://streamers.example.com/api/obs/main-room/token?key=readkey123"));
    ST_ASSERT_EQ(fake2->last.content_type, std::string("application/json"));
}

// ---------------------------------------------------------------------------
// Response parsing
// ---------------------------------------------------------------------------

void testSlotsHappyPath()
{
    auto fake = makeFake(200,
                         R"({"slots":[{"identity":"cam1","displayName":"Alice","live":true},)"
                         R"({"identity":"cam2","displayName":"Bob","live":false}]})");
    ApiClient client(fake);
    const SlotsResult result = client.fetchSlots(testConfig());
    ST_ASSERT(result.ok());
    ST_ASSERT_EQ(result.slots.size(), std::size_t(2));
    ST_ASSERT_EQ(result.slots[0].identity, std::string("cam1"));
    ST_ASSERT_EQ(result.slots[0].display_name, std::string("Alice"));
    ST_ASSERT_EQ(result.slots[0].live, true);
    ST_ASSERT_EQ(result.slots[1].live, false);
}

void testSlotsEdgeCases()
{
    // Empty room: a valid answer, not an error.
    {
        ApiClient client(makeFake(200, R"({"slots":[]})"));
        const SlotsResult result = client.fetchSlots(testConfig());
        ST_ASSERT(result.ok());
        ST_ASSERT_EQ(result.slots.size(), std::size_t(0));
    }
    // A missing/blank displayName falls back to the identity, matching what
    // the server itself does for a slot with no display_name.
    {
        ApiClient client(makeFake(200, R"({"slots":[{"identity":"cam1"},{"identity":"cam2","displayName":""}]})"));
        const SlotsResult result = client.fetchSlots(testConfig());
        ST_ASSERT(result.ok());
        ST_ASSERT_EQ(result.slots.size(), std::size_t(2));
        ST_ASSERT_EQ(result.slots[0].display_name, std::string("cam1"));
        ST_ASSERT_EQ(result.slots[1].display_name, std::string("cam2"));
        ST_ASSERT_EQ(result.slots[0].live, false); // missing `live` is not live
    }
    // An entry with no identity is unusable and is dropped, not surfaced as a
    // dropdown row that could never connect.
    {
        ApiClient client(makeFake(200, R"({"slots":[{"displayName":"ghost"},{"identity":"cam1"}]})"));
        const SlotsResult result = client.fetchSlots(testConfig());
        ST_ASSERT(result.ok());
        ST_ASSERT_EQ(result.slots.size(), std::size_t(1));
        ST_ASSERT_EQ(result.slots[0].identity, std::string("cam1"));
    }
    // Wrong types where the shape is otherwise right: don't crash, don't
    // invent values.
    {
        ApiClient client(makeFake(200, R"({"slots":[{"identity":"cam1","displayName":42,"live":"yes"}]})"));
        const SlotsResult result = client.fetchSlots(testConfig());
        ST_ASSERT(result.ok());
        ST_ASSERT_EQ(result.slots.size(), std::size_t(1));
        ST_ASSERT_EQ(result.slots[0].display_name, std::string("cam1"));
        ST_ASSERT_EQ(result.slots[0].live, false);
    }
}

void testTokenHappyPath()
{
    ApiClient client(makeFake(200,
                              R"({"lkToken":"eyJhbGciOiJIUzI1NiJ9.abc.def",)"
                              R"("wsUrl":"wss://streamers.example.com","identity":"obs:main-room:Ab_1"})"));
    const TokenResult result = client.requestToken(testConfig());
    ST_ASSERT(result.ok());
    ST_ASSERT_EQ(result.lk_token, std::string("eyJhbGciOiJIUzI1NiJ9.abc.def"));
    ST_ASSERT_EQ(result.ws_url, std::string("wss://streamers.example.com"));
    ST_ASSERT_EQ(result.identity, std::string("obs:main-room:Ab_1"));
}

void testHttpErrorStatuses()
{
    // 404 -- a wrong read key and an unknown slug are deliberately
    // indistinguishable server-side, so the message must not claim to know.
    {
        ApiClient client(makeFake(404, R"({"error":"not found"})"));
        const SlotsResult slots = client.fetchSlots(testConfig());
        ST_ASSERT(!slots.ok());
        ST_ASSERT(slots.status == ApiStatus::NotFound);
        ST_ASSERT_EQ(slots.slots.size(), std::size_t(0));

