# typed: strict
# frozen_string_literal: true

module RubyLsp
  module Requests
    # :nodoc:
    class BaseRequest < SyntaxTree::Visitor
      extend T::Sig
      extend T::Helpers

      abstract!

      # We must accept rest keyword arguments here, so that the argument count matches when
      # SyntaxTree::WithScope#initialize invokes `super` for Sorbet. We don't actually use these parameters for
      # anything. We can remove these arguments once we drop support for Ruby 2.7
      # https://github.com/ruby-syntax-tree/syntax_tree/blob/4dac90b53df388f726dce50ce638a1ba71cc59f8/lib/syntax_tree/with_scope.rb#L122
      sig { params(document: Document, _kwargs: T.untyped).void }
      def initialize(document, **_kwargs)
        @document = document

        # Parsing the document here means we're taking a lazy approach by only doing it when the first feature request
        # is received by the server. This happens because {Document#parse} remembers if there are new edits to be parsed
        @document.parse

        super()
      end

      sig { abstract.returns(Object) }
      def run; end

      # Syntax Tree implements `visit_all` using `map` instead of `each` for users who want to use the pattern
      # `result = visitor.visit(tree)`. However, we don't use that pattern and should avoid producing a new array for
      # every single node visited
      sig { params(nodes: T::Array[SyntaxTree::Node]).void }
      def visit_all(nodes)
        nodes.each { |node| visit(node) }
      end

      sig { params(node: SyntaxTree::Node).returns(Interface::Range) }
      def range_from_syntax_tree_node(node)
        loc = node.location

        Interface::Range.new(
          start: Interface::Position.new(
            line: loc.start_line - 1,
            character: loc.start_column,
          ),
          end: Interface::Position.new(line: loc.end_line - 1, character: loc.end_column),
        )
      end

      sig do
        params(node: T.any(SyntaxTree::ConstPathRef, SyntaxTree::ConstRef, SyntaxTree::TopConstRef)).returns(String)
      end
      def full_constant_name(node)
        name = +node.constant.value
        constant = T.let(node, SyntaxTree::Node)

        while constant.is_a?(SyntaxTree::ConstPathRef)
          constant = constant.parent

          case constant
          when SyntaxTree::ConstPathRef
            name.prepend("#{constant.constant.value}::")
          when SyntaxTree::VarRef
            name.prepend("#{constant.value.value}::")
          end
        end

        name
      end

      sig do
        params(
          node: SyntaxTree::Node,
          position: Integer,
          node_types: T::Array[T.class_of(SyntaxTree::Node)],
        ).returns([T.nilable(SyntaxTree::Node), T.nilable(SyntaxTree::Node)])
      end
      def locate(node, position, node_types: [])
        queue = T.let(node.child_nodes.compact, T::Array[T.nilable(SyntaxTree::Node)])
        closest = node

        until queue.empty?
          candidate = queue.shift

          # Skip nil child nodes
          next if candidate.nil?

          # Add the next child_nodes to the queue to be processed
          queue.concat(candidate.child_nodes)

          # Skip if the current node doesn't cover the desired position
          loc = candidate.location
          next unless (loc.start_char...loc.end_char).cover?(position)

          # If the node's start character is already past the position, then we should've found the closest node already
          break if position < loc.start_char

          # If there are node types to filter by, and the current node is not one of those types, then skip it
          next if node_types.any? && node_types.none? { |type| candidate.is_a?(type) }

          # If the current node is narrower than or equal to the previous closest node, then it is more precise
          closest_loc = closest.location
          if loc.end_char - loc.start_char <= closest_loc.end_char - closest_loc.start_char
            parent = T.let(closest, SyntaxTree::Node)
            closest = candidate
          end
        end

        [closest, parent]
      end

      sig { params(node: T.nilable(SyntaxTree::Node), range: T.nilable(T::Range[Integer])).returns(T::Boolean) }
      def visible?(node, range)
        return true if range.nil?
        return false if node.nil?

        loc = node.location
        range.cover?(loc.start_line - 1) && range.cover?(loc.end_line - 1)
      end
    end
  end
end