#include "namesarchive.h"
#include <stdlib.h>
#include <stdio.h>
#include <string.h>

#define INDEX_NOT_FOUND -1

typedef struct
{
    char name[MAX_NAME_LEN+1];
    unsigned int id;
} Student;

Student students[MAX_NAMES];
unsigned int numberOfEntries = 0;

int addStudent(const char *name, unsigned int id)
{
    if(numberOfEntries < MAX_NAMES)
    {
        strncpy(students[numberOfEntries].name, name, MAX_NAME_LEN+1);
        students[numberOfEntries].name[MAX_NAME_LEN] = '\0';
        students[numberOfEntries].id = id;
        numberOfEntries++;
        return 1;
    }

    return 0;
}

void printStudents()
{
    for(int i = 0; i < numberOfEntries; i++)
    {
        printf("%s: %u\n", students[i].name, students[i].id);
    }
}

static int getNameIdx(const char *name)
{
    for(int i = 0; i < numberOfEntries; i++)
    {
        if(strcmp(name, students[i].name) == 0)
            return i;
    }
    return INDEX_NOT_FOUND;
}

static void removeAt(int idx)
{
    for(int i = idx; i < numberOfEntries-1; i++)
    {
        students[i] = students[i+1];
    }
    numberOfEntries--;
}

Status removeStudent(const char *name)
{
    int idx = getNameIdx(name);

    if(idx == INDEX_NOT_FOUND)
    {
        return REMOVE_ERROR;
    }
    else
    {
        removeAt(idx);
        return STATUS_OK;
    }
}

static int compareStudents(const void *arg1, const void *arg2)
{
    const Student *student1 = (const Student *)arg1;
    const Student *student2 = (const Student *)arg2;

    int nameDiff = strcmp(student1->name, student2->name);

    if(nameDiff == 0)
        return student1->id - student2->id;
    else
        return nameDiff;
}

void sortStudents()
{
    qsort(students, numberOfEntries, sizeof(Student), compareStudents);
}