// Copyright 2018 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include <fs-management/ram-nand.h>

#include <fcntl.h>
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>

#include <fbl/auto_call.h>
#include <fbl/string_buffer.h>
#include <fbl/unique_fd.h>
#include <lib/fzl/fdio.h>
#include <lib/fdio/util.h>
#include <zircon/device/device.h>
#include <zircon/types.h>
#include <zircon/nand/c/fidl.h>

#include <utility>

namespace {

constexpr char kBasePath[] = "/dev/misc/nand-ctl";

} // namespace

namespace fs_mgmt {

zx_status_t RamNandCtl::Create(fbl::RefPtr<RamNandCtl>* out) {
    devmgr_launcher::Args args;
    args.sys_device_driver = devmgr_integration_test::IsolatedDevmgr::kSysdevDriver;
    args.load_drivers.push_back(devmgr_integration_test::IsolatedDevmgr::kSysdevDriver);
    args.driver_search_paths.push_back("/boot/driver");

    fbl::unique_ptr<devmgr_integration_test::IsolatedDevmgr> devmgr;
    zx_status_t st = devmgr_integration_test::IsolatedDevmgr::Create(std::move(args), &devmgr);
    if (st != ZX_OK) {
        fprintf(stderr, "Could not create ram_nand_ctl device, %d\n", st);
        return st;
    }

    fbl::unique_fd ctl;
    st = devmgr_integration_test::RecursiveWaitForFile(devmgr->devfs_root(), "misc/nand-ctl",
                                                       zx::deadline_after(zx::sec(5)), &ctl);
    if (st != ZX_OK) {
        fprintf(stderr, "ram_nand_ctl device failed enumerated, %d\n", st);
        return st;
    }

    *out = fbl::AdoptRef(new RamNandCtl(std::move(devmgr), std::move(ctl)));
    return ZX_OK;
}

zx_status_t RamNand::Create(const zircon_nand_RamNandInfo* config, std::optional<RamNand>* out) {
    fbl::unique_fd control(open(kBasePath, O_RDWR));

    zx::channel ctl_svc;
    zx_status_t st = fdio_get_service_handle(control.release(),
                                             ctl_svc.reset_and_get_address());

    char name[zircon_nand_NAME_LEN + 1];
    size_t out_name_size;
    zx_status_t status;
    st = zircon_nand_RamNandCtlCreateDevice(ctl_svc.get(), config, &status, name,
                                            zircon_nand_NAME_LEN, &out_name_size);
    if (st != ZX_OK || status != ZX_OK) {
        st = st != ZX_OK ? st : status;
        fprintf(stderr, "Could not create ram_nand device, %d\n", st);
        return st;
    }
    name[out_name_size] = '\0';
    fbl::StringBuffer<PATH_MAX> path;
    path.Append(kBasePath);
    path.Append("/");
    path.Append(name);

    fbl::unique_fd ram_nand(open(path.c_str(), O_RDWR));
    if (!ram_nand) {
        fprintf(stderr, "Could not open ram_nand\n");
        return ZX_ERR_INTERNAL;
    }

    *out = RamNand(std::move(ram_nand), path.ToString());
    return ZX_OK;
}

zx_status_t RamNand::Create(fbl::RefPtr<RamNandCtl> ctl, const zircon_nand_RamNandInfo* config,
                            std::optional<RamNand>* out) {

    fdio_t* io = fdio_unsafe_fd_to_io(ctl->fd().get());
    if (io == NULL) {
        fprintf(stderr, "Could not get fdio object\n");
        return ZX_ERR_INTERNAL;
    }
    zx_handle_t ctl_svc = fdio_unsafe_borrow_channel(io);

    char name[zircon_nand_NAME_LEN + 1];
    size_t out_name_size;
    zx_status_t status;
    zx_status_t st = zircon_nand_RamNandCtlCreateDevice(ctl_svc, config, &status, name,
                                                        zircon_nand_NAME_LEN, &out_name_size);
    fdio_unsafe_release(io);
    if (st != ZX_OK || status != ZX_OK) {
        st = st != ZX_OK ? st : status;
        fprintf(stderr, "Could not create ram_nand device, %d\n", st);
        return st;
    }
    name[out_name_size] = '\0';

    // TODO(ZX-3193): We should be able to open relative to ctl->fd(), but
    // due to a bug, we have to be relative to devfs_root instead.
    fbl::StringBuffer<PATH_MAX> path;
    path.Append("misc/nand-ctl/");
    path.Append(name);
    fprintf(stderr, "Trying to open (%s)\n", path.c_str());

    // TODO(ZX-3192): We should use RecursiveWaitForFile here but it doesn't seem to
    // work, so we sleep instead.
    sleep(1);
    fbl::unique_fd fd(openat(ctl->devfs_root().get(), path.c_str(), O_RDWR));
    if (!fd) {
        fprintf(stderr, "Could not open ram_nand\n");
        return ZX_ERR_IO;
    }

    *out = RamNand(std::move(fd), std::move(ctl));
    return ZX_OK;
}

zx_status_t RamNand::CreateIsolated(const zircon_nand_RamNandInfo* config,
                                    std::optional<RamNand>* out) {
    fbl::RefPtr<RamNandCtl> ctl;
    zx_status_t st = RamNandCtl::Create(&ctl);
    if (st != ZX_OK) {
        return st;
    }
    return Create(std::move(ctl), config, out);
}

RamNand::~RamNand() {
    if (unbind && fd_) {
      zx_status_t status = static_cast<zx_status_t>(ioctl_device_unbind(fd_.get()));
      if (status != ZX_OK) {
          fprintf(stderr, "Could not unbind ram_nand, %d\n", status);
      }
    }
}

} // namespace fs_mgmt