#include <iostream>
#include <string>
#include <vector>
#include <map>
using namespace std;

struct madtoken{
	string token;
	int type;
	//0 WORD
	//1 [
	//2 VALUEID
	//3 :
	//4 PROMPT
	//5 ]
	//6 SPACE
};

typedef struct madtoken madtoken;

void tokenize(string madlib); 
/* Grammar:
 	madlib: libword+
 	libword:  word
		| "["
		  valueid
 		  ("]"
		   |
		   ":"
		   prompt)

	prompt [^\]]+
	word [^\[ ]+
	valueid: [^\]:]+ */


vector<madtoken> toks;

int main()
{
	
	string madlib; 
	madlib += "[1:a proper noun] woke up. [1] didn't want to [2:a verb] today. "; 
	madlib += "It's [1]'s job to [2], which makes [1] [meh:a feeling]. ";
	madlib += "[1] wants to work somewhere [3:an adjective] like [4:a company]."; 
	madlib += " [1] plans to do this by conquering [5:a place] with [3] [animal:an animal(plural)].";
	madlib += " Then, everyone in [5] will be [meh] just like [1], and live [ly:an adverb] every after.";

	cout << "Not sane libs!" << endl << endl;
	map<string, string> inputs;
	tokenize(madlib);
	string story;
	for(int i=0; i<toks.size(); i++)
	{
		switch(toks[i].type)
		{
			case 0:
			story+=toks[i].token;
			break;
			case 1:
			if(toks[i+2].type != 3)		//If not prompting
			{
				story+=inputs[toks[i+1].token];
				i+=2;
			}
			else
			{
				cout << "Enter " << toks[i+3].token <<": ";
				cin >> inputs[toks[i+1].token];
				story+=inputs[toks[i+1].token];
				i+=4;
			}
			break;
			case 6:
				story += " ";	
		}
	}
	cout << endl << endl << story << endl;
}

void tokenize(string madlib)
{
	madlib+=" ";
	madtoken tok;
	int pos = 0;
	int state = 0; 
	string token="";
		// 0 - madlib
		// 1 - word
		// 2 - valueid
		// 3 - prompt
	while(pos < madlib.length())
	{
		switch(state)
		{
			case 0:
				
				if(madlib[pos]=='[')
				{
					pos++;    
					tok.token="["; tok.type=1;
					toks.push_back(tok);			
					token="";
					state=2;  //Begin parsing a valueid
				} else
				if(madlib[pos]==']')
				{
					cerr << "Unexpected ']'" << endl;
					return;
				}
				else if(madlib[pos]!=' ')
				{
					state=1; //Begin parsing a word
					token="";
				}
				else
				{
					pos++;
					tok.type=6; tok.token=" ";
					toks.push_back(tok);
				}
				break;
			case 1: //word
				if(madlib[pos]=='[' || madlib[pos] == ' ')
				{
					tok.token=token; tok.type=0;
					toks.push_back(tok);
					token="";
					state=0;
				}
				else {
				token += madlib[pos];
				pos++; } 
			break;
			case 2: //valueid 
				if(madlib[pos] != ']' && madlib[pos] != ':')
				{
					token+=madlib[pos];
					pos++;
				}
				else
				if(madlib[pos] == ']')
				{
					pos++;
					tok.token=token; tok.type=2;
					toks.push_back(tok);
					tok.token="]"; tok.type=5; // ']'
					toks.push_back(tok);
					token="]";
					state=0;
				} 
				else
				if(madlib[pos] == ':')
				{
					pos++;
					tok.token=token; tok.type=2;
					toks.push_back(tok);
					tok.token=":"; tok.type=3; // ':'
					toks.push_back(tok);
					token="";
					state=3; // start parsing prompt;
				}
				else
				{
					cerr << "Expected ']' or ':', found '" << madlib[pos] << "'" << endl;
					return;
				}
			break;
			case 3: //prompt (string w/ spaces)
				if(madlib[pos]!=']')
				{
					token+=madlib[pos];
					pos++;
				}
				else
				{
					pos++;
					tok.token=token; tok.type=4;
					toks.push_back(tok);
					tok.token="]"; tok.type=5; // ']'
					toks.push_back(tok);
					state=0;
				}
		}
	}	
}