KR

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#define EOL '\n'

typedef struct chat chat;
typedef struct active active;

struct chat {
    char *date;
    char *client;
    char *protocol;
    char *user;
    char *message;
    chat *next;
};

struct active {
    char *user;
    char *message;
    int messageLength;
    int occur;
    active *next;
};

void menuShow(int *choosePoint);
char *readLine(FILE *file);
void cutTime(char *str, size_t cutpos, size_t cutlen);
char *splitLine(FILE *fp, char endC);
void mostActiveUser(chat *ptrHead);
int addNode(chat** current,FILE *fp1);
int fillData(FILE *fp1 , chat **elem,int *ch);
void deleteByUser(chat** head, char* user);
void userMood(chat** head, char* user);
void printList(chat* head);
void string_acquire(char *s,int size);
int main() {
    chat *head = NULL;
    chat *current = NULL;
    int length;
    FILE *fp,*fp1;
    char file_name[12];
    printf("Enter file name:\n");
    string_acquire(file_name,12);
    fp = fopen(file_name,"r"); //TODO: user input file name
    fp1 = fopen("history.db","w+");
    if ((!fp) || (!fp1)) {
        fprintf(stderr,"Error opening file!\n");
        exit(1);
    }
    char *line;
    while(!feof(fp)) {
        line = readLine(fp);
        cutTime(line, 11, 9);
        fprintf(fp1,"%s\n",line);
        printf("LOG: write a line to database: %s\n", line);
        free(line);
    }
    fclose(fp);

    rewind(fp1);
    fseek(fp1, 1, SEEK_SET);
    addNode(&head,fp1);
    current = head;
    while(1) {  //filler
        if (!addNode(&current,fp1)) break;
    }
    fclose(fp1);
    //MENU
    int choose = 0;
    char user_name[12];
    menuShow(&choose);
    switch(choose) {
        case 1:
            printf("Enter username: ");
            string_acquire(user_name,12);
            deleteByUser(&head, user_name);
            printf("Users left:\n");
            printList(head);
            break;
        case 2:
            printf("Enter username: ");
            string_acquire(user_name,12);
            userMood(&head, user_name);
            break;
        case 3:
            mostActiveUser(head);
            break;
        case 4:
            return 0;
        default:
            break;
    }

    free(head);
    free(current);

    return 0;
}

void string_acquire(char *s,int size){
    int i;
    fflush(stdin);
    fgets(s,size,stdin);
    i=strlen(s)-1;
    if(s[i]!='\n') while(getchar()!='\n');
    if(s[i]=='\n') s[i]='\0';
}

void menuShow(int *choosePoint) {
    int k = -1;
    do {
        printf("\n1.Deleting all messages from a given user.\n");
        printf("\n2.Find out what is the mood of a given user.\n");
        printf("\n3.Display the most active user(s)\n");
        printf("\n4.EXIT\n");
        printf("Please enter your option: ");
        k = scanf("%d", &(*choosePoint));
    } while ((k != 1) && ((*choosePoint) < 1) && ((*choosePoint) > 4));

}

void printList(chat* head) {
    while(head) {
        printf("\n");
        printf("%s\n", head->user);
        head = head->next;
    }
}

void deleteByUser(chat** head, char* user) {
    chat* temp = *head;
    chat* node = NULL;
    while(temp) {
        if(strcmp(temp->user, user) == 0) {
            if(temp == *head) {
                *head = (*head)->next;
                free(temp);
                temp = *head;
            } else {
                node->next = temp->next;
                free(temp);
                temp = node; //->next;
            }
        }

        if(temp == NULL) {
            break;
        }

        node = temp;
        temp = temp->next;
    }
}

void userMood(chat** head, char* user) {
    const char* message , *lastFind = NULL , *ptr;
    int sad = 0, happy = 0;
    double mood;
    chat* temp = *head;

    while(temp) {
        if(strcmp(temp->user, user) == 0) {
            message = temp->message;

            for(ptr=message; (lastFind=strstr(ptr, ":)")); ptr=lastFind+1) happy++;
            for(ptr=message; (lastFind=strstr(ptr, ":D")); ptr=lastFind+1) happy++;
            for(ptr=message; (lastFind=strstr(ptr, "=]")); ptr=lastFind+1) happy++;
            for(ptr=message; (lastFind=strstr(ptr, ":P")); ptr=lastFind+1) happy++;
            for(ptr=message; (lastFind=strstr(ptr, ":(")); ptr=lastFind+1) sad++;
            for(ptr=message; (lastFind=strstr(ptr, ":'(")); ptr=lastFind+1) sad++;
            for(ptr=message; (lastFind=strstr(ptr, "=(")); ptr=lastFind+1) sad++;

