/*******************************************************************************
 * Copyright (c) 2000, 2007 IBM Corporation and others.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     IBM Corporation - initial API and implementation
 * Port to the D programming language:
 *     Frank Benoit <benoit@tionex.de>
 *******************************************************************************/
module dwtx.jface.text.templates.TemplateVariable;

import dwtx.jface.text.templates.SimpleTemplateVariableResolver; // packageimport
import dwtx.jface.text.templates.TemplateBuffer; // packageimport
import dwtx.jface.text.templates.TemplateContext; // packageimport
import dwtx.jface.text.templates.TemplateContextType; // packageimport
import dwtx.jface.text.templates.Template; // packageimport
import dwtx.jface.text.templates.PositionBasedCompletionProposal; // packageimport
import dwtx.jface.text.templates.TemplateException; // packageimport
import dwtx.jface.text.templates.TemplateTranslator; // packageimport
import dwtx.jface.text.templates.DocumentTemplateContext; // packageimport
import dwtx.jface.text.templates.GlobalTemplateVariables; // packageimport
import dwtx.jface.text.templates.InclusivePositionUpdater; // packageimport
import dwtx.jface.text.templates.TemplateProposal; // packageimport
import dwtx.jface.text.templates.ContextTypeRegistry; // packageimport
import dwtx.jface.text.templates.JFaceTextTemplateMessages; // packageimport
import dwtx.jface.text.templates.TemplateCompletionProcessor; // packageimport
import dwtx.jface.text.templates.TextTemplateMessages; // packageimport
import dwtx.jface.text.templates.TemplateVariableType; // packageimport
import dwtx.jface.text.templates.TemplateVariableResolver; // packageimport


import dwt.dwthelper.utils;


import dwtx.core.runtime.Assert;
import dwtx.jface.text.TextUtilities;

/**
 * A <code>TemplateVariable</code> represents a set of positions into a
 * <code>TemplateBuffer</code> with identical content each. <code>TemplateVariableResolver</code>s
 * can be used to resolve a template variable to a symbol available from the
 * <code>TemplateContext</code>. A resolved variable may have one or more possible
 * {@link #getValues() values} which may be presented to the user as choices. If there is no user
 * interaction the {@link #getDefaultValue() default value} is chosen as textual representation of
 * the variable.
 * <p>
 * Clients may instantiate and extend this class.
 * </p>
 *
 * @see TemplateVariableResolver
 * @see TemplateBuffer
 * @since 3.0
 */
public class TemplateVariable {

    /** The type name of the variable */
    private final TemplateVariableType fType;
    /** The name of the variable. */
    private final String fName;
    /** The initial length in the template pattern. */
    private final int fInitialLength;
    /** The offsets of the variable. */
    private int[] fOffsets;
    /** Flag indicating if the variable has been resolved unambiguously. */
    private bool fIsUnambiguous;
    /** Flag indicating if the variable has been resolved by a resolver. */
    private bool fIsResolved;
    /**
     * The proposal strings available for this variable. The first string is
     * the default value.
     */
    private String[] fValues;

    /**
     * Creates a template variable. The type is used as the name of the
     * variable.
     *
     * @param type the type of the variable
     * @param defaultValue the default value of the variable
     * @param offsets the array of offsets of the variable
     */
    public this(String type, String defaultValue, int[] offsets) {
        this(type, [ defaultValue ], offsets);
    }

    /**
     * Creates a template variable.
     *
     * @param type the type of the variable
     * @param name the name of the variable
     * @param defaultValue the default value of the variable
     * @param offsets the array of offsets of the variable
     */
    public this(String type, String name, String defaultValue, int[] offsets) {
        this(type, name, [ defaultValue ], offsets);
    }

    /**
     * Creates a template variable.
     *
     * @param type the type of the variable
     * @param name the name of the variable
     * @param defaultValue the default value of the variable
     * @param offsets the array of offsets of the variable
     * @since 3.3
     */
    public this(TemplateVariableType type, String name, String defaultValue, int[] offsets) {
        this(type, name, [ defaultValue ], offsets);
    }

    /**
     * Creates a template variable with multiple possible values. The type is
     * used as the name of the template.
     *
     * @param type the type of the template variable
     * @param values the values available at this variable, non-empty
     * @param offsets the array of offsets of the variable
     */
    public this(String type, String[] values, int[] offsets) {
        this(type, type, values, offsets);
    }

