// SPDX-License-Identifier: MIT
//
// Mocks the clawdforge HTTP API with cpp-httplib and exercises the SDK end to
// end. Each TEST_CASE spins up a fresh server bound to 127.0.0.1:0 (random
// free port) so cases can run in parallel without colliding.

#define DOCTEST_CONFIG_IMPLEMENT_WITH_MAIN
#include <doctest/doctest.h>

#include <atomic>
#include <chrono>
#include <cstdio>
#include <filesystem>
#include <fstream>
#include <future>
#include <memory>
#include <string>
#include <thread>

#include <httplib.h>
#include <nlohmann/json.hpp>

#include <clawdforge/client.hpp>

namespace cf = clawdforge;
using nlohmann::json;

namespace {

/// Owns a httplib::Server bound to 127.0.0.1:0 in a background thread. RAII —
/// the destructor stops the server and joins the thread.
class MockServer {
public:
    explicit MockServer(std::function<void(httplib::Server&)> wire_routes) {
        // Cap the worker thread pool low — cpp-httplib defaults to one worker
        // per CPU core, which on big hosts piles up under ASan and trips the
        // per-process map limit. Two workers is plenty for these tests.
        srv_.new_task_queue = [] { return new httplib::ThreadPool(2); };

        wire_routes(srv_);
        port_ = srv_.bind_to_any_port("127.0.0.1");
        REQUIRE(port_ > 0);
        thread_ = std::thread([this] { srv_.listen_after_bind(); });
        // Wait for the server to be ready (cheap poll — `listen_after_bind`
        // doesn't expose a barrier).
        for (int i = 0; i < 200; ++i) {
            if (srv_.is_running()) break;
            std::this_thread::sleep_for(std::chrono::milliseconds(5));
        }
        REQUIRE(srv_.is_running());
    }

    ~MockServer() {
        srv_.stop();
        if (thread_.joinable()) thread_.join();
    }

    [[nodiscard]] std::string base_url() const {
        return "http://127.0.0.1:" + std::to_string(port_);
    }

private:
    httplib::Server srv_;
    int port_{0};
    std::thread thread_;
};

[[nodiscard]] std::string write_temp_file(std::string_view content) {
    namespace fs = std::filesystem;
    const auto path = fs::temp_directory_path() /
                      ("clawdforge-test-" +
                       std::to_string(std::chrono::steady_clock::now().time_since_epoch().count()) +
                       ".bin");
    std::ofstream out(path, std::ios::binary);
    out.write(content.data(), static_cast<std::streamsize>(content.size()));
    out.close();
    return path.string();
}

}  // namespace

TEST_CASE("healthz returns parsed body") {
    MockServer mock{[](httplib::Server& s) {
        s.Get("/healthz", [](const httplib::Request&, httplib::Response& res) {
            res.set_content(
                R"({"ok":true,"claude_present":true,"claude_version":"1.2.3"})",
                "application/json");
        });
    }};

    cf::Client c{cf::ClientOptions{.base_url = mock.base_url(), .token = "cf_test"}};
    const auto h = c.healthz();
    CHECK(h.ok);
    CHECK(h.claude_present);
    CHECK(h.claude_version == "1.2.3");
}

TEST_CASE("run with JSON result decodes into variant<json>") {
    MockServer mock{[](httplib::Server& s) {
        s.Post("/run", [](const httplib::Request& req, httplib::Response& res) {
            CHECK(req.has_header("Authorization"));
            CHECK(req.get_header_value("Authorization") == "Bearer cf_test");
            const auto body = json::parse(req.body);
            CHECK(body.at("prompt").get<std::string>() == "hi");
            CHECK(body.at("model").get<std::string>() == "sonnet");
            res.set_content(
                R"({"ok":true,"result":{"hello":"world"},"duration_ms":42,"stop_reason":"end_turn"})",
                "application/json");
        });
    }};

    cf::Client c{cf::ClientOptions{.base_url = mock.base_url(), .token = "cf_test"}};
    const auto r = c.run(cf::RunRequest{.prompt = "hi", .model = "sonnet"});
    CHECK(r.ok);
    CHECK(r.duration_ms == 42);
    REQUIRE(r.stop_reason.has_value());
    CHECK(*r.stop_reason == "end_turn");
    const auto* j = std::get_if<nlohmann::json>(&r.result);
    REQUIRE(j != nullptr);
    CHECK(j->at("hello").get<std::string>() == "world");
}

