/*
 * Copyright 2007 The Android Open Source Project
 *
 * Input event device.
 */
#include "Common.h"

#include <stdlib.h>
#include <string.h>

#include <fcntl.h>
#include <sys/ioctl.h>
#include <linux/input.h>


/*
 * Input event device state.
 */
typedef struct EventState {
    struct input_id ident;

    char*   name;
    char*   location;
    char*   idstr;
    int     protoVersion;
} EventState;

/*
 * Key bit mask, for EVIOCGBIT(EV_KEY).
 *
 * (For now, just pretend to be a "goldfish" like the emulator.)
 */
static const unsigned char gKeyBitMask[64] = {
    0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 
    0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 
    0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 
    0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 
    0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 
    0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 
    0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 
    0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 
};

/*
 * Set some stuff up.
 */
static void configureInitialState(const char* pathName, EventState* eventState)
{
    /*
     * Swim like a goldfish.
     */
    eventState->ident.bustype = 0;
    eventState->ident.vendor = 0;
    eventState->ident.product = 0;
    eventState->ident.version = 0;

    eventState->name = strdup(gWrapSim.keyMap);
    eventState->location = strdup("");
    eventState->idstr = strdup("");
    eventState->protoVersion = 0x010000;
}

/*
 * Free up the state structure.
 */
static void freeState(EventState* eventState)
{
    if (eventState != NULL) {
        free(eventState->name);
        free(eventState->location);
        free(eventState->idstr);
        free(eventState);
    }
}

/*
 * Handle one of the EVIOCGABS requests.
 *
 * Currently not doing much here.
 */
static void handleAbsGet(int reqIdx, void* argp)
{
    struct input_absinfo info;

    switch (reqIdx) {
    case ABS_X:
        wsLog("  req for abs X\n");
        break;
    case ABS_Y:
        wsLog("  req for abs Y\n");
        break;
    case ABS_PRESSURE:
        wsLog("  req for abs PRESSURE\n");
        break;
    case ABS_TOOL_WIDTH:
        wsLog("  req for abs TOOL_WIDTH\n");
        break;
    default:
        wsLog("  req for unexpected event abs 0x%02x\n", reqIdx);
        break;
    }

    memset(&info, 0, sizeof(info));
    memcpy(argp, &info, sizeof(struct input_absinfo));
}

/*
 * Return the next available input event.
 *
 * We just pass this through to the real "read", since "fd" is real.
 */
static ssize_t readEvent(FakeDev* dev, int fd, void* buf, size_t count)
{
    return _ws_read(fd, buf, count);
}

/*
 * Somebody is trying to write to the event pipe.  This can be used to set
 * the state of LED.
 */
static ssize_t writeEvent(FakeDev* dev, int fd, const void* buf, size_t count)
{
    const struct input_event* piev;

    if (count == sizeof(*piev)) {
        piev = (const struct input_event*) buf;

        if (piev->type == EV_LED) {
            wsLog("%s: set LED code=%d value=%d\n",
                dev->debugName, piev->code, piev->value);
        } else {
            wsLog("%s: writeEvent got %d bytes, type=%d\n",
                dev->debugName, count, piev->type);
        }
    } else {
        wsLog("%s: warning: writeEvent got %d bytes, not sure why\n",
            dev->debugName, count);
    }

    return count;
}

/*
 * Handle event ioctls.
 */
static int ioctlEvent(FakeDev* dev, int fd, int request, void* argp)
{
    EventState* state = (EventState*) dev->state;
    unsigned int urequest = (unsigned int) request;

    wsLog("%s: ioctl(0x%x, %p)\n", dev->debugName, urequest, argp);

    if (_IOC_TYPE(urequest) != _IOC_TYPE(EVIOCGVERSION)) {
        wsLog("%s: inappropriate ioctl 0x%08x\n", dev->debugName, urequest);
        return -1;
    }

