#include "arena_alloc.h"
#include "context.h"
#include "gapbuffer.h"
#include "interp.h"
#include "mprintf.h"
#include "self.h"
#include "strbuf.h"
#include <arena.h>
#include <kb.h>
#include <liballoc.h>
#include <list.h>
#include <printf.h>
#include <stdbool.h>
#include <stddef.h>
#include <stdint.h>
#include <string.h>
#include <system.h>
#include <tcursor.h>
#include <tscreen.h>

#define LINE_INIT_MAX 40
#define PROMPT        "$ "

void* wmalloc (void* ctx, size_t size) {
  (void)ctx;
  return malloc (size);
}

void* wrealloc (void* ctx, void* mem, size_t old, size_t new) {
  (void)ctx, (void)old;
  return realloc (mem, new);
}

void wfree (void* ctx, void* mem) {
  (void)ctx;
  free (mem);
}

void* warena_malloc (void* ctx, size_t size) {
  struct arena* a = ctx;
  return arena_malloc (a, size);
}

void* warena_realloc (void* ctx, void* mem, size_t old, size_t new) {
  struct arena* a = ctx;
  return arena_realloc (a, mem, old, new);
}

void warena_free (void* ctx, void* mem) { (void)ctx, (void)mem; }

struct edit_line {
  struct gapbuffer gb;
  size_t cursor;
};

static void exec_line (const char* line) {
  struct list_node_link* tokens = NULL;

  tokenize (&tokens, line);

  if (tokens != NULL)
    parse_and_execute (tokens);
}

void app_main (void) {
  e_pid = get_exec_pid ();
  e_pgid = get_procgroup (e_pid);

  struct edit_line edit_line;

  const char* render = NULL;

  while (interp_is_running ()) {
    gapbuffer_init (&warena_malloc, &arena, &edit_line.gb, LINE_INIT_MAX);
    edit_line.cursor = 0;

    mprintf (PROMPT);

    uint8_t ch = 0;
    for (;;) {
      mail_receive (&ch, 1);

      if (ch == '\n')
        break;

      gapbuffer_move (&edit_line.gb, edit_line.cursor);

      switch (ch) {
      case '\b':
        if (edit_line.cursor > 0) {
          edit_line.cursor--;
          gapbuffer_backspace (&edit_line.gb);

          mprintf (ANSIQ_CUR_LEFT (1));

          char* tail =
              gapbuffer_string_at (&warena_malloc, &arena, &edit_line.gb, edit_line.cursor);
          mprintf ("%s" ANSIQ_SCR_CLR2LEND, tail);

          int move_back = strlen (tail);
          if (move_back > 0)
            mprintf (ANSIQ_DYN_CUR_LEFT, move_back);
        }
        break;
      case KB_DELETE:
        if (edit_line.cursor < gapbuffer_length (&edit_line.gb)) {
          edit_line.gb.gap_end++;

          char* tail =
              gapbuffer_string_at (&warena_malloc, &arena, &edit_line.gb, edit_line.cursor);
          mprintf ("%s" ANSIQ_SCR_CLR2LEND, tail);

          int move_back = strlen (tail);
          if (move_back > 0)
            mprintf (ANSIQ_DYN_CUR_LEFT, move_back);
        }
        break;
      case KB_LEFT:
        if (edit_line.cursor > 0) {
          edit_line.cursor--;
          mprintf (ANSIQ_CUR_LEFT (1));
        }
        break;
      case KB_RIGHT:
        if (edit_line.cursor < gapbuffer_length (&edit_line.gb)) {
          edit_line.cursor++;
          mprintf (ANSIQ_CUR_RIGHT (1));
        }
        break;
      default:
        if (isprint (ch)) {
          gapbuffer_insert (&warena_realloc, &arena, &edit_line.gb, ch);
          edit_line.cursor++;

          if (edit_line.cursor == gapbuffer_length (&edit_line.gb)) {
            mprintf ("%c", ch);
          } else {
            char* tail =
                gapbuffer_string_at (&warena_malloc, &arena, &edit_line.gb, edit_line.cursor - 1);
            size_t move_back = strlen (tail) - 1;
            mprintf ("%s" ANSIQ_DYN_CUR_LEFT, tail, move_back);
          }
        }
        break;
      }
    }

    mprintf ("\n");

    render = gapbuffer_get_string (&warena_malloc, &arena, &edit_line.gb);

    if (render != NULL)
      exec_line (render);

    gapbuffer_fini (&warena_free, &arena, &edit_line.gb);
    arena_reset (&arena);
  }

  arena_destroy (&arena);
}