/*
 * Copyright (c) 2018 Atmosphère-NX
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms and conditions of the GNU General Public License,
 * version 2, as published by the Free Software Foundation.
 *
 * This program is distributed in the hope it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
#include <switch.h>
#include <string.h>
#include <vector>
#include <algorithm>

#include "ldr_registration.hpp"
#include "ldr_content_management.hpp"

static FsFileSystem g_CodeFileSystem = {0};

static std::vector<u64> g_created_titles;
static bool g_has_initialized_fs_dev = false;

Result ContentManagement::MountCode(u64 tid, FsStorageId sid) {
    char path[FS_MAX_PATH] = {0};
    Result rc;
    
    /* We defer SD card mounting, so if relevant ensure it is mounted. */
    if (!g_has_initialized_fs_dev) {   
        TryMountSdCard();
    }
    
    if (kernelAbove200() && g_has_initialized_fs_dev && R_SUCCEEDED(MountCodeNspOnSd(tid))) {
        return 0x0;
    }

        
    if (R_FAILED(rc = ResolveContentPath(path, tid, sid))) {
        return rc;
    }
    
    /* Fix up path. */
    for (unsigned int i = 0; i < FS_MAX_PATH && path[i] != '\x00'; i++) {
        if (path[i] == '\\') {
            path[i] = '/';
        }
    }
    
    /* Always re-initialize fsp-ldr, in case it's closed */
    if (R_FAILED(rc = fsldrInitialize())) {
        return rc;
    }
    
    if (R_FAILED(rc = fsldrOpenCodeFileSystem(tid, path, &g_CodeFileSystem))) {
        fsldrExit();
        return rc;
    }
    
    fsdevMountDevice("code", g_CodeFileSystem);
    
    fsldrExit();
    return rc;
}

Result ContentManagement::UnmountCode() {
    fsdevUnmountDevice("code");
    return 0;
}

Result ContentManagement::MountCodeNspOnSd(u64 tid) {
    char path[FS_MAX_PATH+1] = {0};
    snprintf(path, FS_MAX_PATH, "@Sdcard:/atmosphere/titles/%016lx/exefs.nsp", tid); 
    Result rc = fsOpenFileSystemWithId(&g_CodeFileSystem, 0, FsFileSystemType_ApplicationPackage, path);
    
    if (R_SUCCEEDED(rc)) {   
        fsdevMountDevice("code", g_CodeFileSystem);
    }
    
    return rc;
}

Result ContentManagement::MountCodeForTidSid(Registration::TidSid *tid_sid) {
    return MountCode(tid_sid->title_id, tid_sid->storage_id);
}

Result ContentManagement::ResolveContentPath(char *out_path, u64 tid, FsStorageId sid) {
    Result rc;
    LrRegisteredLocationResolver reg;
    LrLocationResolver lr;
    char path[FS_MAX_PATH] = {0};
    
    /* Try to get the path from the registered resolver. */
    if (R_FAILED(rc = lrOpenRegisteredLocationResolver(&reg))) {
        return rc;
    }
    
    if (R_SUCCEEDED(rc = lrRegLrResolveProgramPath(&reg, tid, path))) {
        strncpy(out_path, path, FS_MAX_PATH);
    } else if (rc != 0x408) {
        return rc;
    }
    
    serviceClose(&reg.s);
    if (R_SUCCEEDED(rc)) {
        return rc;
    }
    
    /* If getting the path from the registered resolver fails, fall back to the normal resolver. */
    if (R_FAILED(rc = lrOpenLocationResolver(sid, &lr))) {
        return rc;
    }
    
    if (R_SUCCEEDED(rc = lrLrResolveProgramPath(&lr, tid, path))) {
        strncpy(out_path, path, FS_MAX_PATH);
    }
    
    serviceClose(&lr.s);
    
    return rc;
}

Result ContentManagement::ResolveContentPathForTidSid(char *out_path, Registration::TidSid *tid_sid) {
    return ResolveContentPath(out_path, tid_sid->title_id, tid_sid->storage_id);
}

Result ContentManagement::RedirectContentPath(const char *path, u64 tid, FsStorageId sid) {
    Result rc;
    LrLocationResolver lr;
    
    if (R_FAILED(rc = lrOpenLocationResolver(sid, &lr))) {
        return rc;
    }
    
    rc = lrLrRedirectProgramPath(&lr, tid, path);
    
    serviceClose(&lr.s);
    
    return rc;
}

Result ContentManagement::RedirectContentPathForTidSid(const char *path, Registration::TidSid *tid_sid) {
    return RedirectContentPath(path, tid_sid->title_id, tid_sid->storage_id);
}

bool ContentManagement::HasCreatedTitle(u64 tid) {
    return std::find(g_created_titles.begin(), g_created_titles.end(), tid) != g_created_titles.end();
}

void ContentManagement::SetCreatedTitle(u64 tid) {
    if (!HasCreatedTitle(tid)) {
        g_created_titles.push_back(tid);
    }
}

void ContentManagement::TryMountSdCard() {
    /* Mount SD card, if psc, bus, and pcv have been created. */
    if (!g_has_initialized_fs_dev && HasCreatedTitle(0x0100000000000021) && HasCreatedTitle(0x010000000000000A) && HasCreatedTitle(0x010000000000001A)) {
        Handle tmp_hnd = 0;
        static const char * const required_active_services[] = {"pcv", "gpio", "pinmux", "psc:c"};
        for (unsigned int i = 0; i < sizeof(required_active_services) / sizeof(required_active_services[0]); i++) {
            if (R_FAILED(smGetServiceOriginal(&tmp_hnd, smEncodeName(required_active_services[i])))) {
                return;
            } else {
                svcCloseHandle(tmp_hnd);   
            }
        }
        
        if (R_SUCCEEDED(fsdevMountSdmc())) {
            g_has_initialized_fs_dev = true;
        }
    }
}