#include "nocal/storage/sync_cache.hpp"
#include "nocal/sync/microsoft_account.hpp"
#include "nocal/sync/microsoft_graph.hpp"
#include "nocal/sync/oauth.hpp"
#include "nocal/sync/oauth_tokens.hpp"
#include "nocal/sync/secret_store.hpp"

#include <cstdint>
#include <cstdlib>
#include <exception>
#include <filesystem>
#include <functional>
#include <iostream>
#include <map>
#include <optional>
#include <span>
#include <stdexcept>
#include <string>
#include <string_view>
#include <vector>

namespace {

using nocal::storage::CachedAccount;
using nocal::storage::SyncCache;
using nocal::sync::AuthorizationCallback;
using nocal::sync::AuthorizationCallbackReceiver;
using nocal::sync::BrowserLauncher;
using nocal::sync::EntropySource;
using nocal::sync::HttpMethod;
using nocal::sync::HttpRequest;
using nocal::sync::HttpResponse;
using nocal::sync::HttpTransport;
using nocal::sync::MicrosoftAccountError;
using nocal::sync::OAuthClientConfig;
using nocal::sync::OAuthSecretStore;
using nocal::sync::OAuthTokens;

void require(bool condition, std::string_view message) {
    if (!condition) {
        throw std::runtime_error(std::string{message});
    }
}

// -----------------------------------------------------------------------
// TempDirectory for a real SyncCache
// -----------------------------------------------------------------------
class TempDirectory {
public:
    TempDirectory() {
        std::string pattern =
            (std::filesystem::temp_directory_path() / "nocal-microsoft-account-tests.XXXXXX")
                .string();
        std::vector<char> writable(pattern.begin(), pattern.end());
        writable.push_back('\0');
        const char* created = ::mkdtemp(writable.data());
        if (created == nullptr) {
            throw std::runtime_error("mkdtemp failed");
        }
        path_ = created;
    }

    TempDirectory(const TempDirectory&) = delete;
    TempDirectory& operator=(const TempDirectory&) = delete;

    ~TempDirectory() {
        std::error_code ignored;
        std::filesystem::remove_all(path_, ignored);
    }

    [[nodiscard]] const std::filesystem::path& path() const noexcept { return path_; }

private:
    std::filesystem::path path_;
};

// -----------------------------------------------------------------------
// ScriptedEntropy – fixed deterministic values
// -----------------------------------------------------------------------
class ScriptedEntropy final : public EntropySource {
public:
    explicit ScriptedEntropy(std::vector<std::array<std::byte, 32>> scripted_values)
        : values(std::move(scripted_values)) {}

    std::vector<std::array<std::byte, 32>> values;
    std::size_t calls{0};

    void fill(std::span<std::byte> output) override {
        require(output.size() == 32, "entropy request was not exactly 32 bytes");
        const std::size_t call = calls++;
        require(call < values.size(), "unexpected entropy request");
        std::copy(values[call].begin(), values[call].end(), output.begin());
    }
};

// -----------------------------------------------------------------------
// ScriptedBrowser
// -----------------------------------------------------------------------
class ScriptedBrowser final : public BrowserLauncher {
public:
    std::vector<std::string> urls;

    void open(const std::string& url) override { urls.push_back(url); }
};

// -----------------------------------------------------------------------
// ScriptedReceiver – copies state from browser URL if needed
// -----------------------------------------------------------------------
class ScriptedReceiver final : public AuthorizationCallbackReceiver {
public:
    std::string redirect{"http://127.0.0.1:43123/callback"};
    AuthorizationCallback callback;
    std::size_t receives{0};
    bool copy_browser_state{true};
    ScriptedBrowser* browser{nullptr};

    [[nodiscard]] std::string redirect_uri() const override { return redirect; }

    AuthorizationCallback receive() override {
        ++receives;
        if (copy_browser_state && browser != nullptr && !browser->urls.empty()) {
            // Extract state from the authorization URL
            const std::string& url = browser->urls.front();
            const std::size_t state_pos = url.find("state=");
            if (state_pos != std::string::npos) {
                const std::size_t value_start = state_pos + 6;
                const std::size_t amp = url.find('&', value_start);
                const std::size_t len = (amp == std::string::npos) ? url.size() - value_start
                                                                   : amp - value_start;
                AuthorizationCallback result = callback;
                result.state = url.substr(value_start, len);
                return result;
            }
        }
        return callback;
    }
};

