#include "basic_builders.hpp"

#include "basic_nodes.hpp"
#include "error_handling.hpp"
#include "tokens.hpp"
#include "tree_sitter_wrapper.hpp"

namespace builders {

namespace utils {
std::optional<char> to_escape_symbol(char ch) {
  switch (ch) {
  case 'a':
    return '\a';
  case 'b':
    return '\b';
  case 'e':
    return '\e';
  case 'f':
    return '\f';
  case 'n':
    return '\n';
  case 'r':
    return '\r';
  case 't':
    return '\t';
  case 'v':
    return '\v';
  case '\'':
    return '\'';
  case '\"':
    return '\"';
  case 's':
    return ' ';
  default:
    return std::nullopt;
  }
}

} // namespace utils

nodes::Modifier build_modifier(parser::ParseTree::Node parser_node) {
  std::string modifier = parser_node.get_value();

  if (modifier == "?") {
    return nodes::Modifier::OR_FALSE;
  } else if (modifier == "!") {
    return nodes::Modifier::OR_RETURN;
  } else if (modifier == "->" || modifier == "out") {
    return nodes::Modifier::OUT;
  } else if (modifier == "<-" || modifier == "in") {
    return nodes::Modifier::IN;
  } else if (modifier == "<>" || modifier == "ref") {
    return nodes::Modifier::REF;
  }
  return nodes::Modifier::NONE;
}

nodes::Node build_node(parser::ParseTree::Node parser_node) {
  return nodes::Node(parser_node.get_start_point(),
                     parser_node.get_end_point());
}

// --- literals

nodes::Literal build_float_number_literal(parser::ParseTree::Node parser_node) {
  return nodes::Literal(build_node(parser_node),
                        std::stod(parser_node.get_value()));
}

nodes::Literal build_number_literal(parser::ParseTree::Node parser_node) {
  return nodes::Literal(build_node(parser_node),
                        std::stoll(parser_node.get_value()));
}

nodes::Literal build_string_literal(parser::ParseTree::Node parser_node) {
  std::string literal = parser_node.get_value();

  // remove " from both sides ("string")
  literal = literal.substr(1, literal.size() - 2);

  // replace escape sequences with escape characters
  bool is_escape_symbol = false;
  size_t j = 0;
  for (size_t i = 0; i < literal.size(); ++i, ++j) {
    if (literal[i] == '\\' && !is_escape_symbol) {
      is_escape_symbol = true;
    } else {
      if (is_escape_symbol) {
        --j;
        auto maybe_escape_symbol = utils::to_escape_symbol(literal[i]);
        if (maybe_escape_symbol.has_value()) {
          literal[j] = maybe_escape_symbol.value();
        } else {
          literal[j] = literal[i];
        }
      } else {
        if (j != i) {
          literal[j] = literal[i];
        }
      }
    }
  }
  literal.resize(j);

  return nodes::Literal(build_node(parser_node), literal);
}

nodes::Literal build_char_literal(parser::ParseTree::Node parser_node) {
  std::string literal = parser_node.get_value();

  // remove '' from both sides (''x'')
  literal = literal.substr(2, literal.size() - 4);

  char ch = '\0';

  // replace escape sequence with escape character
  if (literal[0] == '\\') {
    auto maybe_escape_symbol = utils::to_escape_symbol(literal.back());
    if (maybe_escape_symbol.has_value()) {
      ch = maybe_escape_symbol.value();
    } else {
      ch = literal.back();
    }
  } else {
    ch = literal.back();
  }

  return nodes::Literal(build_node(parser_node), ch);
}

nodes::Literal build_bool_literal(parser::ParseTree::Node parser_node) {
  std::string literal = parser_node.get_value();

  return nodes::Literal(build_node(parser_node),
                        literal == "true" ? true : false);
}

nodes::Literal build_unit_literal(parser::ParseTree::Node parser_node) {
  return nodes::Literal(build_node(parser_node), nodes::unit{});
}

nodes::Literal build_null_literal(parser::ParseTree::Node parser_node) {
  return nodes::Literal(build_node(parser_node), nodes::null{});
}

