/*
 * Asterisk -- An open source telephony toolkit.
 *
 * Copyright (C) 1999 - 2005, Digium, Inc.
 *
 * Mark Spencer <markster@digium.com>
 *
 * See http://www.asterisk.org for more information about
 * the Asterisk project. Please do not directly contact
 * any of the maintainers of this project for assistance;
 * the project provides a web site, mailing lists and IRC
 * channels for your use.
 *
 * This program is free software, distributed under the terms of
 * the GNU General Public License Version 2. See the LICENSE file
 * at the top of the source tree.
 */

/*! \file
 * \brief Core PBX routines and definitions.
 */

#ifndef _ASTERISK_PBX_H
#define _ASTERISK_PBX_H

#include "asterisk/sched.h"
#include "asterisk/channel.h"

#if defined(__cplusplus) || defined(c_plusplus)
extern "C" {
#endif

#define AST_PBX_KEEP    0
#define AST_PBX_REPLACE 1

/*! Max length of an application */
#define AST_MAX_APP	32

/*! Special return values from applications to the PBX */
#define AST_PBX_KEEPALIVE	10		/* Destroy the thread, but don't hang up the channel */
#define AST_PBX_NO_HANGUP_PEER       11

/*! Special Priority for an hint */
#define PRIORITY_HINT	-1

/*! Extension states */
enum ast_extension_states {
	/*! Extension removed */
	AST_EXTENSION_REMOVED = -2,
	/*! Extension hint removed */
	AST_EXTENSION_DEACTIVATED = -1,
	/*! No device INUSE or BUSY  */
	AST_EXTENSION_NOT_INUSE = 0,
	/*! One or more devices INUSE */
	AST_EXTENSION_INUSE = 1 << 0,
	/*! All devices BUSY */
	AST_EXTENSION_BUSY = 1 << 1,
	/*! All devices UNAVAILABLE/UNREGISTERED */
	AST_EXTENSION_UNAVAILABLE = 1 << 2,
	/*! All devices RINGING */
	AST_EXTENSION_RINGING = 1 << 3,
};


static const struct cfextension_states {
	int extension_state;
	const char * const text;
} extension_states[] = {
	{ AST_EXTENSION_NOT_INUSE,                     "Idle" },
	{ AST_EXTENSION_INUSE,                         "InUse" },
	{ AST_EXTENSION_BUSY,                          "Busy" },
	{ AST_EXTENSION_UNAVAILABLE,                   "Unavailable" },
	{ AST_EXTENSION_RINGING,                       "Ringing" },
	{ AST_EXTENSION_INUSE | AST_EXTENSION_RINGING, "InUse&Ringing" }
};

struct ast_context;
struct ast_exten;     
struct ast_include;
struct ast_ignorepat;
struct ast_sw;

typedef int (*ast_state_cb_type)(char *context, char* id, enum ast_extension_states state, void *data);

/*! Data structure associated with a custom function */
struct ast_custom_function {
	char *name;
	char *synopsis;
	char *desc;
	char *syntax;
	char *(*read)(struct ast_channel *, char *, char *, char *, size_t);
	void (*write)(struct ast_channel *, char *, char *, const char *);
	struct ast_custom_function *next;
};

/*! Data structure associated with an asterisk switch */
struct ast_switch {
	/*! NULL */
	struct ast_switch *next;	
	/*! Name of the switch */
	const char *name;				
	/*! Description of the switch */
	const char *description;		
	
	int (*exists)(struct ast_channel *chan, const char *context, const char *exten, int priority, const char *callerid, const char *data);
	
	int (*canmatch)(struct ast_channel *chan, const char *context, const char *exten, int priority, const char *callerid, const char *data);
	
	int (*exec)(struct ast_channel *chan, const char *context, const char *exten, int priority, const char *callerid, int newstack, const char *data);

	int (*matchmore)(struct ast_channel *chan, const char *context, const char *exten, int priority, const char *callerid, const char *data);
};

struct ast_timing {
	int hastime;				/* If time construct exists */
	unsigned int monthmask;			/* Mask for month */
	unsigned int daymask;			/* Mask for date */
	unsigned int dowmask;			/* Mask for day of week (mon-sun) */
	unsigned int minmask[24];		/* Mask for minute */
};

extern int ast_build_timing(struct ast_timing *i, char *info);
extern int ast_check_timing(struct ast_timing *i);

struct ast_pbx {
        int dtimeout;                                   /* Timeout between digits (seconds) */
        int rtimeout;                                   /* Timeout for response
							   (seconds) */
};


