#include "gem/server.h"

#include <arpa/inet.h>
#include <errno.h>
#include <netinet/in.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/socket.h>
#include <unistd.h>

struct fixture { int generated; };

static int generate(void *opaque, const struct gem_chat_request *request,
                    gem_stream_emit_fn emit, void *user,
                    size_t *input_tokens, size_t *output_tokens,
                    const char **finish_reason, char *error, size_t error_size)
{
    struct fixture *fixture = opaque;
    if (!strstr(request->prompt, "<|turn>user\nhello<turn|>")) {
        (void)snprintf(error, error_size, "unexpected fixture prompt");
        return -1;
    }
    static const char answer[] = "native hax ok";
    struct gem_stream_event event = {
        .kind = GEM_STREAM_TEXT, .text = answer, .text_size = sizeof(answer) - 1,
    };
    if (emit(&event, user) != 0) return -1;
    *input_tokens = 4; *output_tokens = 3; *finish_reason = "stop";
    fixture->generated = 1;
    return 0;
}

int main(void)
{
    int listener = socket(AF_INET, SOCK_STREAM, 0);
    if (listener < 0) return 1;
    struct sockaddr_in address = {.sin_family = AF_INET};
    if (inet_pton(AF_INET, "127.0.0.1", &address.sin_addr) != 1 ||
        bind(listener, (struct sockaddr *)&address, sizeof(address)) != 0 ||
        listen(listener, 8) != 0) {
        close(listener); return 1;
    }
    socklen_t address_size = sizeof(address);
    if (getsockname(listener, (struct sockaddr *)&address, &address_size) != 0) {
        close(listener); return 1;
    }
    printf("%u\n", (unsigned)ntohs(address.sin_port));
    fflush(stdout);
    struct fixture fixture = {0};
    struct gem_server_config config = {
        .model_id = "gem-test", .context_length = 32768, .default_max_tokens = 32,
        .sampler = {.temperature = 0, .top_k = 1, .top_p = 1,
                    .repeat_penalty = 1, .repeat_last_n = 64, .seed = 1},
        .backend = &fixture, .generate = generate,
    };
    for (unsigned request = 0; request < 8 && !fixture.generated; ++request) {
        int client;
        do { client = accept(listener, NULL, NULL); } while (client < 0 && errno == EINTR);
        if (client < 0) { close(listener); return 1; }
        char error[256];
        (void)gem_server_handle_connection(client, &config, error, sizeof(error));
        close(client);
    }
    close(listener);
    return fixture.generated ? 0 : 1;
}