#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#define MAX 200

struct passenger{
	char *name;
	struct passenger *next;
};

struct flightRecord{
	int flightNo;
	int flightCapacity;
	int reservationCount;
	struct passenger *passengersOnFlight;
	struct passenger *reservesForFlight;
	int dailyNo;
};

flightRecord* initialise(struct flightRecord *flights){
	FILE *text;
	int noOfDailyFlights;
	text = (fopen("text.txt","r"));
	fscanf(text, "%d ", &noOfDailyFlights);
	printf("%d flights are in today.\n\n",noOfDailyFlights);
	flights =(flightRecord *)malloc(noOfDailyFlights*sizeof(struct flightRecord));
	printf("Flight Numbers    Flight Capacity\n");
	int i = 0;
	while (!feof(text)){
		fscanf(text,"%d %d ",&(flights+i)->flightNo,&(flights+i)->flightCapacity);
		flights[i].dailyNo = noOfDailyFlights;
		flights[i].reservationCount = 0;
		printf("      %3d             %d\n",flights[i].flightNo,flights[i].flightCapacity);
		i++;
	}
	return flights;
}

void status(struct flightRecord *flights){
	int i = 0;
	struct flightRecord *temp= flights;

	for (i = 0;i < flights->dailyNo ; i++){

			printf("Flight number is: %d \n",temp[i].flightNo);
			printf("Flight capacity is: %d \n",temp[i].flightCapacity);
			printf("The people on flight are:\n");
			while(temp[i].passengersOnFlight){
				printf("%s\n",temp[i].passengersOnFlight->name);
				if(temp[i].passengersOnFlight->next)
					temp[i].passengersOnFlight = flights[i].passengersOnFlight->next;

			}
			while(temp[i].reservesForFlight){
				printf("%s\n",temp[i].reservesForFlight->name);
				if(temp[i].reservesForFlight->next)
					temp[i].reservesForFlight = temp[i].reservesForFlight->next;
			}
	}
}

flightRecord* reserve(char name[],int flightNo,struct flightRecord *flights){
	struct flightRecord *temp = flights;
	int i = 0,flag = 0;

	for(i;i < flights->dailyNo;i++){
		if(flightNo == temp[i].flightNo){
			flag++;

		}
	}

	if(flag == 0){
		printf("Flight is not found.");
	}

	else{

		for(i = 0;i < flights->dailyNo;i++){

			if(flightNo == temp[i].flightNo){

	            if(temp[i].reservationCount < temp[i].flightCapacity){
	                while(temp[i].passengersOnFlight != NULL){
	                    temp[i].passengersOnFlight= temp[i].passengersOnFlight->next;
	                }
	                (temp+i)->passengersOnFlight = (struct passenger*)malloc(sizeof(struct passenger));
	                strcpy(temp[i].passengersOnFlight->name,name);
	                temp[i].passengersOnFlight->next = NULL;
	                temp[i].reservationCount++;
	            }
	            else if(temp[i].reservationCount > temp[i].flightCapacity){
	            	while(temp[i].reservesForFlight != NULL){
	            		temp[i].reservesForFlight = temp[i].reservesForFlight->next;
					}
					(temp+i)->reservesForFlight = (struct passenger*)malloc(sizeof(struct passenger));
					strcpy(temp[i].reservesForFlight->name,name);
					temp[i].reservesForFlight->next = NULL;
				}



				printf("%d\n",temp[i].reservationCount);
	        }
	    }
	}
	for(i = 0;temp[i].passengersOnFlight->next;i++){
		printf("%s ",temp[i].passengersOnFlight->name);
		temp[i].passengersOnFlight = temp[i].passengersOnFlight->next;
	}
	return flights;
}

flightRecord* cancel(char name[],int flightNumber,struct flightRecord *flights){
		struct flightRecord *temp = flights;
	int i = 0,flag = 0;
	for(i;i < flights->dailyNo;i++){
		if(flightNumber == temp[i].flightNo){
			flag++;
		}
	}
	if(flag == 0){
		printf("Flight is not found.\n");
	}
	else{
		for(i = 0;i < temp[i].reservationCount;i++){
			if(strcmp(temp[i].passengersOnFlight->name,name) == 0){
				temp[i].passengersOnFlight = temp[i].passengersOnFlight->next;
				temp[i].reservationCount--;
			}
			else if(strcmp(temp[i].passengersOnFlight->next->name,name)== 0){
				temp[i].passengersOnFlight->next = temp[i].passengersOnFlight->next->next;
				temp[i].reservationCount--;
			}
		}
		while(temp[i].reservesForFlight->next){
			if(strcmp(temp[i].reservesForFlight->name,name)==0){
				temp[i].reservesForFlight = temp[i].reservesForFlight->next;
			}
			else if(strcmp(temp[i].reservesForFlight->next->name,name)==0){
				temp[i].reservesForFlight->next = temp[i].reservesForFlight->next->next;
			}
		}
	}
}
void inquire(struct flightRecord *flights){
	int i;
	struct flightRecord *temp = flights;
	for(i = 0; i < flights->dailyNo ; i++){
		printf("The flight number is %d.\n",temp[i].flightNo);
		printf("People on the flights are:\n");
	   while(temp[i].passengersOnFlight->next){
			printf("%s\n",temp[i].passengersOnFlight->name);
			temp[i].passengersOnFlight = temp[i].passengersOnFlight->next;
		}
		printf("People are waiting for this flight:\n");
		while(temp[i].reservesForFlight->next){
			printf("%s\n",temp[i].reservesForFlight->name);
			temp[i].reservesForFlight = temp[i].reservesForFlight->next;
		}
		printf("\n");
	}
}
void processCommands(struct flightRecord *flights){
	printf("\n");
	char command[10];
	char name[100];
	char flightNo[10];
	int totalSpaces = 0;
	int space = 0;
	int i , j , k, l;
	while(strcmp(command,"EXIT")!= 0){
		 i = 0, j = 0 , k= 0 , l = 0;
		printf("Enter the command: <COMMAND> <NAME> <FLIGHT NO>: ");
		fflush(stdin);
		char input[200];
		fgets(input, MAX, stdin);
		while(input[i]){
			if(input[i] == ' ')
				totalSpaces++;
			i++;
		}
		i = 0;
		while(input[i] != '\n'){
			if(input[i] == ' '){
				space++;
			}
			if (space == totalSpaces){
					flightNo[l] = input[i];
					l++;
			}
			if(space == 0){
				command[j] = input[i];
				j++;
			}
			else if (space > 0){
				if(space < totalSpaces){
					name[k] = input[i];
					k++;
				}
			}
			i++;
		}
		command[j] = '\0';
		name[k] = '\0';
		flightNo[l] = '\0';
		int flightNumber = atoi(flightNo);
		if (strcmp(command,"STATUS") == 0){
				status(flights);
		}

		else if(strcmp(command,"RESERVE")== 0){
			flights = reserve(name,flightNumber,flights);
		}
		else if(strcmp(command,"CANCEL")== 0){
			flights = cancel(name,flightNumber,flights);
		}
		else if(strcmp(command,"INQUIRE")==0){
			inquire(flights);
		}
	}
	struct flightRecord *temp = flights;
	for(i = 0;i < temp[i].reservationCount;i++){
		printf("%s",temp[i].passengersOnFlight->name);
	}
	printf("Thank you for using reservation system.");
}

int main(){
	struct flightRecord *flights = initialise(flights);
	processCommands(flights);

	return 0;
}