com.github.hilcode.versionator.impl.DefaultFlagExtractor.java Source code

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Here is the source code for com.github.hilcode.versionator.impl.DefaultFlagExtractor.java

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/*
 * Copyright (C) 2016 H.C. Wijbenga
 *
 * 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.github.hilcode.versionator.impl;

import static com.github.hilcode.versionator.api.Command.RELEASE;
import static com.github.hilcode.versionator.api.Command.SET_VERSION;
import static com.github.hilcode.versionator.api.Mode.AUTOMATIC;
import static com.github.hilcode.versionator.api.Mode.INTERACTIVE;
import static com.github.hilcode.versionator.api.RunType.ACTUAL;
import static com.github.hilcode.versionator.api.RunType.DRY_RUN;
import com.github.hilcode.versionator.api.Command;
import com.github.hilcode.versionator.api.FlagExtractor;
import com.github.hilcode.versionator.api.Flags;
import com.github.hilcode.versionator.api.Mode;
import com.github.hilcode.versionator.api.RunType;
import com.github.hilcode.versionator.misc.Result;
import com.google.common.base.Preconditions;
import com.google.common.collect.ImmutableList;

public final class DefaultFlagExtractor implements FlagExtractor {
    private final Flags.Builder flagsBuilder;

    public DefaultFlagExtractor(final Flags.Builder flagsBuilder) {
        this.flagsBuilder = flagsBuilder;
    }

    @Override
    public Result<String, Flags> extract(final ImmutableList<String> arguments) {
        Preconditions.checkNotNull(arguments, "Missing 'arguments'.");
        if (arguments.isEmpty()) {
            return Result.failure("No arguments provided.\n\nPerhaps try --help?");
        } else {
            final ImmutableList.Builder<String> expandedArgumentsBuilder = ImmutableList.builder();
            for (final String argument : arguments) {
                if (argument.startsWith("-") && !argument.startsWith("--") && argument.length() > 2) {
                    for (int i = 1; i < argument.length(); i++) {
                        expandedArgumentsBuilder.add("-" + argument.charAt(i));
                    }
                } else {
                    expandedArgumentsBuilder.add(argument);
                }
            }
            return extractFlags(expandedArgumentsBuilder.build());
        }
    }

    Result<String, Flags> extractFlags(final ImmutableList<String> arguments) {
        final ImmutableList.Builder<String> argumentsBuilder = ImmutableList.builder();
        RunType runType = ACTUAL;
        Mode mode = AUTOMATIC;
        String commandAsText = "";
        for (final String arg : arguments) {
            if (arg.equals("-h") || arg.equals("--help")) {
                return Result.failure(Usage.INSTANCE.toString());
            } else if (arg.equals("-n") || arg.equals("--dry-run")) {
                runType = DRY_RUN;
            } else if (arg.equals("-i") || arg.equals("--interactive")) {
                mode = INTERACTIVE;
            } else {
                if (commandAsText.isEmpty()) {
                    commandAsText = arg;
                } else {
                    argumentsBuilder.add(arg);
                }
            }
        }
        return extractCommand(argumentsBuilder, runType, mode, commandAsText);
    }

    Result<String, Flags> extractCommand(final ImmutableList.Builder<String> argumentsBuilder,
            final RunType runType, final Mode mode, final String commandAsText) {
        if (commandAsText.isEmpty()) {
            return Result
                    .failure("Missing command, expected either 'set-version' or 'release'.\n\nPerhaps try --help?");
        } else {
            final ImmutableList<String> arguments = argumentsBuilder.build();
            final Result<String, Command> command = extractCommand(commandAsText);
            if (command.isFailure()) {
                return Result.asFailure(command);
            } else {
                return Result.success(this.flagsBuilder.build(runType, mode, command.success(), arguments));
            }
        }
    }

    Result<String, Command> extractCommand(final String commandAsText) {
        if (commandAsText.equals("set-version")) {
            return Result.success(SET_VERSION);
        } else if (commandAsText.equals("release")) {
            return Result.success(RELEASE);
        } else {
            final String message = String.format(commandAsText.startsWith("-") ? "Unknown flag: '%s'."
                    : "Invalid command: '%s' (only 'set-version' and 'release' are valid).", commandAsText);
            return Result.failure(message + "\n\nPerhaps try --help?");
        }
    }
}