#pragma once

#include <string>

#include "utils.hpp"

#include "tree_sitter/api.h"

extern "C" const TSLanguage *tree_sitter_lang();

namespace parser {

class ParseTree {
public:
  class Node {
  public:
    Node(const TSNode &node, const std::string *source)
        : node_(node), source_(source) {}

    std::string get_type() const {
      if (is_null()) {
        error_handling::handle_general_error(
            "Null parsing node method called (get_type)");
      }
      return ts_node_type(node_);
    }

    std::pair<size_t, size_t> get_start_point() const {
      if (is_null()) {
        error_handling::handle_general_error(
            "Null parsing node method called (get_start_point)");
      }

      TSPoint point = ts_node_start_point(node_);
      return {point.row, point.column};
    }

    std::pair<size_t, size_t> get_end_point() const {
      if (is_null()) {
        error_handling::handle_general_error(
            "Null parsing node method called (get_end_point)");
      }

      TSPoint point = ts_node_end_point(node_);
      return {point.row, point.column};
    }

    std::string get_as_sexpression() const {
      if (is_null()) {
        error_handling::handle_general_error(
            "Null parsing node method called (get_as_sexpression)");
      }
      return ts_node_string(node_);
    }

    std::string get_value() const { // from source
      if (is_null()) {
        error_handling::handle_general_error(
            "Null parsing node method called (get_value)");
      }
      size_t start = ts_node_start_byte(node_);
      size_t end = ts_node_end_byte(node_);
      return source_->substr(start, end - start);
    }

    size_t get_value_length() const { // from source
      if (is_null()) {
        error_handling::handle_general_error(
            "Null parsing node method called (get_value_length)");
      }
      size_t start = ts_node_start_byte(node_);
      size_t end = ts_node_end_byte(node_);
      return end - start;
    }

    bool is_null() const { return ts_node_is_null(node_); }

    bool is_named() const {
      if (is_null()) {
        error_handling::handle_general_error(
            "Null parsing node method called (is_named)");
      }
      return ts_node_is_named(node_);
    }

    bool is_missing() const {
      if (is_null()) {
        error_handling::handle_general_error(
            "Null parsing node method called (is_missing)");
      }
      return ts_node_is_missing(node_);
    }

    bool is_extra() const { // comments, etc.
      if (is_null()) {
        error_handling::handle_general_error(
            "Null parsing node method called (is_extra)");
      }
      return ts_node_is_extra(node_);
    }

    bool has_error() const {
      if (is_null()) {
        error_handling::handle_general_error(
            "Null parsing node method called (has_error)");
      }
      return ts_node_has_error(node_);
    }

    Node nth_child(size_t n) const {
      if (is_null()) {
        error_handling::handle_general_error(
            "Null parsing node method called (nth_child)");
      }
      return Node(ts_node_child(node_, n), source_);
    }

    size_t child_count() const {
      if (is_null()) {
        error_handling::handle_general_error(
            "Null parsing node method called (child_count)");
      }
      return ts_node_child_count(node_);
    }

    Node nth_named_child(size_t n) const {
      if (is_null()) {
        error_handling::handle_general_error(
            "Null parsing node method called (nth_named_child)");
      }
      return Node(ts_node_named_child(node_, n), source_);
    }
    size_t named_child_count() const {
      if (is_null()) {
        error_handling::handle_general_error(
            "Null parsing node method called (named_child_count)");
      }
      return ts_node_named_child_count(node_);
    }

    Node child_by_field_name(const std::string &name) const {
      if (is_null()) {
        error_handling::handle_general_error(
            "Null parsing node method called (child_by_field_name)");
      }
      return Node(ts_node_child_by_field_name(node_, name.c_str(), name.size()),
                  source_);
    }

    Node previous_sibling() const {
      if (is_null()) {
        error_handling::handle_general_error(
            "Null parsing node method called (previous_sibling)");
      }
      return Node(ts_node_prev_sibling(node_), source_);
    }

    Node previous_named_sibling() const {
      if (is_null()) {
        error_handling::handle_general_error(
            "Null parsing node method called (previous_named_sibling)");
      }
      return Node(ts_node_prev_named_sibling(node_), source_);
    }

    Node next_sibling() const {
      if (is_null()) {
        error_handling::handle_general_error(
            "Null parsing node method called (next_sibling)");
      }
      return Node(ts_node_next_sibling(node_), source_);
    }

    Node next_named_sibling() const {
      if (is_null()) {
        error_handling::handle_general_error(
            "Null parsing node method called (next_named_sibling)");
      }
      return Node(ts_node_next_named_sibling(node_), source_);
    }

  private:
    TSNode node_;
    const std::string *source_;
  };

  ParseTree(const std::string &source) : source_(source) {
    TSParser *parser = ts_parser_new();
    ts_parser_set_language(parser, tree_sitter_lang());

    tree_ = ts_parser_parse_string(parser, nullptr, source_.c_str(),
                                   source_.size());

    ts_parser_delete(parser);
  }

  ParseTree(const ParseTree &parse_tree)
      : tree_(ts_tree_copy(parse_tree.tree_)), source_(parse_tree.source_) {}

  Node get_root() const { return Node(ts_tree_root_node(tree_), &source_); }

  ~ParseTree() { ts_tree_delete(tree_); }

  bool is_properly_parsed() { // TODO: find place
    return !get_root().has_error();
  }

private:
  TSTree *tree_;
  std::string source_; // for token value extraction
};

} // namespace parser