        const TokenResult token = client.requestToken(testConfig());
        ST_ASSERT(token.status == ApiStatus::NotFound);
        ST_ASSERT_EQ(token.lk_token, std::string(""));
    }
    // 503 -- server reachable, LiveKit not configured.
    {
        ApiClient client(makeFake(503, R"({"error":"livekit not configured"})"));
        ST_ASSERT(client.fetchSlots(testConfig()).status == ApiStatus::Unavailable);
        ST_ASSERT(client.requestToken(testConfig()).status == ApiStatus::Unavailable);
    }
    // Anything else, e.g. a reverse proxy answering before the app does.
    {
        ApiClient client(makeFake(502, "<html>502 Bad Gateway</html>"));
        const SlotsResult result = client.fetchSlots(testConfig());
        ST_ASSERT(result.status == ApiStatus::HttpError);
        ST_ASSERT_EQ(result.message, std::string("HTTP 502"));
    }
    {
        ApiClient client(makeFake(401, ""));
        ST_ASSERT(client.fetchSlots(testConfig()).status == ApiStatus::HttpError);
    }
}

void testMalformedSuccessBodies()
{
    // 200 with a body that is not the expected shape must be reported, not
    // silently treated as "no slots".
    const char *bad_slots[] = {
        "",
        "not json at all",
        "{}",
        R"({"slots":null})",
        R"({"slots":{}})",
        R"({"slots":"cam1"})",
        "[]",
        R"({"slots":[)",
        "<!DOCTYPE html><html>login page</html>",
    };
    for (const char *body : bad_slots) {
        ApiClient client(makeFake(200, body));
        const SlotsResult result = client.fetchSlots(testConfig());
        ST_ASSERT(result.status == ApiStatus::MalformedResponse);
        ST_ASSERT_EQ(result.slots.size(), std::size_t(0));
    }

    const char *bad_token[] = {
        "",
        "{}",
        R"({"lkToken":""})",
        R"({"lkToken":"t"})",                    // no wsUrl
        R"({"wsUrl":"wss://x"})",                // no token
        R"({"lkToken":123,"wsUrl":"wss://x"})",  // wrong type
        R"({"lkToken":"t","wsUrl":""})",
        "[]",
        "\xff\xfe binary",
    };
    for (const char *body : bad_token) {
        ApiClient client(makeFake(200, body));
        const TokenResult result = client.requestToken(testConfig());
        ST_ASSERT(result.status == ApiStatus::MalformedResponse);
        ST_ASSERT_EQ(result.lk_token, std::string(""));
    }
}

void testNetworkErrorAndInvalidConfig()
{
    {
        auto fake = std::make_shared<FakeHttpClient>();
        fake->next.network_error = "Could not resolve host";
        ApiClient client(fake);
        const SlotsResult result = client.fetchSlots(testConfig());
        ST_ASSERT(result.status == ApiStatus::NetworkError);
        ST_ASSERT_EQ(result.message, std::string("Could not resolve host"));
    }
    // An incomplete config must never reach the HTTP layer at all.
    {
        auto fake = makeFake(200, R"({"slots":[]})");
        ApiClient client(fake);
        ST_ASSERT(client.fetchSlots(ConnectionConfig{"", "r", "k"}).status == ApiStatus::InvalidConfig);
        ST_ASSERT(client.fetchSlots(ConnectionConfig{"https://h", "", "k"}).status == ApiStatus::InvalidConfig);
        ST_ASSERT(client.fetchSlots(ConnectionConfig{"https://h", "r", ""}).status == ApiStatus::InvalidConfig);
        ST_ASSERT(client.requestToken(ConnectionConfig{"https://", "r", "k"}).status == ApiStatus::InvalidConfig);
        ST_ASSERT_EQ(fake->calls, 0);
    }
    // A null HTTP client is a programming error, not a crash.
    {
        ApiClient client(nullptr);
        ST_ASSERT(client.fetchSlots(testConfig()).status == ApiStatus::InvalidConfig);
    }
}

// ---------------------------------------------------------------------------
// Real platform HTTP backend, against a real loopback socket
// ---------------------------------------------------------------------------

