package com.box.sdk;

import com.eclipsesource.json.Json;
import com.eclipsesource.json.JsonArray;
import com.eclipsesource.json.JsonObject;
import com.eclipsesource.json.JsonValue;
import java.net.URL;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;

/**
 * Represents a retention policy assignment.
 *
 * <p>Unless otherwise noted, the methods in this class can throw an unchecked {@link
 * BoxAPIException} (unchecked meaning that the compiler won't force you to handle it) if an error
 * occurs. If you wish to implement custom error handling for errors related to the Box REST API,
 * you should capture this exception explicitly.
 */
@BoxResourceType("retention_policy_assignment")
public class BoxRetentionPolicyAssignment extends BoxResource {

  /** Type for folder policy assignment. */
  public static final String TYPE_FOLDER = "folder";

  /** Type for enterprise policy assignment. */
  public static final String TYPE_ENTERPRISE = "enterprise";

  /** Type for metadata policy assignment. */
  public static final String TYPE_METADATA = "metadata_template";

  /** The URL template used for operation with retention policy assignments. */
  public static final URLTemplate ASSIGNMENTS_URL_TEMPLATE =
      new URLTemplate("retention_policy_assignments");

  /** The URL template used for operation with retention policy assignment with given ID. */
  public static final URLTemplate RETENTION_POLICY_ASSIGNMENT_URL_TEMPLATE =
      new URLTemplate("retention_policy_assignments/%s");

  /**
   * The URL template used for operation with files under retention with given retention policy
   * assignment ID.
   */
  public static final URLTemplate FILES_UNDER_RETENTION_URL_TEMPLATE =
      new URLTemplate("retention_policy_assignments/%s/files_under_retention");

  /**
   * The URL template used for operation with file versions under retention with given retention
   * policy assignment ID.
   */
  public static final URLTemplate FILE_VERSIONS_UNDER_RETENTION_URL_TEMPLATE =
      new URLTemplate("retention_policy_assignments/%s/file_versions_under_retention");

  private static final int DEFAULT_LIMIT = 100;

  /**
   * Constructs a BoxResource for a resource with a given ID.
   *
   * @param api the API connection to be used by the resource.
   * @param id the ID of the resource.
   */
  public BoxRetentionPolicyAssignment(BoxAPIConnection api, String id) {
    super(api, id);
  }

  /**
   * Assigns retention policy with givenID to the enterprise.
   *
   * @param api the API connection to be used by the created assignment.
   * @param policyID id of the assigned retention policy.
   * @return info about created assignment.
   */
  public static BoxRetentionPolicyAssignment.Info createAssignmentToEnterprise(
      BoxAPIConnection api, String policyID) {
    return createAssignment(
        api, policyID, new JsonObject().add("type", TYPE_ENTERPRISE), null, null);
  }

  /**
   * Assigns retention policy with givenID to the folder.
   *
   * @param api the API connection to be used by the created assignment.
   * @param policyID id of the assigned retention policy.
   * @param folderID id of the folder to assign policy to.
   * @return info about created assignment.
   */
  public static BoxRetentionPolicyAssignment.Info createAssignmentToFolder(
      BoxAPIConnection api, String policyID, String folderID) {
    return createAssignment(
        api, policyID, new JsonObject().add("type", TYPE_FOLDER).add("id", folderID), null, null);
  }

  /**
   * Assigns a retention policy to all items with a given metadata template, optionally matching on
   * fields.
   *
   * @param api the API connection to be used by the created assignment.
   * @param policyID id of the assigned retention policy.
   * @param templateID the ID of the metadata template to assign the policy to.
   * @param filter optional fields to match against in the metadata template.
   * @return info about the created assignment.
   */
  public static BoxRetentionPolicyAssignment.Info createAssignmentToMetadata(
      BoxAPIConnection api, String policyID, String templateID, MetadataFieldFilter... filter) {
    return createAssignmentToMetadata(api, policyID, templateID, null, filter);
  }

  /**
   * Assigns a retention policy to all items with a given metadata template, optionally matching on
   * fields.
   *
   * @param api the API connection to be used by the created assignment.
   * @param policyID id of the assigned retention policy.
   * @param templateID the ID of the metadata template to assign the policy to.
   * @param startDateField The date the retention policy assignment begins. This field can be a date
   *     field's metadata attribute key id.
   * @param filter optional fields to match against in the metadata template.
   * @return info about the created assignment.
   */
  public static BoxRetentionPolicyAssignment.Info createAssignmentToMetadata(
      BoxAPIConnection api,
      String policyID,
      String templateID,
      String startDateField,
      MetadataFieldFilter... filter) {
    JsonObject assignTo = new JsonObject().add("type", TYPE_METADATA).add("id", templateID);
    JsonArray filters = null;
    if (filter.length > 0) {
      filters = new JsonArray();
      for (MetadataFieldFilter f : filter) {
        filters.add(f.getJsonObject());
      }
    }
    return createAssignment(api, policyID, assignTo, startDateField, filters);
  }