// -----------------------------------------------------------------------
// ScriptedTransport – scripted responses for token exchange then /me
// -----------------------------------------------------------------------
class ScriptedTransport final : public HttpTransport {
public:
    struct ResponseSpec {
        int status{200};
        std::string body;
        bool throw_on_send{false};
        std::string send_error_message{};
    };

    std::vector<HttpRequest> requests;
    std::vector<ResponseSpec> responses;

    HttpResponse send(const HttpRequest& request) override {
        requests.push_back(request);
        const std::size_t index = requests.size() - 1;
        if (index >= responses.size()) {
            return {200, {}, "{}"};
        }
        const ResponseSpec& spec = responses[index];
        if (spec.throw_on_send) {
            throw std::runtime_error(spec.send_error_message);
        }
        return {spec.status, {}, spec.body};
    }
};

// -----------------------------------------------------------------------
// ScriptedSecretStore – in-memory with injectable store failure
// -----------------------------------------------------------------------
class ScriptedSecretStore final : public OAuthSecretStore {
public:
    std::map<std::string, OAuthTokens> store_data;
    bool throw_on_store{false};
    std::string store_error_message{};
    std::size_t store_calls{0};
    std::size_t load_calls{0};
    std::size_t erase_calls{0};

    void store(std::string account_id, const OAuthTokens& tokens, std::stop_token = {}) override {
        ++store_calls;
        if (throw_on_store) {
            throw std::runtime_error(store_error_message);
        }
        store_data[std::move(account_id)] = tokens;
    }

    [[nodiscard]] std::optional<OAuthTokens> load(
        std::string account_id, std::stop_token = {}) override {
        ++load_calls;
        const auto found = store_data.find(account_id);
        if (found != store_data.end()) {
            return found->second;
        }
        return std::nullopt;
    }

    void erase(std::string account_id, std::stop_token = {}) override {
        ++erase_calls;
        store_data.erase(account_id);
    }
};

// -----------------------------------------------------------------------
// Controllable clock
// -----------------------------------------------------------------------
class ControllableClock {
public:
    std::int64_t value{1000};

    [[nodiscard]] std::int64_t operator()() { return value; }
};

// -----------------------------------------------------------------------
// Helpers
// -----------------------------------------------------------------------

[[nodiscard]] std::array<std::byte, 32> zeros() { return {}; }

[[nodiscard]] std::string token_response_body(std::string_view access_token,
    std::string_view refresh_token, std::int64_t expires_in) {
    return "{\"access_token\":\"" + std::string(access_token)
        + "\",\"refresh_token\":\"" + std::string(refresh_token)
        + "\",\"token_type\":\"Bearer\",\"expires_in\":" + std::to_string(expires_in) + "}";
}

[[nodiscard]] std::string me_response_body(
    std::string_view id, std::string_view display_name, std::string_view user_principal_name) {
    std::string body = "{\"id\":\"" + std::string(id) + "\"";
    if (!display_name.empty()) {
        body += ",\"displayName\":\"" + std::string(display_name) + "\"";
    }
    if (!user_principal_name.empty()) {
        body += ",\"userPrincipalName\":\"" + std::string(user_principal_name) + "\"";
    }
    body += "}";
    return body;
}

// -----------------------------------------------------------------------
// Test: Happy path
// -----------------------------------------------------------------------
void test_happy_path() {
    TempDirectory temp;
    SyncCache cache(temp.path() / "cache.db");

    ScriptedEntropy entropy{{zeros(), zeros()}};
    ScriptedBrowser browser;
    ScriptedReceiver receiver;
    receiver.browser = &browser;
    receiver.callback = {"auth-code", "", "", ""};
    ScriptedTransport transport;
    transport.responses.push_back(
        {200, token_response_body("access-token-value", "refresh-token-value", 3600)});
    transport.responses.push_back(
        {200, me_response_body("remote-subject", "Display Name", "user@example.com")});
    ScriptedSecretStore secret_store;
    ControllableClock clock;