ConnectionConfig loopbackConfig(const sttest::LoopbackServer &server)
{
    return ConnectionConfig{server.baseUrl(), "main-room", "readkey123"};
}

void testPlatformBackendAgainstLoopback()
{
    std::shared_ptr<HttpClient> http(createPlatformHttpClient());
    ST_ASSERT(http != nullptr);
    if (!http)
        return;
    ApiClient client(http);

    // 200 with real slots, and the request line/headers the server sees.
    {
        sttest::LoopbackServer server([](const std::string &) {
            return sttest::httpResponse(200, "OK",
                                        R"({"slots":[{"identity":"cam1","displayName":"Alice","live":true}]})");
        });
        ST_ASSERT(server.valid());
        const SlotsResult result = client.fetchSlots(loopbackConfig(server));
        ST_ASSERT(result.ok());
        ST_ASSERT_EQ(result.slots.size(), std::size_t(1));
        ST_ASSERT_EQ(result.slots[0].identity, std::string("cam1"));
        ST_ASSERT(server.lastRequest().find("GET /api/obs/main-room/slots?key=readkey123") == 0);
    }

    // POST /token: verify the method and that a body is actually sent.
    {
        sttest::LoopbackServer server([](const std::string &) {
            return sttest::httpResponse(200, "OK", R"({"lkToken":"tok","wsUrl":"wss://lk.example","identity":"obs:r:1"})");
        });
        ST_ASSERT(server.valid());
        const TokenResult result = client.requestToken(loopbackConfig(server));
        ST_ASSERT(result.ok());
        ST_ASSERT_EQ(result.lk_token, std::string("tok"));
        ST_ASSERT_EQ(result.ws_url, std::string("wss://lk.example"));
        ST_ASSERT(server.lastRequest().find("POST /api/obs/main-room/token?key=readkey123") == 0);
    }

    // 404 and 503 over a real socket.
    {
        sttest::LoopbackServer server([](const std::string &) {
            return sttest::httpResponse(404, "Not Found", R"({"error":"not found"})");
        });
        ST_ASSERT(client.fetchSlots(loopbackConfig(server)).status == ApiStatus::NotFound);
    }
    {
        sttest::LoopbackServer server([](const std::string &) {
            return sttest::httpResponse(503, "Service Unavailable", R"({"error":"livekit not configured"})");
        });
        ST_ASSERT(client.requestToken(loopbackConfig(server)).status == ApiStatus::Unavailable);
    }

    // 200 with a truncated JSON body: must be MalformedResponse, not a hang
    // and not a crash.
    {
        sttest::LoopbackServer server([](const std::string &) {
            return sttest::httpResponse(200, "OK", R"({"slots":[{"identity":)");
        });
        ST_ASSERT(client.fetchSlots(loopbackConfig(server)).status == ApiStatus::MalformedResponse);
    }

    // A server that accepts the connection and closes without replying at
    // all. This is a network error, and it must come back promptly.
    {
        sttest::LoopbackServer server([](const std::string &) { return std::string(); });
        const auto start = std::chrono::steady_clock::now();
        const SlotsResult result = client.fetchSlots(loopbackConfig(server));
        const auto elapsed = std::chrono::steady_clock::now() - start;
        ST_ASSERT(result.status == ApiStatus::NetworkError);
        ST_ASSERT(std::chrono::duration_cast<std::chrono::seconds>(elapsed).count() < 15);
    }

    // Garbage that is not HTTP at all.
    {
        sttest::LoopbackServer server([](const std::string &) { return std::string("\x01\x02not http\r\n\r\n"); });
        const SlotsResult result = client.fetchSlots(loopbackConfig(server));
        ST_ASSERT(result.status == ApiStatus::NetworkError || result.status == ApiStatus::MalformedResponse ||
                  result.status == ApiStatus::HttpError);
    }

