fat-2

// Financial Account Tracker (FAT) v0.0
// Geecko, 2011

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>

typedef struct
{
  char name[16];
  int (*f)();
} Command;

typedef struct
{
  int c, i;
  char** v;
} Argument;

typedef struct
{
  int day, month, year;
  char desc[31];
  float balance;
} Operation;

char file_path[128];
Argument arg;
Operation *op = NULL;
int op_size = 0;

// Common

int checkCommand(Command cmd[], int size, char name[])
{
  int i;
  for (i=0; i<size; i++)
  {
    if (!strcmp(cmd[i].name,name)) return i;
  }
  return -1;
}


int remainingArg()
{
  return arg.c - arg.i;
}


int exec(Command cmd[], int size)
{
  int err;

  if (arg.i >= arg.c) return -1;

  err = checkCommand(cmd,size,arg.v[arg.i]);
  if (err < 0)
  {
    printf("Invalid command (%s)\n",arg.v[arg.i]);
    return 1;
  }
  arg.i++;

  err = cmd[err].f();
  if (err > 0) printf("Error arg #%d\n",arg.i+err-1);
  arg.i--;

  return 0;
}


void push(Operation t)
{
  op = realloc(op,(++op_size) * sizeof(Operation));
  op[op_size-1] = t;
}


void pop()
{
  op = realloc(op,(--op_size) * sizeof(Operation));
}


void getDCB(float* debit, float* credit, float* balance, int id)
{
  *balance = (id>0 ? op[id-1].balance : 0.f);
  *debit = 0.f;
  *credit = 0.f;

  if (op[id].balance - *balance > 0.f)
  {
    *credit = op[id].balance - *balance;
  }
  else
  {
    *debit = *balance - op[id].balance;
  }

  *balance = op[id].balance;
}


void getDMY(int* day, int* month, int* year)
{
  time_t rawTime;
  struct tm* timeInfo;
  time(&rawTime);
  timeInfo = localtime(&rawTime);

  *day = timeInfo->tm_mday;
  *month = timeInfo->tm_mon + 1;
  *year = timeInfo->tm_year + 1900;
}


void tableJoint()
{
  printf("+-------+----------+-----------------------------+---------+---------+---------+\n");
}

void tableHead()
{
  tableJoint();
  printf("|ID     |Date      |Description                  |Debit    |Credit   |Balance  |\n");
  tableJoint();
}

void tableElement(int id)
{
  float balance, credit, debit;

  if (id < 0 || id >= op_size) return;
  getDCB(&debit,&credit,&balance,id);

  printf("|%7d|%02d/%02d/%4d|%29s|",id+1,
         op[id].day,op[id].month,op[id].year,op[id].desc);

  if (credit > 0.f) printf("         |%9.2f|",credit);
  else if (debit > 0.f) printf("%9.2f|         |",debit);

  printf("%9.2f|\n",balance);
}

// File management

void load()
{
  op = NULL;
  op_size = 0;

  FILE* file = fopen(file_path,"r");
  if (file == NULL)
  {
    printf("Error opening file for reading\n");
    return;
  }

  Operation t;
  for (;;)
  {
    if (fscanf(file,"%*d %2d%2d%4d \"%[^\"]\" %f\n",
               &t.day,&t.month,&t.year,t.desc,&t.balance) <= 0) break;

    op = realloc(op,(++op_size) * sizeof(Operation));
    op[op_size-1] = t;
  }

  fclose(file);
}


void write()
{
  int i;

  FILE* file = fopen(file_path,"w");
  if (file == NULL)
  {
    printf("Error opening file for writing\n");
    return;
  }

  Operation t;
  for (i=0; i<op_size; i++)
  {
    t = op[i];
    if (fprintf(file,"%d %02d%02d%4d \"%s\" %.2f\n",
                i+1,t.day,t.month,t.year,t.desc,t.balance) <= 0) break;
  }

  fclose(file);
}

// Commands

int add()
{
  float amount;
  char desc[31] = {0};

  if (remainingArg() < 2) return remainingArg() + 1;
  if (strncpy(desc,arg.v[arg.i+0],29) <= 0) return 1;
  if (sscanf(arg.v[arg.i+1],"%f",&amount) <= 0) return 2;
  if (amount == 0.f) return 2;

  Operation t;
  getDMY(&t.day,&t.month,&t.year);
  t.balance = amount + (op_size>0 ? op[op_size-1].balance : 0);
  strcpy(t.desc,desc);
  push(t);
  write();

  printf("Adding an operation (%02d/%02d/%4d):\n",t.day,t.month,t.year);
  printf(" - ID is #%d\n",op_size);
  printf(" - Description is \"%s\"\n",desc);
  printf(" - Amount is %+.2f euro(s)\n",amount);
  printf(" - Current balance is %+.2f euro(s)\n",op[op_size-1].balance);

  return 0;
}


int delete()
{
  float old_amount, old_balance;
  char* old_desc;

  if (op_size <= 0)
  {
    printf("Nothing to delete\n");
    return 0;
  }

  old_desc = op[op_size-1].desc;
  old_balance = (op_size>1 ? op[op_size-2].balance : 0);
  old_amount = op[op_size-1].balance - old_balance;

