require_relative 'internal/abstract_invocation_context'
require_relative 'internal/invocation_context_iterator'
require_relative '../core/interpreter/interpreter'
require_relative '../utils/exceptions/exception_thrower'

# InvocationContext is a class that represents a context for invoking commands.
# It implements several interfaces for different types of interactions.
# This class is used to construct chains of invocations, representing expressions of interaction that have not yet been executed.
# @see Refer to this {https://www.javonet.com/guides/v2/ruby/foundations/invocation-context article on Javonet Guides}
class InvocationContext < AbstractInvocationContext
  include Enumerable

  def initialize(runtime_name, connection_type, tcp_ip_address, command, is_executed = false)
    @is_executed = is_executed
    @runtime_name = runtime_name
    @connection_type = connection_type
    @tcp_ip_address = tcp_ip_address
    @current_command = command
    @response_command = nil
    @interpreter = Interpreter.new
    # generates error: ruby/lib/javonet.rb-ruby-sdk/sdk/internal/invocation_context.rb:17: warning: finalizer references object to be finalized
    # ObjectSpace.define_finalizer(self, self.finalize(@current_command, @is_executed, @interpreter, @connection_type, @tcp_ip_address))
  end

  def finalize(command, is_executed, interpreter, connection_type, tcp_ip_address)
    proc do
      if command.command_type == CommandType::REFERENCE && is_executed == true
        destruct_command = Command.new(@runtime_name, CommandType::DESTRUCT_REFERENCE, command.payload)
        interpreter.execute(destruct_command, connection_type, tcp_ip_address)
      end
    end
  end

  def iterator
    if not [CommandType::REFERENCE, CommandType::ARRAY_GET_ITEM, CommandType::ARRAY_SET_ITEM].include? @current_command.command_type
      raise "Object is not iterable"
    else
      InvocationContextIterator.new(self)
    end
  end

  def [](i)
    if not [CommandType::REFERENCE, CommandType::ARRAY_GET_ITEM].include? @current_command.command_type
      raise "Object is not iterable"
    else
      invocation_context_iterator = InvocationContextIterator.new(self)
      invocation_context_iterator[i]
    end
  end

  def []=(i, value)
    if not [CommandType::REFERENCE, CommandType::ARRAY_SET_ITEM, CommandType::ARRAY_GET_ITEM].include? @current_command.command_type
      raise "Object is not iterable"
    else
      invocation_context_iterator = InvocationContextIterator.new(self)
      invocation_context_iterator[i] = value
    end
  end

  # Executes the current command.
  # Because invocation context is building the intent of executing particular expression on target environment, we call the initial state of invocation context as non-materialized. 
  # The non-materialized context wraps either single command or chain of recursively nested commands.
  # Commands are becoming nested through each invocation of methods on Invocation Context.
  # Each invocation triggers the creation of new Invocation Context instance wrapping the current command with new parent command valid for invoked method.
  # Developer can decide on any moment of the materialization for the context taking full control of the chunks of the expression being transferred and processed on target runtime.
  # @return [InvocationContext] the InvocationContext after executing the command.
  # @see Refer to this {https://www.javonet.com/guides/v2/ruby/foundations/execute-method article on Javonet Guides}
  def execute
    @response_command = @interpreter.execute(@current_command, @connection_type, @tcp_ip_address)

    if @response_command.command_type == CommandType::EXCEPTION
      raise ExceptionThrower.throw_exception(@response_command)
    end

    if @response_command.command_type == CommandType::CREATE_CLASS_INSTANCE
      @current_command = @response_command
      @is_executed = true
      return self
    end

    InvocationContext.new(@runtime_name, @connection_type, @tcp_ip_address, @response_command, true)
  end

