/*
 * Copyright (C) 2019 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.
 */

package com.android.car.pm;

import android.annotation.IntDef;
import android.content.ComponentName;
import android.content.Intent;
import android.text.TextUtils;

import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;

/**
 * Describes configuration of the vendor service that needs to be started by Car Service. This is
 * immutable object to store only service configuration.
 */
class VendorServiceInfo {
    private static final String KEY_BIND = "bind";
    private static final String KEY_USER_SCOPE = "user";
    private static final String KEY_TRIGGER = "trigger";

    private static final int USER_SCOPE_ALL = 0;
    private static final int USER_SCOPE_SYSTEM = 1;
    private static final int USER_SCOPE_FOREGROUND = 2;
    @Retention(RetentionPolicy.SOURCE)
    @IntDef({
            USER_SCOPE_ALL,
            USER_SCOPE_FOREGROUND,
            USER_SCOPE_SYSTEM,
    })
    @interface UserScope {}

    private static final int TRIGGER_ASAP = 0;
    private static final int TRIGGER_UNLOCKED = 1;
    @Retention(RetentionPolicy.SOURCE)
    @IntDef({
            TRIGGER_ASAP,
            TRIGGER_UNLOCKED,
    })
    @interface Trigger {}

    private static final int BIND = 0;
    private static final int START = 1;
    private static final int START_FOREGROUND = 2;
    @Retention(RetentionPolicy.SOURCE)
    @IntDef({
            BIND,
            START,
            START_FOREGROUND,
    })
    @interface Bind {}

    private final @Bind int mBind;
    private final @UserScope int mUserScope;
    private final @Trigger int mTrigger;
    private final ComponentName mComponentName;

    private VendorServiceInfo(ComponentName componentName, @Bind int bind, @UserScope int userScope,
            @Trigger int trigger) {
        mComponentName = componentName;
        mUserScope = userScope;
        mTrigger = trigger;
        mBind = bind;
    }

    boolean isSystemUserService() {
        return mUserScope == USER_SCOPE_ALL || mUserScope == USER_SCOPE_SYSTEM;
    }

    boolean isForegroundUserService() {
        return mUserScope == USER_SCOPE_ALL || mUserScope == USER_SCOPE_FOREGROUND;
    }

    boolean shouldStartOnUnlock() {
        return mTrigger == TRIGGER_UNLOCKED;
    }

    boolean shouldStartAsap() {
        return mTrigger == TRIGGER_ASAP;
    }

    boolean shouldBeBound() {
        return mBind == BIND;
    }

    boolean shouldBeStartedInForeground() {
        return mBind == START_FOREGROUND;
    }

    Intent getIntent() {
        Intent intent = new Intent();
        intent.setComponent(mComponentName);
        return intent;
    }

    static VendorServiceInfo parse(String rawServiceInfo) {
        String[] serviceParamTokens = rawServiceInfo.split("#");
        if (serviceParamTokens.length < 1 || serviceParamTokens.length > 2) {
            throw new IllegalArgumentException("Failed to parse service info: "
                    + rawServiceInfo + ", expected a single '#' symbol");

        }

        final ComponentName cn = ComponentName.unflattenFromString(serviceParamTokens[0]);
        if (cn == null) {
            throw new IllegalArgumentException("Failed to unflatten component name from: "
                    + rawServiceInfo);
        }

        int bind = START;
        int userScope = USER_SCOPE_ALL;
        int trigger = TRIGGER_UNLOCKED;

        if (serviceParamTokens.length == 2) {
            for (String keyValueStr : serviceParamTokens[1].split(",")) {
                String[] pair = keyValueStr.split("=");
                String key = pair[0];
                String val = pair[1];
                if (TextUtils.isEmpty(key)) {
                    continue;
                }

                switch (key) {
                    case KEY_BIND:
                        if ("bind".equals(val)) {
                            bind = BIND;
                        } else if ("start".equals(val)) {
                            bind = START;
                        } else if ("startForeground".equals(val)) {
                            bind = START_FOREGROUND;
                        } else {
                            throw new IllegalArgumentException("Unexpected bind option: " + val);
                        }
                        break;
                    case KEY_USER_SCOPE:
                        if ("all".equals(val)) {
                            userScope = USER_SCOPE_ALL;
                        } else if ("system".equals(val)) {
                            userScope = USER_SCOPE_SYSTEM;
                        } else if ("foreground".equals(val)) {
                            userScope = USER_SCOPE_FOREGROUND;
                        } else {
                            throw new IllegalArgumentException("Unexpected user scope: " + val);
                        }
                        break;
                    case KEY_TRIGGER:
                        if ("asap".equals(val)) {
                            trigger = TRIGGER_ASAP;
                        } else if ("userUnlocked".equals(val)) {
                            trigger = TRIGGER_UNLOCKED;
                        } else {
                            throw new IllegalArgumentException("Unexpected trigger: " + val);
                        }
                        break;
                    default:
                        throw new IllegalArgumentException("Unexpected token: " + key);
                }
            }
        }

        return new VendorServiceInfo(cn, bind, userScope, trigger);
    }

    @Override
    public String toString() {
        return "VendorService{"
                + "component=" + mComponentName
                + ", bind=" + mBind
                + ", trigger=" + mTrigger
                + ", user=" + mUserScope
                + '}';
    }

    String toShortString() {
        return mComponentName != null ? mComponentName.toShortString() : "";
    }
}