package com.bayer.edam.migration;

import java.io.File;
import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Paths;
import java.util.ArrayList;
import java.util.HashSet;
import java.util.List;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.boot.CommandLineRunner;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.annotation.PropertySource;
import org.springframework.http.HttpEntity;
import org.springframework.http.HttpHeaders;
import org.springframework.http.HttpMethod;
import org.springframework.http.HttpStatus;
import org.springframework.http.ResponseEntity;
import org.springframework.web.client.HttpClientErrorException;
import org.springframework.web.client.RestTemplate;

import com.bayer.edam.migration.mam.Entry;
import com.bayer.edam.migration.mam.Entry.Download;
import com.bayer.edam.migration.mam.Entrylist;
import com.fasterxml.jackson.databind.ObjectMapper;

@SpringBootApplication
@PropertySource("file:secret.properties")
public class EntryDownloader implements CommandLineRunner {
	
	private static final Logger log = LoggerFactory.getLogger(EntryDownloader.class);
	
	@Value("${mam.auth}")
	private String mamAuth;

	
	static final String mamHost = "https://service.media-assistant.animalhealth.bayer.com";
	
	static final String separator = "|~|";

	
	private ObjectMapper jsonMapper = new ObjectMapper();
	private RestTemplate restTemplate = new RestTemplate();
	
	
	@Override
	public void run(String... strings) {
		HttpHeaders headers = new HttpHeaders();
		headers.add("Accept", "application/json");
		headers.add("Authorization", "Basic " + mamAuth);
		headers.add("Content-Type", "application/json");
		headers.add("From", "migration@bayer.com");
		HttpEntity<String> entity = new HttpEntity<String>("", headers);
		
		int lastPage = 1;
		for (int pageNum = 1; pageNum <= lastPage; pageNum++) {
			Entrylist entrylist = restTemplate.exchange(mamHost + "/rest/migration/entrylist?pagenumber={pagenum}&pagesize=500", HttpMethod.GET, entity, Entrylist.class, pageNum).getBody();
			lastPage = entrylist.lastPage;
			
			for (int i = 0; i < entrylist.entries.length; i++) {
				try {
					String entryJson = restTemplate.exchange(mamHost + "/rest/migration/entry/{id}", HttpMethod.GET, entity, String.class, entrylist.entries[i].mediaAssistantId).getBody();
					Entry entry = jsonMapper.readValue(entryJson, Entry.class);
					
					File targetDir = new File("E:\\" + entry.id);
					if (targetDir.exists()) {
						log.info("Skip " + entry.id + ", target directory already present");
						continue;
					}
					
					List<Download> downloadSelection = new ArrayList<Download>();
					
					// Select download: Download original only. If original is not available, download largest file
					Download selectedDownload = null;
					for (Download download : entry.downloadList) {
						if (download.entryFileVariation.equals("ORIGINAL")) {
							selectedDownload = download;
							break;
						}
						
						if (selectedDownload == null) {
							selectedDownload = download;
						}
						else if (selectedDownload.size < download.size) {
							selectedDownload = download;
						}
					}
					
					if (selectedDownload != null)
						downloadSelection.add(selectedDownload);
					
					// TODO extract, if zip --> postponed until upload
					
					for (Download download : entry.downloadListPublicFolder) {
						downloadSelection.add(download);
					}
					
					// clean download selection
					HashSet<String> hrefs = new HashSet<String>();
					List<Download> cleanedDownloads = new ArrayList<Download>();
					for (Download download : downloadSelection) {
						if (hrefs.add(download.href)) {
							cleanedDownloads.add(download);
						}
					}
					
					long aggregatedFilesize = 0;
					for (Download download : cleanedDownloads) {
						aggregatedFilesize += download.size;
					}
					
					log.info(entry.id + separator + entry.mediaAssistantId + separator + entry.stateId + separator + aggregatedFilesize + separator + entryJson);
					
					targetDir.mkdir();
					
					for (Download download : cleanedDownloads) {
						String filenameToUse;
						if (download.fileNameOnDisc != null)
							filenameToUse = download.fileNameOnDisc;
						else
							filenameToUse = download.fileName;
						
						try {
							ResponseEntity<byte[]> response = restTemplate.exchange(download.href, HttpMethod.GET, entity, byte[].class);
							
						    if (response.getStatusCode() == HttpStatus.OK) {
						        Files.write(Paths.get("E:\\" + entry.id + "\\" + filenameToUse), response.getBody());
						    }
						    else {
						    	log.error(entry.id + ", " + response.getStatusCodeValue() + ", " + download.href);
						    }
						}
						catch (HttpClientErrorException hcee) {
							log.error(hcee.getMessage());
							hcee.printStackTrace();
						}

					}
				}
				catch (IOException ioe) {
					log.error(ioe.getMessage());
					ioe.printStackTrace();
				}
			}
		}
	}

	public static void main(String args[]) {
		SpringApplication.run(EntryDownloader.class, args);
	}
	
}