/*
 * Copyright (C) 2018 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 STATSD_DEBUG false
#include "Log.h"

#include "FieldValue.h"

#include "HashableDimensionKey.h"
#include "hash.h"
#include "math.h"

namespace android {
namespace os {
namespace statsd {

int32_t getEncodedField(int32_t pos[], int32_t depth, bool includeDepth) {
    int32_t field = 0;
    for (int32_t i = 0; i <= depth; i++) {
        int32_t shiftBits = 8 * (kMaxLogDepth - i);
        field |= (pos[i] << shiftBits);
    }

    if (includeDepth) {
        field |= (depth << 24);
    }
    return field;
}

int32_t encodeMatcherMask(int32_t mask[], int32_t depth) {
    return getEncodedField(mask, depth, false) | 0xff000000;
}

bool Field::matches(const Matcher& matcher) const {
    if (mTag != matcher.mMatcher.getTag()) {
        return false;
    }
    if ((mField & matcher.mMask) == matcher.mMatcher.getField()) {
        return true;
    }

    if (matcher.hasAllPositionMatcher() &&
        (mField & (matcher.mMask & kClearAllPositionMatcherMask)) == matcher.mMatcher.getField()) {
        return true;
    }

    return false;
}

void translateFieldMatcher(int tag, const FieldMatcher& matcher, int depth, int* pos, int* mask,
                           std::vector<Matcher>* output) {
    if (depth > kMaxLogDepth) {
        ALOGE("depth > 2");
        return;
    }

    pos[depth] = matcher.field();
    mask[depth] = 0x7f;

    if (matcher.has_position()) {
        depth++;
        if (depth > 2) {
            return;
        }
        switch (matcher.position()) {
            case Position::ALL:
                pos[depth] = 0x00;
                mask[depth] = 0x7f;
                break;
            case Position::ANY:
                pos[depth] = 0;
                mask[depth] = 0;
                break;
            case Position::FIRST:
                pos[depth] = 1;
                mask[depth] = 0x7f;
                break;
            case Position::LAST:
                pos[depth] = 0x80;
                mask[depth] = 0x80;
                break;
            case Position::POSITION_UNKNOWN:
                pos[depth] = 0;
                mask[depth] = 0;
                break;
        }
    }

    if (matcher.child_size() == 0) {
        output->push_back(Matcher(Field(tag, pos, depth), encodeMatcherMask(mask, depth)));
    } else {
        for (const auto& child : matcher.child()) {
            translateFieldMatcher(tag, child, depth + 1, pos, mask, output);
        }
    }
}

void translateFieldMatcher(const FieldMatcher& matcher, std::vector<Matcher>* output) {
    int pos[] = {1, 1, 1};
    int mask[] = {0x7f, 0x7f, 0x7f};
    int tag = matcher.field();
    for (const auto& child : matcher.child()) {
        translateFieldMatcher(tag, child, 0, pos, mask, output);
    }
}

bool isAttributionUidField(const FieldValue& value) {
    return isAttributionUidField(value.mField, value.mValue);
}

int32_t getUidIfExists(const FieldValue& value) {
    // the field is uid field if the field is the uid field in attribution node
    // or annotated as such in the atom
    bool isUid = isAttributionUidField(value) || isUidField(value);
    return isUid ? value.mValue.int_value : -1;
}

bool isAttributionUidField(const Field& field, const Value& value) {
    int f = field.getField() & 0xff007f;
    if (f == 0x10001 && value.getType() == INT) {
        return true;
    }
    return false;
}

bool isUidField(const FieldValue& fieldValue) {
    return fieldValue.mAnnotations.isUidField();
}

bool isPrimitiveRepeatedField(const Field& field) {
    return field.getDepth() == 1;
}

Value::Value(const Value& from) {
    type = from.getType();
    switch (type) {
        case INT:
            int_value = from.int_value;
            break;
        case LONG:
            long_value = from.long_value;
            break;
        case FLOAT:
            float_value = from.float_value;
            break;
        case DOUBLE:
            double_value = from.double_value;
            break;
        case STRING:
            str_value = from.str_value;
            break;
        case STORAGE:
            storage_value = from.storage_value;
            break;
        default:
            break;
    }
}

std::string Value::toString() const {
    switch (type) {
        case INT:
            return std::to_string(int_value) + "[I]";
        case LONG:
            return std::to_string(long_value) + "[L]";
        case FLOAT:
            return std::to_string(float_value) + "[F]";
        case DOUBLE:
            return std::to_string(double_value) + "[D]";
        case STRING:
            return str_value + "[S]";
        case STORAGE:
            return "bytes of size " + std::to_string(storage_value.size()) + "[ST]";
        default:
            return "[UNKNOWN]";
    }
}

bool Value::isZero() const {
    switch (type) {
        case INT:
            return int_value == 0;
        case LONG:
            return long_value == 0;
        case FLOAT:
            return fabs(float_value) <= std::numeric_limits<float>::epsilon();
        case DOUBLE:
            return fabs(double_value) <= std::numeric_limits<double>::epsilon();
        case STRING:
            return str_value.size() == 0;
        case STORAGE:
            return storage_value.size() == 0;
        default:
            return false;
    }
}