/*! Register an alternative switch */
/*!
 * \param sw switch to register
 * This function registers a populated ast_switch structure with the
 * asterisk switching architecture.
 * It returns 0 on success, and other than 0 on failure
 */
extern int ast_register_switch(struct ast_switch *sw);

/*! Unregister an alternative switch */
/*!
 * \param sw switch to unregister
 * Unregisters a switch from asterisk.
 * Returns nothing
 */
extern void ast_unregister_switch(struct ast_switch *sw);

/*! Look up an application */
/*!
 * \param app name of the app
 * This function searches for the ast_app structure within
 * the apps that are registered for the one with the name
 * you passed in.
 * Returns the ast_app structure that matches on success, or NULL on failure
 */
extern struct ast_app *pbx_findapp(const char *app);

/*! executes an application */
/*!
 * \param c channel to execute on
 * \param app which app to execute
 * \param data the data passed into the app
 * \param newstack stack pointer
 * This application executes an application on a given channel.  It
 * saves the stack and executes the given appliation passing in
 * the given data.
 * It returns 0 on success, and -1 on failure
 */
int pbx_exec(struct ast_channel *c, struct ast_app *app, void *data, int newstack);

/*! Register a new context */
/*!
 * \param extcontexts pointer to the ast_context structure pointer
 * \param name name of the new context
 * \param registrar registrar of the context
 * This will first search for a context with your name.  If it exists already, it will not
 * create a new one.  If it does not exist, it will create a new one with the given name
 * and registrar.
 * It returns NULL on failure, and an ast_context structure on success
 */
struct ast_context *ast_context_create(struct ast_context **extcontexts, const char *name, const char *registrar);

/*! Merge the temporary contexts into a global contexts list and delete from the global list the ones that are being added */
/*!
 * \param extcontexts pointer to the ast_context structure pointer
 * \param registrar of the context; if it's set the routine will delete all contexts that belong to that registrar; if NULL only the contexts that are specified in extcontexts
 */
void ast_merge_contexts_and_delete(struct ast_context **extcontexts, const char *registrar);

/*! Destroy a context (matches the specified context (or ANY context if NULL) */
/*!
 * \param con context to destroy
 * \param registrar who registered it
 * You can optionally leave out either parameter.  It will find it
 * based on either the ast_context or the registrar name.
 * Returns nothing
 */
void ast_context_destroy(struct ast_context *con, const char *registrar);

/*! Find a context */
/*!
 * \param name name of the context to find
 * Will search for the context with the given name.
 * Returns the ast_context on success, NULL on failure.
 */
struct ast_context *ast_context_find(const char *name);

enum ast_pbx_result {
	AST_PBX_SUCCESS = 0,
	AST_PBX_FAILED = -1,
	AST_PBX_CALL_LIMIT = -2,
};

/*! Create a new thread and start the PBX (or whatever) */
/*!
 * \param c channel to start the pbx on
 * \return Zero on success, non-zero on failure
 */
enum ast_pbx_result ast_pbx_start(struct ast_channel *c);

/*! Execute the PBX in the current thread */
/*!
 * \param c channel to run the pbx on
 * \return Zero on success, non-zero on failure
 * This executes the PBX on a given channel. It allocates a new
 * PBX structure for the channel, and provides all PBX functionality.
 */
enum ast_pbx_result ast_pbx_run(struct ast_channel *c);

/*! 
 * \param context context to add the extension to
 * \param replace
 * \param extension extension to add
 * \param priority priority level of extension addition
 * \param label extension label
 * \param callerid callerid of extension
 * \param application application to run on the extension with that priority level
 * \param data data to pass to the application
 * \param datad
 * \param registrar who registered the extension
 * Add and extension to an extension context.  
 * Callerid is a pattern to match CallerID, or NULL to match any callerid
 * Returns 0 on success, -1 on failure
 */
int ast_add_extension(const char *context, int replace, const char *extension, int priority, const char *label, const char *callerid,
	const char *application, void *data, void (*datad)(void *), const char *registrar);

