#include <devices.h>
#include <in_input.h>
#include <mprintf.h>
#include <process_self.h>
#include <status.h>
#include <str_status.h>
#include <strconv.h>
#include <string.h>
#include <system.h>

#define COMMAND_MAX 32

struct dos_pte {
  uint8_t drive_attrs;
  uint8_t chs_start_addr[3];
  uint8_t part_type;
  uint8_t chs_last_sect_addr[3];
  uint32_t start_lba;
  uint32_t sector_count;
} __attribute__ ((packed));

struct dos_mbr {
  uint8_t boot_code[440];
  uint8_t signature[4];
  uint8_t resv[2];
  struct dos_pte ptes[4];
  uint8_t valid_sign[2];
} __attribute__ ((packed));

static void start_part_dos (void) {
  char dev_name[64];
  memset (dev_name, 0, sizeof (dev_name));
  struct dos_mbr mbr;
  memset (&mbr, 0, sizeof (mbr));
  char confirm_buf[4];
  memset (confirm_buf, 0, sizeof (confirm_buf));
  bool ok = false, write = false;

  in_stream_read_line ("Device name: ", dev_name, sizeof (dev_name));

#define prompt_partition(N)                                                                        \
  char p##N##_start_lba_str[12], p##N##_sector_cout_str[12];                                       \
  uint32_t p##N##_start_lba, p##N##_sector_count;                                                  \
  mprintf ("\nConfigure parition %d:\n", N);                                                       \
  in_stream_read_line ("Start LBA: ", p##N##_start_lba_str, sizeof (p##N##_start_lba_str));        \
  in_stream_read_line ("Sector count: ", p##N##_sector_cout_str, sizeof (p##N##_sector_cout_str)); \
  p##N##_start_lba = str_to_uint32 (p##N##_start_lba_str);                                         \
  p##N##_sector_count = str_to_uint32 (p##N##_sector_cout_str);

  prompt_partition (0);
  prompt_partition (1);
  prompt_partition (2);
  prompt_partition (3);

  mbr.ptes[0].start_lba = p0_start_lba;
  mbr.ptes[0].sector_count = p0_sector_count;
  mbr.ptes[1].start_lba = p1_start_lba;
  mbr.ptes[1].sector_count = p1_sector_count;
  mbr.ptes[2].start_lba = p2_start_lba;
  mbr.ptes[2].sector_count = p2_sector_count;
  mbr.ptes[3].start_lba = p3_start_lba;
  mbr.ptes[3].sector_count = p3_sector_count;

  mbr.valid_sign[0] = 0x55;
  mbr.valid_sign[1] = 0xAA;

  /* clang-format off */
  mprintf ("\n\n-------------------------------------------------------\n");
  mprintf ("Current configuration (%s):\n", dev_name);
  mprintf ("Partition 0: start LBA = %u, sector count = %zu\n",mbr.ptes[0].start_lba, mbr.ptes[0].sector_count);
  mprintf ("Partition 1: start LBA = %u, sector count = %zu\n",mbr.ptes[1].start_lba, mbr.ptes[1].sector_count);
  mprintf ("Partition 2: start LBA = %u, sector count = %zu\n",mbr.ptes[2].start_lba, mbr.ptes[2].sector_count);
  mprintf ("Partition 3: start LBA = %u, sector count = %zu\n",mbr.ptes[3].start_lba, mbr.ptes[3].sector_count);
  /* clang-format on */

  in_stream_read_line ("\nDoes this look plausible? [yes/no]: ", confirm_buf, sizeof (confirm_buf));

  if (strcmp (confirm_buf, "yes") == 0) {
    in_stream_read_line ("\nWrite to device? There's no going back! [yes/no]: ", confirm_buf,
                         sizeof (confirm_buf));

    ok = true;

    if (strcmp (confirm_buf, "yes") == 0) {
      write = true;
    } else {
      mprintf ("OK. Canceling\n");
    }
  } else {
    mprintf ("OK. Canceling\n");
  }

  if (ok && write) {
    size_t sector = 0;
    size_t sector_count = 1;
    int r = device_do (dev_name, XDRV_WRITE, &sector, &sector_count, &mbr, NULL);
    mprintf ("Finished writing. Result: %s (%d)\n", str_status[r < 0 ? -r : r], r);
  }
}

void app_main (void) {
  libprocess_self_init ();

  char commandbuf[COMMAND_MAX];
  commandbuf[0] = '\0';

  if (env_get (process_get_pgid (), "C", (void*)commandbuf, sizeof (commandbuf)) != ST_OK) {
    mprintf ("ERROR C=???. No command provided\n");
    return;
  }

  if (strcmp (commandbuf, "part_dos") == 0) {
    start_part_dos ();
  }
}