#include "../include/basic_builders.hpp"

#include "basic_nodes.hpp"

namespace builders {

namespace utils {
std::optional<char> to_escape_symbol(char symbol) {
  switch (symbol) {
  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 's':
    return ' ';
  default:
    return std::nullopt;
  }
}

} // namespace utils

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

// --- literals

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

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

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

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

  // 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(buildNode(parser_node), literal);
}

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

  // remove '' from both sides (''x'')
  literal.pop_back();
  literal.pop_back();
  literal = literal.substr(1, literal.size() - 2);

  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(buildNode(parser_node), ch);
}

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

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

nodes::Literal buildUnitLiteral(parser::ParseTree::Node parser_node) {
  return nodes::Literal(buildNode(parser_node), nodes::unit{});
}

nodes::Literal buildNullLiteral(parser::ParseTree::Node parser_node) {
  return nodes::Literal(buildNode(parser_node), nodes::null{});
}

// --- identifiers

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

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

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

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

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

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

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

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

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

} // namespace builders