/*! Add an extension to an extension context, this time with an ast_context *.  CallerID is a pattern to match on callerid, or NULL to not care about callerid */
/*! 
 * For details about the arguements, check ast_add_extension()
 */
int ast_add_extension2(struct ast_context *con,
				      int replace, const char *extension, int priority, const char *label, const char *callerid, 
					  const char *application, void *data, void (*datad)(void *),
					  const char *registrar);

/*! Add an application.  The function 'execute' should return non-zero if the line needs to be hung up.  */
/*!
  \param app Short name of the application
  \param execute a function callback to execute the application
  \param synopsis a short description of the application
  \param description long description of the application
   Include a one-line synopsis (e.g. 'hangs up a channel') and a more lengthy, multiline
   description with more detail, including under what conditions the application
   will return 0 or -1.
   This registers an application with asterisks internal application list.  Please note:
   The individual applications themselves are responsible for registering and unregistering
   CLI commands.
   It returns 0 on success, -1 on failure.
*/
int ast_register_application(const char *app, int (*execute)(struct ast_channel *, void *),
			     const char *synopsis, const char *description);

/*! Remove an application */
/*!
 * \param app name of the application (does not have to be the same string as the one that was registered)
 * This unregisters an application from asterisk's internal registration mechanisms.
 * It returns 0 on success, and -1 on failure.
 */
int ast_unregister_application(const char *app);

/*! Uses hint and devicestate callback to get the state of an extension */
/*!
 * \param c this is not important
 * \param context which context to look in
 * \param exten which extension to get state
 * Returns extension state !! = AST_EXTENSION_???
 */
int ast_extension_state(struct ast_channel *c, char *context, char *exten);

/*! Return string of the state of an extension */
/*!
 * \param extension_state is the numerical state delivered by ast_extension_state
 * Returns the state of an extension as string
 */
const char *ast_extension_state2str(int extension_state);

/*! Registers a state change callback */
/*!
 * \param context which context to look in
 * \param exten which extension to get state
 * \param callback callback to call if state changed
 * \param data to pass to callback
 * The callback is called if the state for extension is changed
 * Return -1 on failure, ID on success
 */ 
int ast_extension_state_add(const char *context, const char *exten, 
			    ast_state_cb_type callback, void *data);

/*! Deletes a registered state change callback by ID */
/*!
 * \param id of the callback to delete
 * \param callback callback
 * Removes the callback from list of callbacks
 * Return 0 on success, -1 on failure
 */
int ast_extension_state_del(int id, ast_state_cb_type callback);

/*! If an extension exists, return non-zero */
/*!
 * \param hint buffer for hint
 * \param maxlen size of hint buffer
 * \param name buffer for name portion of hint
 * \param maxnamelen size of name buffer
 * \param c this is not important
 * \param context which context to look in
 * \param exten which extension to search for
 * If an extension within the given context with the priority PRIORITY_HINT
 * is found a non zero value will be returned.
 * Otherwise, 0 is returned.
 */
int ast_get_hint(char *hint, int maxlen, char *name, int maxnamelen, struct ast_channel *c, const char *context, const char *exten);

/*! If an extension exists, return non-zero */
/*  work */
/*!
 * \param c this is not important
 * \param context which context to look in
 * \param exten which extension to search for
 * \param priority priority of the action within the extension
 * \param callerid callerid to search for
 * If an extension within the given context(or callerid) with the given priority is found a non zero value will be returned.
 * Otherwise, 0 is returned.
 */
int ast_exists_extension(struct ast_channel *c, const char *context, const char *exten, int priority, const char *callerid);

/*! If an extension exists, return non-zero */
/*  work */
/*!
 * \param c this is not important
 * \param context which context to look in
 * \param exten which extension to search for
 * \param label label of the action within the extension to match to priority
 * \param callerid callerid to search for
 * If an priority which matches given label in extension or -1 if not found.
\ */
int ast_findlabel_extension(struct ast_channel *c, const char *context, const char *exten, const char *label, const char *callerid);

int ast_findlabel_extension2(struct ast_channel *c, struct ast_context *con, const char *exten, const char *label, const char *callerid);

/*! Looks for a valid matching extension */
/*!
  \param c not really important
  \param context context to serach within
  \param exten extension to check
  \param priority priority of extension path
  \param callerid callerid of extension being searched for
   If "exten" *could be* a valid extension in this context with or without
   some more digits, return non-zero.  Basically, when this returns 0, no matter
   what you add to exten, it's not going to be a valid extension anymore
*/
int ast_canmatch_extension(struct ast_channel *c, const char *context, const char *exten, int priority, const char *callerid);

