#include <escpos/parser.h>
#include <stdlib.h>
#include <stdio.h>
#include <assert.h>
#include <err.h>

static FILE*
fopen_or_die(const char *path, const char *mode)
{
   assert(path && mode);

   FILE *f;
   if (!(f = fopen(path, mode)))
      err(EXIT_FAILURE, "fopen(%s, %s)", path, mode);

   return f;
}

struct parser {
   struct escpos_parser parser;
   FILE *input, *output;
};

#define container_of(ptr, type, member) ((type *)((char *)(1 ? (ptr) : &((type *)0)->member) - offsetof(type, member)))

size_t
escpos_read(const struct escpos_parser *parser, void *ptr, const size_t size)
{
   assert(parser && ptr);
   const struct parser *p = container_of(parser, struct parser, parser);
   return fread(ptr, 1, size, p->input);
}

void
escpos_write(const struct escpos_parser *parser, const uint8_t *ptr, const size_t w, const size_t h)
{
   assert(parser && ptr);
   const struct parser *p = container_of(parser, struct parser, parser);
   const uint8_t header[] = { 'P', '4', '\n' };
   fwrite(header, 1, sizeof(header), p->output);
   fprintf(p->output, "%zu\n", w);
   fprintf(p->output, "%zu\n", h);
   for (size_t y = 0; y < h; ++y) {
      for (size_t x = 0; x < w; x += 8) {
         uint8_t p8 = 255;
         for (uint8_t b = 0; b < 8 && x + b < w; ++b)
            p8 ^= (-(!!ptr[y * w + x + b]) ^ p8) & (1 << (7 - b));
         fwrite(&p8, 1, 1, p->output);
      }
   }
}

int
main(int argc, char *argv[])
{
   {
#define CANVAS_W 267 * 2
#define CANVAS_H 1024
      char window[4096], var[256];
      uint8_t canvas_data[CANVAS_W * CANVAS_H], print_buffer[CANVAS_W * ESCPOS_PRINT_BUFFER_MAX_HEIGHT];
      struct parser p = {
         .parser = {
            .read = escpos_read,
            .write = escpos_write,
            .canvas = { .data = canvas_data, .w = CANVAS_W, .h = CANVAS_H },
            .print_buffer = { .data = print_buffer, .w = CANVAS_W, .h = ESCPOS_PRINT_BUFFER_MAX_HEIGHT },
            .window = { .data = window, .len = sizeof(window) },
            .var = { .data = var, .len = sizeof(var) },
         },
         .input = (argc >= 2 ? fopen_or_die(argv[1], "rb") : stdin),
         .output = (argc >= 3 ? fopen_or_die(argv[2], "wb") : stdout),
      };

      if (!escpos_parser_parse(&p.parser, (argc >= 2 ? argv[1] : "stdin")))
         exit(EXIT_FAILURE);

      fclose(p.input);
      fclose(p.output);
   }

   return EXIT_SUCCESS;
}