    OAuthClientConfig config;
    config.client_id = "test-client-id";
    config.authorization_endpoint = "https://login.example/auth";
    config.token_endpoint = "https://login.example/token";
    config.scopes = {"offline_access", "User.Read", "Calendars.Read"};

    const CachedAccount account = nocal::sync::connect_microsoft_account(
        config, browser, receiver, transport, entropy, secret_store, cache,
        [&clock]() { return clock(); });

    // Verify returned account
    require(account.provider == "microsoft-graph", "wrong provider");

    // Compute expected account id
    const std::string expected_id =
        nocal::sync::microsoft_account_id("remote-subject");
    require(account.id == expected_id, "account id mismatch");
    require(account.remote_subject == "remote-subject", "remote subject mismatch");
    require(account.display_name == "Display Name", "display name mismatch");

    // Cache snapshot has exactly one account
    const auto snapshot = cache.snapshot();
    require(snapshot.accounts.size() == 1, "expected exactly one cached account");
    require(snapshot.accounts.front() == account, "cached account differs from returned");

    // Secret store holds the parsed tokens under the same id
    const auto stored_tokens = secret_store.store_data.find(expected_id);
    require(stored_tokens != secret_store.store_data.end(), "tokens not stored");
    require(stored_tokens->second.access_token == "access-token-value",
        "wrong stored access token");
    require(stored_tokens->second.refresh_token == "refresh-token-value",
        "wrong stored refresh token");
    require(stored_tokens->second.token_type == "Bearer", "wrong stored token type");

    // Exactly one browser URL, one token request, one /me GET with Bearer token
    require(browser.urls.size() == 1, "expected exactly one browser URL");
    require(transport.requests.size() == 2, "expected exactly two HTTP requests");
    require(transport.requests[0].method == HttpMethod::post,
        "first request was not POST (token)");
    require(transport.requests[0].url == "https://login.example/token",
        "first request URL mismatch");
    require(transport.requests[1].method == HttpMethod::get,
        "second request was not GET (/me)");
    require(transport.requests[1].url.find("graph.microsoft.com") != std::string::npos,
        "second request URL does not contain graph.microsoft.com");
    bool has_bearer = false;
    for (const auto& header : transport.requests[1].headers) {
        if (header.name == "Authorization") {
            has_bearer = header.value.find("Bearer access-token-value") != std::string::npos;
        }
    }
    require(has_bearer, "/me request did not carry Bearer token");
}

// -----------------------------------------------------------------------
// Test: Idempotent reconnect
// -----------------------------------------------------------------------
void test_idempotent_reconnect() {
    TempDirectory temp;
    SyncCache cache(temp.path() / "cache.db");

    auto do_connect = [&]() -> std::string {
        ScriptedEntropy entropy{{zeros(), zeros()}};
        ScriptedBrowser browser;
        ScriptedReceiver receiver;
        receiver.browser = &browser;
        receiver.callback = {"auth-code", "", "", ""};
        ScriptedTransport transport;
        transport.responses.push_back(
            {200, token_response_body("access-token-" + std::to_string(transport.requests.size()),
                 "refresh-token-" + std::to_string(transport.requests.size()), 3600)});
        transport.responses.push_back(
            {200, me_response_body("same-subject", "Same User", "same@example.com")});
        ScriptedSecretStore secret_store;
        ControllableClock clock;

        OAuthClientConfig config;
        config.client_id = "test-client-id";
        config.authorization_endpoint = "https://login.example/auth";
        config.token_endpoint = "https://login.example/token";
        config.scopes = {"offline_access", "User.Read", "Calendars.Read"};

        const CachedAccount account = nocal::sync::connect_microsoft_account(
            config, browser, receiver, transport, entropy, secret_store, cache,
            [&clock]() { return clock(); });
        return account.id;
    };

    const std::string first_id = do_connect();
    const std::string second_id = do_connect();

    // Same account id
    require(first_id == second_id, "reconnect produced different account id");

