/*

  *

  *

  */

 package com.damnhandy.uri.template;

 import com.damnhandy.uri.template.impl.Modifier;

 import com.damnhandy.uri.template.impl.Operator;

 import com.damnhandy.uri.template.impl.UriTemplateParser;

 import com.damnhandy.uri.template.impl.VarSpec;

 import org.joda.time.format.DateTimeFormat;

 import org.joda.time.format.DateTimeFormatter;

 import java.text.DateFormat;

 import java.text.SimpleDateFormat;

 import java.util.Collection;

 import java.util.LinkedList;

 import java.util.Map;

 /**

  * <p>

  * A utility class used for programatically generating a {@link UriTemplate}.

  * The class can be used as follows:

  * </p>

  * <pre>

  * UriTemplate template = UriTemplate.buildFromTemplate("http://example.com")

  *                                   .literal("/foo")

  *                                   .path(var("thing1"), var("explodedThing", true))

  *                                   .fragment(var("prefix", 2))

  *                                   .build();

  * </pre>

  * <p>

  * This code will return a {@link UriTemplate} with the following value:

  * </p>

  * <pre>

  * http://example.com/foo{/thing1,explodedThing*}{#prefix:2}

  * </pre>

  *

  * @author <a href="ryan@damnhandy.com">Ryan J. McDonough</a>

  * @version $Revision: 1.1 $

  */

 public final class UriTemplateBuilder

 {

     /**

      * The URI expression

      */

     private LinkedList<UriTemplateComponent> components = new LinkedList<UriTemplateComponent>();

     /**

      *

      */

     private DateTimeFormatter defaultDateTimeFormatter = null;

     /**

      *

      */

     private Map<String, Object> values = null;

     UriTemplateBuilder() {

         this.components = new LinkedList<UriTemplateComponent>();

     }

     /**

      * Create a new UriTemplateBuilder.

      *

      * @param templateString

      */

     UriTemplateBuilder(String templateString) throws MalformedUriTemplateException

     {

         this.components = new UriTemplateParser().scan(templateString);

     }

     /**

      * Create a new UriTemplateBuilder.

      *

      * @param template

      */

     UriTemplateBuilder(UriTemplate template) throws MalformedUriTemplateException

     {

         this(template.getTemplate());

         this.values = template.getValues();

         this.defaultDateTimeFormatter = template.defaultDateTimeFormatter;

     }

     /**

      * @param dateFormatString

      * @return

      * @since 2.0

      */

     public UriTemplateBuilder withDefaultDateFormat(String dateFormatString)

     {

         return this.withDefaultDateFormat(DateTimeFormat.forPattern(dateFormatString));

     }

     private UriTemplateBuilder withDefaultDateFormat(DateTimeFormatter dateTimeFormatter)

     {

         defaultDateTimeFormatter = dateTimeFormatter;

         return this;

     }

     /**

      * @param dateFormat

      * @return

      * @since 2.0

      * @deprecated replaced by {@link #withDefaultDateFormat(String) withDefaultDateFormat}

      */

     @Deprecated

     public UriTemplateBuilder withDefaultDateFormat(DateFormat dateFormat)

     {

         if (!(dateFormat instanceof SimpleDateFormat))

         {

             throw new IllegalArgumentException(

             "The only supported subclass of java.text.DateFormat is java.text.SimpleDateFormat");

         }

         defaultDateTimeFormatter = DateTimeFormat.forPattern(((SimpleDateFormat) dateFormat).toPattern());

         return this;

     }

     void addComponent(UriTemplateComponent component)

     {

         this.components.add(component);

     }

     void addComponents(Collection<UriTemplateComponent> compoments)

     {

         this.components.addAll(compoments);

     }

     /**

      * Appends a {@link Literal} value to the {@link UriTemplate}. The following

      * code:

      * <p>

      * <pre>

      * UriTemplate template = UriTemplate.buildFromTemplate("http://example.com")

      *                                   .literal("/foo")

      *                                   .build();

      * </pre>

      * <p>

      * Will generate the following template:

      * <p>

      * <pre>

      * http://example.com/foo

      * </pre>

      * <p>

      * Note that this particular example has no expressions, so it's not a valid URI template.