bool Value::operator==(const Value& that) const {
    if (type != that.getType()) return false;

    switch (type) {
        case INT:
            return int_value == that.int_value;
        case LONG:
            return long_value == that.long_value;
        case FLOAT:
            return float_value == that.float_value;
        case DOUBLE:
            return double_value == that.double_value;
        case STRING:
            return str_value == that.str_value;
        case STORAGE:
            return storage_value == that.storage_value;
        default:
            return false;
    }
}

bool Value::operator!=(const Value& that) const {
    if (type != that.getType()) return true;
    switch (type) {
        case INT:
            return int_value != that.int_value;
        case LONG:
            return long_value != that.long_value;
        case FLOAT:
            return float_value != that.float_value;
        case DOUBLE:
            return double_value != that.double_value;
        case STRING:
            return str_value != that.str_value;
        case STORAGE:
            return storage_value != that.storage_value;
        default:
            return false;
    }
}

bool Value::operator<(const Value& that) const {
    if (type != that.getType()) return type < that.getType();

    switch (type) {
        case INT:
            return int_value < that.int_value;
        case LONG:
            return long_value < that.long_value;
        case FLOAT:
            return float_value < that.float_value;
        case DOUBLE:
            return double_value < that.double_value;
        case STRING:
            return str_value < that.str_value;
        case STORAGE:
            return storage_value < that.storage_value;
        default:
            return false;
    }
}

bool Value::operator>(const Value& that) const {
    if (type != that.getType()) return type > that.getType();

    switch (type) {
        case INT:
            return int_value > that.int_value;
        case LONG:
            return long_value > that.long_value;
        case FLOAT:
            return float_value > that.float_value;
        case DOUBLE:
            return double_value > that.double_value;
        case STRING:
            return str_value > that.str_value;
        case STORAGE:
            return storage_value > that.storage_value;
        default:
            return false;
    }
}

bool Value::operator>=(const Value& that) const {
    if (type != that.getType()) return type >= that.getType();

    switch (type) {
        case INT:
            return int_value >= that.int_value;
        case LONG:
            return long_value >= that.long_value;
        case FLOAT:
            return float_value >= that.float_value;
        case DOUBLE:
            return double_value >= that.double_value;
        case STRING:
            return str_value >= that.str_value;
        case STORAGE:
            return storage_value >= that.storage_value;
        default:
            return false;
    }
}

Value Value::operator-(const Value& that) const {
    Value v;
    if (type != that.type) {
        ALOGE("Can't operate on different value types, %d, %d", type, that.type);
        return v;
    }
    if (type == STRING) {
        ALOGE("Can't operate on string value type");
        return v;
    }

    if (type == STORAGE) {
        ALOGE("Can't operate on storage value type");
        return v;
    }

    switch (type) {
        case INT:
            v.setInt(int_value - that.int_value);
            break;
        case LONG:
            v.setLong(long_value - that.long_value);
            break;
        case FLOAT:
            v.setFloat(float_value - that.float_value);
            break;
        case DOUBLE:
            v.setDouble(double_value - that.double_value);
            break;
        default:
            break;
    }
    return v;
}

Value& Value::operator=(const Value& that) {
    if (this != &that) {
        type = that.type;
        switch (type) {
            case INT:
                int_value = that.int_value;
                break;
            case LONG:
                long_value = that.long_value;
                break;
            case FLOAT:
                float_value = that.float_value;
                break;
            case DOUBLE:
                double_value = that.double_value;
                break;
            case STRING:
                str_value = that.str_value;
                break;
            case STORAGE:
                storage_value = that.storage_value;
                break;
            default:
                break;
        }
    }
    return *this;
}

Value& Value::operator+=(const Value& that) {
    if (type != that.type) {
        ALOGE("Can't operate on different value types, %d, %d", type, that.type);
        return *this;
    }
    if (type == STRING) {
        ALOGE("Can't operate on string value type");
        return *this;
    }
    if (type == STORAGE) {
        ALOGE("Can't operate on storage value type");
        return *this;
    }

    switch (type) {
        case INT:
            int_value += that.int_value;
            break;
        case LONG:
            long_value += that.long_value;
            break;
        case FLOAT:
            float_value += that.float_value;
            break;
        case DOUBLE:
            double_value += that.double_value;
            break;
        default:
            break;
    }
    return *this;
}

double Value::getDouble() const {
    switch (type) {
        case INT:
            return int_value;
        case LONG:
            return long_value;
        case FLOAT:
            return float_value;
        case DOUBLE:
            return double_value;
        default:
            return 0;
    }
}

