{
  "$schema": "http://json-schema.org/draft-07/schema#",
  "definitions": {
    "gbtree": {
      "type": "object",
      "properties": {
        "name": {
          "const": "gbtree"
        },
        "model": {
          "type": "object",
          "properties": {
            "gbtree_model_param": {
              "$ref": "#/definitions/gbtree_model_param"
            },
            "trees": {
              "type": "array",
              "items": {
                "type": "object",
                "properties": {
                  "tree_param": {
                    "type": "object",
                    "properties": {
                      "num_nodes": {
                        "type": "string"
                      },
                      "size_leaf_vector": {
                        "type": "string"
                      },
                      "num_feature": {
                        "type": "string"
                      }
                    },
                    "required": [
                      "num_nodes",
                      "num_feature",
                      "size_leaf_vector"
                    ]
                  },
                  "id": {
                    "type": "integer"
                  },
                  "loss_changes": {
                    "type": "array",
                    "items": {
                      "type": "number"
                    }
                  },
                  "sum_hessian": {
                    "type": "array",
                    "items": {
                      "type": "number"
                    }
                  },
                  "base_weights": {
                    "type": "array",
                    "items": {
                      "type": "number"
                    }
                  },
                  "left_children": {
                    "type": "array",
                    "items": {
                      "type": "integer"
                    }
                  },
                  "right_children": {
                    "type": "array",
                    "items": {
                      "type": "integer"
                    }
                  },
                  "parents": {
                    "type": "array",
                    "items": {
                      "type": "integer"
                    }
                  },
                  "split_indices": {
                    "type": "array",
                    "items": {
                      "type": "integer"
                    }
                  },
                  "split_conditions": {
                    "type": "array",
                    "items": {
                      "type": "number"
                    }
                  },
                  "split_type": {
                    "type": "array",
                    "items": {
                      "type": "integer"
                    }
                  },
                  "default_left": {
                    "type": "array",
                    "items": {
                      "type": "boolean"
                    }
                  },
                  "categories": {
                    "type": "array",
                    "items": {
                      "type": "integer"
                    }
                  },
                  "categories_nodes": {
                    "type": "array",
                    "items": {
                      "type": "integer"
                    }
                  },
                  "categories_segments": {
                    "type": "array",
                    "items": {
                      "type": "integer"
                    }
                  },
                  "categorical_sizes": {
                    "type": "array",
                    "items": {
                      "type": "integer"
                    }
                  }
                },
                "required": [
                  "tree_param",
                  "loss_changes",
                  "sum_hessian",
                  "base_weights",
                  "left_children",
                  "right_children",
                  "parents",
                  "split_indices",
                  "split_conditions",
                  "default_left",
                  "categories",
                  "categories_nodes",
                  "categories_segments",
                  "categories_sizes"
                ]
              }
            },
            "tree_info": {
              "type": "array",
              "items": {
                "type": "integer"
              }
            }
          },
          "required": [
            "gbtree_model_param",
            "trees",
            "tree_info"
          ]
        }
      },
      "required": [
        "name",
        "model"
      ]
    },
    "gbtree_model_param": {
      "type": "object",
      "properties": {
        "num_trees": {
          "type": "string"
        },
        "size_leaf_vector": {
          "type": "string"
        }
      },
      "required": [
        "num_trees",
        "size_leaf_vector"
      ]
    },
    "tree_param": {
      "type": "object",
      "properties": {
        "num_nodes": {
          "type": "string"
        },
        "size_leaf_vector": {
          "type": "string"
        },
        "num_feature": {
          "type": "string"
        }
      },
      "required": [
        "num_nodes",
        "num_feature",
        "size_leaf_vector"
      ]
    },
    "reg_loss_param": {
      "type": "object",
      "properties": {
        "scale_pos_weight": {
          "type": "string"
        }
      }
    },
    "aft_loss_param": {
      "type": "object",
      "properties": {
        "aft_loss_distribution": {
          "type": "string"
        },
        "aft_loss_distribution_scale": {
          "type": "string"
        }
      }
    },
    "softmax_multiclass_param": {
      "type": "object",
      "properties": {
        "num_class": { "type": "string" }
      }
    },
    "lambda_rank_param": {
      "type": "object",
      "properties": {
        "num_pairsample": { "type": "string" },
        "fix_list_weight": { "type": "string" }
      }
    }
  },
  "type": "object",
  "properties": {
    "version": {
      "type": "array",
      "items": [
        {
          "type": "number",
          "const": 1
        },
        {
          "type": "number",
          "minimum": 0
        },
        {
          "type": "number",
          "minimum": 0
        }
      ],
      "minItems": 3,
      "maxItems": 3
    },
    "learner": {
      "type": "object",
      "properties": {
        "feature_names": {
          "type": "array",
          "items": {
              "type": "string"
          }
        },
        "feature_types": {
          "type": "array",
          "items": {
              "type": "string"
          }
        },
        "gradient_booster": {
          "oneOf": [
            {
              "$ref": "#/definitions/gbtree"
            },
            {
              "type": "object",
              "properties": {
                "name": { "const": "gblinear" },
                "model": {
                  "type": "object",
                  "properties": {
                    "weights": {
                      "type": "array",
                      "items": {
                        "type": "number"
                      }
                    }
                  }
                }
              }
            },
            {
              "type": "object",
              "properties": {
                "name": { "const": "dart" },
                "gbtree": {
                  "$ref": "#/definitions/gbtree"
                },
                "weight_drop": {
                  "type": "array",
                  "items": {
                    "type": "number"
                  }
                }
              },
              "required": [
                "name",
                "gbtree",
                "weight_drop"
              ]
            }
          ]
        },

