/*
 * Logitech Unifying receiver emulation (HID++ 2.0 features).
 *
 * Copyright (c) 2014 Peter Wu <peter@lekensteyn.nl>
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */
#include "hw/hw.h"
#include "ui/console.h"
#include "hw/usb.h"
#include "dump.h"
#include "hw/input/hid.h"
#include "hw/usb/hid-logitech-dj.h"

/* hd - subject device; msg - input/output msg; fn - Function ID; params -
 * function parameters (in/out).
 * If the return value is negative, an error report must be returned. If 0, then
 * no output report must be generated. Higher values signify the number of
 * parameters that must not be cleared when outputting a response */
typedef int (*hidpp_feature_cb_t)(LHidDevice *hd, Hidpp20Msg *msg,
                                  uint8_t fn, uint8_t *params);
struct HidppFeature {
    uint16_t id;
#define HIDPP20_FEAT_TYPE_OBSOLETE  (1 << 7)
#define HIDPP20_FEAT_TYPE_HIDDEN    (1 << 6)
#define HIDPP20_FEAT_TYPE_INTERNAL  (1 << 5)
    uint8_t type;
    hidpp_feature_cb_t callback;
};

/* define a HID++ 2.0 feature with given name */
#define HIDPP20_FEATURE(name) \
    int name(LHidDevice *hd, Hidpp20Msg *msg, uint8_t fn, uint8_t *params)

static HIDPP20_FEATURE(feat_iroot)
{
    uint16_t feature_id;
    unsigned i;
    const HidppFeature *feat;

    switch (fn) {
    case 0: /* featureIndex, featureType = GetFeature(featureID) */
        feature_id = (params[0] << 8) | params[1];
        params[0] = params[1] = 0;
        for (i = 0; i < hd->info.features_count; i++) {
            feat = &hd->info.features[i];
            if (feat->id == feature_id) {
                params[0] = i + 1;
                params[1] = feat->type;
            }
        }
        return 2;
    case 1: /* ping = GetFeature(pingData) or version = GetProtocolVersion() */
        params[0] = hd->info.protocol_version >> 8;
        params[1] = (uint8_t) hd->info.protocol_version;
        // params[2] is not changed, that's the pingData
        return 3;
    default:
        return -HIDPP20_ERR_CODE_INVALID_FUNCTION_ID;
    }
}

static HIDPP20_FEATURE(feat_featureset)
{
    const HidppFeature *feat;

    switch (fn) {
    case 0: /* GetCount */
        params[0] = hd->info.features_count;
        return 1;
    case 1: /* featureID, featureType = GetFeatureId(featureIndex) */
        if (params[0] > hd->info.features_count) {
            return -HIDPP20_ERR_CODE_OUTOFRANGE;
        }
        feat = &hd->info.features[params[0]];
        params[0] = feat->id >> 8;
        params[1] = (uint8_t) feat->id;
        params[2] = feat->type;
        return 3;
    default:
        return -HIDPP20_ERR_CODE_INVALID_FUNCTION_ID;
    }
}

/* root feature not included! */
static const HidppFeature features_m525[] = {
    { 0x0001, 0, feat_featureset            },
};

void hidpp20_init_features(LHidDevice *hd) {
    switch (hd->info.wireless_pid) {
    case 0x4013:
        hd->info.features = features_m525;
        hd->info.features_count = ARRAY_SIZE(features_m525);
        break;
    }
}

int hidpp20_feature_call(LHidDevice *hd, Hidpp20Msg *func)
{
    uint8_t fn = func->func >> 4;
    const HidppFeature *feat;
    int r;

    if (func->feat_index > hd->info.features_count) {
        return -HIDPP20_ERR_CODE_INVALID_FEATURE_INDEX;
    }

    assert(hd->info.features != NULL);

    if (func->feat_index == 0) { /* IRoot (dual HID++ 1.0 and HID++ 2.0) */
        r = feat_iroot(hd, func, fn, func->params);
    } else { /* other features */
        feat = &hd->info.features[func->feat_index - 1];
        r = feat->callback(hd, func, fn, func->params);
    }
    if (r > 0) {
        // r are the parameters that must be kept, the others are cleared.
        assert(r <= sizeof(func->params));
        memset(func->params + r, 0, sizeof(func->params) - r);
    }

    return r;
}