#include <iostream>
#include <string>
#include <cassert>
#include "multilog.h"


static int uniqid() {
	static int i = 0;
	return i++;
}


MultiLog::Item::Item()
		: id{uniqid()} {}

MultiLog::MultiLog(bool fancy)
		: fancy{fancy} {}

int MultiLog::add(const string_view prefix) {
	lock_guard guard(mut);

	assert(prefix.find('\n') == string::npos);

	items.emplace_back();
	items.back().line = prefix;
	if (fancy) {
		cout << prefix << endl;
	} else {
		cout << "[" << items.back().id << "] " << prefix << endl;
	}
	return items.back().id;
}

void MultiLog::append(int id, const string_view text) {
	lock_guard guard(mut);

	assert(text.find('\n') == string::npos);

	size_t idx = findId(id);
	items[idx].line += text;
	if (fancy) {
		redrawLine(idx);
	} else {
		cout << "[" << items[idx].id << "]... " << text << endl;
	}
}

void MultiLog::complete(int id) {
	lock_guard guard(mut);

	size_t idx = findId(id);
	items[idx].complete = true;
	size_t nextIdx;
	for (nextIdx = 0; nextIdx < items.size(); nextIdx++) {
		if (!items[nextIdx].complete) break;
	}
	if (nextIdx > 0) items.erase(items.begin(), items.begin() + (nextIdx - 1));
}

size_t MultiLog::findId(int id) {
	for (int i = 0; i < (int)items.size(); i++) {
		if (items[i].id == id) return i;
	}
	assert(false);
}

void MultiLog::redrawLine(size_t idx) {
	size_t offset = items.size() - idx;
	cout << "\r\x1B[" << offset << "A\x1B[K" << items[idx].line << "\r\x1B[" << offset << "B" << flush;
}