/*
 * Copyright 2017-2020 original authors
 *
 * 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
 *
 * https://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 io.micronaut.http.client.multipart;

import io.micronaut.core.annotation.Internal;
import io.micronaut.http.MediaType;
import io.micronaut.http.multipart.MultipartException;
import java.io.File;
import java.io.InputStream;
import java.util.ArrayList;
import java.util.List;

A builder class to generate a list a list of parts for a multi part request.
Author:
James Kleeh, graemerocher
Since:
1.0/**
 * A builder class to generate a list a list of parts for a multi part request.
 *
 * @author James Kleeh
 * @author graemerocher
 * @since 1.0
 */
public final class MultipartBody {

    private final List<Part<?>> parts;

    
Initialize with all the parts.
Params:
parts – The List of all parts to be sent in the body of Netty multipart request, such a File, String, Bytes etc./**
     * Initialize with all the parts.
     *
     * @param parts The List of all parts to be sent in the body of Netty multipart request, such a File, String, Bytes etc.
     */
    private MultipartBody(List<Part<?>> parts) {
        this.parts = parts;
    }

    
Create a list of data objects using the given factory.
Params:
factory – The factory used to create the data objects.
Type parameters:
<T> – The data type
Returns:
List of data objects/**
     * Create a list of data objects using the given factory.
     *
     * @param factory The factory used to create the data objects.
     * @return List of data objects
     * @param <T> The data type
     */
    @Internal
    public <T> List<T> getData(MultipartDataFactory<T> factory) {
        List<T> data = new ArrayList<>(parts.size());
        for (Part<?> part : parts) {
            data.add(part.getData(factory));
        }
        return data;
    }

    
Returns:
A Builder to build MultipartBody./**
     * @return A Builder to build MultipartBody.
     */
    public static Builder builder() {
        return new Builder();
    }

    
A builder class to add different Part to MultipartBody. /**
     * A builder class to add different {@link Part} to {@link MultipartBody}.
     */
    public static final class Builder {

        
List of all parts.
/**
         * List of all parts.
         */
        private List<Part<?>> parts = new ArrayList<>();

        
Construct a builder.
/**
         * Construct a builder.
         */
        private Builder() {
        }

        
Add a file object to MultipartBody.
Params:
name – Name of the parameter for file object to be passed in multipart request
file – The file object to copy the content to FileUpload
Returns:
A Builder to build MultipartBody/**
         * Add a file object to MultipartBody.
         *
         * @param name Name of the parameter for file object to be passed in multipart request
         * @param file The file object to copy the content to {@link io.micronaut.http.multipart.FileUpload}
         * @return A {@link MultipartBody.Builder} to build MultipartBody
         */
        public Builder addPart(String name, File file) {
            return addPart(name, file.getName(), file);
        }

        
Add a file object to MultipartBody.
Params:
name –     Name of the parameter for file object to be passed in multipart request
filename – Name of the file
file –  The file object to copy the content to FileUpload
Returns:
A Builder to build MultipartBody/**
         * Add a file object to MultipartBody.
         *
         * @param name     Name of the parameter for file object to be passed in multipart request
         * @param filename Name of the file
         * @param file     The file object to copy the content to {@link io.micronaut.http.multipart.FileUpload}
         * @return A {@link MultipartBody.Builder} to build MultipartBody
         */
        public Builder addPart(String name, String filename, File file) {
            return addFilePart(new FilePart(name, filename, file));
        }

        
Add a file object to MultipartBody.
Params:
name –        Name of the parameter for file object to be passed in multipart request
filename –    Name of the file
contentType – File content of type MediaType, possible values could be "text/plain", "application/json" etc
file –  The file object to copy the content to FileUpload
Returns:
A Builder to build MultipartBody/**
         * Add a file object to MultipartBody.
         *
         * @param name        Name of the parameter for file object to be passed in multipart request
         * @param filename    Name of the file
         * @param contentType File content of type {@link MediaType}, possible values could be "text/plain", "application/json" etc
         * @param file        The file object to copy the content to {@link io.micronaut.http.multipart.FileUpload}
         * @return A {@link MultipartBody.Builder} to build MultipartBody
         */
        public Builder addPart(String name, String filename, MediaType contentType, File file) {
            return addFilePart(new FilePart(name, filename, contentType, file));
        }

