#include "network/license_status.h"
#include "db/db_keys.h"
#include <gtest/gtest.h>

#include <cstdlib>
#include <chrono>
#include <filesystem>
#include <string>
#include <thread>

using namespace radiantwave::license;
using namespace radiantwave::db;

namespace {

// A temporary database created fresh per test and cleaned up on exit.
struct TempDb {
    TempDb() {
        path = (std::filesystem::temp_directory_path() /
                ("test_rw_license_status_" + std::to_string(counter++) + ".db"))
                   .string();
        std::filesystem::remove(path);
        db.initialize(path);
    }

    ~TempDb() {
        db.close();
        std::filesystem::remove(path);
    }

    std::string path;
    DatabaseManager db;
    static int counter;
};

int TempDb::counter = 0;

std::string env(const char* name) {
    const char* value = std::getenv(name);
    return value ? std::string(value) : std::string();
}

// Waits until `status()` no longer reports Checking (or `timeout` elapses).
// Returns the final status.
Status waitForResult(LicenseStatusTracker& tracker, int timeoutMs = 2000) {
    const auto deadline = std::chrono::steady_clock::now() +
                          std::chrono::milliseconds(timeoutMs);
    while (tracker.status() == Status::Checking) {
        if (std::chrono::steady_clock::now() >= deadline) break;
        std::this_thread::sleep_for(std::chrono::milliseconds(10));
    }
    return tracker.status();
}

} // namespace

// ─── Pure mapping (offline) ─────────────────────────────────────────────

TEST(LicenseStatusTest, StatusForResultMapping) {
    EXPECT_EQ(statusForResult(Result::Ok), Status::Valid);
    EXPECT_EQ(statusForResult(Result::NotConfigured), Status::Invalid);
    EXPECT_EQ(statusForResult(Result::Invalid), Status::Invalid);
    EXPECT_EQ(statusForResult(Result::NetworkError), Status::Invalid);
}

long long epochSeconds(long long offsetSeconds = 0) {
    const auto now = std::chrono::system_clock::now();
    return std::chrono::duration_cast<std::chrono::seconds>(now.time_since_epoch())
               .count() +
           offsetSeconds;
}

TEST(LicenseStatusTest, StatusForResultWithGraceNoPriorValidation) {
    TempDb tmp;
    // No "last verified" stamp: a network error still invalidates because the
    // device has no record of ever confirming the license.
    EXPECT_EQ(statusForResultWithGrace(Result::Ok, tmp.db), Status::Valid);
    EXPECT_EQ(statusForResultWithGrace(Result::NotConfigured, tmp.db), Status::Invalid);
    EXPECT_EQ(statusForResultWithGrace(Result::Invalid, tmp.db), Status::Invalid);
    EXPECT_EQ(statusForResultWithGrace(Result::NetworkError, tmp.db), Status::Invalid);
}

TEST(LicenseStatusTest, StatusForResultWithGraceWithinWindow) {
    TempDb tmp;
    tmp.db.setKV(KV_LICENSE_LAST_VERIFIED, std::to_string(epochSeconds()));

    // A network error keeps a recently-confirmed license valid...
    EXPECT_EQ(statusForResultWithGrace(Result::NetworkError, tmp.db), Status::Valid);
    // ...but the grace period never rescues an explicit rejection.
    EXPECT_EQ(statusForResultWithGrace(Result::Invalid, tmp.db), Status::Invalid);
    EXPECT_EQ(statusForResultWithGrace(Result::NotConfigured, tmp.db), Status::Invalid);
}

TEST(LicenseStatusTest, StatusForResultWithGraceExpired) {
    TempDb tmp;
    tmp.db.setKV(KV_LICENSE_LAST_VERIFIED, std::to_string(epochSeconds(-8 * 24 * 3600)));
    EXPECT_EQ(statusForResultWithGrace(Result::NetworkError, tmp.db), Status::Invalid);
}

// ─── Scheduling policy (pure) ───────────────────────────────────────────

TEST(LicenseStatusPolicyTest, ForcedAlwaysRuns) {
    EXPECT_TRUE(shouldValidate(true, false, false, Status::Invalid, 1000, 999));
    EXPECT_TRUE(shouldValidate(true, false, false, Status::Unknown, 1000, 0));
}

TEST(LicenseStatusPolicyTest, CredentialChangeRuns) {
    EXPECT_TRUE(shouldValidate(false, true, false, Status::Invalid, 1000, 999));
}

TEST(LicenseStatusPolicyTest, OverdueRecheckRuns) {
    EXPECT_TRUE(shouldValidate(false, false, true, Status::Invalid, 1000, 999));
}

TEST(LicenseStatusPolicyTest, InvalidUnchangedDoesNotRun) {
    // An invalid license with unchanged credentials is never re-checked, no
    // matter how old the last attempt is.
    EXPECT_FALSE(shouldValidate(false, false, false, Status::Invalid, 1000, 999));
    EXPECT_FALSE(shouldValidate(false, false, false, Status::Invalid,
                                1000, 1000 - 10 * RECHECK_INTERVAL_SECONDS));
    EXPECT_FALSE(shouldValidate(false, false, false, Status::Unknown, 1000, 0));
}