size_t Value::getSize() const {
    size_t size = 0;
    switch (type) {
        case INT:
            size = sizeof(int32_t);
            break;
        case LONG:
            size = sizeof(int64_t);
            break;
        case FLOAT:
            size = sizeof(float);
            break;
        case DOUBLE:
            size = sizeof(double);
            break;
        case STRING:
            size = sizeof(char) * str_value.length();
            break;
        case STORAGE:
            size = sizeof(uint8_t) * storage_value.size();
            break;
        default:
            break;
    }
    return size;
}

std::string Annotations::toString() const {
    std::string annotations;
    if (isUidField()) {
        annotations += "UID";
    }
    if (isPrimaryField()) {
        annotations += annotations.size() > 0 ? ",PRIMARY" : "PRIMARY";
    }
    if (isExclusiveState()) {
        annotations += annotations.size() > 0 ? ",EXCLUSIVE" : "EXCLUSIVE";
    }
    if (isNested()) {
        annotations += annotations.size() > 0 ? ",NESTED" : "NESTED";
    }
    if (annotations.size()) {
        annotations = "[" + annotations + "]";
    }
    return annotations;
}

bool equalDimensions(const std::vector<Matcher>& dimension_a,
                     const std::vector<Matcher>& dimension_b) {
    bool eq = dimension_a.size() == dimension_b.size();
    for (size_t i = 0; eq && i < dimension_a.size(); ++i) {
        if (dimension_b[i] != dimension_a[i]) {
            eq = false;
        }
    }
    return eq;
}

/* Is dimension_a a subset of dimension_b. */
bool subsetDimensions(const std::vector<Matcher>& dimension_a,
                      const std::vector<Matcher>& dimension_b) {
    if (dimension_a.size() > dimension_b.size()) {
        return false;
    }
    for (size_t i = 0; i < dimension_a.size(); ++i) {
        bool found = false;
        for (size_t j = 0; j < dimension_b.size(); ++j) {
            if (dimension_a[i] == dimension_b[j]) {
                found = true;
                break;
            }

            // Check equality of repeated fields with different positions.
            // Only position FIRST and LAST are considered subsets of position ALL.
            if (dimension_b[j].hasAllPositionMatcher() &&
                (dimension_a[i].hasFirstPositionMatcher() ||
                 dimension_a[i].hasLastPositionMatcher())) {
                if (dimension_a[i].isEqualWithoutPositionBits(dimension_b[j])) {
                    found = true;
                    break;
                }
            }
        }
        if (!found) {
            return false;
        }
    }
    return true;
}

bool HasPositionANY(const FieldMatcher& matcher) {
    if (matcher.has_position() && matcher.position() == Position::ANY) {
        return true;
    }
    for (const auto& child : matcher.child()) {
        if (HasPositionANY(child)) {
            return true;
        }
    }
    return false;
}

bool HasPositionALL(const FieldMatcher& matcher) {
    if (matcher.has_position() && matcher.position() == Position::ALL) {
        return true;
    }
    for (const auto& child : matcher.child()) {
        if (HasPositionALL(child)) {
            return true;
        }
    }
    return false;
}

bool HasPrimitiveRepeatedField(const FieldMatcher& matcher) {
    for (const auto& child : matcher.child()) {
        if (child.has_position() && child.child_size() == 0) {
            return true;
        }
    }
    return false;
}

bool ShouldUseNestedDimensions(const FieldMatcher& matcher) {
    return HasPositionALL(matcher) || HasPrimitiveRepeatedField(matcher);
}

size_t getSize(const std::vector<FieldValue>& fieldValues) {
    size_t totalSize = 0;
    for (const FieldValue& fieldValue : fieldValues) {
        totalSize += fieldValue.getSize();
    }
    return totalSize;
}

bool shouldKeepSample(const FieldValue& sampleFieldValue, int shardOffset, int shardCount) {
    int hashValue = 0;
    switch (sampleFieldValue.mValue.type) {
        case INT:
            hashValue = Hash32(reinterpret_cast<const char*>(&sampleFieldValue.mValue.int_value),
                               sizeof(sampleFieldValue.mValue.int_value));
            break;
        case LONG:
            hashValue = Hash32(reinterpret_cast<const char*>(&sampleFieldValue.mValue.long_value),
                               sizeof(sampleFieldValue.mValue.long_value));
            break;
        case FLOAT:
            hashValue = Hash32(reinterpret_cast<const char*>(&sampleFieldValue.mValue.float_value),
                               sizeof(sampleFieldValue.mValue.float_value));
            break;
        case DOUBLE:
            hashValue = Hash32(reinterpret_cast<const char*>(&sampleFieldValue.mValue.double_value),
                               sizeof(sampleFieldValue.mValue.double_value));
            break;
        case STRING:
            hashValue = Hash32(sampleFieldValue.mValue.str_value);
            break;
        case STORAGE:
            hashValue = Hash32((const char*)sampleFieldValue.mValue.storage_value.data(),
                               sampleFieldValue.mValue.storage_value.size());
            break;
        default:
            return true;
    }
    return (hashValue + shardOffset) % shardCount == 0;
}

}  // namespace statsd
}  // namespace os
}  // namespace android