TEST_CASE("run with string result decodes into variant<string>") {
    MockServer mock{[](httplib::Server& s) {
        s.Post("/run", [](const httplib::Request&, httplib::Response& res) {
            res.set_content(
                R"({"ok":true,"result":"plain text reply","duration_ms":12})",
                "application/json");
        });
    }};

    cf::Client c{cf::ClientOptions{.base_url = mock.base_url(), .token = "cf_test"}};
    const auto r = c.run(cf::RunRequest{.prompt = "hi"});
    const auto* s = std::get_if<std::string>(&r.result);
    REQUIRE(s != nullptr);
    CHECK(*s == "plain text reply");
}

TEST_CASE("run failure -> APIError with status 502 and body") {
    MockServer mock{[](httplib::Server& s) {
        s.Post("/run", [](const httplib::Request&, httplib::Response& res) {
            res.status = 502;
            res.set_content(
                R"({"ok":false,"error":"timeout","duration_ms":60000,"stderr":"...","stop_reason":null})",
                "application/json");
        });
    }};

    cf::Client c{cf::ClientOptions{.base_url = mock.base_url(), .token = "cf_test"}};
    try {
        (void)c.run(cf::RunRequest{.prompt = "hi"});
        FAIL("expected APIError");
    } catch (const cf::APIError& e) {
        CHECK(e.status_code() == 502);
        const auto body = json::parse(e.body());
        CHECK(body.at("error").get<std::string>() == "timeout");
    }
}

TEST_CASE("401 -> AuthError") {
    MockServer mock{[](httplib::Server& s) {
        s.Post("/run", [](const httplib::Request&, httplib::Response& res) {
            res.status = 401;
            res.set_content(R"({"detail":"bad token"})", "application/json");
        });
    }};
    cf::Client c{cf::ClientOptions{.base_url = mock.base_url(), .token = "cf_bad"}};
    CHECK_THROWS_AS(c.run(cf::RunRequest{.prompt = "hi"}), cf::AuthError);
}

TEST_CASE("run with files attaches list to body") {
    MockServer mock{[](httplib::Server& s) {
        s.Post("/run", [](const httplib::Request& req, httplib::Response& res) {
            const auto body = json::parse(req.body);
            REQUIRE(body.contains("files"));
            REQUIRE(body.at("files").is_array());
            CHECK(body.at("files").size() == 1);
            CHECK(body.at("files")[0].get<std::string>() == "ff_abcd");
            res.set_content(
                R"({"ok":true,"result":"got file","duration_ms":1})",
                "application/json");
        });
    }};

    cf::Client c{cf::ClientOptions{.base_url = mock.base_url(), .token = "cf_test"}};
    const auto r = c.run(cf::RunRequest{
        .prompt = "extract", .files = {"ff_abcd"}, .timeout_secs = 30});
    CHECK(r.ok);
}

TEST_CASE("upload_file streams a multipart and parses FileToken") {
    const std::string payload(1024 * 200, 'x');  // 200 KB
    const auto path = write_temp_file(payload);

    std::atomic<bool> saw_field{false};
    std::atomic<std::size_t> received_size{0};
    std::atomic<bool> saw_ttl{false};

    MockServer mock{[&](httplib::Server& s) {
        s.Post("/files", [&](const httplib::Request& req, httplib::Response& res) {
            if (req.has_file("file")) {
                saw_field = true;
                received_size = req.get_file_value("file").content.size();
            }
            if (req.has_file("ttl_secs")) {
                saw_ttl = true;
                CHECK(req.get_file_value("ttl_secs").content == "120");
            }
            res.set_content(
                R"({"file_token":"ff_xyz","ttl_secs":120,"size":204800})",
                "application/json");
        });
    }};

    cf::Client c{cf::ClientOptions{.base_url = mock.base_url(), .token = "cf_test"}};
    const auto ft = c.upload_file(path, 120);
    CHECK(ft.file_token == "ff_xyz");
    CHECK(ft.ttl_secs == 120);
    CHECK(ft.size == 204800);
    CHECK(saw_field.load());
    CHECK(saw_ttl.load());
    CHECK(received_size.load() == payload.size());

    std::filesystem::remove(path);
}

TEST_CASE("admin token CRUD round-trip") {
    std::vector<std::string> seen_methods;
    std::vector<std::string> seen_paths;

