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

#include <fstream>
#include <iostream>

#include <systemd/sd-journal.h>
#include "re2/re2.h"

using namespace re2;
using namespace std;

// ideas: sort by usage
// configurable regex engine: http://sljit.sourceforge.net/regex_perf.html

void save_cursor(sd_journal* j, const char* filename) {
	char* cursor;
	//sd_journal_seek_tail(j);
	int r = sd_journal_get_cursor(j, &cursor);

	if (r >= 0) {
		cout << cursor << endl;
		FILE* f = fopen(filename, "wb");

		if (f) {
			fwrite(cursor, sizeof(char), strlen(cursor), f);
			free(cursor);
		}

		fclose(f);
	} else {
		cerr << "Failed to get cursor: " << strerror(-r) << endl;
	}

}

void seek_cursor(sd_journal* j, const char* filename) {
	FILE* f = fopen(filename, "rb");

	if (f) {
		fseek(f, 0, SEEK_END);
		long int s = ftell(f);

		if (s > 0) {
			fseek(f, 0, SEEK_SET);
			char* c = (char*)malloc(s);

			size_t r = fread(c, s, 1, f);
			if (r == 1) {
				cout << c << endl;
				sd_journal_seek_cursor(j, c);
			} else {
				cerr << "only " << r << endl;
			}

			free(c);
		} else {
			cerr << "empty file" << endl;
		}

		fclose(f);
	} else {
		fprintf(stderr, "Failed to open load cursor\n");
	}
}

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

	// read rules
	ifstream in("test.rules");
	string line;
	RE2 re1("^\\w\\{3\\} \\[ :0-9\\]\\{11\\} \\[._\\[:alnum:\\]-\\]\\+ (.*)\\[\\[0-9\\]+\\]: (.*)$");

	while (getline(in, line).good()) {
		//cout << line << endl;
	}



	int r;
	sd_journal* j;

	r = sd_journal_open(&j, SD_JOURNAL_LOCAL_ONLY);

	if (r < 0) {
		fprintf(stderr, "Failed to open journal: %s\n", strerror(-r));
		return 1;
	}

	seek_cursor(j, "last");
	// skip current
	sd_journal_next(j);

	RE2 re(".*pixmap$");

	if (!re.ok()) {
		printf("pattern error!\n");
		return 1;
	}


	while (sd_journal_next(j) > 0) {
		const char* d;
		size_t l;

		r = sd_journal_get_data(j, "MESSAGE", (const void**)&d, &l);

		if (r < 0) {
			fprintf(stderr, "Failed to read message field: %s\n", strerror(-r));
			continue;

		}

		re2::StringPiece input(d, l);

		//if (RE2::FullMatch(input, re)) {
			// printf("match: %d %d @%d\n", result.data() - subject, result.size(), input.data() - subject);
			printf("%.*s\n", (int) l, d);
		//}

		//
	}

	//sd_journal_previous(j);
	save_cursor(j, "last");

	sd_journal_close(j);

	return 0;
}