// Copyright (c) 2011 Bryan Schumaker.
#include <format.h>
#include <print.h>

#include <map>
#include <set>
#include <sstream>
using namespace std;

static map<string, set<string> > format_cache;
static map<string, set<string> > substr_cache;
static map<string, string> lc_cache;
static unsigned int format_hits = 0;
static unsigned int substr_hits = 0;
static unsigned int lc_hits = 0;

static const unsigned int TM_SECOND = 1;
static const unsigned int TM_MINUTE = 60;
static const unsigned int TM_HOUR   = TM_MINUTE * 60;
static const unsigned int TM_DAY    = TM_HOUR * 24;

void do_format(const string &text,
	      map<string, set<string> >::iterator &words,
	      map<string, string>::iterator &lc)
{
	string word;
	string lc_string;
	set<string> word_set;
	pair< map<string, set<string> >::iterator, bool > ret1;
	pair< map<string, string>::iterator, bool > ret2;
	char c, diff = 'a' - 'A';

	for (unsigned int i = 0; i < text.size(); i++) {
		c = text[i];
		// Character already lower case
		if ( (c >= 'a') && (c <= 'z') )
			word += c;
		// Convert uppercase to lowercase
		else if ( (c >= 'A') && (c <= 'Z') )
			word += (c + diff);
		// Keep numbers
		else if ( (c >= '0') && (c <= '9') )
			word += c;
		else {
			// These characters indicate a new word
			switch (c) {
			case '-':
			case '\\':
			case '/':
			case ',':
			case ';':
			case '(':
			case ')':
			case '_':
			case '~':
			case '+':
			case '"':
			case ' ':
				if (word != "") {
					word_set.insert(word);
					if (lc_string == "")
						lc_string = word;
					else
						lc_string += " " + word;
				}
				word = "";
				break;
			default:
				break;
			};
		}
	}

	if (word != "") {
		word_set.insert(word);
		if (lc_string == "")
			lc_string = word;
		else
			lc_string += " " + word;
	}

	ret1 = format_cache.insert( pair<string, set<string> >(text, word_set) );
	ret2 = lc_cache.insert( pair<string, string>(text, lc_string) );
	words = ret1.first;
	lc = ret2.first;
}

void find_unique_words(const string &text,
		       map<string, set<string> >::iterator &words)
{
	map<string, string>::iterator lc;
	do_format(text, words, lc);
}

static set<string> *gen_substrs(const string &word)
{
	string key;
	set<string> substrs;
	pair< map<string, set<string> >::iterator, bool > ret;

	for (unsigned int i = 1; i <= word.size(); i++) {
		key = word.substr(0, i);
		substrs.insert(key);
	}

	ret = substr_cache.insert( pair<string, set<string> >(word, substrs));
	return &(ret.first->second);
}

static set<string> *find_substrs(const string &word)
{
	map<string, set<string> >::iterator it;
	it = substr_cache.find(word);
	if (it == substr_cache.end())
		return gen_substrs(word);
	else {
		substr_hits++;
		return &(it->second);
	}
}

void find_lowercase(const string &text,
		    map<string, string>::iterator &lc)
{
	map<string, set<string> >::iterator words;
	do_format(text, words, lc);
}

unsigned int add_to_stream(stringstream &stream, const unsigned int factor,
			   string field, unsigned int length, unsigned int total)
{
	unsigned int res = length / factor;
	if (res == 0)
		return 0;

	if (total != 0)
		stream << ", ";
	stream << res << " " << field;
	if (res > 1)
		stream << "s";

	return res * factor;;
}

namespace libsaria
{

	set<string> *format_text(const string &text)
	{
		map<string, set<string> >::iterator it;
		it = format_cache.find(text);

		/* Not found in cache... */
		if (it == format_cache.end())
			find_unique_words(text, it);
		else
			format_hits++;
		return &(it->second);
	}

	void format_substrs(const string &text, set<string> &res)
	{
		set<string> *words, *substrs;
		set<string>::iterator it;

		words = format_text(text);
		for (it = words->begin(); it != words->end(); it++) {
			substrs = find_substrs(*it);
			res.insert(substrs->begin(), substrs->end());
		}
	}

	string *lowercase(const string &text)
	{
		map<string, string>::iterator it;
		it = lc_cache.find(text);

		/* Not found in cache */
		if (it == lc_cache.end())
			find_lowercase(text, it);
		else
			lc_hits++;
		return &(it->second);
	}

	string length_string(unsigned int len)
	{
		unsigned int tot;
		stringstream stream;

		if (len == 0)
			return "";

		tot  = add_to_stream(stream, TM_DAY,    "day",    len,       0);
		tot += add_to_stream(stream, TM_HOUR,   "hour",   len - tot, tot);
		tot += add_to_stream(stream, TM_MINUTE, "minute", len - tot, tot);

		add_to_stream(stream, TM_SECOND, "second", len - tot, tot);
		return stream.str();
	}

	void print_format_stats()
	{
		println("Format cache hits: %u size: %u", format_hits, format_cache.size());
		println("Substring cache hits: %u size: %u", substr_hits, substr_cache.size());
		println("Lowercase cache hits: %u size: %u", lc_hits, lc_cache.size());
	}

} /* Namespace: libsaria */