      *

      * @param string

      * @return

      */

     public UriTemplateBuilder literal(String string)

     {

         if (string == null)

         {

             return this;

         }

         addComponent(new Literal(string, 0));

         return this;

     }

     /**

      * @param varSpec

      * @return

      */

     private static VarSpec[] toVarSpec(String... varSpec)

     {

         VarSpec[] vars = new VarSpec[varSpec.length];

         for (int i = 0; i < varSpec.length; i++)

         {

             vars[i] = var(varSpec[i]);

         }

         return vars;

     }

     /**

      * Appends a template expression using no operator. The following

      * code:

      * <pre>

      * UriTemplate template =

      *        UriTemplate.buildFromTemplate("http://example.com/")

      *                   .simple("foo")

      *                   .build();

      * </pre>

      * Will generate the following URI Template string:

      * <pre>

      * http://example.com/{foo}

      * </pre>

      *

      * @param var

      * @return

      */

     public UriTemplateBuilder simple(String... var)

     {

         simple(toVarSpec(var));

         return this;

     }

     /**

      * Appends a template expression using no operator but with an optional

      * modifier. The following code:

      * <pre>

      * import static com.damnhandy.uri.template.UriTemplateBuilder.var;

      *

      * ...

      *

      * UriTemplate template =

      *        UriTemplate.buildFromTemplate("http://example.com/")

      *                   .simple(var("foo",true))

      *                   .build();

      * </pre>

      * Will generate the following URI Template string:

      * <pre>

      * http://example.com/{foo*}

      * </pre>

      *

      * @param var

      * @return

      */

     public UriTemplateBuilder simple(VarSpec... var)

     {

         addComponent(Expression.simple(var).build());

         return this;

     }

     /**

      * Appends a template expression using the reserved operator (+). The following

      * code:

      * <pre>

      * UriTemplate template =

      *        UriTemplate.buildFromTemplate("http://example.com/")

      *                   .reserved("foo")

      *                   .build();

      * </pre>

      * Will generate the following URI Template string:

      * <pre>

      * http://example.com/{+foo}

      * </pre>

      *

      * @param var

      * @return

      */

     public UriTemplateBuilder reserved(String... var)

     {

         reserved(toVarSpec(var));

         return this;

     }

     /**

      * Appends a template expression using the reserved operator (+) along

      * with an optional modifier. The following code:

      * <pre>

      * import static com.damnhandy.uri.template.UriTemplateBuilder.var;

      *

      * ...

      *

      * UriTemplate template =

      *        UriTemplate.buildFromTemplate("http://example.com/")

      *                   .reserved(var("foo",1))

      *                   .build();

      * </pre>

      * Will generate the following URI Template string:

      * <pre>

      * http://example.com/{+foo:1}

      * </pre>

      *

      * @param var

      * @return

      */

     public UriTemplateBuilder reserved(VarSpec... var)

     {

         addComponent(Expression.reserved(var).build());

         return this;

     }

     /**

      * Appends a template expression using the fragment operator (#). The

      * following code:

      * <pre>

      * UriTemplate template =

      *        UriTemplate.buildFromTemplate("http://example.com/")

      *                   .fragement("foo")

      *                   .build();

      * </pre>

      * Will generate the following URI Template string:

      * <pre>

      * http://example.com/{#foo}

      * </pre>

      *

      * @param var

      * @return

      * @throws UriTemplateBuilderException if you attempt to add more than one fragment expression, a UriTemplateBuilderException will be raised

      */

     public UriTemplateBuilder fragment(String... var) throws UriTemplateBuilderException

     {

         fragment(toVarSpec(var));

         return this;

     }

     /**

      * Appends a template expression using the fragment operator (#) with a

      * modifier. The following code:

      * <pre>

      * import static com.damnhandy.uri.template.UriTemplateBuilder.var;

      *

      * ...

      *

      * UriTemplate template =

      *        UriTemplate.buildFromTemplate("http://example.com/")

      *                   .fragement(var("foo", 1))

      *                   .build();

      * </pre>

      * Will generate the following URI Template string:

      * <pre>

      * http://example.com/{#foo:1}

      * </pre>

      *

      * @param var

      * @return

      * @throws UriTemplateBuilderException if you attempt to add more than one fragment expression, a UriTemplateBuilderException will be raised

      */

     public UriTemplateBuilder fragment(VarSpec... var) throws UriTemplateBuilderException

     {

         if (hasExpressionWithOperator(Operator.FRAGMENT))

         {

             throw new UriTemplateBuilderException("The template already has a fragment expression and this would not result in a valid URI");

         }

         addComponent(Expression.fragment(var).build());

         return this;

     }

     /**

      * Scans the components for an expression with the specified operator.

      *

      * @param op

      * @return

      */

     private boolean hasExpressionWithOperator(Operator op)

     {

         for (UriTemplateComponent c : components)

         {

             if (Expression.class.isInstance(c))

             {

                 Expression e = (Expression) c;

                 if (e.getOperator() == op)

                 {

                     return true;

                 }

             }

         }

         return false;

     }

     /**

      * Appends a template expression using the label (.) operator. The following

      * code:

      * <pre>

      * UriTemplate template =

      *        UriTemplate.buildFromTemplate("http://example.com/")

      *                   .label("foo")

      *                   .build();

      * </pre>

      * Will generate the following URI Template string:

      * <pre>

      * http://example.com/{.foo}

      * </pre>

      *

      * @param var

      * @return

      */

     public UriTemplateBuilder label(String... var)

     {

         label(toVarSpec(var));

         return this;

     }

     /**

      * Appends a template expression using the label (.) operator and modifier.

