/*
 * Copyright (C) 2017, The LineageOS Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

//#define LOG_NDEBUG 0
#define LOG_TAG "FingerprintWrapper"

#include <cutils/log.h>

#include <hardware/hardware.h>
#include <hardware/fingerprint.h>
#include <utils/threads.h>

typedef struct {
    fingerprint_device_t base;
    union {
        fingerprint_device_t *device;
        hw_device_t *hw_device;
    } vendor;
} device_t;

static android::Mutex vendor_mutex;

static union {
    const fingerprint_module_t *module;
    const hw_module_t *hw_module;
} vendor;

static bool try_hal(const char *class_name, const char *device_name)
{
    const hw_module_t *module;

    int rv = hw_get_module_by_class("fingerprint", class_name, &module);
    if (rv) {
        ALOGE("Failed to open fingerprint module: class %s, error %d", class_name, rv);
        vendor.module = NULL;
    } else {
        hw_device_t *device;

        ALOGI("loaded fingerprint module, class %s: %s version %x", class_name, module->name,
            module->module_api_version);
        if (module->methods->open(module, device_name, &device) == 0) {
             device->close(device);
             ALOGI("Successfully loaded the device for fingerprint module, class %s", class_name);
             vendor.hw_module = module;
        } else {
             ALOGE("Failed to open a device using fingerprint HAL, class %s", class_name);
        }
    }
    return vendor.module != NULL;
}

static bool ensure_vendor_module_is_loaded(const char *device_name)
{
    android::Mutex::Autolock lock(vendor_mutex);

    if (!vendor.module) {
        if (!try_hal("fpc", device_name)) {
            try_hal("goodix", device_name);
        }
    }

    return vendor.module != NULL;
}

static int set_notify(struct fingerprint_device *dev, fingerprint_notify_t notify)
{
    device_t *device = (device_t *) dev;

    return device->vendor.device->set_notify(device->vendor.device, notify);
}

static uint64_t pre_enroll(struct fingerprint_device *dev)
{
    device_t *device = (device_t *) dev;

    return device->vendor.device->pre_enroll(device->vendor.device);
}

static int enroll(struct fingerprint_device *dev, const hw_auth_token_t *hat, uint32_t gid,
                uint32_t timeout_sec)
{
    device_t *device = (device_t *) dev;

    return device->vendor.device->enroll(device->vendor.device, hat, gid, timeout_sec);
}

static int post_enroll(struct fingerprint_device *dev)
{
    device_t *device = (device_t *) dev;

    return device->vendor.device->post_enroll(device->vendor.device);
}

static uint64_t get_authenticator_id(struct fingerprint_device *dev)
{
    device_t *device = (device_t *) dev;

    return device->vendor.device->get_authenticator_id(device->vendor.device);
}

static int cancel(struct fingerprint_device *dev)
{
    device_t *device = (device_t *) dev;

    return device->vendor.device->cancel(device->vendor.device);
}

static int enumerate(struct fingerprint_device *dev)
{
    device_t *device = (device_t *) dev;

    return device->vendor.device->enumerate(device->vendor.device);
}

static int remove(struct fingerprint_device *dev, uint32_t gid, uint32_t fid)
{
    device_t *device = (device_t *) dev;

    return device->vendor.device->remove(device->vendor.device, gid, fid);
}

static int set_active_group(struct fingerprint_device *dev, uint32_t gid, const char *store_path)
{
    device_t *device = (device_t *) dev;

    return device->vendor.device->set_active_group(device->vendor.device, gid, store_path);
}

static int authenticate(struct fingerprint_device *dev, uint64_t operation_id, uint32_t gid)
{
    device_t *device = (device_t *) dev;

    return device->vendor.device->authenticate(device->vendor.device, operation_id, gid);
}

static int device_close(hw_device_t *hw_device)
{
    device_t *device = (device_t *) hw_device;
    int rv = device->base.common.close(device->vendor.hw_device);
    free(device);
    return rv;
}

static int device_open(const hw_module_t *module, const char *name, hw_device_t **device_out)
{
    int rv;
    device_t *device;

    if (!ensure_vendor_module_is_loaded(name)) {
        return -EINVAL;
    }

    device = (device_t *) calloc(sizeof(*device), 1);
    if (!device) {
        ALOGE("%s: Failed to allocate memory", __func__);
        return -ENOMEM;
    }

    rv = vendor.module->common.methods->open(vendor.hw_module, name, &device->vendor.hw_device);
    if (rv) {
        ALOGE("%s: failed to open, error %d\n", __func__, rv);
        free(device);
        return rv;
    }

    device->base.common.tag = HARDWARE_DEVICE_TAG;
    device->base.common.version = device->vendor.device->common.version;
    device->base.common.module = (hw_module_t *) module;
    device->base.common.close = device_close;

    device->base.set_notify = set_notify;
    device->base.pre_enroll = pre_enroll;
    device->base.enroll = enroll;
    device->base.post_enroll = post_enroll;
    device->base.get_authenticator_id = get_authenticator_id;
    device->base.cancel = cancel;
    device->base.enumerate = enumerate;
    device->base.remove = remove;
    device->base.set_active_group = set_active_group;
    device->base.authenticate = authenticate;

    *device_out = (hw_device_t *) device;
    return 0;
}

static struct hw_module_methods_t module_methods = {
    .open = device_open
};

fingerprint_module_t HAL_MODULE_INFO_SYM = {
    .common = {
        .tag = HARDWARE_MODULE_TAG,
        .module_api_version = FINGERPRINT_MODULE_API_VERSION_2_1,
        .hal_api_version = HARDWARE_HAL_API_VERSION,
        .id = FINGERPRINT_HARDWARE_MODULE_ID,
        .name = "Lineage Fingerprint Wrapper",
        .author = "The LineageOS Project",
        .methods = &module_methods,
        .dso = NULL, /* remove compilation warnings */
        .reserved = {0}, /* remove compilation warnings */
    },
};