        
Add bytes data to MultipartBody.
Params:
name –     Name of the parameter for file object to be passed in multipart request
filename – Name of the file
data –     A byte Array (byte[]) representing the contents of the file
Returns:
A Builder to build MultipartBody/**
         * Add bytes data to MultipartBody.
         *
         * @param name     Name of the parameter for file object to be passed in multipart request
         * @param filename Name of the file
         * @param data     A byte Array (byte[]) representing the contents of the file
         * @return A {@link MultipartBody.Builder} to build MultipartBody
         */
        public Builder addPart(String name, String filename, byte[] data) {
            return addFilePart(new BytePart(name, filename, data));
        }

        
Add bytes data to MultipartBody.
Params:
name –        Name of the parameter for file object to be passed in multipart request
filename –    Name of the file
contentType – The content type of File, possible values could be "text/plain", "application/json" etc
data –        A byte Array (byte[]) representing the contents of the file
Returns:
A Builder to build MultipartBody/**
         * Add bytes data to MultipartBody.
         *
         * @param name        Name of the parameter for file object to be passed in multipart request
         * @param filename    Name of the file
         * @param contentType The content type of File, possible values could be "text/plain", "application/json" etc
         * @param data        A byte Array (byte[]) representing the contents of the file
         * @return A {@link MultipartBody.Builder} to build MultipartBody
         */
        public Builder addPart(String name, String filename, MediaType contentType, byte[] data) {
            return addFilePart(new BytePart(name, filename, contentType, data));
        }

        
Add a InputStream data to MultipartBody.
Params:
name –          Name of the parameter for file object to be passed in multipart request
filename –      Name of the file
data –  An InputStream data value representing the content of file object
contentLength – The size of the content
Returns:
A Builder to build MultipartBody/**
         * Add a InputStream data to MultipartBody.
         *
         * @param name          Name of the parameter for file object to be passed in multipart request
         * @param filename      Name of the file
         * @param data          An {@link InputStream} data value representing the content of file object
         * @param contentLength The size of the content
         * @return A {@link MultipartBody.Builder} to build MultipartBody
         */
        public Builder addPart(String name, String filename, InputStream data, long contentLength) {
            return addFilePart(new InputStreamPart(name, filename, data, contentLength));
        }

        
Add a InputStream data to MultipartBody.
Params:
name –          Name of the parameter for file object to be passed in multipart request
filename –      Name of the file
contentType –   The content type of File, possible values could be "text/plain", "application/json" etc
data –  An InputStream data value representing the content of file object
contentLength – The size of the content
Returns:
A Builder to build MultipartBody/**
         * Add a InputStream data to MultipartBody.
         *
         * @param name          Name of the parameter for file object to be passed in multipart request
         * @param filename      Name of the file
         * @param contentType   The content type of File, possible values could be "text/plain", "application/json" etc
         * @param data          An {@link InputStream} data value representing the content of file object
         * @param contentLength The size of the content
         * @return A {@link MultipartBody.Builder} to build MultipartBody
         */
        public Builder addPart(String name, String filename, MediaType contentType, InputStream data, long contentLength) {
            return addFilePart(new InputStreamPart(name, filename, contentType, data, contentLength));
        }

        
Add a file object to MultipartBody.
Params:
name –  Name of the parameter or the key to be passed in multipart request
value – Plain String value for the parameter
Returns:
A Builder to build MultipartBody/**
         * Add a file object to MultipartBody.
         *
         * @param name  Name of the parameter or the key to be passed in multipart request
         * @param value Plain String value for the parameter
         * @return A {@link MultipartBody.Builder} to build MultipartBody
         */
        public Builder addPart(String name, String value) {
            parts.add(new StringPart(name, value));
            return this;
        }

        
This method is used for adding different parts extending AbstractFilePart class to MultipartBody. 
Params:
filePart – Any file part, such as FilePart, InputStreamPart, BytePart etc
Returns:
A Builder to build MultipartBody/**
         * This method is used for adding different parts extending {@link AbstractFilePart} class to
         * {@link MultipartBody}.
         *
         * @param filePart Any file part, such as {@link FilePart}, {@link InputStreamPart}, {@link BytePart} etc
         * @return A {@link MultipartBody.Builder} to build MultipartBody
         */
        private Builder addFilePart(AbstractFilePart filePart) {
            parts.add(filePart);
            return this;
        }

        
Creates MultipartBody from the provided parts. 
Throws:
MultipartException – If there are no parts
Returns:
The MultipartBody/**
         * Creates {@link MultipartBody} from the provided parts.
         *
         * @return The {@link MultipartBody}
         * @throws MultipartException If there are no parts
         */
        public MultipartBody build() throws MultipartException {
            if (parts.isEmpty()) {
                throw new MultipartException("Cannot create a MultipartBody with no parts");
            }
            return new MultipartBody(parts);
        }
    }
}