#include "../../include/database.h"
#include "../../include/package.h"
#include "../../include/error.h"
#include "../../include/util.h"

#include <sqlite3.h>
#include <strings.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <dirent.h>
#include <errno.h>
#include <stdio.h>

#define LINE_MIN   36 // keep (1) + colon (1) + MD5 hash (32) + colon (1) + path (min 1)
#define KEEP_INDEX 0
#define HASH_INDEX 2
#define PATH_INDEX 35

size_t __lm_database_files_get(lm_database_t *db, lm_entry_t *entry, char *path){
  size_t name_size = strlen(entry->name)+20;
  size_t full_size = name_size + strlen(db->dir);

  if(NULL != path){
    char files_name[name_size];
    snprintf(files_name, name_size, "%s_files", entry->name);
    join(path, db->dir, files_name);
  }

  return full_size;
}

#define __lm_files_size() __lm_database_files_get(db, entry, NULL)
#define __lm_files_path(p) __lm_database_files_get(db, entry, p)

FILE *__lm_database_files_open(lm_database_t *db, lm_entry_t *entry, char *perms){
  if(NULL == db || NULL == entry){
    lm_error_set(LM_ERR_ArgNULL);
    return false;
  }
 
  char files_path[__lm_files_size()];
  FILE *filesp = NULL;

  __lm_files_path(files_path);

  if(!exists(files_path, NULL)){
    lm_error_set(LM_ERR_DbFilesNotFound);
    return NULL;
  }

  if(NULL == (filesp = fopen(files_path, perms))){
    lm_error_set(LM_ERR_DbFilesOpenFail, files_path);
    return NULL;
  }

  return filesp;
}

char *__lm_database_files_line_single(FILE *filesp, char *path) {
  ssize_t line_len = 0;
  char *line = NULL;

  while ((line_len = getline(&line, (size_t*)&line_len, filesp)) >= LINE_MIN) {
    // keep : hash : path
    // 1    : 32   : ?
  
    // ignore empty line
    if(line[0] == 0)
      goto next;

    // remove newline
    else if (line[line_len-1] == '\n')
      line[line_len-1] = 0;

    if(eq((line + PATH_INDEX), path))
      return line;

  next:
    free(line);
    line = NULL;
    line_len = 0;
  }

  return line;
}

char *__lm_database_files_line_all(lm_database_t *db, char *path) {
  size_t dirlen = strlen(db->dir);
  struct dirent *ent = NULL;
  FILE* filesp = NULL;
  DIR *ddir = NULL;
  char *ret = NULL;

  if(NULL == (ddir = opendir(db->dir))){
    lm_error_set(LM_ERR_DbFilesDirFail, db->dir);
    goto end;
  }

  while(NULL != (ent = readdir(ddir))){
    size_t entlen = strlen(ent->d_name);
    char entpath[entlen+dirlen+10];

    join(entpath, db->dir, ent->d_name);

    if(NULL == (filesp = fopen(entpath, "r"))){
      lm_error_set(LM_ERR_DbFilesOpenFail, entpath);
      goto end;
    }

    if(NULL == (ret = __lm_database_files_line_single(filesp, path)))
      goto end;
  }

end:
  if(NULL != ddir)
    closedir(ddir);

  if(NULL != filesp)
    fclose(filesp);

  return ret;
}

ssize_t lm_database_files_count(lm_database_t *db, lm_entry_t *entry){
  if(NULL == db || NULL == entry){
    lm_error_set(LM_ERR_ArgNULL);
    return 0;
  }

  FILE *filesp = NULL;
  ssize_t count = 0;
  char c = 0;

  if((filesp = __lm_database_files_open(db, entry, "r")) == NULL)
    return 0; // error set by function

  while((c = fgetc(filesp)) != EOF)
    if(c == '\n')
      count ++;

  fclose(filesp);
  return count;
}

bool lm_database_files_contains(lm_database_t *db, lm_entry_t *entry, char *path){
  if(NULL == db || NULL == entry || NULL == path){
    lm_error_set(LM_ERR_ArgNULL);
    return false;
  }
 
  FILE *filesp = NULL;
  char *line = NULL;
  bool ret = false;

  if((filesp = __lm_database_files_open(db, entry, "r")) == NULL)
    return false; // error set by function

  if((line = __lm_database_files_line_single(filesp, path)) != NULL)
    ret = true;

  free(line);

  if(NULL != filesp)
    fclose(filesp);

  return ret;
}

bool lm_database_files_matches(lm_database_t *db, char *path, char *hash){
  if(NULL == db || NULL == path || NULL == hash){
    lm_error_set(LM_ERR_ArgNULL);
    return false;
  }
  
  char *line = NULL, *line_hash = NULL;
  bool ret = false;

  if(NULL == (line = __lm_database_files_line_all(db, path)))
    return false;

  line_hash = line+2;
  line[35] = 0;

  if(eq(line_hash, hash))
    ret = true;

  free(line);
  return ret;
}

bool lm_database_files_iskeep(lm_database_t *db, char *path){
  if(NULL == db || NULL == path){
    lm_error_set(LM_ERR_ArgNULL);
    return false;
  }

  char *line = NULL;
  bool ret = false;

  if(NULL == (line = __lm_database_files_line_all(db, path)))
    return false;

  if(line[0] == '1')
    ret = true;

  free(line);
  return ret;
}

bool lm_database_files_add(lm_database_t *db, lm_entry_t *entry, char *hash, char *path){
  if(NULL == db || NULL == entry || NULL == hash || NULL == path){
    lm_error_set(LM_ERR_ArgNULL);
    return false;
  }
  
  char files_path[__lm_files_size()];
  FILE *filesp = NULL;