      * The following code:

      * <pre>

      * UriTemplate template =

      *        UriTemplate.buildFromTemplate("http://example.com/")

      *                   .label(var("foo", true))

      *                   .build();

      * </pre>

      * Will generate the following URI Template string:

      * <pre>

      * http://example.com/{.foo*}

      * </pre>

      *

      * @param var

      * @return

      */

     public UriTemplateBuilder label(VarSpec... var)

     {

         addComponent(Expression.label(var).build());

         return this;

     }

     /**

      * Appends a template expression using the matrix (;) operator. The following

      * code:

      * <pre>

      * UriTemplate template =

      *        UriTemplate.buildFromTemplate("http://example.com/")

      *                   .matrix("foo")

      *                   .build();

      * </pre>

      * Will generate the following URI Template string:

      * <pre>

      * http://example.com/{;foo}

      * </pre>

      *

      * @param var

      * @return

      */

     public UriTemplateBuilder matrix(String... var)

     {

         matrix(toVarSpec(var));

         return this;

     }

     /**

      * Appends a template expression using the matrix (;) operator and modifier.

      * The following code:

      * <pre>

      * UriTemplate template =

      *        UriTemplate.buildFromTemplate("http://example.com/")

      *                   .matrix(var("foo", true))

      *                   .build();

      * </pre>

      * Will generate the following URI Template string:

      * <pre>

      * http://example.com/{;foo*}

      * </pre>

      *

      * @param var

      * @return

      */

     public UriTemplateBuilder matrix(VarSpec... var)

     {

         addComponent(Expression.matrix(var).build());

         return this;

     }

     /**

      * Appends a template expression using the path (/) operator. The following

      * code:

      * <pre>

      * UriTemplate template =

      *        UriTemplate.buildFromTemplate("http://example.com")

      *                   .path("foo")

      *                   .build();

      * </pre>

      * Will generate the following URI Template string:

      * <pre>

      * http://example.com{/foo}

      * </pre>

      *

      * @param var

      * @return

      */

     public UriTemplateBuilder path(String... var)

     {

         path(toVarSpec(var));

         return this;

     }

     /**

      * Appends a template expression using the path (/) operator and modifier.

      * The following code:

      * <pre>

      * UriTemplate template =

      *        UriTemplate.buildFromTemplate("http://example.com")

      *                   .path(var("foo", 1))

      *                   .build();

      * </pre>

      * Will generate the following URI Template string:

      * <pre>

      * http://example.com{/foo:1}

      * </pre>

      *

      * @param var

      * @return

      */

     public UriTemplateBuilder path(VarSpec... var)

     {

         addComponent(Expression.path(var).build());

         return this;

     }

     /**

      * Appends a template expression using the query (?) operator. The following

      * code:

      * <pre>

      * UriTemplate template =

      *        UriTemplate.buildFromTemplate("http://example.com/")

      *                   .query("foo")

      *                   .build();

      * </pre>

      * Will generate the following URI Template string:

      * <pre>

      * http://example.com/{?foo}

      * </pre>

      *

      * @param var

      * @return

      */

     public UriTemplateBuilder query(String... var)

     {

         query(toVarSpec(var));

         return this;

     }

     /**

      * Appends a template expression using the query (?) operator and

      * and optional modifier. The following

      * code:

      * <pre>

      * import static com.damnhandy.uri.template.UriTemplateBuilder.var;

      *

      * ...

      *

      * UriTemplate template =

      *        UriTemplate.buildFromTemplate("http://example.com/")

      *                   .query(var("foo",1))

      *                   .build();

      * </pre>

      * Will generate the following URI Template string:

      * <pre>

      * http://example.com/{?foo:1}

      * </pre>

      *

      * @param var

      * @return

      */

     public UriTemplateBuilder query(VarSpec... var)

     {

         addComponent(Expression.query(var).build());

         return this;

     }

     /**

      * Appends a template expression using the form-style query continuation. The following

      * code:

      * <pre>

      * UriTemplate template =

      *        UriTemplate.buildFromTemplate("http://example.com/")

      *                   .continuation("foo")

      *                   .build();

      * </pre>

      * Will generate the following URI Template string:

      * <pre>

      * http://example.com/{&foo}

      * </pre>

      *

      * @param var

      * @return

      */

     public UriTemplateBuilder continuation(String... var)

     {

         return continuation(toVarSpec(var));

     }

     /**

      * Appends a template expression using the form-style query continuation and

      * and optional modifier. The following

      * code:

      * <pre>

      * import static com.damnhandy.uri.template.UriTemplateBuilder.var;

      *

      * ...

