/*
 * Copyright (c) 2017, The Linux Foundation. All rights reserved.
 * Copyright (C) 2018 The LineageOS Project
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 * *    * Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above
 *       copyright notice, this list of conditions and the following
 *       disclaimer in the documentation and/or other materials provided
 *       with the distribution.
 *     * Neither the name of The Linux Foundation nor the names of its
 *       contributors may be used to endorse or promote products derived
 *       from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
 * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
 * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
 * IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#define LOG_NIDEBUG 0

#include <errno.h>
#include <time.h>
#include <string.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <dlfcn.h>
#include <stdlib.h>

#define LOG_TAG "QCOM PowerHAL"
#include <log/log.h>
#include <hardware/hardware.h>
#include <hardware/power.h>

#include "utils.h"
#include "metadata-defs.h"
#include "hint-data.h"
#include "performance.h"
#include "power-common.h"

#define NUM_PERF_MODES  3

#define SYS_DISPLAY_PWR "/sys/kernel/hbtp/display_pwr"

const int kMaxLaunchDuration = 5000; /* ms */
const int kMaxInteractiveDuration = 5000; /* ms */
const int kMinInteractiveDuration = 100; /* ms */

static int display_fd;

typedef enum {
    NORMAL_MODE       = 0,
    SUSTAINED_MODE    = 1,
    VR_MODE           = 2,
    VR_SUSTAINED_MODE = (SUSTAINED_MODE|VR_MODE),
    INVALID_MODE      = 0xFF
} perf_mode_type_t;

typedef struct perf_mode {
    perf_mode_type_t type;
    int perf_hint_id;
} perf_mode_t;

perf_mode_t perf_modes[NUM_PERF_MODES] = {
    { SUSTAINED_MODE, SUSTAINED_PERF_HINT },
    { VR_MODE, VR_MODE_HINT },
    { VR_SUSTAINED_MODE, VR_MODE_SUSTAINED_PERF_HINT }
};

static int current_mode = NORMAL_MODE;

static inline int get_perfd_hint_id(perf_mode_type_t type) {
    int i;
    for (i = 0; i < NUM_PERF_MODES; i++) {
        if (perf_modes[i].type == type) {
            ALOGD("Hint id is 0x%x for mode 0x%x", perf_modes[i].perf_hint_id, type);
            return perf_modes[i].perf_hint_id;
        }
    }
    ALOGD("Couldn't find the hint for mode 0x%x", type);
    return 0;
}

static int switch_mode(perf_mode_type_t mode) {
    int hint_id = 0;
    static int perfd_mode_handle = -1;

    // release existing mode if any
    if (CHECK_HANDLE(perfd_mode_handle)) {
        ALOGD("Releasing handle 0x%x", perfd_mode_handle);
        release_request(perfd_mode_handle);
        perfd_mode_handle = -1;
    }
    // switch to a perf mode
    hint_id = get_perfd_hint_id(mode);
    if (hint_id != 0) {
        perfd_mode_handle = perf_hint_enable(hint_id, 0);
        if (!CHECK_HANDLE(perfd_mode_handle)) {
            ALOGE("Failed perf_hint_interaction for mode: 0x%x", mode);
            return -1;
        }
        ALOGD("Acquired handle 0x%x", perfd_mode_handle);
    }
    return 0;
}

static int process_perf_hint(void *data, perf_mode_type_t mode) {
    // enable
    if (data) {
        ALOGI("Enable request for mode: 0x%x", mode);
        // check if mode is current mode
        if (current_mode & mode) {
            ALOGD("Mode 0x%x already enabled", mode);
            return HINT_HANDLED;
        }
        // enable requested mode
        if (0 != switch_mode(current_mode | mode)) {
            ALOGE("Couldn't enable mode 0x%x", mode);
            return HINT_NONE;
        }
        current_mode |= mode;
        ALOGI("Current mode is 0x%x", current_mode);
    // disable
    } else {
        ALOGI("Disable request for mode: 0x%x", mode);
        // check if mode is enabled
        if (!(current_mode & mode)) {
            ALOGD("Mode 0x%x already disabled", mode);
            return HINT_HANDLED;
        }
        // disable requested mode
        if (0 != switch_mode(current_mode & ~mode)) {
            ALOGE("Couldn't disable mode 0x%x", mode);
            return HINT_NONE;
        }
        current_mode &= ~mode;
        ALOGI("Current mode is 0x%x", current_mode);
    }

    return HINT_HANDLED;
}

static int process_video_encode_hint(void *metadata)
{
    char governor[80];
    struct video_encode_metadata_t video_encode_metadata;
    static int video_encode_handle = 0;

    if (!metadata) {
        return HINT_NONE;
    }

    if (get_scaling_governor(governor, sizeof(governor)) == -1) {
        ALOGE("Can't obtain scaling governor.");
        return HINT_NONE;
    }