    // Cache still has exactly one account
    const auto snapshot = cache.snapshot();
    require(snapshot.accounts.size() == 1, "expected exactly one account after reconnect");
    require(snapshot.accounts.front().id == first_id, "account id mismatch in cache");
}

// -----------------------------------------------------------------------
// Test: Authorization rejected
// -----------------------------------------------------------------------
void test_authorization_rejected() {
    TempDirectory temp;
    SyncCache cache(temp.path() / "cache.db");

    ScriptedEntropy entropy{{zeros(), zeros()}};
    ScriptedBrowser browser;
    ScriptedReceiver receiver;
    receiver.browser = &browser;
    receiver.callback = {"", "", "access_denied", ""};
    ScriptedTransport transport;
    ScriptedSecretStore secret_store;
    ControllableClock clock;

    OAuthClientConfig config;
    config.client_id = "test-client-id";
    config.authorization_endpoint = "https://login.example/auth";
    config.token_endpoint = "https://login.example/token";
    config.scopes = {"offline_access", "User.Read", "Calendars.Read"};

    bool caught = false;
    try {
        (void)nocal::sync::connect_microsoft_account(
            config, browser, receiver, transport, entropy, secret_store, cache,
            [&clock]() { return clock(); });
    } catch (const MicrosoftAccountError& e) {
        caught = true;
        require(std::string(e.what()) == "Microsoft authorization failed",
            "wrong error message on authorization rejection");
    } catch (const std::exception& e) {
        throw std::runtime_error(
            std::string("wrong exception type: ") + e.what());
    }
    require(caught, "expected MicrosoftAccountError");

    // Cache and secret store both untouched
    require(cache.snapshot().accounts.empty(), "cache was modified on authorization rejection");
    require(secret_store.store_calls == 0, "secret store was called on authorization rejection");
}

// -----------------------------------------------------------------------
// Test: Token endpoint returns non-2xx
// -----------------------------------------------------------------------
void test_token_endpoint_non2xx() {
    TempDirectory temp;
    SyncCache cache(temp.path() / "cache.db");

    ScriptedEntropy entropy{{zeros(), zeros()}};
    ScriptedBrowser browser;
    ScriptedReceiver receiver;
    receiver.browser = &browser;
    receiver.callback = {"auth-code", "", "", ""};
    ScriptedTransport transport;
    transport.responses.push_back({400, "{\"error\":\"invalid_grant\"}"});
    ScriptedSecretStore secret_store;
    ControllableClock clock;

    OAuthClientConfig config;
    config.client_id = "test-client-id";
    config.authorization_endpoint = "https://login.example/auth";
    config.token_endpoint = "https://login.example/token";
    config.scopes = {"offline_access", "User.Read", "Calendars.Read"};

    bool caught = false;
    try {
        (void)nocal::sync::connect_microsoft_account(
            config, browser, receiver, transport, entropy, secret_store, cache,
            [&clock]() { return clock(); });
    } catch (const MicrosoftAccountError& e) {
        caught = true;
        require(std::string(e.what()) == "Microsoft authorization failed",
            "wrong error message on token rejection");
    }
    require(caught, "expected MicrosoftAccountError");

    // Nothing stored
    require(cache.snapshot().accounts.empty(), "cache was modified on token error");
    require(secret_store.store_calls == 0, "secret store was called on token error");
}

// -----------------------------------------------------------------------
// Test: Token response missing refresh_token
// -----------------------------------------------------------------------
void test_token_response_missing_refresh() {
    TempDirectory temp;
    SyncCache cache(temp.path() / "cache.db");

    ScriptedEntropy entropy{{zeros(), zeros()}};
    ScriptedBrowser browser;
    ScriptedReceiver receiver;
    receiver.browser = &browser;
    receiver.callback = {"auth-code", "", "", ""};
    ScriptedTransport transport;
    // No refresh_token in response — parse_oauth_token_response will reject
    transport.responses.push_back(
        {200, "{\"access_token\":\"acc\",\"token_type\":\"Bearer\",\"expires_in\":3600}"});
    ScriptedSecretStore secret_store;
    ControllableClock clock;