    if (urequest == EVIOCGVERSION) {
        *(int*)argp = state->protoVersion;
    } else if (urequest == EVIOCGID) {
        memcpy(argp, &state->ident, sizeof(struct input_id));
    } else if (_IOC_NR(urequest) == _IOC_NR(EVIOCGNAME(0))) {
        int maxLen = _IOC_SIZE(urequest);
        int strLen = (int) strlen(state->name);
        if (strLen >= maxLen) {
            errno = EINVAL;
            return -1;
        }
        memcpy(argp, state->name, strLen+1);
        return strLen;
    } else if (_IOC_NR(urequest) == _IOC_NR(EVIOCGPHYS(0))) {
        int maxLen = _IOC_SIZE(urequest);
        int strLen = (int) strlen(state->location);
        if (strLen >= maxLen) {
            errno = EINVAL;
            return -1;
        }
        memcpy(argp, state->location, strLen+1);
        return strLen;
    } else if (_IOC_NR(urequest) == _IOC_NR(EVIOCGUNIQ(0))) {
        /* device doesn't seem to support this, neither will we */
        return -1;
    } else if (_IOC_NR(urequest) == _IOC_NR(EVIOCGBIT(EV_KEY,0))) {
        /* keys */
        int maxLen = _IOC_SIZE(urequest);
        if (maxLen > (int) sizeof(gKeyBitMask))
            maxLen = sizeof(gKeyBitMask);
        memcpy(argp, gKeyBitMask, maxLen);
    } else if (_IOC_NR(urequest) == _IOC_NR(EVIOCGBIT(EV_REL,0))) {
        /* relative controllers (trackball) */
        int maxLen = _IOC_SIZE(urequest);
        memset(argp, 0xff, maxLen);
    } else if (!getenv("NOTOUCH") && _IOC_NR(urequest) == _IOC_NR(EVIOCGBIT(EV_ABS,0))) {
        // absolute controllers (touch screen)
        int maxLen = _IOC_SIZE(urequest);
        memset(argp, 0xff, maxLen);

    } else if (_IOC_NR(urequest) >= _IOC_NR(EVIOCGABS(ABS_X)) &&
               _IOC_NR(urequest) <= _IOC_NR(EVIOCGABS(ABS_MAX)))
    {
        /* get abs value / limits */
        int reqIdx = _IOC_NR(urequest) - _IOC_NR(EVIOCGABS(ABS_X));
        handleAbsGet(reqIdx, argp);
    } else {
        wsLog("GLITCH: UNKNOWN ioctl request 0x%x on %s\n",
            urequest, dev->debugName);
        return -1;
    }

    return 0;
}

/*
 * Free up our state before closing down the fake descriptor.
 */
static int closeEvent(FakeDev* dev, int fd)
{
    freeState((EventState*)dev->state);
    dev->state = NULL;
    if (gWrapSim.keyInputDevice == dev) {
        gWrapSim.keyInputDevice = NULL;
        wsLog("Sim input device closed\n");
    }
    return 0;
}

/*
 * Open an input event device.
 */
FakeDev* wsOpenDevEvent(const char* pathName, int flags)
{
    FakeDev* newDev = wsCreateRealFakeDev(pathName);
    if (newDev != NULL) {
        newDev->read = readEvent;
        newDev->write = writeEvent;
        newDev->ioctl = ioctlEvent;
        newDev->close = closeEvent;

        EventState* eventState = calloc(1, sizeof(EventState));

        configureInitialState(pathName, eventState);
        newDev->state = eventState;

        /*
         * First one opened becomes the place where we queue up input
         * events from the simulator.  This approach will fail if the
         * app opens the device, then opens it a second time for input,
         * then closes the first.  The app doesn't currently do this (though
         * it does do quick opens to fiddle with LEDs).
         */
        if (gWrapSim.keyInputDevice == NULL) {
            gWrapSim.keyInputDevice = newDev;
            wsLog("Device %p / %d will receive sim input events\n",
                newDev, newDev->fd);
        }
    }

    return newDev;
}

/*
 * Write a key event.
 */
static int sendKeyEvent(FakeDev* dev, int code, int isDown)
{
    struct input_event iev;
    ssize_t actual;

