#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <string.h>
#include <curses.h>

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

/* TODO: clean up, do defines or whatever */
void map_to_bmp(Map map, size_t map_width, size_t map_height, Position start, Position goal, Path path, char **visited, char *filename) {
    /* Dimensions of the resulting image */
    int32_t width = map_width;
    int32_t height = map_height;
    uint16_t bitcount = 24;

    /* Width of a single row in bytes */
    int width_in_bytes = ((width * bitcount + 31) / 32) * 4;

    /* Size in bytes of the image, without the header */
    uint32_t imagesize = width_in_bytes * height;

    /* Size of the info header */
    const uint32_t biSize = 40;

    /* Bitmap bit offset */
    const uint32_t bfOffBits = 54;

    /* Size in bytes of resulting BMP */
    uint32_t filesize = 54 + imagesize;

    /* No. of planes */
    const uint16_t biPlanes = 1;

    /* The header */
    unsigned char header[54] = { 0 };
    memcpy(header, "BM", 2);
    memcpy(header + 2 , &filesize, 4);
    memcpy(header + 10, &bfOffBits, 4);
    memcpy(header + 14, &biSize, 4);
    memcpy(header + 18, &width, 4);
    memcpy(header + 22, &height, 4);
    memcpy(header + 26, &biPlanes, 2);
    memcpy(header + 28, &bitcount, 2);
    memcpy(header + 34, &imagesize, 4);

    /* The buffer for image data */
    unsigned char* buf = malloc(imagesize);

    /* Draw the walls */
    for(int row = height - 1; row >= 0; row--)
    {
        for(int col = 0; col < width; col++)
        {
            if (map[height - 1 - row][col] == WALL) {
                buf[row * width_in_bytes + col * 3 + 0] = 255; /* b */
                buf[row * width_in_bytes + col * 3 + 1] = 255; /* g */
                buf[row * width_in_bytes + col * 3 + 2] = 255; /* r */
            } else if (visited != NULL && visited[height - 1 - row][col]) {
                buf[row * width_in_bytes + col * 3 + 0] = 0;   /* b */
                buf[row * width_in_bytes + col * 3 + 1] = 255; /* g */
                buf[row * width_in_bytes + col * 3 + 2] = 0;   /* r */
            } else {
                buf[row * width_in_bytes + col * 3 + 0] = 0;   /* b */
                buf[row * width_in_bytes + col * 3 + 1] = 0;   /* g */
                buf[row * width_in_bytes + col * 3 + 2] = 0;   /* r */
            }
        }
    }

    /* Draw the path */
    if (path != NULL) {
        Position cur = goal;
        while (cur.x != start.x || cur.y != start.y) {
            buf[(height - cur.y - 1) * width_in_bytes + cur.x * 3 + 0] = 0;   /* b */
            buf[(height - cur.y - 1) * width_in_bytes + cur.x * 3 + 1] = 0;   /* g */
            buf[(height - cur.y - 1) * width_in_bytes + cur.x * 3 + 2] = 255; /* r */
            cur = path[cur.y][cur.x].parent;
        }
    }

    /* Start */
    buf[(height - start.y - 1) * width_in_bytes + start.x * 3 + 0] = 255; /* b */
    buf[(height - start.y - 1) * width_in_bytes + start.x * 3 + 1] = 0;   /* g */
    buf[(height - start.y - 1) * width_in_bytes + start.x * 3 + 2] = 255; /* r */

    /* Goal */
    buf[(height - goal.y - 1) * width_in_bytes + goal.x * 3 + 0] = 0;   /* b */
    buf[(height - goal.y - 1) * width_in_bytes + goal.x * 3 + 1] = 255; /* g */
    buf[(height - goal.y - 1) * width_in_bytes + goal.x * 3 + 2] = 255; /* r */


    FILE *fout = fopen(filename, "wb");
    fwrite(header, 1, 54, fout);
    fwrite((char*)buf, 1, imagesize, fout);
    fclose(fout);
    free(buf);

    message(height, "Saved to %s", filename);
    return;
}