  /**
   * Assigns retention policy with givenID to folder or enterprise.
   *
   * @param api the API connection to be used by the created assignment.
   * @param policyID id of the assigned retention policy.
   * @param assignTo object representing folder or enterprise to assign policy to.
   * @param filter Filters
   * @return info about created assignment.
   */
  private static BoxRetentionPolicyAssignment.Info createAssignment(
      BoxAPIConnection api,
      String policyID,
      JsonObject assignTo,
      String startDateField,
      JsonArray filter) {
    URL url = ASSIGNMENTS_URL_TEMPLATE.build(api.getBaseURL());
    BoxJSONRequest request = new BoxJSONRequest(api, url, "POST");

    JsonObject requestJSON = new JsonObject().add("policy_id", policyID).add("assign_to", assignTo);

    if (filter != null) {
      requestJSON.add("filter_fields", filter);
    }
    if (startDateField != null) {
      requestJSON.add("start_date_field", startDateField);
    }

    request.setBody(requestJSON.toString());
    try (BoxJSONResponse response = request.send()) {
      JsonObject responseJSON = Json.parse(response.getJSON()).asObject();
      BoxRetentionPolicyAssignment createdAssignment =
          new BoxRetentionPolicyAssignment(api, responseJSON.get("id").asString());
      return createdAssignment.new Info(responseJSON);
    }
  }

  /**
   * @param fields the fields to retrieve.
   * @return information about this retention policy assignment.
   */
  public BoxRetentionPolicyAssignment.Info getInfo(String... fields) {
    QueryStringBuilder builder = new QueryStringBuilder();
    if (fields.length > 0) {
      builder.appendParam("fields", fields);
    }
    URL url =
        RETENTION_POLICY_ASSIGNMENT_URL_TEMPLATE.buildWithQuery(
            this.getAPI().getBaseURL(), builder.toString(), this.getID());
    BoxJSONRequest request = new BoxJSONRequest(this.getAPI(), url, "GET");
    try (BoxJSONResponse response = request.send()) {
      JsonObject responseJSON = Json.parse(response.getJSON()).asObject();
      return new Info(responseJSON);
    }
  }

  /**
   * Retrieves all files under retention for assignment as Iterable. Default limit is 100
   *
   * @param fields the fields to retrieve.
   * @return an iterable contains information about all files under retentions as Iterable.
   */
  public Iterable<BoxFile.Info> getFilesUnderRetention(String... fields) {
    return this.getFilesUnderRetention(DEFAULT_LIMIT, fields);
  }

  /**
   * Retrieves all files under retention for assignment as Iterable.
   *
   * @param limit the limit of retrieved entries per page.
   * @param fields the fields to retrieve.
   * @return an iterable contains information about all files under retentions as Iterable.
   */
  public Iterable<BoxFile.Info> getFilesUnderRetention(int limit, String... fields) {
    QueryStringBuilder queryString = new QueryStringBuilder();
    if (fields.length > 0) {
      queryString.appendParam("fields", fields);
    }
    URL url =
        FILES_UNDER_RETENTION_URL_TEMPLATE.buildWithQuery(
            getAPI().getBaseURL(), queryString.toString(), getID());
    return new BoxResourceIterable<BoxFile.Info>(getAPI(), url, limit) {
      @Override
      protected BoxFile.Info factory(JsonObject jsonObject) {
        BoxFile boxFile = new BoxFile(getAPI(), jsonObject.get("id").asString());
        return boxFile.new Info(jsonObject);
      }
    };
  }

  /**
   * Retrieves all file version under retention for assignment as Iterable. Default limit is 100.
   *
   * @param fields the fields to retrieve.
   * @return an iterable contains information about all file versions under retentions as Iterable.
   */
  public Iterable<BoxFile.Info> getFileVersionsUnderRetention(String... fields) {
    return this.getFileVersionsUnderRetention(DEFAULT_LIMIT, fields);
  }

  /**
   * Retrieves all file version under retention for assignment as Iterable.
   *
   * @param limit the limit of retrieved entries per page.
   * @param fields the fields to retrieve.
   * @return an iterable contains information about all file versions under retentions as Iterable.
   */
  public Iterable<BoxFile.Info> getFileVersionsUnderRetention(int limit, String... fields) {
    QueryStringBuilder queryString = new QueryStringBuilder();
    if (fields.length > 0) {
      queryString.appendParam("fields", fields);
    }
    URL url =
        FILE_VERSIONS_UNDER_RETENTION_URL_TEMPLATE.buildWithQuery(
            getAPI().getBaseURL(), queryString.toString(), getID());
    return new BoxResourceIterable<BoxFile.Info>(getAPI(), url, limit) {
      @Override
      protected BoxFile.Info factory(JsonObject jsonObject) {
        BoxFile boxFile = new BoxFile(getAPI(), jsonObject.get("id").asString());
        return boxFile.new Info(jsonObject);
      }
    };
  }