  __lm_files_path(files_path);

  if(NULL == (filesp = fopen(files_path, "a"))){
    lm_error_set(LM_ERR_DbFilesOpenFail, files_path);
    return false;
  }
  
  fwrite(lm_package_data_keep_contains(entry, path) ? "1:" : "0:", 1, 2, filesp);
  fwrite(hash, 1, strlen(hash), filesp);
  fwrite(":", 1, 1, filesp);
  fwrite(path, 1, strlen(path), filesp);
  fwrite("\n", 1, 1, filesp);

  fclose(filesp);
  return true;
}

bool lm_database_files_del(lm_database_t *db, lm_entry_t *entry){
  if(NULL == db || NULL == entry){
    lm_error_set(LM_ERR_ArgNULL);
    return false;
  }

  FILE *original = NULL, *temp = NULL;
  char temp_name[strlen(entry->name)+15];
  char temp_path[__lm_files_size()+10];
  char real_path[__lm_files_size()], *line = NULL;
  bool ret = false, empty = true;
  ssize_t line_len = 0;

  __lm_files_path(real_path);
  sprintf(temp_name, "%s_files.temp", entry->name);
  join(temp_path, db->dir, temp_name);

  if(NULL == (original = fopen(real_path, "r"))){
    lm_error_set(LM_ERR_DbFilesOpenFail, real_path);
    goto end;
  }
  
  if(NULL == (temp = fopen(temp_path, "a"))){
    lm_error_set(LM_ERR_DbFilesOpenFail, temp_path);
    goto end;
  }

  while ((line_len = getline(&line, (size_t*)&line_len, original)) >= LINE_MIN){
    if(line[0] == '1'){
      fwrite(line, 1, line_len, temp);
      empty = false;
    }

    free(line);
    line = NULL;
    line_len = 0;
  }

  ret = true;
end:
  if(NULL != original)
    fclose(original);

  if(NULL != temp)
    fclose(temp);

  free(line);

  if(ret && unlink(real_path) != 0){
    lm_error_set(LM_ERR_DbFilesUnlinkFail, real_path);
    ret = false;
  }

  if(empty || !ret){
    unlink(temp_path);
  }

  else if(ret && rename(temp_path, real_path) != 0){
    lm_error_set(LM_ERR_DbFilesRenameFail, real_path);
    ret = false;
  }

  return ret;
}

bool lm_database_files_del_all(lm_database_t *db, lm_entry_t *entry){
  if(NULL == db || NULL == entry){
    lm_error_set(LM_ERR_ArgNULL);
    return false;
  }
 
  char files_path[__lm_files_size()];
  __lm_files_path(files_path);

  if(exists(files_path, NULL) && unlink(files_path) != 0){
    lm_error_set(LM_ERR_DbFilesUnlinkFail, files_path);
    return false;
  }

  return true;
}

bool lm_database_files_next(lm_database_t *db, lm_entry_t *entry, char **path, char **hash, bool *keep){
  if(NULL == db || NULL == entry || NULL == path || NULL == hash || NULL == keep){
    lm_error_set(LM_ERR_ArgNULL);
    return false;
  }

  if(NULL == db->filesp && NULL == (db->filesp = __lm_database_files_open(db, entry, "r")))
    return false; // error set by function

  ssize_t line_len = 0;
  char *line = NULL;

  if(NULL != *hash)
    free(*hash-HASH_INDEX);

  if((line_len = getline(&line, (size_t*)&line_len, db->filesp)) <= LINE_MIN)
    goto eof;

  if(line[line_len-1] == '\n')
    line[line_len-1] = 0; // replace newline with null terminator 
  line[PATH_INDEX-1] = 0; // replace colon with null terminator

  *keep = line[0] == '1';
  *hash = line + HASH_INDEX;
  *path = line + PATH_INDEX;

  return true;

eof:
  fclose(db->filesp);
  free(line);

  db->filesp = NULL;
  *keep = false;
  *path = NULL;
  *hash = NULL;

  return false;
}

void lm_database_files_next_free(lm_database_t *db, lm_entry_t *entry, char **path, char **hash, bool *keep){
  if(NULL == db || NULL == entry || NULL == path || NULL == hash || NULL == keep){
    lm_error_set(LM_ERR_ArgNULL);
    return;
  }

  if(NULL != db->filesp)
    fclose(db->filesp);

  if(NULL != *hash)
    free(*hash-HASH_INDEX);

  db->filesp = NULL;
  *keep = false;
  *path = NULL;
  *hash = NULL;
}