/*
 * Copyright (C) 2013 The Android Open Source 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_TAG "memtrack"
#include <android/hardware/memtrack/1.0/IMemtrack.h>
#include <memtrack/memtrack.h>

#include <errno.h>
#include <malloc.h>
#include <vector>
#include <string.h>
#include <mutex>

using android::hardware::memtrack::V1_0::IMemtrack;
using android::hardware::memtrack::V1_0::MemtrackType;
using android::hardware::memtrack::V1_0::MemtrackRecord;
using android::hardware::memtrack::V1_0::MemtrackFlag;
using android::hardware::memtrack::V1_0::MemtrackStatus;
using android::hardware::hidl_vec;

struct memtrack_proc_type {
    MemtrackType type;
    std::vector<MemtrackRecord> records;
};

struct memtrack_proc {
    pid_t pid;
    memtrack_proc_type types[static_cast<int>(MemtrackType::NUM_TYPES)];
};

//TODO(b/31632518)
static android::sp<IMemtrack> get_instance() {
    static android::sp<IMemtrack> module = IMemtrack::getService("memtrack");
    if (module == nullptr) {
        ALOGE("Couldn't load memtrack module");
    }
    return module;
}

memtrack_proc *memtrack_proc_new(void)
{
    return new memtrack_proc();
}

void memtrack_proc_destroy(memtrack_proc *p)
{
    delete(p);
}

static int memtrack_proc_get_type(memtrack_proc_type *t,
        pid_t pid, MemtrackType type)
{
    int err = 0;
    android::sp<IMemtrack> memtrack = get_instance();
    if (memtrack == nullptr)
        return -1;

    memtrack->getMemory(pid, type,
        [&t, &err](MemtrackStatus status, hidl_vec<MemtrackRecord> records) {
            if (status != MemtrackStatus::SUCCESS) {
                err = -1;
                t->records.resize(0);
            }
            t->records.resize(records.size());
            for (size_t i = 0; i < records.size(); i++) {
                t->records[i].sizeInBytes = records[i].sizeInBytes;
                t->records[i].flags = records[i].flags;
            }
    });
    return err;
}

/* TODO: sanity checks on return values from HALs:
 *   make sure no records have invalid flags set
 *    - unknown flags
 *    - too many flags of a single category
 *    - missing ACCOUNTED/UNACCOUNTED
 *   make sure there are not overlapping SHARED and SHARED_PSS records
 */
static int memtrack_proc_sanity_check(memtrack_proc* /*p*/)
{
    return 0;
}

int memtrack_proc_get(memtrack_proc *p, pid_t pid)
{
    if (!p) {
        return -EINVAL;
    }

    p->pid = pid;
    for (uint32_t i = 0; i < (uint32_t)MemtrackType::NUM_TYPES; i++) {
        int ret = memtrack_proc_get_type(&p->types[i], pid, (MemtrackType)i);
        if (ret != 0)
           return ret;
    }

    return memtrack_proc_sanity_check(p);
}

static ssize_t memtrack_proc_sum(memtrack_proc *p,
        const std::vector<MemtrackType>& types, uint32_t flags)
{
    ssize_t sum = 0;

    for (size_t i = 0; i < types.size(); i++) {
        memtrack_proc_type type = p->types[static_cast<int>(types[i])];
        std::vector<MemtrackRecord> records = type.records;
        for (size_t j = 0; j < records.size(); j++) {
            if ((records[j].flags & flags) == flags) {
                sum += records[j].sizeInBytes;
            }
        }
    }

    return sum;
}

ssize_t memtrack_proc_graphics_total(memtrack_proc *p)
{
    std::vector<MemtrackType> types = {MemtrackType::GRAPHICS};
    return memtrack_proc_sum(p, types, 0);
}

ssize_t memtrack_proc_graphics_pss(memtrack_proc *p)
{
    std::vector<MemtrackType> types = { MemtrackType::GRAPHICS };
    return memtrack_proc_sum(p, types,
            (uint32_t)MemtrackFlag::SMAPS_UNACCOUNTED);
}

ssize_t memtrack_proc_gl_total(memtrack_proc *p)
{
    std::vector<MemtrackType> types = { MemtrackType::GL };
    return memtrack_proc_sum(p, types, 0);
}

ssize_t memtrack_proc_gl_pss(memtrack_proc *p)
{
    std::vector<MemtrackType> types = { MemtrackType::GL };
    return memtrack_proc_sum(p, types,
            (uint32_t)MemtrackFlag::SMAPS_UNACCOUNTED);
}

ssize_t memtrack_proc_other_total(memtrack_proc *p)
{
    std::vector<MemtrackType> types = { MemtrackType::MULTIMEDIA,
            MemtrackType::CAMERA, MemtrackType::OTHER };
    return memtrack_proc_sum(p, types, 0);
}

ssize_t memtrack_proc_other_pss(memtrack_proc *p)
{
    std::vector<MemtrackType> types = { MemtrackType::MULTIMEDIA,
            MemtrackType::CAMERA, MemtrackType::OTHER };
    return memtrack_proc_sum(p, types,
            (uint32_t)MemtrackFlag::SMAPS_UNACCOUNTED);
}