    OAuthClientConfig config;
    config.client_id = "test-client-id";
    config.authorization_endpoint = "https://login.example/auth";
    config.token_endpoint = "https://login.example/token";
    config.scopes = {"offline_access", "User.Read", "Calendars.Read"};

    bool caught = false;
    try {
        (void)nocal::sync::connect_microsoft_account(
            config, browser, receiver, transport, entropy, secret_store, cache,
            [&clock]() { return clock(); });
    } catch (const MicrosoftAccountError& e) {
        caught = true;
        require(std::string(e.what()) == "Microsoft token response invalid",
            "wrong error message on missing refresh token");
    }
    require(caught, "expected MicrosoftAccountError");

    // Nothing stored
    require(cache.snapshot().accounts.empty(), "cache was modified on parse error");
    require(secret_store.store_calls == 0, "secret store was called on parse error");
}

// -----------------------------------------------------------------------
// Test: /me failure
// -----------------------------------------------------------------------
void test_me_failure() {
    TempDirectory temp;
    SyncCache cache(temp.path() / "cache.db");

    ScriptedEntropy entropy{{zeros(), zeros()}};
    ScriptedBrowser browser;
    ScriptedReceiver receiver;
    receiver.browser = &browser;
    receiver.callback = {"auth-code", "", "", ""};
    ScriptedTransport transport;
    // Successful token response
    transport.responses.push_back(
        {200, token_response_body("acc-token", "ref-token", 3600)});
    // /me returns garbage (malformed JSON)
    transport.responses.push_back({200, "not-valid-json"});
    ScriptedSecretStore secret_store;
    ControllableClock clock;

    OAuthClientConfig config;
    config.client_id = "test-client-id";
    config.authorization_endpoint = "https://login.example/auth";
    config.token_endpoint = "https://login.example/token";
    config.scopes = {"offline_access", "User.Read", "Calendars.Read"};

    bool caught = false;
    try {
        (void)nocal::sync::connect_microsoft_account(
            config, browser, receiver, transport, entropy, secret_store, cache,
            [&clock]() { return clock(); });
    } catch (const MicrosoftAccountError& e) {
        caught = true;
        require(std::string(e.what()) == "Microsoft identity read failed",
            "wrong error message on /me failure");
    }
    require(caught, "expected MicrosoftAccountError");

    // Cache and secret store untouched
    require(cache.snapshot().accounts.empty(), "cache was modified on /me failure");
    require(secret_store.store_calls == 0, "secret store was called on /me failure");
}

// -----------------------------------------------------------------------
// Test: Secret-store store() failure — cache retains the account row
// -----------------------------------------------------------------------
void test_secret_store_failure() {
    TempDirectory temp;
    SyncCache cache(temp.path() / "cache.db");

    ScriptedEntropy entropy{{zeros(), zeros()}};
    ScriptedBrowser browser;
    ScriptedReceiver receiver;
    receiver.browser = &browser;
    receiver.callback = {"auth-code", "", "", ""};
    ScriptedTransport transport;
    transport.responses.push_back(
        {200, token_response_body("acc-token", "ref-token", 3600)});
    transport.responses.push_back(
        {200, me_response_body("remote-subject", "Display Name", "user@example.com")});
    ScriptedSecretStore secret_store;
    secret_store.throw_on_store = true;
    secret_store.store_error_message = "secret service unavailable";
    ControllableClock clock;

    OAuthClientConfig config;
    config.client_id = "test-client-id";
    config.authorization_endpoint = "https://login.example/auth";
    config.token_endpoint = "https://login.example/token";
    config.scopes = {"offline_access", "User.Read", "Calendars.Read"};

    bool caught = false;
    try {
        (void)nocal::sync::connect_microsoft_account(
            config, browser, receiver, transport, entropy, secret_store, cache,
            [&clock]() { return clock(); });
    } catch (const MicrosoftAccountError& e) {
        caught = true;
        require(std::string(e.what()) == "credential storage failed",
            "wrong error message on store failure");
    }
    require(caught, "expected MicrosoftAccountError");

