/*
dbRW

Copyright 2000-2017 Miranda ICQ/IM project,
all portions of this codebase are copyrighted to the people
listed in contributors.txt.

This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License
as published by the Free Software Foundation; either version 2
of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
*/

#include "stdafx.h"

PLUGININFOEX pluginInfo =
{
	sizeof(PLUGININFOEX),
	__PLUGIN_NAME,
	PLUGIN_MAKE_VERSION(__MAJOR_VERSION, __MINOR_VERSION, __RELEASE_NUM, __BUILD_NUM),
	__DESCRIPTION,
	__AUTHOR,
	__COPYRIGHT,
	__AUTHORWEB,
	UNICODE_AWARE,
	// {F3CA0E5E-249A-40f0-8D74-80A80EF0C83D}
	{0xf3ca0e5e, 0x249a, 0x40f0, {0x8d, 0x74, 0x80, 0xa8, 0xe, 0xf0, 0xc8, 0x3d}}
};

HINSTANCE g_hInst;

sqlite3 *g_sqlite;
char g_szDbPath[MAX_PATH];
HANDLE hSettingChangeEvent;
HANDLE hContactDeletedEvent;
HANDLE hContactAddedEvent;
HANDLE hEventFilterAddedEvent;
HANDLE hEventAddedEvent;
HANDLE hEventDeletedEvent;

enum {
	DBRW_TABLE_SETTINGS = 0,
	DBRW_TABLE_CONTACTS,
	DBRW_TABLE_EVENTS,
	DBRW_TABLE_CORE,
	DBRW_TABLE_COUNT
};

char *dbrw_tables[DBRW_TABLE_COUNT] = {
"create table dbrw_settings (id integer, module varchar(255), setting varchar(255), type integer, val any, primary key(id,module,setting));",
"create table dbrw_contacts (id integer primary key,createtime integer);",
"create table dbrw_events (id integer primary key,eventtime integer,flags integer,eventtype integer, blob any, blobsize integer, contactid integer,modulename varchar(255),inserttime integer);",
"create table dbrw_core (setting varchar(255) primary key not null, val any);"
};

char* utf8_encode(const char* src) {
	size_t len;
	char* result;
	wchar_t* tempBuf;

	if (src == NULL)
		return NULL;
	len = strlen(src);
	result = (char*)malloc(len * 3 + 1);
	if (result == NULL)
		return NULL;
	tempBuf = (wchar_t*)alloca((len + 1) * sizeof(wchar_t));
	MultiByteToWideChar(CP_ACP, 0, src, -1, tempBuf, (int)len);
	tempBuf[len] = 0;
	{
		wchar_t* s = tempBuf;
		BYTE* d = (BYTE*)result;

		while (*s) {
			int U = *s++;

			if (U < 0x80) {
				*d++ = (BYTE)U;
			}
			else if (U < 0x800) {
				*d++ = 0xC0 + ((U >> 6) & 0x3F);
				*d++ = 0x80 + (U & 0x003F);
			}
			else {
				*d++ = 0xE0 + (U >> 12);
				*d++ = 0x80 + ((U >> 6) & 0x3F);
				*d++ = 0x80 + (U & 0x3F);
			}
		}
		*d = 0;
	}
	return result;
}

static int dbrw_makeDatabase(char *profile, int *error) {
	sqlite3 *sql = NULL;
	int rc;
	char *szPath = utf8_encode(profile);

	rc = sqlite3_open(szPath, &sql);
	free(szPath);
	if (rc == SQLITE_OK) {
		int x;

		sqlite3_exec(sql, "PRAGMA page_size = 8192;", NULL, NULL, NULL);
		for (x = 0; x < DBRW_TABLE_COUNT; x++) {
			rc = sqlite3_exec(sql, dbrw_tables[x], NULL, NULL, NULL);
			if (rc != SQLITE_OK)
				break;
		}
		if (rc == SQLITE_OK) {
			sqlite3_exec(sql, "CREATE INDEX idx_settings1 ON dbrw_settings(id, module, setting);", NULL, NULL, NULL);
			sqlite3_exec(sql, "CREATE INDEX idx_settings2 ON dbrw_settings(id, module);", NULL, NULL, NULL);
			sqlite3_exec(sql, "CREATE INDEX idx_settings3 ON dbrw_settings(module);", NULL, NULL, NULL);
			sqlite3_exec(sql, "CREATE INDEX idx_events1 ON dbrw_events(contactid);", NULL, NULL, NULL);
			sqlite3_exec(sql, "CREATE INDEX idx_events2 ON dbrw_events(id,contactid);", NULL, NULL, NULL);
			sqlite3_exec(sql, "INSERT INTO dbrw_core VALUES(\"SchemaVersion\",\"" DBRW_SCHEMA_VERSION "\");", NULL, NULL, NULL);
		}
	}
	sqlite3_close(sql);
	rc = (rc == SQLITE_OK) ? 0 : 1;
	if (error != NULL) *error = rc;
	return rc;
}