    /**
     * Creates a template variable with multiple possible values.
     *
     * @param type the type of the variable
     * @param name the name of the variable
     * @param values the values available at this variable, non-empty
     * @param offsets the array of offsets of the variable
     */
    public this(String type, String name, String[] values, int[] offsets) {
        this(new TemplateVariableType(type), name, values, offsets);
    }

    /**
     * Creates a template variable with multiple possible values.
     *
     * @param type the type of the variable
     * @param name the name of the variable
     * @param values the values available at this variable, non-empty
     * @param offsets the array of offsets of the variable
     * @since 3.3
     */
    this(TemplateVariableType type, String name, String[] values, int[] offsets) {
        Assert.isNotNull(type);
        Assert.isNotNull(name);
        fType= type;
        fName= name;
        setValues(values);
        setOffsets(offsets);
        setUnambiguous(false);
        setResolved(false);
        fInitialLength= values[0].length();
    }

    /**
     * Returns the type name of the variable.
     *
     * @return the type name of the variable
     */
    public String getType() {
        return fType.getName();
    }

    /**
     * Returns the type of the variable.
     *
     * @return the type of the variable
     * @since 3.3
     */
    public TemplateVariableType getVariableType() {
        return fType;
    }

    /**
     * Returns the name of the variable.
     *
     * @return the name of the variable
     */
    public String getName() {
        return fName;
    }

    /**
     * Returns the default value of the variable. Typically, this is the first of
     * the possible values (see {@link #getValues()}.
     *
     * @return the default value of the variable
     */
    public String getDefaultValue() {
        return getValues()[0];
    }

    /**
     * Returns the possible values for this variable. The returned array is owned by this variable
     * and must not be modified. The array is not empty.
     *
     * @return the possible values for this variable
     */
    public String[] getValues() {
        return fValues;
    }

    /**
     * Returns the length of the variable's default value.
     *
     * @return the length of the variable
     */
    public int getLength() {
        return getDefaultValue().length();
    }

    /**
     * Returns the initial length of the variable. The initial length is the lenght as it occurred
     * in the template pattern and is used when resolving a template to update the pattern with the
     * resolved values of the variable.
     *
     * @return the initial length of the variable
     * @since 3.3
     */
    final int getInitialLength() {
        return fInitialLength;
    }

    /**
     * Sets the offsets of the variable.
     *
     * @param offsets the new offsets of the variable
     */
    public void setOffsets(int[] offsets) {
        fOffsets= TextUtilities.copy(offsets);
    }

    /**
     * Returns the offsets of the variable. The returned array is
     * owned by this variable and must not be modified.
     *
     * @return the length of the variable
     */
    public int[] getOffsets() {
        return fOffsets;
    }

    /**
     * Resolves the variable to a single value. This is a shortcut for
     * <code>setValues(new String[] { value })</code>.
     *
     * @param value the new default value
     */
    public final void setValue(String value) {
        setValues([ value ]);
    }

    /**
     * Resolves the variable to several possible values for this variable, with the first being the
     * default value.
     *
     * @param values a non-empty array of values
     */
    public void setValues(String[] values) {
        Assert.isTrue(values.length > 0);
        fValues= TextUtilities.copy(values);
        setResolved(true);
    }

    /**
     * Sets the <em>isUnambiguous</em> flag of the variable.
     *
     * @param unambiguous the new unambiguous state of the variable
     */
    public void setUnambiguous(bool unambiguous) {
        fIsUnambiguous= unambiguous;
        if (unambiguous)
            setResolved(true);
    }

    /**
     * Returns <code>true</code> if the variable is unambiguously resolved, <code>false</code> otherwise.
     *
     * @return <code>true</code> if the variable is unambiguously resolved, <code>false</code> otherwise
     */
    public bool isUnambiguous() {
        return fIsUnambiguous;
    }

    /**
     * Sets the <em>resolved</em> flag of the variable.
     *
     * @param resolved the new <em>resolved</em> state
     * @since 3.3
     */
    public void setResolved(bool resolved) {
        fIsResolved= resolved;
    }

    /**
     * Returns <code>true</code> if the variable has been resolved, <code>false</code>
     * otherwise.
     *
     * @return <code>true</code> if the variable has been resolved, <code>false</code> otherwise
     * @since 3.3
     */
    public bool isResolved() {
        return fIsResolved;
    }
}