/* Tanel Toova
 * 6-4
 *
 *
 */

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

#define END "LOPP"

FILE *inputfile;
FILE *outputfile;
struct node *first_node=NULL;
char input[256];
int i;

struct node{
    struct node *vasak;
    struct node *parem;
    char *word;
    int kordi;
};

//allocates memory for node
struct node *memalloc(void){
	return (struct node *)malloc(sizeof(struct node));
}

//adds node to the binary tree or increases the counter the if word is already there.
//if new word should be  before the last one in alphabetical order, it is added to the left else to the right
struct node *add_node(struct node *pointer, char *w)
{
	if(!pointer){
		pointer=memalloc();
		pointer->word=strdup(w);
		pointer->kordi=1;
		pointer->parem=NULL;
		pointer->vasak=NULL;
	}else{
		if(strcasecmp(pointer->word,w)==0){
			pointer->kordi++;
		}
		if(strcasecmp(pointer->word,w)>0){
			pointer->vasak=add_node(pointer->vasak,w);
		}
		if(strcasecmp(pointer->word,w)<0){
			pointer->parem=add_node(pointer->parem,w);
		}
	}
	return pointer;
}

//prints the binary tree into outputfile (which can be stdout) in alphabetical order
int print(struct node *pointer)
{	
	if(pointer->vasak!=NULL){print(pointer->vasak);}
	fprintf(outputfile,"sõna %s esines %i korda\n",pointer->word,pointer->kordi);
	if(pointer->parem!=NULL){print(pointer->parem);}
}

//if no inputfile is spetsified data will be read from keyboard until "LOPP" is given
int rkeyb(){
	fprintf(stdout,"Insert data manually, to stop insert LOPP\n");
	while(1){
        	fprintf(stdout,">");
                scanf("%s",input);
                if(strcmp(END,input)==0){break;}
                first_node=add_node(first_node,input);
        }
	print(first_node);	
}

//if inputfile is spetsified data will be read from it until eof
int rfile(char *input){
	inputfile=fopen(input,"r");
                if(!inputfile){
                        fprintf(stderr,"Error opening file %s\n",input);
                        exit(1);
                }
                while(1){
                        if ((i = fscanf(inputfile, "%s", input))== EOF){break;}
                        first_node=add_node(first_node,input);
                }
                fclose(inputfile);
		print(first_node);
}

int main(int argc, char **argv)
{
	if(argc>4){
		fprintf(stderr,"Wrong amount of parameters spetisfied\n");
		exit(1);
	}
	//if 3 command line parameters are given
	if(argc==4){
		if(strcasecmp(argv[3],"-o")==0){
			fprintf(stderr,"Illegal use of parameters\n");
			exit(1);
		}
		if(strcasecmp(argv[1],"-o")==0){
			outputfile=fopen(argv[2],"w");
			if(!outputfile){
				fprintf(stderr,"Can not open output file\n");
				exit(2);
			}
			rfile(argv[3]);
		}
		if(strcasecmp(argv[2],"-o")==0){
			outputfile=fopen(argv[3],"w");
                        if(!outputfile){
                                fprintf(stderr,"Can not open output file\n");
                                exit(2);
                        }
			rfile(argv[1]);
		}
	}
	if(argc==3){
		if(strcasecmp(argv[2],"-o")==0){
                        fprintf(stderr,"Illegal use of parameters\n");
			exit(1);
                }
		if(strcasecmp(argv[1],"-o")!=0 && strcasecmp(argv[2],"-o")!=0){
			fprintf(stderr,"Illegal use of parameters\n");
		}
		if(strcasecmp(argv[1],"-o")==0){
			outputfile=fopen(argv[2],"w");
                        if(!outputfile){
                                fprintf(stderr,"Can not open output file\n");
                                exit(2);
                        }
			rkeyb();
		}
	}
	if(argc==2){
		if(strcasecmp(argv[1],"-o")==0){
                        fprintf(stderr,"Illegal use of parameters\n");
			exit(1);
                }
		outputfile=stdout;
                        if(!outputfile){
                                fprintf(stderr,"Can not open stdout\n");
                                exit(2);
                        }
		rfile(argv[1]);
	}
	if(argc==1){
		outputfile=stdout;
                        if(!outputfile){
                                fprintf(stderr,"Can not open stdout\n");
                                exit(2);
                        }
		rkeyb();
	}
	if(outputfile){fclose(outputfile);}
	return(0);
}