8.cpp

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

class Customer {
    public :
        char Name[20] ;
        int Age ;
        char Category[20] ;
        char Product[20] ;
        float Price ;
    public : 
        void GetCustomerInfo( char StrMode[ 50 ] ) ;
} ;

class FileHandler {
    public :
        FILE *fp ;
        char FilePath[ 100 ] ;
        Customer C[ 500 ] ;
        int MaxCustomer ;
    public :
        FileHandler( char FilePath[ 100 ] ) ;
        void GetFilePath() ;
        void ReadFile() ;
        void SelectMode() ;
} ;

int main() {
    FileHandler *F = new FileHandler( "output/customer.csv" ) ;
    while( 1 ) F->SelectMode() ;
    return 0;
}

void FileHandler :: SelectMode() {
    int Mode = 0 ;
    printf( "Select Mode : " ) ;
    scanf( "%d", &Mode ) ;

    if( Mode == 0 ) { //Exit
        printf("Thank you!.\n");
        exit(0);
    } else if( Mode == 1 ) { //Who bought higest price
        float maxPrice = 0;
        int index = -1;
        for (int i = 1; i <= this->MaxCustomer; i++) {
            if (this->C[i].Price > maxPrice) {
                maxPrice = this->C[i].Price;
                index = i;
            }
        }
        if (index != -1) {
            this->C[index].GetCustomerInfo("Who bought highest price");
        } else {
            printf("No data found.\n");
        }
    } else if( Mode == 2 ) { //Lines of file
        printf( "File data = %d records.\n", this->MaxCustomer) ;
    } else if( Mode == 3 ) { //Average Price
        float totalPrice = 0;
        for (int i = 0; i < this->MaxCustomer; i++) {
            totalPrice += this->C[i].Price;
        }
        float averagePrice = totalPrice / this->MaxCustomer;
        printf("Average price = %.2f\n", averagePrice);
    } else if( Mode == 4 ) { //Count People who age above average.
        int totalAge = 0;
        for (int i = 0; i < this->MaxCustomer; i++) {
            totalAge += this->C[i].Age;
        }
        float averageAge = (float)totalAge / this->MaxCustomer;
        int count = 0;
        for (int i = 0; i < this->MaxCustomer; i++) {
            if (this->C[i].Age > averageAge) {
                count++;
            }
        }
        printf("Average age = %.2f.\n", averageAge);
        printf("People who aged above average = %d.\n", count);
    } else if( Mode == 5 ) { //Most Popular Product
        int maxCount = 0;
        char popularProduct[20] = "";
        for (int i = 0; i < this->MaxCustomer; i++) {
            int count = 0;
            for (int j = 0; j < this->MaxCustomer; j++) {
                if (strcmp(this->C[i].Product, this->C[j].Product) == 0) {
                    count++;
                }
            }
            if (count > maxCount) {
                maxCount = count;
                strcpy(popularProduct, this->C[i].Product);
            }
        }
        printf("Most popular product = %s (sold %d times).\n", popularProduct, maxCount);
    } else if( Mode == 6 ) { //Least Popular Product
        int minCount = this->MaxCustomer;
        char leastPopularCategory[20] = "";
        for (int i = 0; i < this->MaxCustomer; i++) {
            int count = 0;
            for (int j = 0; j < this->MaxCustomer; j++) {
                if (strcmp(this->C[i].Category, this->C[j].Category) == 0) {
                    count++;
                }
            }
            if (count < minCount) {
                minCount = count;
                strcpy(leastPopularCategory, this->C[i].Category);
            }
        }
        printf("Least popular category = %s (sold %d times).\n", leastPopularCategory, minCount);
    } else {
        printf("Thank you!.\n");
        exit(0);
    }
}

FileHandler :: FileHandler( char FilePath[ 100 ] ) {
    strcpy( this->FilePath, FilePath ) ;
    this->ReadFile() ;
}

void FileHandler :: ReadFile() {
    this->fp = fopen(this->FilePath, "r");
    if (this->fp == NULL) {
        printf("Error opening file.\n");
        exit(1);
    }

    char buffer[1024];
    int row = 0;
    int column = 0;
    this->MaxCustomer = 0;

    while (fgets(buffer, 1024, this->fp)) {
        column = 0;
        row++;

        if (row == 0) continue; // Skip header

        char *value = strtok(buffer, ",");
        while (value) {
            if (column == 0) {
                strcpy(this->C[this->MaxCustomer].Name, value);
            } else if (column == 1) {
                this->C[this->MaxCustomer].Age = atoi(value);
            } else if (column == 2) {
                strcpy(this->C[this->MaxCustomer].Category, value);
            } else if (column == 3) {
                strcpy(this->C[this->MaxCustomer].Product, value);
            } else if (column == 4) {
                this->C[this->MaxCustomer].Price = atof(value);
            }
            value = strtok(NULL, ",");
            column++;
        }
        this->MaxCustomer++;
    }
    fclose(this->fp);
}

void Customer :: GetCustomerInfo( char StrMode[ 50 ] ) {
    printf( "--------| %-8s\n", StrMode ) ;
    printf("%-8s : %-10s\n", "Name", this->Name ) ; 
    printf("%-8s : %-4d\n", "Age", this->Age ) ;
    printf("%-8s : %-10s\n", "Category", this->Category ) ; 
    printf("%-8s : %-10s\n", "Product", this->Product ) ; 
    printf("%-8s : %-5.2f\n", "Price", this->Price ) ; 
}

void FileHandler :: GetFilePath() {
    printf("File Path: %s\n", this->FilePath);
}