/*
 * Copyright (c) 2013, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

package jdk.testlibrary;

import static jdk.testlibrary.Asserts.*;

import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

/**
 * Utility class for verifying output and exit value from a {@code Process}.
 */
public final class OutputAnalyzer {

    private final String stdout;
    private final String stderr;
    private final int exitValue;

    /**
     * Create an OutputAnalyzer, a utility class for verifying output and exit
     * value from a Process
     *
     * @param process
     *            Process to analyze
     * @throws IOException
     *             If an I/O error occurs.
     */
    public OutputAnalyzer(Process process) throws IOException {
        OutputBuffer output = ProcessTools.getOutput(process);
        exitValue = process.exitValue();
        this.stdout = output.getStdout();
        this.stderr = output.getStderr();
    }

    /**
     * Create an OutputAnalyzer, a utility class for verifying output
     *
     * @param buf
     *            String buffer to analyze
     */
    public OutputAnalyzer(String buf) {
        this(buf, buf);
    }

    /**
     * Create an OutputAnalyzer, a utility class for verifying output
     *
     * @param stdout
     *            stdout buffer to analyze
     * @param stderr
     *            stderr buffer to analyze
     */
    public OutputAnalyzer(String stdout, String stderr) {
        this.stdout = stdout;
        this.stderr = stderr;
        exitValue = -1;
    }

    /**
     * Verify that the stdout and stderr contents of output buffer contains the
     * string
     *
     * @param expectedString
     *            String that buffer should contain
     * @throws RuntimeException
     *             If the string was not found
     */
    public void shouldContain(String expectedString) {
        if (!stdout.contains(expectedString)
                && !stderr.contains(expectedString)) {
            reportDiagnosticSummary();
            throw new RuntimeException("'" + expectedString
                    + "' missing from stdout/stderr \n");
        }
    }

    /**
     * Verify that the stdout contents of output buffer contains the string
     *
     * @param expectedString
     *            String that buffer should contain
     * @throws RuntimeException
     *             If the string was not found
     */
    public void stdoutShouldContain(String expectedString) {
        if (!stdout.contains(expectedString)) {
            reportDiagnosticSummary();
            throw new RuntimeException("'" + expectedString
                    + "' missing from stdout \n");
        }
    }

    /**
     * Verify that the stderr contents of output buffer contains the string
     *
     * @param expectedString
     *            String that buffer should contain
     * @throws RuntimeException
     *             If the string was not found
     */
    public void stderrShouldContain(String expectedString) {
        if (!stderr.contains(expectedString)) {
            reportDiagnosticSummary();
            throw new RuntimeException("'" + expectedString
                    + "' missing from stderr \n");
        }
    }

    /**
     * Verify that the stdout and stderr contents of output buffer does not
     * contain the string
     *
     * @param expectedString
     *            String that the buffer should not contain
     * @throws RuntimeException
     *             If the string was found
     */
    public void shouldNotContain(String notExpectedString) {
        if (stdout.contains(notExpectedString)) {
            reportDiagnosticSummary();
            throw new RuntimeException("'" + notExpectedString
                    + "' found in stdout \n");
        }
        if (stderr.contains(notExpectedString)) {
            reportDiagnosticSummary();
            throw new RuntimeException("'" + notExpectedString
                    + "' found in stderr \n");
        }
    }

    /**
     * Verify that the stdout contents of output buffer does not contain the
     * string
     *
     * @param expectedString
     *            String that the buffer should not contain
     * @throws RuntimeException
     *             If the string was found
     */
    public void stdoutShouldNotContain(String notExpectedString) {
        if (stdout.contains(notExpectedString)) {
            reportDiagnosticSummary();
            throw new RuntimeException("'" + notExpectedString
                    + "' found in stdout \n");
        }
    }

    /**
     * Verify that the stderr contents of output buffer does not contain the
     * string
     *
     * @param expectedString
     *            String that the buffer should not contain
     * @throws RuntimeException
     *             If the string was found
     */
    public void stderrShouldNotContain(String notExpectedString) {
        if (stderr.contains(notExpectedString)) {
            reportDiagnosticSummary();
            throw new RuntimeException("'" + notExpectedString
                    + "' found in stderr \n");
        }
    }