static int dbrw_grokHeader(char *profile, int *error) {
	HANDLE hFile = CreateFileA(profile, GENERIC_READ, 0, NULL, OPEN_ALWAYS, 0, NULL);
	int rc = 1;
	int err = EGROKPRF_CANTREAD;

	if (hFile != INVALID_HANDLE_VALUE) {
		BOOL r;
		char buf[64];
		DWORD dwRead;

		ZeroMemory(buf, sizeof(buf));
		r = ReadFile(hFile, buf, sizeof(buf), &dwRead, NULL);
		CloseHandle(hFile);
		if (r && memcmp(buf, DBRW_HEADER_STR, strlen(DBRW_HEADER_STR)) == 0) {
			sqlite3 *sqlcheck = NULL;
			char *szPath = utf8_encode(profile);

			rc = sqlite3_open(szPath, &sqlcheck);
			free(szPath);
			if (rc == SQLITE_OK) {
				sqlite3_stmt *stmt;
				err = EGROKPRF_UNKHEADER;

				sqlite3_prepare_v2(sqlcheck, "select * from sqlite_master where type = 'table' and name = 'dbrw_core';", -1, &stmt, NULL);
				if (sqlite3_step(stmt) == SQLITE_ROW) {

					sqlite3_finalize(stmt);
					sqlite3_prepare_v2(sqlcheck, "select val from dbrw_core where setting = 'SchemaVersion';", -1, &stmt, NULL);
					if (sqlite3_step(stmt) == SQLITE_ROW) {
						int sVersion;

						sVersion = sqlite3_column_int(stmt, 0);
						if (sVersion == atoi(DBRW_SCHEMA_VERSION))
							rc = 0;
						else {
							// TODO: Return as valid and upgrade in 
							// dbrw_Load() if schema version is upgradable
						}
					}
				}
				sqlite3_finalize(stmt);
				sqlite3_close(sqlcheck);
			}
		}
		else err = r ? EGROKPRF_UNKHEADER : EGROKPRF_CANTREAD;
	}
	if (error != NULL)
		*error = err;
	return rc;
}

static int dbrw_Load(char *profile, void *link)
{
	{
		char *szLocalPath = mir_utf8encode(profile);
		mir_snprintf(g_szDbPath, sizeof(g_szDbPath), "%s", szLocalPath);
		mir_free(szLocalPath);
	}
	sql_init(); // intialize sqlite library routines
	if (sql_open(g_szDbPath, &g_sqlite) != SQLITE_OK)
		return 1;
#ifdef DBRW_LOGGING
	utils_log_init();
#endif
	log2("Loading SQLite Driver v%s (SQLite v%s)", DBRW_VER_STRING, SQLITE_VERSION);
	utils_vacuum_check();
	{
		sql_exec(g_sqlite, "BEGIN TRANSACTION;");
		sql_exec(g_sqlite, "PRAGMA locking_mode = EXCLUSIVE;");
		sql_exec(g_sqlite, "PRAGMA synchronous = NORMAL;");
		sql_exec(g_sqlite, "PRAGMA cache_size = 6000;");
		sql_exec(g_sqlite, "PRAGMA temp_store = MEMORY;");
		sql_exec(g_sqlite, "COMMIT;");
	}