    // Nothing listening on the port at all: a clean NetworkError.
    {
        int dead_port = 0;
        {
            sttest::LoopbackServer server([](const std::string &) { return std::string(); });
            dead_port = server.port();
        } // server destroyed, port closed
        ConnectionConfig config{"http://127.0.0.1:" + std::to_string(dead_port), "main-room", "readkey123"};
        ST_ASSERT(client.fetchSlots(config).status == ApiStatus::NetworkError);
    }
}

void testPlatformBackendTimeout()
{
    // A server that accepts and then stalls. The plugin must give up on its
    // own timeout rather than blocking an OBS thread indefinitely.
    //
    // INSTRUMENTED (2026-09-09) while chasing an intermittent Windows-only
    // failure: on roughly 2 of 6 CI runs both assertions below fail together,
    // meaning the request waited out the full 5s stall and returned 200 --
    // the timeout did not fire at all. Same failure seen on 2026-09-07
    // (job 5834) and 2026-09-09 (job 5911), on identical code that passed on
    // other runs, so it is not a code change that caused it.
    //
    // The probe runs kProbes times and prints one line per attempt so a
    // single CI run yields a failure RATE and the WinHTTP error code, rather
    // than one bit. `ST_ASSERT` records and continues, so every attempt is
    // reported even when one fails. Remove the loop and this comment once the
    // mechanism is understood and fixed.
    constexpr int kProbes = 5;
    constexpr long long kStallMs = 5000;
    constexpr long kTimeoutMs = 700;

    int timed_out = 0;
    for (int i = 0; i < kProbes; ++i) {
        // A FRESH server per attempt, deliberately. `LoopbackServer` accepts
        // and handles one connection at a time on a single thread, so reusing
        // one server across attempts would leave attempts 2..n sitting in the
        // accept backlog -- a different scenario (never accepted) from the one
        // that fails on Windows (accepted, request read, then stalled).
        sttest::LoopbackServer server([kStallMs](const std::string &) {
            std::this_thread::sleep_for(std::chrono::milliseconds(kStallMs));
            return sttest::httpResponse(200, "OK", R"({"slots":[]})");
        });
        ST_ASSERT(server.valid());

        std::shared_ptr<HttpClient> http(createPlatformHttpClient());
        HttpRequest request;
        request.url = server.baseUrl() + "/api/obs/main-room/slots?key=k";
        request.timeout_ms = kTimeoutMs;

        const auto start = std::chrono::steady_clock::now();
        const HttpResponse response = http->send(request);
        const auto elapsed = std::chrono::steady_clock::now() - start;
        const long long ms = std::chrono::duration_cast<std::chrono::milliseconds>(elapsed).count();

        // 4000 was the old bound, chosen when nothing bounded the wait. The
        // code now promises a hard ceiling of 2x the caller's budget
        // (RequestDeadline in http_winhttp.cpp), so assert THAT -- 1400ms
        // here, plus slack for a loaded runner. This is also the only signal
        // that survives a green run: CTest prints nothing on success, so if
        // WinHTTP's own erratic cancellation (measured at 1490-4506ms for
        // this same 700ms budget) were doing the work instead of the
        // watchdog, roughly half the attempts would land above this bound and
        // say so, instead of quietly passing under a 4s ceiling.
        constexpr long long kCeilingMs = 2500;
        const bool gave_up = !response.ok() && ms < kCeilingMs;
        if (gave_up)
            ++timed_out;

        // Always printed, pass or fail: elapsed time and the backend's own
        // error string (which carries GetLastError on Windows) are the
        // evidence. requests_seen separates "the client never reached the
        // server" (0) from "the server read the request and the client then
        // waited it out" (1).
        std::fprintf(stderr,
                     "  [timeout-probe %d/%d] elapsed=%lldms ok=%d status=%ld "
                     "requests_seen=%d network_error='%s' -> %s\n",
                     i + 1, kProbes, ms, response.ok() ? 1 : 0, response.status,
                     server.requestCount(), response.network_error.c_str(),
                     gave_up ? "gave up (expected)" : "WAITED OUT THE STALL");

        ST_ASSERT(!response.ok());
        ST_ASSERT(ms < kCeilingMs);
    }
    std::fprintf(stderr, "  [timeout-probe] %d/%d attempts honoured the %ldms timeout\n",
                 timed_out, kProbes, kTimeoutMs);
}

} // namespace

int main()
{
    testNormalizeServerUrl();
    testUrlEncodeAndRedaction();
    testRedactSensitiveParams();
    testRequestShape();
    testSlotsHappyPath();
    testSlotsEdgeCases();
    testTokenHappyPath();
    testHttpErrorStatuses();
    testMalformedSuccessBodies();
    testNetworkErrorAndInvalidConfig();
    testPlatformBackendAgainstLoopback();
    testPlatformBackendTimeout();
    return st_test_report("api_client");
}