    // Cache DOES retain the account row (documented disconnected state)
    const auto snapshot = cache.snapshot();
    require(snapshot.accounts.size() == 1,
        "cache should retain the account row even when secret store fails");
    require(snapshot.accounts.front().remote_subject == "remote-subject",
        "cached account has wrong remote subject");

    // Verify secret store does NOT have the credentials
    const std::string expected_id =
        nocal::sync::microsoft_account_id("remote-subject");
    const auto stored = secret_store.store_data.find(expected_id);
    require(stored == secret_store.store_data.end(),
        "secret store should not contain credentials after store failure");
    require(secret_store.store_calls == 1, "store should have been attempted once");

    // A subsequent successful connect should complete (idempotent)
    ScriptedEntropy entropy2{{zeros(), zeros()}};
    ScriptedBrowser browser2;
    ScriptedReceiver receiver2;
    receiver2.browser = &browser2;
    receiver2.callback = {"auth-code-2", "", "", ""};
    ScriptedTransport transport2;
    transport2.responses.push_back(
        {200, token_response_body("acc-token-2", "ref-token-2", 3600)});
    transport2.responses.push_back(
        {200, me_response_body("remote-subject", "Display Name", "user@example.com")});
    ScriptedSecretStore secret_store2;
    ControllableClock clock2;

    const CachedAccount retry_account = nocal::sync::connect_microsoft_account(
        config, browser2, receiver2, transport2, entropy2, secret_store2, cache,
        [&clock2]() { return clock2(); });
    require(retry_account.id == expected_id,
        "retry account id should match deterministic id");
    require(cache.snapshot().accounts.size() == 1,
        "cache should still have exactly one account after successful retry");

    const auto stored2 = secret_store2.store_data.find(expected_id);
    require(stored2 != secret_store2.store_data.end(),
        "credentials should be stored after successful retry");
}

// -----------------------------------------------------------------------
// Test: Empty displayName falls back to userPrincipalName
// -----------------------------------------------------------------------
void test_empty_display_name_fallback() {
    TempDirectory temp;
    SyncCache cache(temp.path() / "cache.db");

    ScriptedEntropy entropy{{zeros(), zeros()}};
    ScriptedBrowser browser;
    ScriptedReceiver receiver;
    receiver.browser = &browser;
    receiver.callback = {"auth-code", "", "", ""};
    ScriptedTransport transport;
    transport.responses.push_back(
        {200, token_response_body("acc-token", "ref-token", 3600)});
    // No displayName in /me response
    transport.responses.push_back(
        {200, me_response_body("remote-subject", "", "fallback@example.com")});
    ScriptedSecretStore secret_store;
    ControllableClock clock;

    OAuthClientConfig config;
    config.client_id = "test-client-id";
    config.authorization_endpoint = "https://login.example/auth";
    config.token_endpoint = "https://login.example/token";
    config.scopes = {"offline_access", "User.Read", "Calendars.Read"};

    const CachedAccount account = nocal::sync::connect_microsoft_account(
        config, browser, receiver, transport, entropy, secret_store, cache,
        [&clock]() { return clock(); });

    require(account.display_name == "fallback@example.com",
        "display name should fall back to userPrincipalName");
}

// -----------------------------------------------------------------------
// Test: default_microsoft_client_id with env unset and set
// -----------------------------------------------------------------------
void test_default_client_id() {
    // Save original env state and unset
    const char* original = std::getenv("NOCAL_MICROSOFT_CLIENT_ID");

    // Test with env unset
    if (original != nullptr) {
        ::unsetenv("NOCAL_MICROSOFT_CLIENT_ID");
    }
    const std::string unset_result = nocal::sync::default_microsoft_client_id();
    require(unset_result == nocal::sync::microsoft_client_id_placeholder,
        "default client id should be placeholder when env is unset");

    // Test with env set
    ::setenv("NOCAL_MICROSOFT_CLIENT_ID", "my-test-client-id", 1);
    const std::string set_result = nocal::sync::default_microsoft_client_id();
    require(set_result == "my-test-client-id",
        "default client id should match env when set");

    // Restore original
    if (original != nullptr) {
        ::setenv("NOCAL_MICROSOFT_CLIENT_ID", original, 1);
    } else {
        ::unsetenv("NOCAL_MICROSOFT_CLIENT_ID");
    }
}