	// Create Services
	/*CreateServiceFunction(MS_DB_SETSAFETYMODE, utils_setSafetyMode);
	CreateServiceFunction(MS_DB_CONTACT_GETSETTING, setting_getSetting);
	CreateServiceFunction(MS_DB_CONTACT_GETSETTING_STR, setting_getSettingStr);
	CreateServiceFunction(MS_DB_CONTACT_GETSETTINGSTATIC, setting_getSettingStatic);
	CreateServiceFunction(MS_DB_CONTACT_FREEVARIANT, setting_freeVariant);
	CreateServiceFunction(MS_DB_CONTACT_WRITESETTING, setting_writeSetting);
	CreateServiceFunction(MS_DB_CONTACT_DELETESETTING, setting_deleteSetting);
	CreateServiceFunction(MS_DB_CONTACT_ENUMSETTINGS, setting_enumSettings);
	CreateServiceFunction(MS_DB_SETSETTINGRESIDENT, settings_setResident);
	CreateServiceFunction(MS_DB_CONTACT_GETCOUNT, contacts_getCount);
	CreateServiceFunction(MS_DB_CONTACT_FINDFIRST, contacts_findFirst);
	CreateServiceFunction(MS_DB_CONTACT_FINDNEXT, contacts_findNext);
	CreateServiceFunction(MS_DB_CONTACT_DELETE, contacts_delete);
	CreateServiceFunction(MS_DB_CONTACT_ADD, contacts_add);
	CreateServiceFunction(MS_DB_CONTACT_IS, contacts_isContact);
	CreateServiceFunction(MS_DB_EVENT_GETCOUNT, events_getCount);
	CreateServiceFunction(MS_DB_EVENT_ADD, events_add);
	CreateServiceFunction(MS_DB_EVENT_DELETE, events_delete);
	CreateServiceFunction(MS_DB_EVENT_GETBLOBSIZE, events_getBlobSize);
	CreateServiceFunction(MS_DB_EVENT_GET, events_get);
	CreateServiceFunction(MS_DB_EVENT_MARKREAD, events_markRead);
	CreateServiceFunction(MS_DB_EVENT_GETCONTACT, events_getContact);
	CreateServiceFunction(MS_DB_EVENT_FINDFIRST, events_findFirst);
	CreateServiceFunction(MS_DB_EVENT_FINDFIRSTUNREAD, events_findFirstUnread);
	CreateServiceFunction(MS_DB_EVENT_FINDLAST, events_findLast);
	CreateServiceFunction(MS_DB_EVENT_FINDNEXT, events_findNext);
	CreateServiceFunction(MS_DB_EVENT_FINDPREV, events_findPrev);
	CreateServiceFunction(MS_DB_CRYPT_ENCODESTRING, utils_encodeString);
	CreateServiceFunction(MS_DB_CRYPT_DECODESTRING, utils_decodeString);
	CreateServiceFunction(MS_DB_MODULES_ENUM, setting_modulesEnum);*/

	// Events Hooks
	hSettingChangeEvent = CreateHookableEvent(ME_DB_CONTACT_SETTINGCHANGED);
	hContactDeletedEvent = CreateHookableEvent(ME_DB_CONTACT_DELETED);
	hContactAddedEvent = CreateHookableEvent(ME_DB_CONTACT_ADDED);
	hEventFilterAddedEvent = CreateHookableEvent(ME_DB_EVENT_FILTER_ADD);
	hEventAddedEvent = CreateHookableEvent(ME_DB_EVENT_ADDED);
	hEventDeletedEvent = CreateHookableEvent(ME_DB_EVENT_DELETED);

	// Initialize modules
	contacts_init();
	settings_init();
	events_init();

	// Prepare SQL statements
	sql_prepare_statements();

	return 0;
}

static int dbrw_Unload(int wasLoaded) {
	if (!wasLoaded)
		return 0;
	events_destroy();
	settings_destroy();
	contacts_destroy();
	sql_close(g_sqlite);
	sql_destroy();
	log0("SQLite Driver unloaded sucessfully");
#ifdef DBRW_LOGGING
	utils_log_destroy();
#endif
	return 0;
}

static DATABASELINK dblink =
{
	sizeof(DATABASELINK),
	"dbrw",
	L"dbx SQLite driver",
	dbrw_makeDatabase,
	dbrw_grokHeader,
	dbrw_Load,
	dbrw_Unload
};

/////////////////////////////////////////////////////////////////////////////////////////

BOOL WINAPI DllMain(HINSTANCE hInstDLL, DWORD, LPVOID)
{
	g_hInst = hInstDLL;
	return TRUE;
}

extern "C" __declspec(dllexport) PLUGININFOEX* MirandaPluginInfoEx(DWORD mirandaVersion)
{
	return &pluginInfo;
}

extern "C" __declspec(dllexport) const MUUID MirandaInterfaces[] = { MIID_DATABASE, MIID_LAST };

extern "C" __declspec(dllexport) int Load(void)
{
	RegisterDatabasePlugin(&dblink);
	return 1;
}

extern "C" __declspec(dllexport) int Unload(void)
{
	return 0;
}