/*
  This file is licensed to You 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 org.xmlunit.assertj3;

import org.assertj.core.api.AbstractBooleanAssert;
import org.assertj.core.api.AbstractCharSequenceAssert;
import org.assertj.core.api.AbstractDoubleAssert;
import org.assertj.core.api.AbstractIntegerAssert;
import org.w3c.dom.Node;
import org.xmlunit.xpath.XPathEngine;

import static org.xmlunit.assertj3.AssertionsAdapter.withAssertInfo;
import static org.xmlunit.assertj3.error.ShouldBeConvertible.shouldBeConvertible;

/**
 * Assertion methods for {@link String} result of XPath evaluation.
 *
 * <p><b>Simple Example</b></p>
 *
 * <pre>
 * import static org.xmlunit.assertj.XmlAssert.assertThat;
 *
 * final String xml = &quot;&lt;a&gt;&lt;b attr=\&quot;abc\&quot;&gt;&lt;/b&gt;&lt;/a&gt;&quot;;
 *
 * assertThat(xml).valueByXPath("count(//a/b)").isEqualTo(3);
 * </pre>
 *
 * @since XMLUnit 2.8.1
 */
public class ValueAssert extends AbstractCharSequenceAssert<ValueAssert, String> {

    private ValueAssert(String value) {
        super(value, ValueAssert.class);
    }

    static ValueAssert create(Object xmlSource, String xPath, XmlAssertConfig config) {
        AssertionsAdapter.assertThat(xPath, config.info).isNotBlank();

        final XPathEngine engine = XPathEngineFactory.create(config);
        Node root = NodeUtils.parseSource(xmlSource, config);
        String value = engine.evaluate(xPath, root);

        ValueAssert valueAssert = withAssertInfo(new ValueAssert(value), config.info);
        if (!valueAssert.info.hasDescription()) {
            valueAssert.info.description("XPath \"%s\" evaluated to value", xPath);
        }

        return valueAssert;
    }

    /**
     * Returns an {@code Assert} object that allows performing assertions on integer value of the {@link String} under test.
     *
     * @throws AssertionError if the actual value is {@code null}.
     * @throws AssertionError if the actual value does not contain a parsable integer
     * @return an {@code Assert} object for integer assertions
     */
    public AbstractIntegerAssert<?> asInt() {
        isNotNull();
        int value = 0;
        try {
            value = Integer.parseInt(actual);
        } catch (NumberFormatException e) {
            throwAssertionError(shouldBeConvertible(actual, "int"));
        }

        return AssertionsAdapter.assertThat(value, info);
    }

    /**
     * Returns an {@code Assert} object that allows performing assertions on integer value of the {@link String} under test.
     *
     * @throws AssertionError if the actual value is {@code null}.
     * @throws AssertionError if the actual value does not contain a parsable double
     * @return an {@code Assert} object for double assertions
     */
    public AbstractDoubleAssert<?> asDouble() {
        isNotNull();
        double value = 0;
        try {
            value = Double.parseDouble(actual);
        } catch (NumberFormatException e) {
            throwAssertionError(shouldBeConvertible(actual, "double"));
        }

        return AssertionsAdapter.assertThat(value, info);
    }

    /**
     * Returns an {@code Assert} object that allows performing assertions on boolean value of the {@link String} under test.
     * <p>
     * If actual value after lowercasing is one of the following "true", "false", then it can be parsed to boolean.
     *
     * @throws AssertionError if the actual value is {@code null}.
     * @throws AssertionError if the actual value does not contain a parsable boolean
     * @return an {@code Assert} object for boolean assertions
     */
    public AbstractBooleanAssert<?> asBoolean() {
        isNotNull();
        boolean value = false;
        switch (actual.toLowerCase()) {
            case "true":
                value = true;
                break;
            case "false":
                value = false;
                break;
            default:
                throwAssertionError(shouldBeConvertible(actual, "boolean"));
        }

        return AssertionsAdapter.assertThat(value, info);
    }

    /**
     * Returns an {@code XmlAssert} object that allows performing assertions on XML value of the {@link String} under test.
     *
     * @throws AssertionError if the actual value is {@code null}.
     * @return an {@code Assert} object for XML assertions
     */
    public XmlAssert asXml() {
        isNotNull();
        return asXml(null);
    }

    /**
     * Returns an {@code XmlAssert} object that allows performing assertions on XML value of the {@link String} under test
     * wrapping around tag with name given in <b>wrapNodeName</b>.
     * If wrapNodeName is null or empty then wrapping is not applied.
     * <p>
     * Pseudocode:
     * <pre>
     *
     *  // given
     *  wrapNodeName = "ul";
     *  actual = "%lt;li&gt;a&lt;/li&gt;&lt;li&gt;&lt;/li&gt;";
     *
     *  // then
     *  xml = "&lt;ul&gt;&lt;li&gt;a&lt;/li&gt;&lt;li&gt;&lt;/li&gt;&lt;/ul&gt;";
     *  return XmlAssert.assertThat(xml);
     * </pre>
     *
     * @throws AssertionError if the actual value is {@code null}.
     * @return an {@code Assert} object for XML assertions
     * @param wrapNodeName name of the element to wrap around the string under test
     * @since XMLUnit 2.6.4
     */
    public XmlAssert asXml(String wrapNodeName) {
        isNotNull();
        final String xml;
        if (wrapNodeName == null || wrapNodeName.isEmpty()) {
            xml = actual;
        } else {
            xml = String.format("<%s>%s</%s>", wrapNodeName, actual, wrapNodeName);
        }

        return withAssertInfo(XmlAssert.assertThat(xml), info);
    }

    /**
     * Try convert the {@link String} under test to int using {@link #asInt()} and compare with given value.
     * @param expected expected value
     * @return this
     */
    public ValueAssert isEqualTo(int expected) {
        asInt().isEqualTo(expected);

        return this;
    }

    /**
     * Try convert the {@link String} under test to double using {@link #asDouble()} and compare with given value.
     * @param expected expected value
     * @return this
     */
    public ValueAssert isEqualTo(double expected) {
        asDouble().isEqualTo(expected);

        return this;
    }

    /**
     * Try convert the {@link String} under test to boolean using {@link #asBoolean()} and compare with given value.
     * @param expected expected value
     * @return this
     */
    public ValueAssert isEqualTo(boolean expected) {
        asBoolean().isEqualTo(expected);

        return this;
    }

}