// -----------------------------------------------------------------------
// Test: microsoft_oauth_config
// -----------------------------------------------------------------------
void test_microsoft_oauth_config() {
    const OAuthClientConfig config = nocal::sync::microsoft_oauth_config("my-client-id");

    require(config.client_id == "my-client-id", "client_id mismatch");
    require(config.authorization_endpoint
            == "https://login.microsoftonline.com/common/oauth2/v2.0/authorize",
        "wrong authorization endpoint");
    require(config.token_endpoint
            == "https://login.microsoftonline.com/common/oauth2/v2.0/token",
        "wrong token endpoint");

    require(config.scopes.size() == 3, "expected exactly 3 scopes");
    require(config.scopes[0] == "offline_access", "scope[0] mismatch");
    require(config.scopes[1] == "User.Read", "scope[1] mismatch");
    require(config.scopes[2] == "Calendars.Read", "scope[2] mismatch");
}

// -----------------------------------------------------------------------
// Test: Error messages never contain credential material
// -----------------------------------------------------------------------
void test_error_message_redaction() {
    TempDirectory temp;
    SyncCache cache(temp.path() / "cache.db");

    const std::string access_marker = "ACCESS_CRED_MARKER_12345";
    const std::string refresh_marker = "REFRESH_CRED_MARKER_67890";
    const std::string auth_code_marker = "AUTH_CODE_MARKER_ABCDE";

    // Test 1: Token endpoint error (400)
    {
        ScriptedEntropy entropy{{zeros(), zeros()}};
        ScriptedBrowser browser;
        ScriptedReceiver receiver;
        receiver.browser = &browser;
        receiver.callback = {auth_code_marker, "", "", ""};
        ScriptedTransport transport;
        transport.responses.push_back({400, access_marker + refresh_marker});
        ScriptedSecretStore secret_store;
        ControllableClock clock;

        OAuthClientConfig config;
        config.client_id = "test-client-id";
        config.authorization_endpoint = "https://login.example/auth";
        config.token_endpoint = "https://login.example/token";
        config.scopes = {"offline_access", "User.Read", "Calendars.Read"};

        try {
            (void)nocal::sync::connect_microsoft_account(
                config, browser, receiver, transport, entropy, secret_store, cache,
                [&clock]() { return clock(); });
        } catch (const std::exception& e) {
            const std::string msg = e.what();
            require(msg.find(access_marker) == std::string::npos,
                "error leaked access token on 400");
            require(msg.find(refresh_marker) == std::string::npos,
                "error leaked refresh token on 400");
            require(msg.find(auth_code_marker) == std::string::npos,
                "error leaked auth code on 400");
        }
    }

    // Test 2: Parse error (missing refresh_token)
    {
        ScriptedEntropy entropy{{zeros(), zeros()}};
        ScriptedBrowser browser;
        ScriptedReceiver receiver;
        receiver.browser = &browser;
        receiver.callback = {auth_code_marker, "", "", ""};
        ScriptedTransport transport;
        transport.responses.push_back(
            {200, "{\"access_token\":\"" + access_marker
                      + "\",\"token_type\":\"Bearer\",\"expires_in\":3600}"});
        ScriptedSecretStore secret_store;
        ControllableClock clock;

        OAuthClientConfig config;
        config.client_id = "test-client-id";
        config.authorization_endpoint = "https://login.example/auth";
        config.token_endpoint = "https://login.example/token";
        config.scopes = {"offline_access", "User.Read", "Calendars.Read"};

        try {
            (void)nocal::sync::connect_microsoft_account(
                config, browser, receiver, transport, entropy, secret_store, cache,
                [&clock]() { return clock(); });
        } catch (const std::exception& e) {
            const std::string msg = e.what();
            require(msg.find(access_marker) == std::string::npos,
                "error leaked access token on parse failure");
            require(msg.find(auth_code_marker) == std::string::npos,
                "error leaked auth code on parse failure");
        }
    }