    gettimeofday(&iev.time, NULL);
    iev.type = EV_KEY;
    iev.code = code;
    iev.value = (isDown != 0) ? 1 : 0;

    actual = _ws_write(dev->otherFd, &iev, sizeof(iev));
    if (actual != (ssize_t) sizeof(iev)) {
        wsLog("WARNING: send key event partial write (%d of %d)\n",
            actual, sizeof(iev));
        return -1;
    }

    return 0;
}

/*
 * Write an absolute (touch screen) event.
 */
static int sendAbsButton(FakeDev* dev, int x, int y, int isDown)
{
    struct input_event iev;
    ssize_t actual;

    wsLog("absButton x=%d y=%d down=%d\n", x, y, isDown);

    gettimeofday(&iev.time, NULL);
    iev.type = EV_KEY;
    iev.code = BTN_TOUCH;
    iev.value = (isDown != 0) ? 1 : 0;

    actual = _ws_write(dev->otherFd, &iev, sizeof(iev));
    if (actual != (ssize_t) sizeof(iev)) {
        wsLog("WARNING: send touch event partial write (%d of %d)\n",
            actual, sizeof(iev));
        return -1;
    }

    return 0;
}

/*
 * Write an absolute (touch screen) event.
 */
static int sendAbsMovement(FakeDev* dev, int x, int y)
{
    struct input_event iev;
    ssize_t actual;

    wsLog("absMove x=%d y=%d\n", x, y);

    gettimeofday(&iev.time, NULL);
    iev.type = EV_ABS;
    iev.code = ABS_X;
    iev.value = x;

    actual = _ws_write(dev->otherFd, &iev, sizeof(iev));
    if (actual != (ssize_t) sizeof(iev)) {
        wsLog("WARNING: send abs movement event partial X write (%d of %d)\n",
            actual, sizeof(iev));
        return -1;
    }

    iev.code = ABS_Y;
    iev.value = y;

    actual = _ws_write(dev->otherFd, &iev, sizeof(iev));
    if (actual != (ssize_t) sizeof(iev)) {
        wsLog("WARNING: send abs movement event partial Y write (%d of %d)\n",
            actual, sizeof(iev));
        return -1;
    }

    return 0;
}

/*
 * Not quite sure what this is for, but the emulator does it.
 */
static int sendAbsSyn(FakeDev* dev)
{
    struct input_event iev;
    ssize_t actual;

    gettimeofday(&iev.time, NULL);
    iev.type = EV_SYN;
    iev.code = 0;
    iev.value = 0;

    actual = _ws_write(dev->otherFd, &iev, sizeof(iev));
    if (actual != (ssize_t) sizeof(iev)) {
        wsLog("WARNING: send abs movement syn (%d of %d)\n",
            actual, sizeof(iev));
        return -1;
    }

    return 0;
}

/*
 * Send a key event to the fake key event device.
 *
 * We have to translate the simulator key event into one or more device
 * key events.
 */
void wsSendSimKeyEvent(int key, int isDown)
{
    FakeDev* dev;
    EventState* state;

    dev = gWrapSim.keyInputDevice;
    if (dev == NULL)
        return;

    sendKeyEvent(dev, key, isDown);
}

/*
 * Send a touch-screen event to the fake key event device.
 *
 * We have to translate the simulator key event into one or more device
 * key events.
 */
void wsSendSimTouchEvent(int action, int x, int y)
{
    FakeDev* dev;
    EventState* state;

    dev = gWrapSim.keyInputDevice;
    if (dev == NULL)
        return;

    if (action == kTouchDown) {
        sendAbsMovement(dev, x, y);
        sendAbsButton(dev, x, y, 1);
        sendAbsSyn(dev);
    } else if (action == kTouchUp) {
        sendAbsButton(dev, x, y, 0);
        sendAbsSyn(dev);
    } else if (action == kTouchDrag) {
        sendAbsMovement(dev, x, y);
        sendAbsSyn(dev);
    } else {
        wsLog("WARNING: unexpected sim touch action  %d\n", action);
    }
}