    /* Initialize encode metadata struct fields */
    memset(&video_encode_metadata, 0, sizeof(struct video_encode_metadata_t));
    video_encode_metadata.state = -1;

    if (parse_video_encode_metadata((char *)metadata, &video_encode_metadata) == -1) {
        ALOGE("Error occurred while parsing metadata.");
        return HINT_NONE;
    }

    if (video_encode_metadata.state == 1) {
        if (is_interactive_governor(governor)) {
            video_encode_handle = perf_hint_enable(
                    VIDEO_ENCODE_HINT, 0);
            return HINT_HANDLED;
        }
    } else if (video_encode_metadata.state == 0) {
        if (is_interactive_governor(governor)) {
            release_request(video_encode_handle);
            return HINT_HANDLED;
        }
    }
    return HINT_NONE;
}

static int process_activity_launch_hint(void *data)
{
    static int launch_handle = -1;
    static int launch_mode = 0;

    // release lock early if launch has finished
    if (!data) {
        if (CHECK_HANDLE(launch_handle)) {
            release_request(launch_handle);
            launch_handle = -1;
        }
        launch_mode = 0;
        return HINT_HANDLED;
    }

    if (current_mode != NORMAL_MODE) {
        ALOGV("%s: ignoring due to other active perf hints", __func__);
    } else if (!launch_mode) {
        launch_handle = perf_hint_enable_with_type(VENDOR_HINT_FIRST_LAUNCH_BOOST,
                kMaxLaunchDuration, LAUNCH_BOOST_V1);
        if (!CHECK_HANDLE(launch_handle)) {
            ALOGE("Failed to perform launch boost");
            return HINT_NONE;
        }
        launch_mode = 1;
    }
    return HINT_HANDLED;
}

static int process_interaction_hint(void *data)
{
    static struct timespec s_previous_boost_timespec;
    static int s_previous_duration = 0;

    struct timespec cur_boost_timespec;
    long long elapsed_time;
    int duration = kMinInteractiveDuration;

    if (current_mode != NORMAL_MODE) {
        ALOGV("%s: ignoring due to other active perf hints", __func__);
        return HINT_HANDLED;
    }

    if (data) {
        int input_duration = *((int*)data);
        if (input_duration > duration) {
            duration = (input_duration > kMaxInteractiveDuration) ?
                    kMaxInteractiveDuration : input_duration;
        }
    }

    clock_gettime(CLOCK_MONOTONIC, &cur_boost_timespec);

    elapsed_time = calc_timespan_us(s_previous_boost_timespec, cur_boost_timespec);
    // don't hint if previous hint's duration covers this hint's duration
    if ((s_previous_duration * 1000) > (elapsed_time + duration * 1000)) {
        return HINT_HANDLED;
    }
    s_previous_boost_timespec = cur_boost_timespec;
    s_previous_duration = duration;

    perf_hint_enable_with_type(VENDOR_HINT_SCROLL_BOOST, duration, SCROLL_VERTICAL);

    return HINT_HANDLED;
}

int power_hint_override(power_hint_t hint, void *data)
{
    int ret_val = HINT_NONE;
    switch (hint) {
        case POWER_HINT_VIDEO_ENCODE:
            ret_val = process_video_encode_hint(data);
            break;
        case POWER_HINT_SUSTAINED_PERFORMANCE:
            ret_val = process_perf_hint(data, SUSTAINED_MODE);
            break;
        case POWER_HINT_VR_MODE:
            ret_val = process_perf_hint(data, VR_MODE);
            break;
        case POWER_HINT_INTERACTION:
            ret_val = process_interaction_hint(data);
            break;
        case POWER_HINT_LAUNCH:
            ret_val = process_activity_launch_hint(data);
            break;
        default:
            break;
    }
    return ret_val;
}

int set_interactive_override(int on)
{
    static const char *display_on = "1";
    static const char *display_off = "0";
    char err_buf[80];
    static int init_interactive_hint = 0;
    int rc = 0;

    if (init_interactive_hint == 0) {
        // First time the display is turned off
        display_fd = TEMP_FAILURE_RETRY(open(SYS_DISPLAY_PWR, O_RDWR));
        if (display_fd < 0) {
            strerror_r(errno, err_buf, sizeof(err_buf));
            ALOGE("Error opening %s: %s\n", SYS_DISPLAY_PWR, err_buf);
        } else {
            init_interactive_hint = 1;
        }
    } else {
        if (!on) {
            /* Display off. */
            rc = TEMP_FAILURE_RETRY(write(display_fd, display_off, strlen(display_off)));
            if (rc < 0) {
                strerror_r(errno, err_buf, sizeof(err_buf));
                ALOGE("Error writing %s to  %s: %s\n", display_off, SYS_DISPLAY_PWR, err_buf);
            }
        } else {
            /* Display on */
            rc = TEMP_FAILURE_RETRY(write(display_fd, display_on, strlen(display_on)));
            if (rc < 0) {
                strerror_r(errno, err_buf, sizeof(err_buf));
                ALOGE("Error writing %s to  %s: %s\n", display_on, SYS_DISPLAY_PWR, err_buf);
            }
        }
    }
    return HINT_HANDLED;
}