  /** Deletes retention policy assignment. */
  public void delete() {
    URL url =
        RETENTION_POLICY_ASSIGNMENT_URL_TEMPLATE.build(this.getAPI().getBaseURL(), this.getID());
    BoxAPIRequest request = new BoxAPIRequest(this.getAPI(), url, "DELETE");
    request.send().close();
  }

  /** Contains information about the retention policy. */
  public class Info extends BoxResource.Info {

    /** @see #getRetentionPolicy() */
    private BoxRetentionPolicy.Info retentionPolicy;

    /** @see #getAssignedBy() */
    private BoxUser.Info assignedBy;

    /** @see #getAssignedAt() */
    private Date assignedAt;

    /** @see #getAssignedToType() */
    private String assignedToType;

    /** @see #getAssignedToID() */
    private String assignedToID;

    /** @see #getStartDateField() */
    private String startDateField;

    private List<MetadataFieldFilter> filterFields;

    /** Constructs an empty Info object. */
    public Info() {
      super();
    }

    /**
     * Constructs an Info object by parsing information from a JSON string.
     *
     * @param json the JSON string to parse.
     */
    public Info(String json) {
      super(json);
    }

    /**
     * Constructs an Info object using an already parsed JSON object.
     *
     * @param jsonObject the parsed JSON object.
     */
    Info(JsonObject jsonObject) {
      super(jsonObject);
    }

    /** {@inheritDoc} */
    @Override
    public BoxResource getResource() {
      return BoxRetentionPolicyAssignment.this;
    }

    /** @return the retention policy that has been assigned to this content. */
    public BoxRetentionPolicy.Info getRetentionPolicy() {
      return this.retentionPolicy;
    }

    /** @return the info about the user that created the retention policy assignment. */
    public BoxUser.Info getAssignedBy() {
      return this.assignedBy;
    }

    /** @return the time that the retention policy assignment was created. */
    public Date getAssignedAt() {
      return this.assignedAt;
    }

    /**
     * @return type of the content that is under retention. Can either be "enterprise" or "folder".
     */
    public String getAssignedToType() {
      return this.assignedToType;
    }

    /** @return id of the folder that is under retention. */
    public String getAssignedToID() {
      return this.assignedToID;
    }

    /** @return date the retention policy assignment begins */
    public String getStartDateField() {
      return this.startDateField;
    }

    /** @return the array of metadata field filters, if present */
    public List<MetadataFieldFilter> getFilterFields() {

      return this.filterFields;
    }

    /** {@inheritDoc} */
    @Override
    void parseJSONMember(JsonObject.Member member) {
      super.parseJSONMember(member);
      String memberName = member.getName();
      JsonValue value = member.getValue();
      try {
        if (memberName.equals("retention_policy")) {
          JsonObject policyJSON = value.asObject();
          if (this.retentionPolicy == null) {
            String policyID = policyJSON.get("id").asString();
            BoxRetentionPolicy policy = new BoxRetentionPolicy(getAPI(), policyID);
            this.retentionPolicy = policy.new Info(policyJSON);
          } else {
            this.retentionPolicy.update(policyJSON);
          }
        } else if (memberName.equals("assigned_to")) {
          JsonObject assignmentJSON = value.asObject();
          this.assignedToType = assignmentJSON.get("type").asString();
          if (this.assignedToType.equals(TYPE_ENTERPRISE)) {
            this.assignedToID = null;
          } else {
            this.assignedToID = assignmentJSON.get("id").asString();
          }
        } else if (memberName.equals("assigned_by")) {
          JsonObject userJSON = value.asObject();
          if (this.assignedBy == null) {
            String userID = userJSON.get("id").asString();
            BoxUser user = new BoxUser(getAPI(), userID);
            this.assignedBy = user.new Info(userJSON);
          } else {
            this.assignedBy.update(userJSON);
          }
        } else if (memberName.equals("assigned_at")) {
          this.assignedAt = BoxDateFormat.parse(value.asString());
        } else if (memberName.equals("start_date_field")) {
          this.startDateField = value.asString();
        } else if (memberName.equals("filter_fields")) {
          JsonArray jsonFilters = value.asArray();
          List<MetadataFieldFilter> filterFields = new ArrayList<>();
          for (int i = 0; i < jsonFilters.size(); i++) {
            filterFields.add(new MetadataFieldFilter(jsonFilters.get(i).asObject()));
          }
          this.filterFields = filterFields;
        }
      } catch (Exception e) {
        throw new BoxDeserializationException(memberName, value.toString(), e);
      }
    }
  }
}