        "objective": {
          "oneOf": [
            {
              "type": "object",
              "properties": {
                "name": { "const": "reg:squarederror" },
                "reg_loss_param": { "$ref": "#/definitions/reg_loss_param"}
              },
              "required": [
                "name",
                "reg_loss_param"
              ]
            },
            {
              "type": "object",
              "properties": {
                "name": { "const": "reg:pseudohubererror" },
                "reg_loss_param": { "$ref": "#/definitions/reg_loss_param"}
              },
              "required": [
                "name",
                "reg_loss_param"
              ]
            },
            {
              "type": "object",
              "properties": {
                "name": { "const": "reg:squaredlogerror" },
                "reg_loss_param": { "$ref": "#/definitions/reg_loss_param"}
              },
              "required": [
                "name",
                "reg_loss_param"
              ]
            },
            {
              "type": "object",
              "properties": {
                "name": { "const": "reg:linear" },
                "reg_loss_param": { "$ref": "#/definitions/reg_loss_param"}
              },
              "required": [
                "name",
                "reg_loss_param"
              ]
            },
            {
              "type": "object",
              "properties": {
                "name": { "const": "reg:logistic" },
                "reg_loss_param": { "$ref": "#/definitions/reg_loss_param"}
              },
              "required": [
                "name",
                "reg_loss_param"
              ]
            },
            {
              "type": "object",
              "properties": {
                "name": { "const": "binary:logistic" },
                "reg_loss_param": { "$ref": "#/definitions/reg_loss_param"}
              },
              "required": [
                "name",
                "reg_loss_param"
              ]
            },
            {
              "type": "object",
              "properties": {
                "name": { "const": "binary:logitraw" },
                "reg_loss_param": { "$ref": "#/definitions/reg_loss_param"}
              },
              "required": [
                "name",
                "reg_loss_param"
              ]
            },

            {
              "type": "object",
              "properties": {
                "name": { "const": "count:poisson" },
                "poisson_regression_param": {
                  "type": "object",
                  "properties": {
                    "max_delta_step": { "type": "string" }
                  }
                }
              },
              "required": [
                "name",
                "poisson_regression_param"
              ]
            },
            {
              "type": "object",
              "properties": {
                "name": { "const": "reg:tweedie" },
                "tweedie_regression_param": {
                  "type": "object",
                  "properties": {
                    "tweedie_variance_power": { "type": "string" }
                  }
                }
              },
              "required": [
                "name",
                "tweedie_regression_param"
              ]
            },
            {
              "type": "object",
              "properties": {
                "name": { "const": "survival:cox" }
              },
              "required": [ "name" ]
            },
            {
              "type": "object",
              "properties": {
                "name": { "const": "reg:gamma" }
              },
              "required": [ "name" ]
            },

            {
              "type": "object",
              "properties": {
                "name": { "const": "multi:softprob" },
                "softmax_multiclass_param": { "$ref": "#/definitions/softmax_multiclass_param"}
              },
              "required": [
                "name",
                "softmax_multiclass_param"
              ]
            },
            {
              "type": "object",
              "properties": {
                "name": { "const": "multi:softmax" },
                "softmax_multiclass_param": { "$ref": "#/definitions/softmax_multiclass_param"}
              },
              "required": [
                "name",
                "softmax_multiclass_param"
              ]
            },

            {
              "type": "object",
              "properties": {
                "name": { "const": "rank:pairwise" },
                "lambda_rank_param": { "$ref": "#/definitions/lambda_rank_param"}
              },
              "required": [
                "name",
                "lambda_rank_param"
              ]
            },
            {
              "type": "object",
              "properties": {
                "name": { "const": "rank:ndcg" },
                "lambda_rank_param": { "$ref": "#/definitions/lambda_rank_param"}
              },
              "required": [
                "name",
                "lambda_rank_param"
              ]
            },
            {
              "type": "object",
              "properties": {
                "name": { "const": "rank:map" },
                "lambda_rank_param": { "$ref": "#/definitions/lambda_rank_param"}
              },
              "required": [
                "name",
                "lambda_rank_param"
              ]
            },
            {
              "type": "object",
              "properties": {
                "name": {"const": "survival:aft"},
                "aft_loss_param": { "$ref": "#/definitions/aft_loss_param"}
              }
            },
            {
              "type": "object",
              "properties": {
                "name": {"const": "binary:hinge"}
              }
            }
          ]
        },

        "learner_model_param": {
          "type": "object",
          "properties": {
            "base_score": { "type": "string" },
            "num_class": { "type": "string" },
            "num_feature": { "type": "string" }
          }
        }
      },
      "required": [
        "gradient_booster",
        "objective"
      ]
    }
  },
  "required": [
    "version",
    "learner"
  ]
}