  # Invokes a static method on the target runtime.
  # @param method_name [String] The name of the static method to invoke.
  # @param args [Array] The arguments to pass to the static method.
  # @return [InvocationContext] A new InvocationContext instance that wraps the command to invoke the static method.
  # @see Refer to this {https://www.javonet.com/guides/v2/ruby/calling-methods/invoking-static-method article on Javonet Guides}
  def invoke_static_method(method_name, *args)
    local_command = Command.new(@runtime_name, CommandType::INVOKE_STATIC_METHOD, [method_name, *args])
    InvocationContext.new(@runtime_name, @connection_type, @tcp_ip_address, build_command(local_command))
  end

  # Invokes an instance method on the target runtime.
  # @param method_name [String] The name of the instance method to invoke.
  # @param args [Array] The arguments to pass to the instance method.
  # @return [InvocationContext] A new InvocationContext instance that wraps the command to invoke the instance method.
  # @see Refer to this {https://www.javonet.com/guides/v2/ruby/calling-methods/creating-instance-and-calling-instance-methods article on Javonet Guides}

  def invoke_instance_method(method_name, *args)
    local_command = Command.new(@runtime_name, CommandType::INVOKE_INSTANCE_METHOD, [method_name, *args])
    InvocationContext.new(@runtime_name, @connection_type, @tcp_ip_address, build_command(local_command))
  end

  # Creates a new instance of a class in the target runtime.
  # @param args [Array] The arguments to class constructor
  # @return [InvocationContext] A new InvocationContext instance that wraps the command to create the instance.
  # @see https://www.javonet.com/guides/v2/ruby/calling-methods/creating-instance-and-calling-instance-methods
  def create_instance(*args)
    local_command = Command.new(@runtime_name, CommandType::CREATE_CLASS_INSTANCE, [*args])
    InvocationContext.new(@runtime_name, @connection_type, @tcp_ip_address, build_command(local_command))
  end

  # Retrieves the value of a static field from the target runtime.
  # @param field_name [String] The name of the static field to get.
  # @return [InvocationContext] A new InvocationContext instance that wraps the command to get the static field.
  # @see Refer to this {https://www.javonet.com/guides/v2/ruby/fields-and-properties/getting-and-setting-values-for-static-fields-and-properties article on Javonet Guides}
  def get_static_field(field_name)
    local_command = Command.new(@runtime_name, CommandType::GET_STATIC_FIELD, [field_name])
    InvocationContext.new(@runtime_name, @connection_type, @tcp_ip_address, build_command(local_command))
  end

  # Sets the value of a static field in the target runtime.
  # @param field_name [String] The name of the static field to set.
  # @param value [Object] The new value of the static field.
  # @return [InvocationContext] A new InvocationContext instance that wraps the command to set the static field.
  # @see Refer to this {https://www.javonet.com/guides/v2/ruby/fields-and-properties/getting-and-setting-values-for-static-fields-and-properties article on Javonet Guides}
  def set_static_field(field_name, value)
    local_command = Command.new(@runtime_name, CommandType::SET_STATIC_FIELD, [field_name, value])
    InvocationContext.new(@runtime_name, @connection_type, @tcp_ip_address, build_command(local_command))
  end

  # Retrieves the value of an instance field from the target runtime.
  # @param field_name [String] The name of the instance field to get.
  # @return [InvocationContext] A new InvocationContext instance that wraps the command to get the instance field.
  # @see Refer to this {https://www.javonet.com/guides/v2/ruby/fields-and-properties/getting-and-setting-values-for-instance-fields-and-properties article on Javonet Guides}
  def get_instance_field(field_name)
    local_command = Command.new(@runtime_name, CommandType::GET_INSTANCE_FIELD, [field_name])
    InvocationContext.new(@runtime_name, @connection_type, @tcp_ip_address, build_command(local_command))
  end

