#include "io.h"

#include "utils.h"
#include "memory.h"

#include <errno.h>
#include <assert.h>
#include <dirent.h>
#include <string.h>

StringView path_concat_ss(StringPool *sp, StringView* a, StringView* b)
{
  if(a == NULL) DIE("a must be a valid string!");
  if(b == NULL) DIE("b must be a valid string!");
  if(a->len <= 0 || b->len <= 0) DIE("a and b must not be empty! (a:%d, b:%d)", a->len, b->len);
  if(a->buf[a->len - 1] == '/')
    return string_createcat_ss(sp, a, b);
  StringView slash = (StringView){.buf = "/", .len = 1};
  StringView ts = string_createcat_ss(sp, a, &slash);
  return string_createcat_ss(sp, &ts, b);
}

// Utilize DFS for recursive directory search.
size_t dir_get_recursive(DirOpContext* doc, StringView* p)
{
  assert(doc != NULL);
    
  if(p == NULL) DIE("p cannot be null!");
  if(p->len <= 0) DIE("p must not be empty!");
  
  DIR* d = opendir(p->buf);
  if(d == NULL) DIE("could not open directory!");

  size_t count = 0;
  while(d)
  {
    errno = 0;
    struct dirent* de = readdir(d);
    
    if(de == NULL && errno != 0) DIE("failed to read directory: \"%s\"", p);
    if(de == NULL) break;
    
    if(de->d_type != DT_DIR && de->d_type != DT_REG) continue;
    if(strcmp(de->d_name, ".") == 0 || strcmp(de->d_name, "..") == 0 || strcmp(de->d_name, ".git") == 0) continue;
    
    StringView res = (StringView){.buf = de->d_name, strlen(de->d_name)};
    StringView fpath = path_concat_ss(doc->sp, p, &res);
    DirEntry* file = (DirEntry*)arena_alloc(doc->a_f, sizeof(DirEntry));
    file->path = fpath;
    file->type = de->d_type;
    count++;
    
    switch(de->d_type)
    {
    case DT_REG:
      LOG_DEBUG("Added entry: \"%.*s\" to memory location @ %p.", fpath.len, fpath.buf, file);
      break;
    case DT_DIR:
      LOG_DEBUG("Added directory directory entry \"%.*s\" to memory location @ %p. Entering directory...", fpath.len, fpath.buf, file);
      count += dir_get_recursive(doc, &fpath);
      break;
    default:
      continue;
    }
  }
  LOG_DEBUG("Directory complete: %s", p->buf);
  closedir(d);
  return count;
}