#pragma once
#include <ncurses.h>
#include <vector>
#include <stack>
#include <fstream>
#include <iostream>

#define TAB_SIZE 8
constexpr int RANDOM_SEED = 666;

using std::string;
using std::vector;
using std::stack;
typedef unsigned long long count_type;

// Position
struct position {
	count_type r, c;
	position operator+(count_type offset) { return {r + offset, c}; }
};

// String utilities
count_type get_tab_length(count_type c);
string substitute_tabs(string s);
count_type get_tab_offset(count_type c, string text);

//// Treap

// Treap node representation of a line
struct line {
	count_type priority, size; // Treap innards
	string text; // Content
	line *left, *right; // Sons
	line *next_in_version;

	void set_left(line *_left) {
		left = _left;
		update_size();
	}
	void set_right(line *_right) {
		right = _right;
		update_size();
	}

	void update_size() { size = 1 + (left == nullptr ? 0 : left->size) + (right == nullptr ? 0 : right->size); }

	line(count_type _p, string _t) :
		priority(_p), text(_t), size(1), left(nullptr), right(nullptr), next_in_version(nullptr) {}

	line(count_type _p, string _t, line *_left, line *_right, line *_next) :
		priority(_p), text(_t), left(_left), right(_right), next_in_version(_next) {
		update_size();
	}

	line(line *l) :
		priority(l->priority), text(l->text), left(l->left), right(l->right), next_in_version(nullptr) {
		update_size();
	}
};
struct change { count_type row, count; };

// Treap data structure
class Treap {
	stack<change> changes;
	stack<line*> root;
	line* get_root() { return root.top(); };

	line* insert(line *l, count_type k, string s, bool new_version);
	line* remove(line *l, count_type k);
	line* update(line *l, count_type k, string s, bool new_version);

	line* pick_higher(line *l);
	void delete_version(line *l);
	count_type get_size(line *l);
	count_type get_priority(line *l);
	line* find(line *l, count_type k);
	count_type bulk_find(vector<string> *vec, line *l, count_type k, count_type count);

public:
	// General operations
	Treap() { srand(RANDOM_SEED); root.push(nullptr); }
	count_type size() { return get_size(get_root()); }
	void clear();

	// Versioning
	count_type undo();
	count_type version() { return root.size()-1; }
	void compress_versions(count_type count);

	// Line getters
	string get_line(count_type r, bool substitute_tab = true);
	vector<string> bulk_get_line(count_type r, count_type count);
	count_type get_tab_offset(position p) { return ::get_tab_offset(p.c, get_line(p.r, 0)); }

	// Line meta-operations
	void insert(count_type k, string s, bool new_version = true);
	void remove(count_type k);
	void update(count_type k, string s, bool new_version = true);

	// Other line operations
	void split_line(position p, bool should_compress = true);
	void merge_line(count_type k, bool should_compress = true);
	void insert(position p, string t);
	void remove(position p, count_type len = 1);
};

//// Selection
class Selection {
	Treap *file;
	Treap content;

	template <typename F, typename G>
	void apply_on_selection(position p, F func, G func2);
public:
	Selection() {}
	Selection(Treap *_file) { file = _file; }
	position pos;

	count_type size() { return file->size(); }

	void copy_selection(position p);
	count_type remove_selection(position p);
	count_type paste_selection(position p);
};


//// 	Editor
#define ESC 27
#define ENTER 10
#define BS 127
#define adds(s) addstr(s.c_str())
enum mode_type { INSERT, NORMAL, SELECT };
struct find_result { bool found; position pos; };

class Editor{
	// Editor state
	mode_type mode;
	position cur;
	count_type file_offset;

	// File
	string filename;
	Treap file;

	// Editation steps
	string last_find, last_replace;
	Selection selection;
	string current_insert;

	// Write to file
	void save();

	// Printing
	void clear_line(count_type i);
	void print_text(count_type i, string text);
	void print_current_line() { print_text(cur.r, file.get_line(file_offset + cur.r)); }
	void print_file(count_type start);

	// User input
	template <typename F>
	string get_input(string prompt, F func);
	string get_string(string prompt);
	count_type get_number(string prompt);

	// Movement
	void jump_line_end();
	void move(position p) { ::move(p.r, p.c); }
	void move_cursor(char ch);
	void jump(count_type r);
	void jump(position p) { jump(p.r); cur.c = p.c; }
	
	// Find and replace
	find_result find(string text);
	void replace(position p, count_type length, string text);

public:
	Editor(string _filename, Treap &_file) {
		mode = NORMAL;
		cur = {0, 0};
		file_offset = 0;

		filename = _filename;
		file = _file;

		selection = Selection(&file);
		current_insert = "";
		print_file(0);
	}

	// The big function
	bool take_action();
};