  # Sets the value of an instance field in the target runtime.
  # @param field_name [String] The name of the instance field to set.
  # @param value [Object] The new value of the instance field.
  # @return [InvocationContext] A new InvocationContext instance that wraps the command to set the instance field.
  # @see Refer to this {https://www.javonet.com/guides/v2/ruby/fields-and-properties/getting-and-setting-values-for-instance-fields-and-properties article on Javonet Guides}
  def set_instance_field(field_name, value)
    local_command = Command.new(@runtime_name, CommandType::SET_INSTANCE_FIELD, [field_name, value])
    InvocationContext.new(@runtime_name, @connection_type, @tcp_ip_address, build_command(local_command))
  end

  # Retrieves the value at a specific indexes in an array from the target runtime.
  # @param indexes [Array] The indexes to pass to the get index command.
  # @return [InvocationContext] A new InvocationContext instance that wraps the command to get the index.
  # @see Refer to this {https://www.javonet.com/guides/v2/ruby/arrays-and-collections/one-dimensional-arrays article on Javonet Guides}
  def get_index(*indexes)
    local_command = Command.new(@runtime_name, CommandType::ARRAY_GET_ITEM, [*indexes])
    InvocationContext.new(@runtime_name, @connection_type, @tcp_ip_address, build_command(local_command))
  end

  # Sets the value at a specific index in an array in the target runtime.
  # @param indexes [Array] The indexes where new value should be set
  # @param value [Object] The new value to set at the indexes.
  # @return [InvocationContext] A new InvocationContext instance that wraps the command to set the index.
  # @see https://www.javonet.com/guides/v2/ruby/arrays-and-collections/one-dimensional-arrays Setting Array Element Guide
  def set_index(indexes, value)
    local_command = Command.new(@runtime_name, CommandType::ARRAY_SET_ITEM, [indexes, value])
    InvocationContext.new(@runtime_name, @connection_type, @tcp_ip_address, build_command(local_command))
  end

  # Retrieves the number of elements from the target runtime.
  # @return [InvocationContext] A new InvocationContext instance that wraps the command to get the size.
  # @see Refer to this {https://www.javonet.com/guides/v2/ruby/arrays-and-collections/one-dimensional-arrays article on Javonet Guides}
  def get_size
    local_command = Command.new(@runtime_name, CommandType::ARRAY_GET_SIZE, [])
    InvocationContext.new(@runtime_name, @connection_type, @tcp_ip_address, build_command(local_command))
  end

  # Retrieves the rank of an array from the target runtime.
  # @return [InvocationContext] A new InvocationContext instance that wraps the command to get the rank.
  # @see Refer to this {https://www.javonet.com/guides/v2/ruby/arrays-and-collections/multidimensional-arrays article on Javonet Guides}
  def get_rank
    local_command = Command.new(@runtime_name, CommandType::ARRAY_GET_RANK, [])
    InvocationContext.new(@runtime_name, @connection_type, @tcp_ip_address, build_command(local_command))
  end

  # Invokes a generic static method on the target runtime.
  # @param method_name [String] The name of the generic static method to invoke.
  # @param args [Array] The arguments to pass to the generic static method.
  # @return [InvocationContext] A new InvocationContext instance that wraps the command to invoke the generic static method.
  # @see Refer to this {https://www.javonet.com/guides/v2/ruby/generics/calling-generic-static-method article on Javonet Guides}
  def invoke_generic_static_method(method_name, *args)
    local_command = Command.new(@runtime_name, CommandType::INVOKE_GENERIC_STATIC_METHOD, [method_name, *args])
    InvocationContext.new(@runtime_name, @connection_type, @tcp_ip_address, build_command(local_command))
  end

  # Invokes a generic method on the target runtime.
  # @param method_name [String] The name of the generic method to invoke.
  # @param args [Array] The arguments to pass to the generic method.
  # @return [InvocationContext] A new InvocationContext instance that wraps the command to invoke the generic method.
  # @see Refer to this {https://www.javonet.com/guides/v2/ruby/generics/calling-generic-instance-method article on Javonet Guides}
  def invoke_generic_method(method_name, *args)
    local_command = Command.new(@runtime_name, CommandType::INVOKE_GENERIC_METHOD, [method_name, *args])
    InvocationContext.new(@runtime_name, @connection_type, @tcp_ip_address, build_command(local_command))
  end

