// HTTP über den Systemdienst http:C. Alles läuft über den MBMNET-Server (einfaches HTTP),
// der Katalog, Symbole und Downloads von Universal-DB und GitHub holt.
#include <3ds.h>
#include <stdlib.h>
#include <string.h>

#include "net.h"

#define CHUNK (128 * 1024)

static Result open_request(httpcContext *ctx, const char *url, u32 *status)
{
    Result rc = httpcOpenContext(ctx, HTTPC_METHOD_GET, url, 1);
    if (R_FAILED(rc)) return rc;
    httpcAddRequestHeaderField(ctx, "User-Agent", "MBMNET-Shop/" APP_VERSION);
    httpcSetKeepAlive(ctx, HTTPC_KEEPALIVE_DISABLED);
    if (R_SUCCEEDED(rc = httpcBeginRequest(ctx)))
        rc = httpcGetResponseStatusCodeTimeout(ctx, status, 30ULL * 1000 * 1000 * 1000);
    if (R_FAILED(rc)) httpcCloseContext(ctx);
    return rc;
}

u32 net_stream(const char *url, NetSink sink, void *ctx, Result *rcOut)
{
    httpcContext http;
    u32 status = 0, total = 0, got;
    Result rc = open_request(&http, url, &status);
    if (rcOut) *rcOut = rc;
    if (R_FAILED(rc)) return 0;
    if (status != 200) { httpcCloseContext(&http); return status; }

    httpcGetDownloadSizeState(&http, NULL, &total);
    u8 *buf = malloc(CHUNK);
    if (!buf) { httpcCloseContext(&http); if (rcOut) *rcOut = -2; return 0; }
    do {
        got = 0;
        rc = httpcDownloadData(&http, buf, CHUNK, &got);
        if (got && !sink(ctx, buf, got, total)) { rc = -3; break; }   // -3 = Empfänger hat abgebrochen
    } while (rc == (Result)HTTPC_RESULTCODE_DOWNLOADPENDING);
    free(buf);
    httpcCloseContext(&http);
    if (rcOut) *rcOut = rc;
    return R_SUCCEEDED(rc) ? 200 : 0;
}

typedef struct { u8 *data; u32 size, cap, max; } MemSink;

static bool to_memory(void *p, const u8 *data, u32 len, u32 total)
{
    MemSink *m = p;
    if (m->size + len > m->max) return false;
    if (m->size + len > m->cap) {
        u32 cap = m->cap ? m->cap : (total && total <= m->max ? total : 64 * 1024);
        while (cap < m->size + len) cap *= 2;
        u8 *bigger = realloc(m->data, cap);
        if (!bigger) return false;
        m->data = bigger;
        m->cap = cap;
    }
    memcpy(m->data + m->size, data, len);
    m->size += len;
    return true;
}

u32 net_get(const char *url, u8 **out, u32 *size, u32 max, Result *rc)
{
    MemSink m = { NULL, 0, 0, max };
    u32 status = net_stream(url, to_memory, &m, rc);
    if (status != 200) { free(m.data); m.data = NULL; m.size = 0; }
    *out = m.data;
    *size = m.size;
    return status;
}