      *

      * UriTemplate template =

      *        UriTemplate.buildFromTemplate("http://example.com/")

      *                   .query(var("foo",1))

      *                   .build();

      * </pre>

      * Will generate the following URI Template string:

      * <pre>

      * http://example.com/{&foo:1}

      * </pre>

      *

      * @param var

      * @return

      */

     public UriTemplateBuilder continuation(VarSpec... var)

     {

         addComponent(Expression.continuation(var).build());

         return this;

     }

     /**

      * Parses the template and appends the parsed components

      * to the builder. The following

      * code:

      * <pre>

      * import static com.damnhandy.uri.template.UriTemplateBuilder.var;

      *

      * ...

      *

      * UriTemplate template =

      *        UriTemplate.buildFromTemplate("http://example.com/")

      *                   .template("foo/{id}{?filter}")

      *                   .build();

      * </pre>

      * Will generate the following URI Template string:

      * <pre>

      * http://example.com/foo/{id}{?filter}

      * </pre>

      *

      * @param template

      * @return

      */

     public UriTemplateBuilder template(UriTemplate... template) {

         for(UriTemplate t : template) {

             addComponents(t.getComponents());

         }

         return this;

     }

     /**

      * Parses the template and appends the parsed components

      * to the builder. The following

      * code:

      * <pre>

      * import static com.damnhandy.uri.template.UriTemplateBuilder.var;

      *

      * ...

      *

      * UriTemplate template =

      *        UriTemplate.buildFromTemplate("http://example.com/")

      *                   .template("foo/{id}{?filter}")

      *                   .build();

      * </pre>

      * Will generate the following URI Template string:

      * <pre>

      * http://example.com/foo/{id}{?filter}

      * </pre>

      *

      * @param template

      * @return

      */

     public UriTemplateBuilder template(String... template) {

         UriTemplateParser parser = new UriTemplateParser();

         for(String t : template) {

             addComponents(parser.scan(t));

         }

         return this;

     }

     /**

      * Returns an array of the components in the Builder.

      * @return

      */

     public UriTemplateComponent[] getComponents()

     {

         return this.components.toArray(new UriTemplateComponent[components.size()]);

     }

     /**

      * <p>

      * Generates a {@link UriTemplate} instance from the builder.

      * </p>

      *

      * @return the UriTemplate

      * @since 2.0

      */

     public UriTemplate build() throws MalformedUriTemplateException

     {

         UriTemplate template = new UriTemplate(this.components);

         if (this.values != null)

         {

             template.set(values);

         }

         if (defaultDateTimeFormatter != null)

         {

             template.defaultDateTimeFormatter = defaultDateTimeFormatter;

         }

         return template;

     }

     /**

      * Adds a variable name to the expression.

      * <p>

      * <pre>

      * var("foo");

      * </pre>

      * <p>

      * Will yield the following expression:

      * <pre>

      * {foo}

      * </pre>

      *

      * @param varName

      * @return the {@link com.damnhandy.uri.template.impl.VarSpec} for the specified name

      */

     public static VarSpec var(String varName)

     {

         return var(varName, Modifier.NONE, null);

     }

     /**

      * Adds a variable name to the expression with an explode modifier.

      * <p>

      * <pre>

      * var("foo",true);

      * </pre>

      * <p>

      * Will yield the following expression:

      * <pre>

      * {foo*}

      * </pre>

      *

      * @param varName

      * @param explode

      * @return the {@link com.damnhandy.uri.template.impl.VarSpec} for the specified name

      */

     public static VarSpec var(String varName, boolean explode)

     {

         if (explode)

         {

             return var(varName, Modifier.EXPLODE, null);

         }

         return var(varName, Modifier.NONE, null);

     }

     /**

      * Adds a variable name to the expression with a prefix modifier.

      * <p>

      * <pre>

      * var("foo",2);

      * </pre>

      * <p>

      * Will yield the following expression:

      * <pre>

      * {foo:2}

      * </pre>

      *

      * @param varName

      * @param prefix

      * @return the {@link com.damnhandy.uri.template.impl.VarSpec} for the specified name

      */

     public static VarSpec var(String varName, int prefix)

     {

         return var(varName, Modifier.PREFIX, prefix);

     }

     /**

      * @param varName

      * @param modifier

      * @param position

      * @return the {@link com.damnhandy.uri.template.impl.VarSpec} for the specified name

      */

     private static VarSpec var(String varName, Modifier modifier, Integer position)

     {

         return new VarSpec(varName, modifier, position);

     }

 }