    /**
     * Verify that the stdout and stderr contents of output buffer matches the
     * pattern
     *
     * @param pattern
     * @throws RuntimeException
     *             If the pattern was not found
     */
    public void shouldMatch(String pattern) {
        Matcher stdoutMatcher = Pattern.compile(pattern, Pattern.MULTILINE)
                .matcher(stdout);
        Matcher stderrMatcher = Pattern.compile(pattern, Pattern.MULTILINE)
                .matcher(stderr);
        if (!stdoutMatcher.find() && !stderrMatcher.find()) {
            reportDiagnosticSummary();
            throw new RuntimeException("'" + pattern
                    + "' missing from stdout/stderr \n");
        }
    }

    /**
     * Verify that the stdout contents of output buffer matches the pattern
     *
     * @param pattern
     * @throws RuntimeException
     *             If the pattern was not found
     */
    public void stdoutShouldMatch(String pattern) {
        Matcher matcher = Pattern.compile(pattern, Pattern.MULTILINE).matcher(
                stdout);
        if (!matcher.find()) {
            reportDiagnosticSummary();
            throw new RuntimeException("'" + pattern
                    + "' missing from stdout \n");
        }
    }

    /**
     * Verify that the stderr contents of output buffer matches the pattern
     *
     * @param pattern
     * @throws RuntimeException
     *             If the pattern was not found
     */
    public void stderrShouldMatch(String pattern) {
        Matcher matcher = Pattern.compile(pattern, Pattern.MULTILINE).matcher(
                stderr);
        if (!matcher.find()) {
            reportDiagnosticSummary();
            throw new RuntimeException("'" + pattern
                    + "' missing from stderr \n");
        }
    }

    /**
     * Verify that the stdout and stderr contents of output buffer does not
     * match the pattern
     *
     * @param pattern
     * @throws RuntimeException
     *             If the pattern was found
     */
    public void shouldNotMatch(String pattern) {
        Matcher matcher = Pattern.compile(pattern, Pattern.MULTILINE).matcher(
                stdout);
        if (matcher.find()) {
            reportDiagnosticSummary();
            throw new RuntimeException("'" + pattern + "' found in stdout: '"
                    + matcher.group() + "' \n");
        }
        matcher = Pattern.compile(pattern, Pattern.MULTILINE).matcher(stderr);
        if (matcher.find()) {
            reportDiagnosticSummary();
            throw new RuntimeException("'" + pattern + "' found in stderr: '"
                    + matcher.group() + "' \n");
        }
    }

    /**
     * Verify that the stdout contents of output buffer does not match the
     * pattern
     *
     * @param pattern
     * @throws RuntimeException
     *             If the pattern was found
     */
    public void stdoutShouldNotMatch(String pattern) {
        Matcher matcher = Pattern.compile(pattern, Pattern.MULTILINE).matcher(
                stdout);
        if (matcher.find()) {
            reportDiagnosticSummary();
            throw new RuntimeException("'" + pattern + "' found in stdout \n");
        }
    }

    /**
     * Verify that the stderr contents of output buffer does not match the
     * pattern
     *
     * @param pattern
     * @throws RuntimeException
     *             If the pattern was found
     */
    public void stderrShouldNotMatch(String pattern) {
        Matcher matcher = Pattern.compile(pattern, Pattern.MULTILINE).matcher(
                stderr);
        if (matcher.find()) {
            reportDiagnosticSummary();
            throw new RuntimeException("'" + pattern + "' found in stderr \n");
        }
    }

    /**
     * Get the captured group of the first string matching the pattern. stderr
     * is searched before stdout.
     *
     * @param pattern
     *            The multi-line pattern to match
     * @param group
     *            The group to capture
     * @return The matched string or null if no match was found
     */
    public String firstMatch(String pattern, int group) {
        Matcher stderrMatcher = Pattern.compile(pattern, Pattern.MULTILINE)
                .matcher(stderr);
        Matcher stdoutMatcher = Pattern.compile(pattern, Pattern.MULTILINE)
                .matcher(stdout);
        if (stderrMatcher.find()) {
            return stderrMatcher.group(group);
        }
        if (stdoutMatcher.find()) {
            return stdoutMatcher.group(group);
        }
        return null;
    }

    /**
     * Get the first string matching the pattern. stderr is searched before
     * stdout.
     *
     * @param pattern
     *            The multi-line pattern to match
     * @return The matched string or null if no match was found
     */
    public String firstMatch(String pattern) {
        return firstMatch(pattern, 0);
    }