    // Test 3: /me failure
    {
        ScriptedEntropy entropy{{zeros(), zeros()}};
        ScriptedBrowser browser;
        ScriptedReceiver receiver;
        receiver.browser = &browser;
        receiver.callback = {auth_code_marker, "", "", ""};
        ScriptedTransport transport;
        transport.responses.push_back(
            {200, "{\"access_token\":\"" + access_marker
                      + "\",\"refresh_token\":\"" + refresh_marker
                      + "\",\"token_type\":\"Bearer\",\"expires_in\":3600}"});
        transport.responses.push_back(
            {200, "{\"bad_field\":" + access_marker + "}"});
        ScriptedSecretStore secret_store;
        ControllableClock clock;

        OAuthClientConfig config;
        config.client_id = "test-client-id";
        config.authorization_endpoint = "https://login.example/auth";
        config.token_endpoint = "https://login.example/token";
        config.scopes = {"offline_access", "User.Read", "Calendars.Read"};

        try {
            (void)nocal::sync::connect_microsoft_account(
                config, browser, receiver, transport, entropy, secret_store, cache,
                [&clock]() { return clock(); });
        } catch (const std::exception& e) {
            const std::string msg = e.what();
            require(msg.find(access_marker) == std::string::npos,
                "error leaked access token on /me failure");
            require(msg.find(refresh_marker) == std::string::npos,
                "error leaked refresh token on /me failure");
            require(msg.find(auth_code_marker) == std::string::npos,
                "error leaked auth code on /me failure");
        }
    }

    // Test 4: Secret store failure
    {
        ScriptedEntropy entropy{{zeros(), zeros()}};
        ScriptedBrowser browser;
        ScriptedReceiver receiver;
        receiver.browser = &browser;
        receiver.callback = {auth_code_marker, "", "", ""};
        ScriptedTransport transport;
        transport.responses.push_back(
            {200, "{\"access_token\":\"" + access_marker
                      + "\",\"refresh_token\":\"" + refresh_marker
                      + "\",\"token_type\":\"Bearer\",\"expires_in\":3600}"});
        transport.responses.push_back(
            {200, me_response_body("remote-subject", "Display", "user@example.com")});
        ScriptedSecretStore secret_store;
        secret_store.throw_on_store = true;
        ControllableClock clock;

        OAuthClientConfig config;
        config.client_id = "test-client-id";
        config.authorization_endpoint = "https://login.example/auth";
        config.token_endpoint = "https://login.example/token";
        config.scopes = {"offline_access", "User.Read", "Calendars.Read"};

        try {
            (void)nocal::sync::connect_microsoft_account(
                config, browser, receiver, transport, entropy, secret_store, cache,
                [&clock]() { return clock(); });
        } catch (const std::exception& e) {
            const std::string msg = e.what();
            require(msg.find(access_marker) == std::string::npos,
                "error leaked access token on store failure");
            require(msg.find(refresh_marker) == std::string::npos,
                "error leaked refresh token on store failure");
            require(msg.find(auth_code_marker) == std::string::npos,
                "error leaked auth code on store failure");
        }
    }
}

// -----------------------------------------------------------------------
// Test: microsoft_account_id is deterministic
// -----------------------------------------------------------------------
void test_microsoft_account_id_deterministic() {
    const std::string first = nocal::sync::microsoft_account_id("user@example.com");
    const std::string second = nocal::sync::microsoft_account_id("user@example.com");
    require(
        first == second, "microsoft_account_id is not deterministic for same input");

    const std::string different =
        nocal::sync::microsoft_account_id("other@example.com");
    require(first != different,
        "microsoft_account_id should differ for different remote subjects");
}

} // namespace

int main() {
    try {
        test_happy_path();
        test_idempotent_reconnect();
        test_authorization_rejected();
        test_token_endpoint_non2xx();
        test_token_response_missing_refresh();
        test_me_failure();
        test_secret_store_failure();
        test_empty_display_name_fallback();
        test_default_client_id();
        test_microsoft_oauth_config();
        test_error_message_redaction();
        test_microsoft_account_id_deterministic();
    } catch (const std::exception& error) {
        std::cerr << "microsoft account tests failed: " << error.what() << '\n';
        return 1;
    }
    std::cout << "microsoft account tests passed\n";
    return 0;
}