#include <curses.h>
#include <signal.h>
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <unistd.h>
#include <time.h>

#include "map.h"
#include "structs.h"
#include "config.h"
#include "error.h"
#include "priority_queue.h"
#include "path.h"

/* So, TODO for now:
   - Keybinds to increase map size
   - Allow maps to have costs
   - Implement greedy-best-first algorithm (4 and 8 dir)
   - Implement Dijkstra algorithm (4 and 8 dir)
   - Implement the A* algorithm (4 and 8 dir)
   - MORE MAPS FOR THE MAP PEOPLE
   - Implement controls (to change maps, move start/goal, etc.)
   - Clean up unused `#include`s 
   - mouse controls to edit map, drag start and end around */

void sigint_handler(int sig) {
    (void)sig; /* We know it's a SIGINT */
    endwin();
    printf("Received SIGINT\n");
    exit(1);
}

void initialize_colors(void) {
    start_color();
    use_default_colors();
    init_pair(EMPTY_COLOR, COLOR_BLACK, -1);
    init_pair(VISITED_COLOR, COLOR_GREEN, COLOR_GREEN);
    init_pair(GOAL_COLOR, -1, COLOR_RED);
    init_pair(WALL_COLOR, COLOR_WHITE, COLOR_WHITE); 
    init_pair(START_COLOR, -1, COLOR_RED);
    init_pair(PATH_COLOR, COLOR_RED, COLOR_RED);
    init_pair(FRONTIER_COLOR, COLOR_BLUE, COLOR_BLUE);
    init_pair(CURSOR_COLOR, -1, COLOR_RED);
}

void init_ncurses(void) {
    initscr();     /* Initialize the ncurses screen */
    cbreak();      /* Process input one char at a time */
    curs_set(0);   /* Hide the cursor */
    noecho();      /* Don't echo characters */
    initialize_colors();
}

int main(int argc, char **argv) {
    Position start_pos, end_pos;
    size_t width, height;
    Map map = NULL;

    size_t mwidth = 20;  /* Maze width  */
    size_t mheight = 10; /* Maze height */

    char is_maze = 0;
    char anim = 0;
    int dirs = 8;

    srand(time(NULL));
    
    /* Handle args.
     * Currently supported:
     *  -a to animate the pathfinding (get input after each step)
     *  -m {width}x{height} to give a maze of given size
     *  -f {filename} to load a map from the filename
     *  -4 for four directions
     *  -8 for eight directions */
    /* TODO: Argument to choose the algorithm */
    int opt;
    while ((opt = getopt(argc, argv, ":am:f:48")) != -1) {
        switch (opt) {
            case 'a': anim = 1; break;
            case 'm':
                      if (sscanf(optarg, "%zux%zu", &mwidth, &mheight) != 2) error("Wrong maze size string in argument\n");
                      is_maze = 1;
                      map = rbt_maze_map(mwidth, mheight, (unsigned int) time(NULL));
                      start_pos.x = 0;
                      start_pos.y = 0;
                      height = mheight * 2 - 1;
                      width = mwidth * 2 - 1;
                      end_pos.x = width - 1;
                      end_pos.y = height - 1;
                      break;
            case 'f':
                      map = file_plaintext_map(optarg, &width, &height, &start_pos, &end_pos);
                      break;
            case '4': dirs = 4; break;
            case '8': dirs = 8; break;
            case '?': error("Unknown option: %c\n", optopt);
            case ':': error("Option %c requires an argument\n", optopt);
        }
    }
    if (map == NULL) { /* If no map were given */
        is_maze = 1;
        if (argc == 4) { /* maze size as argv[2] and [3] */
            mwidth = atoi(argv[2]);
            mheight = atoi(argv[3]);
        }
        map = rbt_maze_map(mwidth, mheight, rand());
        start_pos.x = 0;
        start_pos.y = 0;
        height = mheight * 2 - 1;
        width = mwidth * 2 - 1;
        end_pos.x = width - 1;
        end_pos.y = height - 1;
    }

    signal(SIGINT, sigint_handler);

    init_ncurses();

    int offset_x = 0, offset_y = 0;

    draw_map(map, width, height, offset_x, offset_y, start_pos, end_pos, NULL, NULL, NULL, NULL);
    //print_map_out(map, width, height);

    char visited[height][width];
    Path path = NULL;
    path = breadth_first_search_path(dirs, map, width, height, start_pos, end_pos, visited, anim);

    while (1) {
        draw_map(map, width, height, offset_x, offset_y, start_pos, end_pos, NULL, path, visited, NULL);
        char c = getch();
        switch (c) {
            case 'h': offset_x -= 2; break;
            case 'l': offset_x += 2; break;
            case 'j': offset_y += 1; break;
            case 'k': offset_y -= 1; break;
            case 'a': anim = !anim; break;
            case 'n': 
                      if (is_maze) { 
                          map_free(map, height);
                          map = rbt_maze_map(mwidth, mheight, rand());
                          path_free(path, height);
                          path = breadth_first_search_path(dirs, map, width, height, start_pos, end_pos, visited, anim);
                      }
                break;
            case 'q': map_free(map, height); path_free(path, height); endwin(); return 0;
        }
    }

    endwin();
    return 0;
}