// SPDX-License-Identifier: Apache-2.0
syntax = "proto3";

package substrait;

import "substrait/parameterized_types.proto";
import "substrait/type.proto";
import "substrait/type_expressions.proto";

option csharp_namespace = "Substrait.Protobuf";
option go_package = "github.com/substrait-io/substrait-go/proto";
option java_multiple_files = true;
option java_package = "io.substrait.proto";

// List of function signatures available.
message FunctionSignature {
  message FinalArgVariadic {
    // the minimum number of arguments allowed for the list of final arguments
    // (inclusive).
    int64 min_args = 1;

    // the maximum number of arguments allowed for the list of final arguments
    // (exclusive)
    int64 max_args = 2;

    // the type of parameterized type consistency
    ParameterConsistency consistency = 3;

    enum ParameterConsistency {
      PARAMETER_CONSISTENCY_UNSPECIFIED = 0;

      // All argument must be the same concrete type.
      PARAMETER_CONSISTENCY_CONSISTENT = 1;

      // Each argument can be any possible concrete type afforded by the bounds
      // of any parameter defined in the arguments specification.
      PARAMETER_CONSISTENCY_INCONSISTENT = 2;
    }
  }

  message FinalArgNormal {}

  message Scalar {
    repeated Argument arguments = 2;
    repeated string name = 3;
    Description description = 4;

    bool deterministic = 7;
    bool session_dependent = 8;

    DerivationExpression output_type = 9;

    oneof final_variable_behavior {
      FinalArgVariadic variadic = 10;
      FinalArgNormal normal = 11;
    }

    repeated Implementation implementations = 12;
  }

  message Aggregate {
    repeated Argument arguments = 2;
    string name = 3;
    Description description = 4;

    bool deterministic = 7;
    bool session_dependent = 8;

    DerivationExpression output_type = 9;

    oneof final_variable_behavior {
      FinalArgVariadic variadic = 10;
      FinalArgNormal normal = 11;
    }

    bool ordered = 14;
    uint64 max_set = 12;
    Type intermediate_type = 13;

    repeated Implementation implementations = 15;
  }

  message Window {
    repeated Argument arguments = 2;
    repeated string name = 3;
    Description description = 4;

    bool deterministic = 7;
    bool session_dependent = 8;

    DerivationExpression intermediate_type = 9;
    DerivationExpression output_type = 10;
    oneof final_variable_behavior {
      FinalArgVariadic variadic = 16;
      FinalArgNormal normal = 17;
    }
    bool ordered = 11;
    uint64 max_set = 12;
    WindowType window_type = 14;
    repeated Implementation implementations = 15;

    enum WindowType {
      WINDOW_TYPE_UNSPECIFIED = 0;
      WINDOW_TYPE_STREAMING = 1;
      WINDOW_TYPE_PARTITION = 2;
    }
  }

  message Description {
    string language = 1;
    string body = 2;
  }

  message Implementation {
    Type type = 1;
    string uri = 2;

    enum Type {
      TYPE_UNSPECIFIED = 0;
      TYPE_WEB_ASSEMBLY = 1;
      TYPE_TRINO_JAR = 2;
    }
  }

  message Argument {
    string name = 1;

    oneof argument_kind {
      ValueArgument value = 2;
      TypeArgument type = 3;
      EnumArgument enum = 4;
    }

    message ValueArgument {
      ParameterizedType type = 1;
      bool constant = 2;
    }

    message TypeArgument {
      ParameterizedType type = 1;
    }

    message EnumArgument {
      repeated string options = 1;
      bool optional = 2;
    }
  }
}