TEST(LicenseStatusPolicyTest, ValidRechecksAfterInterval) {
    const long long now = 1000000;
    EXPECT_FALSE(shouldValidate(false, false, false, Status::Valid, now, now - 10));
    EXPECT_FALSE(shouldValidate(false, false, false, Status::Valid, now,
                                now - (RECHECK_INTERVAL_SECONDS - 1)));
    EXPECT_TRUE(shouldValidate(false, false, false, Status::Valid, now,
                               now - RECHECK_INTERVAL_SECONDS));
    // Off for several hours: still immediately due, not another full hour away.
    EXPECT_TRUE(shouldValidate(false, false, false, Status::Valid, now,
                               now - 5 * RECHECK_INTERVAL_SECONDS));
}

TEST(LicenseStatusPolicyTest, ValidWithMissingStampRechecks) {
    EXPECT_TRUE(shouldValidate(false, false, false, Status::Valid, 1000, 0));
}

// ─── Worker lifecycle (no network) ──────────────────────────────────────

TEST(LicenseStatusTest, UnknownBeforeStart) {
    LicenseStatusTracker tracker;
    EXPECT_EQ(tracker.status(), Status::Unknown);
    EXPECT_FALSE(tracker.isValid());

    // refresh() before start() must not spawn a worker.
    tracker.refresh();
    EXPECT_EQ(tracker.status(), Status::Unknown);
}

TEST(LicenseStatusTest, InvalidWhenNoCredentials) {
    TempDb tmp;
    LicenseStatusTracker tracker;
    tracker.start(tmp.db);
    tracker.refresh();

    // NotConfigured resolves without touching the network.
    EXPECT_EQ(waitForResult(tracker), Status::Invalid);
    EXPECT_FALSE(tracker.isValid());
    tracker.shutdown();
}

TEST(LicenseStatusTest, InvalidWhenDatabaseClosed) {
    TempDb tmp;
    LicenseStatusTracker tracker;
    tracker.start(tmp.db);
    tracker.refresh();
    EXPECT_EQ(waitForResult(tracker), Status::Invalid);
    tracker.shutdown();
}

TEST(LicenseStatusTest, LoadsPersistedValidWithinGraceWithoutChecking) {
    TempDb tmp;
    tmp.db.setKV(KV_LICENSE_KEY, "k");
    tmp.db.setKV(KV_EMAIL_ADDRESS, "e");
    tmp.db.setKV(KV_LICENSE_CHECKED_KEY, "k");
    tmp.db.setKV(KV_LICENSE_CHECKED_EMAIL, "e");
    tmp.db.setKV(KV_LICENSE_CHECK_STATUS, "valid");
    tmp.db.setKV(KV_LICENSE_LAST_VERIFIED, std::to_string(epochSeconds()));
    tmp.db.setKV(KV_LICENSE_LAST_CHECK, std::to_string(epochSeconds()));

    LicenseStatusTracker tracker;
    tracker.start(tmp.db);
    // Seeded valid + recently checked + unchanged credentials: the worker must
    // stay idle (no network), and the status is valid immediately.
    EXPECT_EQ(tracker.status(), Status::Valid);
    tracker.shutdown();
}

TEST(LicenseStatusTest, RecordResultUpdatesStatusAndPersistsCheckedPair) {
    TempDb tmp;
    const std::string key = "AAAA-BBBB-CCCC-DDDD";
    const std::string email = "user@example.com";
    tmp.db.setKV(KV_LICENSE_KEY, key);
    tmp.db.setKV(KV_EMAIL_ADDRESS, email);
    // Seed the checked pair as already-invalid so the worker does not start a
    // network check; this exercises recordResult() in isolation.
    tmp.db.setKV(KV_LICENSE_CHECKED_KEY, key);
    tmp.db.setKV(KV_LICENSE_CHECKED_EMAIL, email);
    tmp.db.setKV(KV_LICENSE_CHECK_STATUS, "invalid");

    LicenseStatusTracker tracker;
    tracker.start(tmp.db);
    EXPECT_EQ(tracker.status(), Status::Invalid);

    tracker.recordResult(Result::Ok);
    EXPECT_EQ(tracker.status(), Status::Valid);
    EXPECT_TRUE(tracker.isValid());
    EXPECT_EQ(tmp.db.getKV(KV_LICENSE_CHECKED_KEY), key);
    EXPECT_EQ(tmp.db.getKV(KV_LICENSE_CHECKED_EMAIL), email);
    EXPECT_EQ(tmp.db.getKV(KV_LICENSE_CHECK_STATUS), "valid");
    EXPECT_FALSE(tmp.db.getKV(KV_LICENSE_LAST_CHECK).empty());
    tracker.shutdown();
}

// ─── Live: confirmed-valid license (requires env credentials) ───────────

TEST(LicenseStatusLiveTest, ValidWhenLicensePairAccepted) {
    const std::string key = env("RW_LIVE_LICENSE_KEY");
    const std::string email = env("RW_LIVE_LICENSE_EMAIL");
    if (key.empty() || email.empty()) {
        GTEST_SKIP() << "RW_LIVE_LICENSE_KEY / RW_LIVE_LICENSE_EMAIL not set";
    }

    TempDb tmp;
    tmp.db.setKV(KV_LICENSE_KEY, key);
    tmp.db.setKV(KV_EMAIL_ADDRESS, email);

    LicenseStatusTracker tracker;
    tracker.start(tmp.db);
    tracker.refresh();

    EXPECT_EQ(waitForResult(tracker, 20000), Status::Valid);
    EXPECT_TRUE(tracker.isValid());
    tracker.shutdown();
}