    /**
     * Verify the exit value of the process
     *
     * @param expectedExitValue
     *            Expected exit value from process
     * @throws RuntimeException
     *             If the exit value from the process did not match the expected
     *             value
     */
    public void shouldHaveExitValue(int expectedExitValue) {
        if (getExitValue() != expectedExitValue) {
            reportDiagnosticSummary();
            throw new RuntimeException("Expected to get exit value of ["
                    + expectedExitValue + "]\n");
        }
    }

    /**
     * Report summary that will help to diagnose the problem Currently includes:
     * - standard input produced by the process under test - standard output -
     * exit code Note: the command line is printed by the ProcessTools
     */
    private void reportDiagnosticSummary() {
        String msg = " stdout: [" + stdout + "];\n" + " stderr: [" + stderr
                + "]\n" + " exitValue = " + getExitValue() + "\n";

        System.err.println(msg);
    }

    /**
     * Get the contents of the output buffer (stdout and stderr)
     *
     * @return Content of the output buffer
     */
    public String getOutput() {
        return stdout + stderr;
    }

    /**
     * Get the contents of the stdout buffer
     *
     * @return Content of the stdout buffer
     */
    public String getStdout() {
        return stdout;
    }

    /**
     * Get the contents of the stderr buffer
     *
     * @return Content of the stderr buffer
     */
    public String getStderr() {
        return stderr;
    }

    /**
     * Get the process exit value
     *
     * @return Process exit value
     */
    public int getExitValue() {
        return exitValue;
    }

    /**
     * Get the contents of the output buffer (stdout and stderr) as list of strings.
     * Output will be split by system property 'line.separator'.
     *
     * @return Contents of the output buffer as list of strings
     */
    public List<String> asLines() {
        List<String> l = new ArrayList<>();
        String[] a = getOutput().split(Utils.NEW_LINE);
        for (String string : a) {
            l.add(string);
        }
        return l;
    }

    /**
     * Check if there is a line matching {@code pattern} and return its index
     *
     * @param pattern Matching pattern
     * @return Index of first matching line
     */
    private int indexOf(List<String> lines, String pattern) {
        for (int i = 0; i < lines.size(); i++) {
            if (lines.get(i).matches(pattern)) {
                return i;
            }
        }
        return -1;
    }

    /**
     * @see #shouldMatchByLine(String, String, String)
     */
    public int shouldMatchByLine(String pattern) {
        return shouldMatchByLine(null, null, pattern);
    }

    /**
     * @see #shouldMatchByLine(String, String, String)
     */
    public int shouldMatchByLineFrom(String from, String pattern) {
        return shouldMatchByLine(from, null, pattern);
    }

    /**
     * @see #shouldMatchByLine(String, String, String)
     */
    public int shouldMatchByLineTo(String to, String pattern) {
        return shouldMatchByLine(null, to, pattern);
    }

    /**
     * Verify that the stdout and stderr contents of output buffer match the
     * {@code pattern} line by line. The whole output could be matched or
     * just a subset of it.
     *
     * @param from
     *            The line from where output will be matched.
     *            Set {@code from} to null for matching from the first line.
     * @param to
     *            The line until where output will be matched.
     *            Set {@code to} to null for matching until the last line.
     * @param pattern
     *            Matching pattern
     * @return Count of lines which match the {@code pattern}
     */
    public int shouldMatchByLine(String from, String to, String pattern) {
        List<String> lines = asLines();

        int fromIndex = 0;
        if (from != null) {
            fromIndex = indexOf(lines, from);
            assertGreaterThan(fromIndex, -1,
                    "The line/pattern '" + from + "' from where the output should match can not be found");
        }

        int toIndex = lines.size();
        if (to != null) {
            toIndex = indexOf(lines, to);
            assertGreaterThan(toIndex, -1,
                    "The line/pattern '" + to + "' until where the output should match can not be found");
        }

        List<String> subList = lines.subList(fromIndex, toIndex);
        int matchedCount = 0;
        for (String line : subList) {
            assertTrue(line.matches(pattern),
                    "The line '" + line + "' does not match pattern '" + pattern + "'");
            matchedCount++;
        }

        return matchedCount;
    }

}