// Ändert Optionen in Lumas Konfiguration (/luma/config.ini):
//   splash_position                   -> Boot-Splash "MBMNET aktiv" anzeigen
//   enable_external_firm_and_modules  -> nötig, damit Luma die Patches in /luma/sysmodules lädt
//   enable_game_patching              -> nötig, damit Luma Patches in /luma/titles lädt (Miiverse)
// Beim Zurücksetzen wird eine Option nur wieder ausgeschaltet, wenn MBMNET sie eingeschaltet hat
// (Merker in /3ds/mbmnet/...).
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <strings.h>
#include <sys/stat.h>

#include "lumaconfig.h"

#define CONFIG_FILE    "sdmc:/luma/config.ini"
#define SPLASH_MARKER  "sdmc:/3ds/mbmnet/splash-war-aus"
#define MODULES_MARKER "sdmc:/3ds/mbmnet/module-waren-aus"
#define PATCHING_MARKER "sdmc:/3ds/mbmnet/game-patching-war-aus"

// Setzt "key = value". Gibt den alten Wert in oldValue zurück. false, wenn Datei/Option fehlt.
static bool set_option(const char *key, const char *value, char *oldValue, size_t oldLen)
{
    FILE *f = fopen(CONFIG_FILE, "rb");
    if (!f) return false;
    fseek(f, 0, SEEK_END);
    long size = ftell(f);
    fseek(f, 0, SEEK_SET);
    if (size <= 0 || size > 64 * 1024) { fclose(f); return false; }
    char *in = malloc(size + 1);
    char *out = malloc(size + 128);
    bool ok = in && out && fread(in, 1, size, f) == (size_t)size;
    fclose(f);
    if (!ok) { free(in); free(out); return false; }
    in[size] = 0;

    size_t keyLen = strlen(key);
    bool found = false;
    size_t o = 0;
    for (char *line = in; *line;) {
        char *end = strchr(line, '\n');
        size_t len = end ? (size_t)(end - line + 1) : strlen(line);
        char *p = line;
        while (*p == ' ' || *p == '\t') p++;
        char *eq = strchr(p, '=');
        bool isKey = !found && strncmp(p, key, keyLen) == 0 && (p[keyLen] == ' ' || p[keyLen] == '=')
                     && eq && eq < line + len;
        if (isKey) {
            char *v = eq + 1;
            while (*v == ' ') v++;
            size_t vl = strcspn(v, "\r\n");
            snprintf(oldValue, oldLen, "%.*s", (int)vl, v);
            o += sprintf(out + o, "%s = %s%s", key, value, (end && end > line && end[-1] == '\r') ? "\r\n" : "\n");
            found = true;
        } else {
            memcpy(out + o, line, len);
            o += len;
        }
        line += len;
    }

    if (found && strcasecmp(oldValue, value) != 0) {
        f = fopen(CONFIG_FILE, "wb");
        ok = f && fwrite(out, 1, o, f) == o;
        if (f) fclose(f);
    }
    free(in);
    free(out);
    return found && ok;
}

static void touch(const char *path)
{
    FILE *m = fopen(path, "w");
    if (m) fclose(m);
}

static bool exists(const char *path)
{
    struct stat st;
    return stat(path, &st) == 0;
}

bool lumaconfig_enable_splash(void)
{
    char old[32] = "";
    if (!set_option("splash_position", "after payloads", old, sizeof(old))) return false;
    if (strcasecmp(old, "off") == 0) touch(SPLASH_MARKER);
    return true;
}

void lumaconfig_restore_splash(void)
{
    if (!exists(SPLASH_MARKER)) return;   // war schon vorher an: nichts ändern
    char old[32] = "";
    set_option("splash_position", "off", old, sizeof(old));
    remove(SPLASH_MARKER);
}

bool lumaconfig_enable_modules(void)
{
    char old[8] = "";
    if (!set_option("enable_external_firm_and_modules", "1", old, sizeof(old))) return false;
    if (strcmp(old, "0") == 0) touch(MODULES_MARKER);
    return true;
}

void lumaconfig_keep_modules(void)
{
    remove(MODULES_MARKER);
}

void lumaconfig_restore_modules(void)
{
    if (!exists(MODULES_MARKER)) return;
    char old[8] = "";
    set_option("enable_external_firm_and_modules", "0", old, sizeof(old));
    remove(MODULES_MARKER);
}

bool lumaconfig_enable_game_patching(void)
{
    char old[8] = "";
    if (!set_option("enable_game_patching", "1", old, sizeof(old))) return false;
    if (strcmp(old, "0") != 0) return false;   // war schon an
    touch(PATCHING_MARKER);
    return true;
}

void lumaconfig_restore_game_patching(void)
{
    if (!exists(PATCHING_MARKER)) return;
    char old[8] = "";
    set_option("enable_game_patching", "0", old, sizeof(old));
    remove(PATCHING_MARKER);
}