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#include "storage.h"
#include "config.h"
#include <chrono>
#include <iostream>
#include <random>
#include <SQLiteCpp/SQLiteCpp.h>
using namespace std::string_literals;
Storage::Storage(const Config& config):
m_db(config.getDataPath() + "/whiteboard.db3", SQLite::OPEN_READWRITE | SQLite::OPEN_CREATE),
m_maxage(config.getMaxage()),
m_stmt_create(m_db),
m_stmt_getNumberOfDocuments(m_db),
m_stmt_cleanup(m_db),
m_stmt_exists(m_db),
m_stmt_getDocument(m_db),
m_stmt_getRevision(m_db),
m_stmt_getCursorPos(m_db),
m_stmt_getRow(m_db),
m_stmt_setDocument(m_db),
m_stmt_setDocument_new(m_db),
m_stmt_setRevision(m_db),
m_stmt_setCursorPos(m_db),
m_stmt_setRow(m_db)
{
m_stmt_create.init("CREATE TABLE IF NOT EXISTS documents (id VARCHAR(16) PRIMARY KEY, value BLOB, rev INTEGER, cursorpos INTEGER, timestamp BIGINT)");
m_stmt_create.execute();
}
Storage::~Storage()
{
}
uint64_t Storage::getNumberOfDocuments()
{
m_stmt_getNumberOfDocuments.init("SELECT COUNT(*) FROM documents");
if (!m_stmt_getNumberOfDocuments.execute())
throw std::runtime_error("Count not possible");
return m_stmt_getNumberOfDocuments.getColumn<int64_t>(0);
}
namespace {
uint64_t unixepoch()
{
const auto p1 = std::chrono::system_clock::now();
return std::chrono::duration_cast<std::chrono::seconds>(p1.time_since_epoch()).count();
}
} // namespace
void Storage::cleanup()
{
if (m_maxage == 0)
return;
m_stmt_cleanup.init("DELETE FROM documents WHERE timestamp + ? < ?");
m_stmt_cleanup.bind(1, static_cast<int64_t>(m_maxage));
m_stmt_cleanup.bind(2, static_cast<int64_t>(unixepoch()));
m_stmt_cleanup.execute();
}
bool Storage::exists(const std::string& id)
{
m_stmt_exists.init("SELECT id FROM documents WHERE id = ?");
m_stmt_exists.bind(1, id);
return m_stmt_exists.execute();
}
std::string Storage::getDocument(const std::string& id)
{
m_stmt_getDocument.init("SELECT value FROM documents WHERE id = ?");
m_stmt_getDocument.bind(1, id);
if (!m_stmt_getDocument.execute())
throw std::runtime_error("id "s + id + " not found"s);
return m_stmt_getDocument.getColumn<std::string>(0);
}
int Storage::getRevision(const std::string& id)
{
m_stmt_getRevision.init("SELECT rev FROM documents WHERE id = ?");
m_stmt_getRevision.bind(1, id);
if (!m_stmt_getRevision.execute())
throw std::runtime_error("id "s + id + " not found"s);
return m_stmt_getRevision.getColumn<int>(0);
}
int Storage::getCursorPos(const std::string& id)
{
m_stmt_getCursorPos.init("SELECT cursorpos FROM documents WHERE id = ?");
m_stmt_getCursorPos.bind(1, id);
if (!m_stmt_getCursorPos.execute())
throw std::runtime_error("id "s + id + " not found"s);
return m_stmt_getCursorPos.getColumn<int>(0);
}
std::tuple<std::string, int, int> Storage::getRow(const std::string& id)
{
m_stmt_getRow.init("SELECT value, rev, cursorpos FROM documents WHERE id = ?");
m_stmt_getRow.bind(1, id);
if (!m_stmt_getRow.execute())
throw std::runtime_error("id "s + id + " not found"s);
return {m_stmt_getRow.getColumn<std::string>(0), m_stmt_getRow.getColumn<int>(1), m_stmt_getRow.getColumn<int>(2)};
}
void Storage::setDocument(const std::string& id, const std::string& document)
{
m_stmt_setDocument.init("UPDATE documents SET value = ?, timestamp = ?, rev = rev + 1 WHERE id = ?");
m_stmt_setDocument.bind(1, document);
m_stmt_setDocument.bind(2, static_cast<int64_t>(unixepoch()));
m_stmt_setDocument.bind(3, id);
if (!m_stmt_setDocument.execute()) {
m_stmt_setDocument_new.init("INSERT INTO documents (id, value, rev, cursorpos, timestamp) values (?, ?, ?, ?, ?)");
m_stmt_setDocument_new.bind(1, id);
m_stmt_setDocument_new.bind(2, document);
m_stmt_setDocument_new.bind(3, 0);
m_stmt_setDocument_new.bind(4, 0);
m_stmt_setDocument_new.bind(5, static_cast<int64_t>(unixepoch()));
m_stmt_setDocument_new.execute();
}
}
void Storage::setRevision(const std::string& id, int rev)
{
m_stmt_setRevision.init("UPDATE documents SET rev = ? WHERE id = ?");
m_stmt_setRevision.bind(1, rev);
m_stmt_setRevision.bind(2, id);
if (!m_stmt_setRevision.execute())
throw std::runtime_error("Unable to insert row with id "s + id);
}
void Storage::setCursorPos(const std::string& id, int cursorPos)
{
m_stmt_setCursorPos.init("UPDATE documents SET cursorpos = ? WHERE id = ?");
m_stmt_setCursorPos.bind(1, cursorPos);
m_stmt_setCursorPos.bind(2, id);
if (!m_stmt_setCursorPos.execute())
throw std::runtime_error("Unable to insert row with id "s + id);
}
void Storage::setRow(const std::string& id, const std::string& document, int rev, int cursorPos)
{
m_stmt_setRow.init("INSERT OR REPLACE INTO documents (id, value, rev, cursorpos, timestamp) values (?, ?, ?, ?, ?)");
m_stmt_setRow.bind(1, id);
m_stmt_setRow.bind(2, document);
m_stmt_setRow.bind(3, rev);
m_stmt_setRow.bind(4, cursorPos);
m_stmt_setRow.bind(5, static_cast<int64_t>(unixepoch()));
if (!m_stmt_setRow.execute())
throw std::runtime_error("Unable to insert row with id "s + id);
}
uint32_t Storage::checksum32(const std::string& s)
{
uint32_t result{0};
for (unsigned int i = 0; i < s.size(); i++) {
result = ((result >> 1) | ((result & 1) << 31)) ^ (s[i] & 0xFF);
}
return result & 0x7FFFFFFF;
}
std::string Storage::generate_id()
{
static std::random_device r;
static std::default_random_engine e1(r());
static std::uniform_int_distribution<int> uniform_dist(0, 35);
// limit tries
for (int j = 0; j < 100000; j++) {
std::string result;
for (int i = 0; i < 6; i++) {
char c{static_cast<char>('0' + uniform_dist(e1))};
if (c > '9')
c = c - '9' - 1 + 'a';
result.push_back(c);
}
if (!exists(result))
return result;
}
return "endofcodes";
}
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