  printf("Deleting the last operation (%02d/%02d/%4d):\n",
         op[op_size-1].day,op[op_size-1].month,op[op_size-1].year);
  printf(" - ID was #%d\n",op_size);
  printf(" - Description was \"%s\"\n",old_desc);
  printf(" - Amount was %+.2f euro(s)\n",old_amount);
  printf(" - Balance is back to %+.2f euro(s)\n",old_balance);

  pop();
  write();

  return 0;
}

int view_recap()
{
  int i;
  float balance, debit, credit, acc_debit=0.f, acc_credit=0.f;

  for (i=0; i<op_size; i++)
  {
    getDCB(&debit,&credit,&balance,i);
    acc_debit += debit;
    acc_credit += credit;
  }

  printf("Total credit: %.2f\n",acc_credit);
  printf("Total debit: %.2f\n",acc_debit);
  printf("Current balance: %.2f\n",balance);

  return 0;
}


int view_last()
{
  int i, n;

  n = 20;
  if (remainingArg() > 0)
  {
    if (sscanf(arg.v[arg.i],"%d",&n) <= 0) return 1;
  }
  if (op_size < n) n = op_size;

  if (n < 1)
  {
    printf("Nothing to print\n");
    return 0;
  }

  tableHead();
  for (i=op_size-n; i<op_size; i++) tableElement(i);
  tableJoint();

  return 0;
}


int view_id()
{
  int id;

  if (remainingArg() <= 0) return 1;
  if (sscanf(arg.v[arg.i],"%d",&id) <= 0) return 1;
  if (id < 1 || id > op_size) return 1;

  tableHead();
  tableElement(id-1);
  tableJoint();

  return 0;
}


int view_day()
{
  int i, day, month, year;

  if (remainingArg() < 3) getDMY(&day,&month,&year);
  else
  {
    if (sscanf(arg.v[arg.i+0],"%d",&day) <= 0) return 1;
    if (sscanf(arg.v[arg.i+1],"%d",&month) <= 0) return 2;
    if (sscanf(arg.v[arg.i+2],"%d",&year) <= 0) return 3;
  }

  for (i=0; i<op_size; i++)
  {
    if (op[i].day == day && op[i].month == month && op[i].year == year) break;
  }
  if (i >= op_size)
  {
    printf("Nothing to print\n");
    return 0;
  }

  tableHead();
  for (i=0; i<op_size; i++)
  {
    if (op[i].day == day && op[i].month == month && op[i].year == year)
    {
      tableElement(i);
    }
  }
  tableJoint();

  return 0;
}


int view_month()
{
  int i, day, month, year;

  if (remainingArg() < 2) getDMY(&day,&month,&year);
  else
  {
    if (sscanf(arg.v[arg.i+0],"%d",&month) <= 0) return 1;
    if (sscanf(arg.v[arg.i+1],"%d",&year) <= 0) return 2;
  }

  for (i=0; i<op_size; i++)
  {
    if (op[i].month == month && op[i].year == year) break;
  }
  if (i >= op_size)
  {
    printf("Nothing to print\n");
    return 0;
  }

  tableHead();
  for (i=0; i<op_size; i++)
  {
    if (op[i].month == month && op[i].year == year) tableElement(i);
  }
  tableJoint();

  return 0;
}


int view_year()
{
  int i, day, month, year;

  if (remainingArg() < 1) getDMY(&day,&month,&year);
  else
  {
    if (sscanf(arg.v[arg.i+0],"%d",&year) <= 0) return 1;
  }

  for (i=0; i<op_size; i++)
  {
    if (op[i].year == year) break;
  }
  if (i >= op_size)
  {
    printf("Nothing to print\n");
    return 0;
  }

  tableHead();
  for (i=0; i<op_size; i++)
  {
    if (op[i].year == year) tableElement(i);
  }
  tableJoint();

  return 0;
}


Command cmd_view[6] =
{
  {"recap",view_recap},
  {"last",view_last},
  {"id",view_id},
  {"day",view_day},
  {"month",view_month},
  {"year",view_year}
};

int view()
{
  if (exec(cmd_view,6) < 0)
  {
    printf("Financial account tracker (FAT) v0.0\n");
    printf("Usage: fat view COMMAND [ARGS]\n\n");
    printf("Commands available:\n");
    printf("   recap\n");
    printf("   last [n]\n");
    printf("   id num\n");
    printf("   day [dd mm yyyy]\n");
    printf("   month [mm yyyy]\n");
    printf("   year [yyyy]\n");
  }

  return 0;
}

// Main

Command cmd_main[3] =
{
  {"add",add},
  {"delete",delete},
  {"view",view}
};

int main(int argc, char **argv)
{
  arg.c = argc;
  arg.v = argv;
  arg.i = 1;

  strcpy(file_path,argv[0]);
  strcpy(strrchr(file_path,'/')+1,"facc");

  load();
  if (exec(cmd_main,3) < 0)
  {
    printf("Financial account tracker (FAT) v0.0\n");
    printf("Usage: fat COMMAND [ARGS]\n\n");
    printf("Commands available:\n");
    printf("   add \"desc\" amount\n");
    printf("   delete\n");
    printf("   view COMMAND [ARGS]\n");
  }

  return 0;
}