  # Retrieves the name of an enum from the target runtime.
  # @return [InvocationContext] A new InvocationContext instance that wraps the command to get the enum name.
  # @see Refer to this {https://www.javonet.com/guides/v2/ruby/enums/using-enum-type article on Javonet Guides}
  def get_enum_name
    local_command = Command.new(@runtime_name, CommandType::GET_ENUM_NAME, [])
    InvocationContext.new(@runtime_name, @connection_type, @tcp_ip_address, build_command(local_command))
  end

  # Retrieves the value of an enum from the target runtime.
  # @return [InvocationContext] A new InvocationContext instance that wraps the command to get the enum value.
  # @see Refer to this {https://www.javonet.com/guides/v2/ruby/enums/using-enum-type article on Javonet Guides}
  def get_enum_value
    local_command = Command.new(@runtime_name, CommandType::GET_ENUM_VALUE, [])
    InvocationContext.new(@runtime_name, @connection_type, @tcp_ip_address, build_command(local_command))
  end

  # Creates a null object of a specific type in the target runtime.
  # @return [InvocationContext] An InvocationContext instance with the command to create a null object.
  # @see Refer to this {https://www.javonet.com/guides/v2/ruby/null-handling/create-null-object article on Javonet Guides}
  def create_null
    local_command = Command.new(@runtime_name, CommandType::CREATE_NULL, [])
    InvocationContext.new(@runtime_name, @connection_type, @tcp_ip_address, build_command(local_command))
  end

  # Retrieves the value of a reference from the target runtime.
  # @return [InvocationContext] A new InvocationContext instance that wraps the command to get the ref value.
  # @see Refer to this {https://www.javonet.com/guides/v2/ruby/methods-arguments/passing-arguments-by-reference-with-ref-keyword article on Javonet Guides}
  def get_ref_value
    local_command = Command.new(@runtime_name, CommandType::GET_REF_VALUE, [])
    InvocationContext.new(@runtime_name, @connection_type, @tcp_ip_address, build_command(local_command))
  end

  # Retrieves an array from the target runtime.
  # @return [Object] A new InvocationContext instance that wraps the command to retrieve the array.
  # @see Refer to this {https://www.javonet.com/guides/v2/ruby/arrays-and-collections/one-dimensional-arrays article on Javonet Guides}
  def retrieve_array
    local_command = Command.new(@runtime_name, CommandType::RETRIEVE_ARRAY, [])
    local_inv_ctx = InvocationContext.new(@runtime_name, @connection_type, @tcp_ip_address, build_command(local_command))
    local_inv_ctx.execute
    local_inv_ctx.response_command.payload
  end

  # Retrieves the value of the current command from the target runtime.
  # @return [Object] The value of the current command.
  # @see https://www.javonet.com/guides/v2/ruby/foundations/execute-method Getting Command Value Guide
  def get_value
    @current_command.payload[0]
  end

  def build_command(command)
    command.payload.each_index { |i|
      command.payload[i] = encapsulate_payload_item(command.payload[i])
    }
    command.prepend_arg_to_payload(@current_command)
  end

  def encapsulate_payload_item(payload_item)
    if payload_item.is_a? Command
      payload_item.payload.each_index { |i|
        payload_item.payload[i] = encapsulate_payload_item(payload_item.payload[i])
      }
      return payload_item

    elsif payload_item.is_a? InvocationContext
      return payload_item.current_command

    elsif payload_item.is_a? Array
      payload_item.each_index { |i|
        payload_item[i] = encapsulate_payload_item(payload_item[i])
      }
      return Command.new(@runtime_name, CommandType::ARRAY, [*payload_item])

    else
      return Command.new(@runtime_name, CommandType::VALUE, [*payload_item])

    end
  end

  def current_command
    @current_command
  end

  def response_command
    @response_command
  end

end