    MockServer mock{[&](httplib::Server& s) {
        s.Post("/admin/tokens", [&](const httplib::Request& req, httplib::Response& res) {
            seen_methods.emplace_back("POST");
            seen_paths.emplace_back("/admin/tokens");
            CHECK(req.get_header_value("Authorization") == "Bearer admin_secret");
            const auto body = json::parse(req.body);
            CHECK(body.at("name").get<std::string>() == "consumer-1");
            res.set_content(
                R"({"name":"consumer-1","token":"cf_NEWTOKEN","ip_cidrs":["10.0.0.0/8"]})",
                "application/json");
        });
        s.Get("/admin/tokens", [&](const httplib::Request& req, httplib::Response& res) {
            seen_methods.emplace_back("GET");
            seen_paths.emplace_back("/admin/tokens");
            CHECK(req.get_header_value("Authorization") == "Bearer admin_secret");
            res.set_content(
                R"({"tokens":[
                    {"name":"consumer-1","ip_cidrs":["10.0.0.0/8"],"created_at":1700000000,"extra":"yo"}
                ]})",
                "application/json");
        });
        s.Delete(R"(/admin/tokens/(.+))",
                 [&](const httplib::Request& req, httplib::Response& res) {
                     seen_methods.emplace_back("DELETE");
                     seen_paths.emplace_back(req.path);
                     res.set_content(R"({"ok":true})", "application/json");
                 });
    }};

    cf::Client c{cf::ClientOptions{.base_url = mock.base_url(),
                                   .token = "cf_test",
                                   .admin_token = "admin_secret"}};

    const auto created = c.create_token(cf::TokenCreateRequest{
        .name = "consumer-1", .ip_cidrs = {"10.0.0.0/8"}});
    CHECK(created.token == "cf_NEWTOKEN");

    const auto list = c.list_tokens();
    REQUIRE(list.size() == 1);
    CHECK(list[0].name == "consumer-1");
    REQUIRE(list[0].created_at.has_value());
    CHECK(*list[0].created_at == 1700000000);
    CHECK(list[0].extra.contains("extra"));

    c.revoke_token("consumer-1");

    REQUIRE(seen_methods.size() == 3);
    CHECK(seen_methods[0] == "POST");
    CHECK(seen_methods[1] == "GET");
    CHECK(seen_methods[2] == "DELETE");
    CHECK(seen_paths[2] == "/admin/tokens/consumer-1");
}

TEST_CASE("revoke_token without admin token throws AuthError") {
    cf::Client c{cf::ClientOptions{.base_url = "http://127.0.0.1:1", .token = "cf_test"}};
    CHECK_THROWS_AS(c.revoke_token("foo"), cf::AuthError);
}

TEST_CASE("transport-level failure surfaces as TransportError") {
    // Port 1 is reserved (tcpmux); connect should refuse fast on Linux.
    cf::Client c{cf::ClientOptions{
        .base_url = "http://127.0.0.1:1",
        .token = "cf_test",
        .timeout = std::chrono::seconds{2},
        .connect_timeout = std::chrono::seconds{1},
    }};
    auto fire = [&] {
        auto h = c.healthz();
        (void)h;
    };
    CHECK_THROWS_AS(fire(), cf::TransportError);
}

TEST_CASE("base_url is normalized (trailing slash trimmed)") {
    MockServer mock{[](httplib::Server& s) {
        s.Get("/healthz", [](const httplib::Request&, httplib::Response& res) {
            res.set_content(R"({"ok":true,"claude_present":false})", "application/json");
        });
    }};
    cf::Client c{cf::ClientOptions{.base_url = mock.base_url() + "/", .token = "cf_test"}};
    CHECK(c.base_url() == mock.base_url());
    const auto h = c.healthz();
    CHECK(h.ok);
    CHECK_FALSE(h.claude_present);
    CHECK(h.claude_version.empty());
}

TEST_CASE("invalid base_url scheme is rejected at construction") {
    auto make_ftp = [] {
        cf::ClientOptions opts;
        opts.base_url = "ftp://nope";
        opts.token = "x";
        cf::Client c{std::move(opts)};
        (void)c;
    };
    auto make_empty = [] {
        cf::ClientOptions opts;
        opts.base_url = "";
        opts.token = "x";
        cf::Client c{std::move(opts)};
        (void)c;
    };
    CHECK_THROWS_AS(make_ftp(), cf::ProtocolError);
    CHECK_THROWS_AS(make_empty(), cf::ProtocolError);
}