// --- identifiers

nodes::Identifier build_identifier(parser::ParseTree::Node parser_node) {
  tokens::Type type = tokens::string_to_type(parser_node.get_type());

  switch (type) {
  case tokens::Type::PLACEHOLDER:
    return build_placeholder(parser_node);
  case tokens::Type::SIMPLE_NAME_IDENTIFIER:
    return build_simple_name(parser_node);
  case tokens::Type::SIMPLE_TYPE_IDENTIFIER:
    return build_simple_type(parser_node);
  case tokens::Type::TYPECLASS_IDENTIFIER:
    return build_typeclass(parser_node);
  case tokens::Type::ARGUMENT_NAME_IDENTIFIER:
    return build_argument_name(parser_node);
  case tokens::Type::ARGUMENT_TYPE_IDENTIFIER:
    return build_argument_type(parser_node);
  case tokens::Type::OPERATOR:
  case tokens::Type::OPERATOR_TAIL1:
  case tokens::Type::OPERATOR_TAIL2:
  case tokens::Type::OPERATOR_TAIL3:
    return build_operator(parser_node);
  // [used as string]
  // case tokens::Type::ANNOTATION_IDENTIFIER:
  //   return build_annotation(parser_node);
  default:
    error_handling::handle_parsing_error("Unexprected identifier node type",
                                         parser_node);
  }
  error_handling::handle_general_error("Unreachable");
  exit(1); // unreachable
}

nodes::Identifier build_simple_name(parser::ParseTree::Node parser_node) {
  return nodes::Identifier(build_node(parser_node),
                           nodes::Identifier::SIMPLE_NAME,
                           parser_node.get_value());
}

nodes::Identifier build_simple_type(parser::ParseTree::Node parser_node) {
  return nodes::Identifier(build_node(parser_node),
                           nodes::Identifier::SIMPLE_TYPE,
                           parser_node.get_value());
}

nodes::Identifier build_typeclass(parser::ParseTree::Node parser_node) {
  return nodes::Identifier(build_node(parser_node),
                           nodes::Identifier::TYPECLASS,
                           parser_node.get_value());
}

nodes::Identifier build_argument_name(parser::ParseTree::Node parser_node) {
  return nodes::Identifier(build_node(parser_node),
                           nodes::Identifier::ARGUMENT_NAME,
                           parser_node.get_value());
}

nodes::Identifier build_argument_type(parser::ParseTree::Node parser_node) {
  return nodes::Identifier(build_node(parser_node),
                           nodes::Identifier::ARGUMENT_TYPE,
                           parser_node.get_value());
}

// Annotations are used as strings
std::string build_annotation(parser::ParseTree::Node parser_node) {
  std::string identifier = parser_node.get_value();

  // identifier.size() > 0 by parsing convention
  identifier = identifier.substr(1, identifier.size() - 1);

  return identifier;
}

nodes::Identifier build_operator(parser::ParseTree::Node parser_node) {
  std::string identifier = parser_node.get_value();

  // --- points needed for proper printing
  // if (identifier.size() > 0 && identifier.front() != '.') {
  //   // for not point only identifiers
  //   while (identifier.size() > 0 && identifier.back() == '.') {
  //     identifier.pop_back();
  //   }
  // }
  // ---

  return nodes::Identifier(build_node(parser_node), nodes::Identifier::OPERATOR,
                           identifier);
}

nodes::Identifier build_placeholder(parser::ParseTree::Node parser_node) {
  return nodes::Identifier(build_node(parser_node),
                           nodes::Identifier::PLACEHOLDER, "_");
}

// --- empty lines

nodes::EmptyLines build_empty_lines(parser::ParseTree::Node parser_node) {
  return nodes::EmptyLines(build_node(parser_node),
                           parser_node.get_value_length() - 1);
}

} // namespace builders