#ifndef ZENTIFIC_TYPES_H
#define ZENTIFIC_TYPES_H

/* default priorities for each job type */
#define JOBPRIORITY_IMMEDIATE 10
#define JOBPRIORITY_HIGH      5
#define JOBPRIORITY_DEFAULT   3
#define JOBPRIORITY_LOW       1

/* relative execution speed estimations */
#define JOBSPEED_SLOW         10
#define JOBSPEED_DEFAULT      5
#define JOBSPEED_FAST         1

/* status of the execution of a job */
#define JOBSTATUS_INSERTED		0
#define JOBSTATUS_FETCHED		1
#define JOBSTATUS_ENQUEUED		2
#define JOBSTATUS_EXECUTING		3
#define JOBSTATUS_COMPLETED		4
#define JOBSTATUS_CANCELLED		5

#include "zentific/adts.h"

/**
 * Describes a job action to perform.
 * 
 * The priority can be provided in the database or left NULL. If it is NULL, then it is assumed to
 * be JOBPRIORITY_DEFAULT. The only exceptions to this are the "cancel" job, which is always a
 * priority JOBPRIORITY_IMMEDIATE, and a "domain_update" job, which is also a JOBPRIORITY_IMMEDIATE.
 * These two are executed right away because they affect other jobs that may have been ahead of them
 * in the execution queue. 
 */
typedef struct t_zJob {
	/* describes the job as it is listed in the database */
	int id;     /* a unique identifier for this job (only needs to be unique to the source) */
	struct t_zJobSource *source;	/* identifies which source the job came from. Used for write-backs */
	int runtype;   /* 0 = normal job, 1 = scheduled one-time job, 2 = scheduled, repeating job */
	int priority;	/* one of the JOBPRIORITY defines from above */
	char domU[38];	/* UUID of target DomU with dashes */
	char dom0[38];	/* UUID of target Dom0 with dashes */
	char host[16];	/* IP address with periods */
	char extra[256];	/* other job-related data */

	/* describes which job type will handle the execution */
	char jobtype_class[32];
	char jobtype_name[256];
	
	/* describes the job as it is executing */
	unsigned int pid;        	/* PID of the job while it is executing */
	unsigned int time_started;	/* UNIX timestamp */
	unsigned int status;			/* Job Status */
	int return_value;	/* value returned from the execution */

	void* jobtype;	/* job type structure to use in executing the job */
	
	/** WARNING: These two are deprecated and will be removed in future versions. Write new
	 * jobtypes off of the "addon" jobtype pattern (see jobtypes/addon/README.txt)
	 */
	char *jobtype_string;	/* string for the action to execute in shell (if needed). Unparsed. */
	int jobtype_speed;		/* options are JOBSPEED_SLOW, JOBSPEED_DEFAULT, or JOBSPEED_FAST */

	/* used to lock the job when we need to modify properties */
	sem_t mutex;
} zJob;

/**
 * Defines all of the necessary information for a job source
 */
typedef struct t_zJobSource {
	/* reference to the library descriptor to unload in the end */
	void *library;
	
	/* configuration data provided by init call */
	void *config;
	
	/* initialize function that is called during preparation */
	void *(*init)(void);
	
	/* fetch function to call each time there is a new job */
	int (*fetch)(void *, struct t_zList*, int, struct t_zJobSource*);
	
	/* update function to call when a job has changed */
	int (*update)(void *, struct t_zJob*);
	
	/* uninit function call when exiting */
	int (*uninit)(void *);
} zJobSource;

/**
 * Represents a physical machine
 */
typedef struct t_zDom0 {
	int id;
	char *uuid;
	char *hostname;
	//char uuid[37];
	//char hostname[256];

	// flags to keep track of jobs
	int busy;
	struct z_job *current_job;

	// list of VMs running on this domain
	struct zList *vms;
} zDom0;

/**
 * Represents a virtual machine
 */
typedef struct t_zDomU {
	int id;
//	char uuid[37];
//	char name[256];
	char *uuid;
	char *name;
	zDom0 *dom0;
} zDomU;


/**
 * Defines the wrapper API for Internal job types.
 */
typedef struct t_zInternalJobType {
	/* name of the module. Based on file name */
	char name[256];

	/* reference to the descriptor that the module loaded from */
	void *library;
	
	/* configuration data provided by init call */
	void *config;
	
	/* initialization function. Called once */
	void *(*init)(void);
	
	/* execute a job. Actual signature is:
	 * 
	 *    int zJob_Execute(void *config, zList *run_list, zList *thread_list, zJob *job)
	 */
	int (*execute)(void *, zList *, zList *, zJob *);
	
	/* describes how long the execution is expected to take. Used for scheduling purposes */
	int (*speed)(void *, zJob*);
	
	/* cleanup function. Called once when exiting */
	int (*uninit)(void *);
} zInternalJobType;

/**
 * Defines the wrapper API for Addon job types.
 */
typedef struct t_zAddonJobType {
	/* Name of the module. Based on file name. */
	char name[256];

	/* reference to the descriptor that the module loaded from */
	void *library;
	
	/* configuration data provided by init call */
	void *config;
	
	/* initialization function. Called once */
	void *(*init)(void);
	
	/* execute a job. Actual signature is:
	 * 
	 *    int zJob_Execute(void *config, zJob *job)
	 */
	int (*execute)(void *, zJob *);
	
	/* describes how long the execution is expected to take. Used for scheduling purposes */
	int (*speed)(void *, zJob*);
	
	/* cleanup function. Called once when exiting */
	int (*uninit)(void *);
} zAddonJobType;

/**
 * Represents a worker thread in the list of workers
 */
typedef struct t_zWorker {
	/* ID of the thread that this represents */
	pthread_t thread_id;
	
	/* Job currently being executed by this thread */
	zJob *current_job;
} zWorker;

/**
 * Loads all internal job types and calls their initialization scripts. Returns a list of
 * zInternalJobType variables.
 * 
 * Returns NULL if there was an error.
 */
zList *z_InitInternalJobTypes();

/**
 * Loads all addon job types and calls their initialization scripts. Returns a list of
 * zInternalJobType variables.
 * 
 * Returns NULL if there was an error.
 */
zList *z_InitAddonJobTypes();

/**
 * Unloads all sources via their uninit functions. Works on both internal and
 */
int z_UninitJobTypes(zList *jobtypes);

/**
 * Executes a job
 */
int z_ExecuteJob(zJob *job, zList *internalList, zList *addonList, zList* runList, zList* threadList);

/**
 * Calculate the estimated execution speed of a job
 */
int z_JobSpeed(zJob *job, zList *addonList, zList *internalList);

#endif // ZENTIFIC_TYPES_H