//this is op4
//the author is liqinwei
//2007/12/1
#include <iostream>
#include <fstream>
#include <string>
#include <sstream>
#include <cstdlib>
#include <cctype>

#include "dictionary.h"

using namespace std;

static char letter[] = { //define the change letter
	'a','b','c','d','e','f','g','h','i','j','k','l','m','n'
		,'o','p','q','r','s','t','u','v','w','x','y','z'
};


void lower(string& s);
string strip_punct(const string& s);
void check_spelling(ifstream& in, Dictionary& dict);
string transpose_letter(string s,int i);//Transposing of adjacent letters 
string replace_letter(string s,int local,int k);//Replacement of each letter 
string insert_letter(string s,int local,int l);//Inserting any letter at any position in a word 


int main(int argc, char* argv[]) {

	// Output usage message if improper command line args were given.
	if (argc != 3) {
		cerr << "Usage: " << argv[0] << " wordlist_filename input_file\n";
		return EXIT_FAILURE;
	}

	ifstream inf(argv[2]);
	if (! inf) {
		cerr << "Could not open " << argv[2] << "\n";
		return EXIT_FAILURE;
	}

	// Read dictionary, but let user know what we are working on.
	cout << "Loading dictionary, this may take awhile...\n";

	Dictionary d(argv[1]);

	check_spelling(inf, d);

	inf.close();

	return EXIT_SUCCESS;
}

void check_spelling(ifstream& in, Dictionary& dict) {

	int line_number = 0;

	while (in) {

		line_number++;

		string line;
		getline(in, line);

  	    stringstream ss (stringstream::in | stringstream::out);
		ss << line;

		string word;
		while (ss >> word) {
			
			lower(word);
			word = strip_punct(word);
			if(!dict.search(word))
			{
				cout <<"line " <<line_number<<": '"<< word <<"' "<<endl;
				cout << "        suggestions:"<<endl;
				//Transposing of adjacent letters 
				for(int i= 0;i < word.size();i++)
				{
					if(dict.search(transpose_letter(word,i)))
						cout << "                "<<transpose_letter(word,i)<<endl;
				}
				//Removal of each letter 
				for(int j= 0;j < word.size();j++)
				{
					string s = word;
					if(dict.search(s.erase(j,1)))
						cout << "                "<<s<<endl;
					//if the contiguity letter is same,jump the location
					if(dict.search(s)&&word[j]==word[j+1]) j++;

				}
				//Replacement of each letter 
				for(int k= 0;k < word.size();k++)
				{
					for(int i = 0; i <sizeof(letter); i++)
					{
						if(dict.search(replace_letter(word,i,k)))
							cout << "                "<<replace_letter(word,i,k)<<endl;
					}
				}
				//Inserting any letter at any position in a word 
				for(int l= 0;l < word.size();l++)
				{

					for(int i = 0; i <sizeof(letter); i++)
					{

						if(dict.search(insert_letter(word,i,l)))
								cout << "                "<<insert_letter(word,i,l)<<endl;
						//if the contiguity letter is same,jump the location
						if(word[l]==letter[i]&&dict.search(insert_letter(word,i,l))) l++;

					}
				}
			}
		}
	}
}

void lower(string& s) {

    // Ensures that a word is lowercase
	for (int i = 0; i < s.length(); i++) {
		s[i] = tolower(s[i]);
	}
}

string strip_punct(const string& s) {

	// Remove any single trailing
	// punctuation character from a word.  
	if (ispunct(s[s.length() - 1]) ) {
		return s.substr (0, s.length() - 1);
	}
	else {
		return s;
	}
}

string transpose_letter(string s,int local){

	//Transposing of adjacent letters 
 	int j= local+1;
	char c = s[local]; s[local]=s[j]; s[j] = c;
	return s;
}

string replace_letter(string s,int local,int k){

	//Replacement of each letter 
	s[k] = letter[local];
	return s;
}

string insert_letter(string s,int local,int l){

	//Inserting any letter at any position in a word 
	s.insert(l,1,letter[local]);
	return s;
}