#include "debug.h"

#include "helpers.hpp"

#include "string.h"

#include <string>

#include <map>

class Driver {

public:

	virtual bool CanProbe() = 0;

	virtual const char *Start(const char * const *parm) = 0;

	virtual void Stop() = 0;

	virtual ~Driver() { }

	enum Type {

		DT_BEGIN = 0,

		DT_SOUND = 0,

		DT_MUSIC,

		DT_VIDEO,

		DT_END,

	};

};

DECLARE_POSTFIX_INCREMENT(Driver::Type);

class DriverFactoryBase {

private:

	Driver::Type type;

	char *name;

	typedef std::map<std::string, DriverFactoryBase *> Drivers;

	static Drivers &GetDrivers()

	{

		static Drivers &s_drivers = *new Drivers();

		return s_drivers;

	}

	static Driver **GetActiveDriver(Driver::Type type)

	{

		static Driver *s_driver[3] = { NULL, NULL, NULL };

		return &s_driver[type];

	}

	static const char *GetDriverTypeName(Driver::Type type)

	{

		static const char *driver_type_name[] = { "sound", "music", "video" };

		return driver_type_name[type];

	}

protected:

	/**

	 * Register a driver internally, based on its name.

	 * @param name the name of the driver.

	 * @note an assert() will be trigger if 2 driver with the same name try to register.

	 */

	void RegisterDriver(const char *name, Driver::Type type)

	{

		/* Don't register nameless Drivers */

		if (name == NULL) return;

		this->name = strdup(name);

		this->type = type;

		/* Prefix the name with driver type to make it unique */

		char buf[32];

		strecpy(buf, GetDriverTypeName(type), lastof(buf));

		strecpy(buf + 5, name, lastof(buf));

		std::pair<Drivers::iterator, bool> P = GetDrivers().insert(Drivers::value_type(buf, this));

		assert(P.second);

	}

public:

	DriverFactoryBase() :

		name(NULL)

	{}

	virtual ~DriverFactoryBase() { if (this->name != NULL) GetDrivers().erase(this->name); free(this->name); }

	/**

	 * Find the requested driver and return its class.

	 * @param name the driver to select.

	 * @post Sets the driver so GetCurrentDriver() returns it too.

	 */

	static Driver *SelectDriver(const char *name, Driver::Type type)

	{

		if (GetDrivers().size() == 0) return NULL;

		if (*name == '\0') {

			/* Probe for this driver */

			Drivers::iterator it = GetDrivers().begin();

			for (; it != GetDrivers().end(); ++it) {

				DriverFactoryBase *d = (*it).second;

				/* Check driver type */

				if (d->type != type) continue;

				Driver *newd = d->CreateInstance();

				if (!newd->CanProbe()) {

					DEBUG(driver, 1, "Skipping probe of driver '%s'", d->name);

				} else {

					const char *err = newd->Start(NULL);

					if (err == NULL) {

						DEBUG(driver, 1, "Successfully probed %s driver '%s'", GetDriverTypeName(type), d->name);

						delete *GetActiveDriver(type);

						*GetActiveDriver(type) = newd;

						return newd;

					}

					DEBUG(driver, 1, "Probing %s driver '%s' failed with error: %s", GetDriverTypeName(type), d->name, err);

				}

				delete newd;

			}

			error("Couldn't find any suitable %s driver", GetDriverTypeName(type));

		} else {

			char *parm;

			char buffer[256];

			const char *parms[32];

			/* Extract the driver name and put parameter list in parm */

			strecpy(buffer, name, lastof(buffer));

			parm = strchr(buffer, ':');

			parms[0] = NULL;

			if (parm != NULL) {

				uint np = 0;

				/* Tokenize the parm. */

				do {

					*parm++ = '\0';

					if (np < lengthof(parms) - 1)

						parms[np++] = parm;

					while (*parm != '\0' && *parm != ',')

						parm++;

				} while (*parm == ',');

				parms[np] = NULL;

			}

			/* Find this driver */

			Drivers::iterator it = GetDrivers().begin();

			for (; it != GetDrivers().end(); ++it) {

				DriverFactoryBase *d = (*it).second;

				/* Check driver type */

				if (d->type != type) continue;

				/* Check driver name */

				if (strcasecmp(buffer, d->name) != 0) continue;

				/* Found our driver, let's try it */

				Driver *newd = d->CreateInstance();

				const char *err = newd->Start(parms);

				if (err != NULL) {

					delete newd;

					error("Unable to load driver '%s'. The error was: %s", d->name, err);

				}

				DEBUG(driver, 1, "Successfully loaded %s driver '%s'", GetDriverTypeName(type), d->name);

				delete *GetActiveDriver(type);

				*GetActiveDriver(type) = newd;

				return newd;

			}

			error("No such %s driver: %s\n", GetDriverTypeName(type), buffer);

		}

	}

	/**

	 * Build a human readable list of available drivers, grouped by type.

	 */

	static char *GetDriversInfo(char *p, const char *last)

	{

		for (Driver::Type type = Driver::DT_BEGIN; type != Driver::DT_END; type++) {

			p += snprintf(p, last - p, "List of %s drivers:\n", GetDriverTypeName(type));

			Drivers::iterator it = GetDrivers().begin();

			for (; it != GetDrivers().end(); it++) {

				DriverFactoryBase *d = (*it).second;

				if (d->type == type) p += snprintf(p, last - p, "%18s: %s\n", d->name, d->GetDescription());

			}

			p += snprintf(p, last - p, "\n");

		}

		return p;

	}

	/**

	 * Get a nice description of the driver-class.

	 */

	virtual const char *GetDescription() = 0;

	/**

	 * Create an instance of this driver-class.

	 */

	virtual Driver *CreateInstance() = 0;

};