        }
        temp = temp->next;
        if(temp == NULL) break;
    }
    mood = happy/sad;
    if (mood > 1.5) printf("%s is happy!\n",user);
    else if (mood < 0.5) printf("%s is sad!\n",user);
    else printf("%s is neutral!\n",user);
}

void mostActiveUser(chat *ptrHead) {

    chat *row;
    row = ptrHead;
    active *person = NULL, *temp, *prev;
    while(row!=NULL) {
        temp = person;
        while(temp != NULL && strcmp(temp->user,row->user) != 0) {
            prev = temp;
            temp = temp->next;
        }

        if(temp == NULL) {
            temp = (active*)malloc(sizeof(active));
            temp->user = row->user;
            temp->message = row->message;
            temp->messageLength = strlen(temp->message);
            temp->occur = 1;
            temp->next = NULL;
            if(person!=NULL) {
                prev->next=temp;
            } else {
                person = temp;
            }
        } else {
            temp->message = row->message;
            temp->messageLength += strlen(temp->message);
            temp->occur += 1;
        }
        row = row->next;
    }

    active *most_ocurrences = NULL;
    active *most_messages = NULL;

    while(person!=NULL) {
        if(most_ocurrences == NULL) {
            most_ocurrences = person;
        } else if(most_ocurrences-> occur < person->occur) {
            most_ocurrences = person;
        }

        if(most_messages == NULL) {
            most_messages = person;
        } else if(most_messages->messageLength < person->messageLength) {
            most_messages = person;
        }
        person = person->next;
    }

    printf("%s is the user with most total messages posted : %d\n", most_ocurrences->user, most_ocurrences->occur);
    printf("%s is the user with most total symbols written : %d\n", most_ocurrences->user, most_ocurrences->messageLength);
    free(person);
}

int addNode(chat** current,FILE *fp1) {
    int check , ch;
    chat *temp = malloc(sizeof(chat));
    check = fillData(fp1, &temp,&ch);
    temp->next = NULL;
    if(*current == NULL) {
        *current = temp;
    } else {
        (*current)->next = temp;
        (*current) = (*current)->next;
    }

    if (!check) return 0;
    return 1;
}

int fillData(FILE *fp1 , chat **elem,int *ch) {
        (*elem)->date = splitLine(fp1, ']');
        fseek(fp1,2,SEEK_CUR);
        (*elem)->client = splitLine(fp1, '.');

        (*elem)->protocol = splitLine(fp1, ']');

        fseek(fp1, 1, SEEK_CUR);
        (*elem)->user = splitLine(fp1, ':');

        fseek(fp1, 1, SEEK_CUR);
        (*elem)->message = splitLine(fp1, EOL);
        if (((*ch) = fgetc(fp1)) == EOF) { //proverka za EOF i EOL escaping (+1byte)
            return 0;
        }
        return 1;
}

char *readLine(FILE *file) {

    if (file == NULL) {
        printf("Error: file pointer is null.");
        exit(1);
    }

    int maximumLineLength = 128;
    char *lineBuffer = (char *)malloc(sizeof(char) * maximumLineLength);

    if (lineBuffer == NULL) {
        printf("Error allocating memory for line buffer.");
        exit(1);
    }

    char ch = getc(file);
    int count = 0;

    while ((ch != EOL) && (ch != EOF)) {
        if (count == maximumLineLength) { //refill
            maximumLineLength += 128;
            lineBuffer = realloc(lineBuffer, maximumLineLength);
            if (lineBuffer == NULL) {
                printf("Error reallocating space for line buffer.");
                exit(1);
            }
        }
        lineBuffer[count++] = ch;
        ch = getc(file);
    }

    lineBuffer[count] = '\0'; //osvobojdavam sled obrabotkata v main funkciqta
    realloc(lineBuffer, count + 1);
    if (lineBuffer == NULL) {
        printf("Error allocating memory for line buffer.");
        exit(1);
    }
    return lineBuffer;
}

void cutTime(char *str, size_t cutpos, size_t cutlen) {
  size_t len;
  len = strlen(str);
  memmove( str+cutpos, str+cutpos+cutlen, 1+len - cutpos - cutlen);
}

char *splitLine(FILE *fp, char endC) {
    char *string;
    size_t len = 10;
    int cnt = 0;
    char c;
    if(!( string = (char*) malloc(len) )) {
        printf("Error allocating memory for line buffer.");
        exit(1);
    }

    while((c = fgetc(fp)) != endC)
    {
        if(c == EOF)
        {
            free(string);
            return NULL;
        }

        if(cnt>=len-1)
            string = (char *) realloc(string, (len += 10));
        string[cnt++] = c;
    }

    string[cnt] = '\0';
    return string;
}