/*! Looks to see if adding anything to this extension might match something. (exists ^ canmatch) */
/*!
  \param c not really important
  \param context context to serach within
  \param exten extension to check
  \param priority priority of extension path
  \param callerid callerid of extension being searched for
   If "exten" *could match* a valid extension in this context with
   some more digits, return non-zero.  Does NOT return non-zero if this is
   an exact-match only.  Basically, when this returns 0, no matter
   what you add to exten, it's not going to be a valid extension anymore
*/
int ast_matchmore_extension(struct ast_channel *c, const char *context, const char *exten, int priority, const char *callerid);

/*! Determine if a given extension matches a given pattern (in NXX format) */
/*!
 * \param pattern pattern to match
 * \param extension extension to check against the pattern.
 * Checks whether or not the given extension matches the given pattern.
 * Returns 1 on match, 0 on failure
 */
int ast_extension_match(const char *pattern, const char *extension);
int ast_extension_close(const char *pattern, const char *data, int needmore);
/*! Launch a new extension (i.e. new stack) */
/*!
 * \param c not important
 * \param context which context to generate the extension within
 * \param exten new extension to add
 * \param priority priority of new extension
 * \param callerid callerid of extension
 * This adds a new extension to the asterisk extension list.
 * It returns 0 on success, -1 on failure.
 */
int ast_spawn_extension(struct ast_channel *c, const char *context, const char *exten, int priority, const char *callerid);

/*! Execute an extension. */
/*!
  \param c channel to execute upon
  \param context which context extension is in
  \param exten extension to execute
  \param priority priority to execute within the given extension
  \param callerid Caller-ID
   If it's not available, do whatever you should do for
   default extensions and halt the thread if necessary.  This function does not
   return, except on error.
*/
int ast_exec_extension(struct ast_channel *c, const char *context, const char *exten, int priority, const char *callerid);

/*! Add an include */
/*!
  \param context context to add include to
  \param include new include to add
  \param registrar who's registering it
   Adds an include taking a char * string as the context parameter
   Returns 0 on success, -1 on error
*/
int ast_context_add_include(const char *context, const char *include, const char *registrar);

/*! Add an include */
/*!
  \param con context to add the include to
  \param include include to add
  \param registrar who registered the context
   Adds an include taking a struct ast_context as the first parameter
   Returns 0 on success, -1 on failure
*/
int ast_context_add_include2(struct ast_context *con, const char *include, const char *registrar);

/*! Removes an include */
/*!
 * See add_include
 */
int ast_context_remove_include(const char *context, const char *include,const  char *registrar);
/*! Removes an include by an ast_context structure */
/*!
 * See add_include2
 */
int ast_context_remove_include2(struct ast_context *con, const char *include, const char *registrar);

/*! Verifies includes in an ast_contect structure */
/*!
 * \param con context in which to verify the includes
 * Returns 0 if no problems found, -1 if there were any missing context
 */
int ast_context_verify_includes(struct ast_context *con);
	  
/*! Add a switch */
/*!
 * \param context context to which to add the switch
 * \param sw switch to add
 * \param data data to pass to switch
 * \param eval whether to evaluate variables when running switch
 * \param registrar whoever registered the switch
 * This function registers a switch with the asterisk switch architecture
 * It returns 0 on success, -1 on failure
 */
int ast_context_add_switch(const char *context, const char *sw, const char *data, int eval, const char *registrar);
/*! Adds a switch (first param is a ast_context) */
/*!
 * See ast_context_add_switch()
 */
int ast_context_add_switch2(struct ast_context *con, const char *sw, const char *data, int eval, const char *registrar);

/*! Remove a switch */
/*!
 * Removes a switch with the given parameters
 * Returns 0 on success, -1 on failure
 */
int ast_context_remove_switch(const char *context, const char *sw, const char *data, const char *registrar);
int ast_context_remove_switch2(struct ast_context *con, const char *sw, const char *data, const char *registrar);

/*! Simply remove extension from context */
/*!
 * \param context context to remove extension from
 * \param extension which extension to remove
 * \param priority priority of extension to remove
 * \param registrar registrar of the extension
 * This function removes an extension from a given context.
 * Returns 0 on success, -1 on failure
 */
int ast_context_remove_extension(const char *context, const char *extension, int priority,
	const char *registrar);
int ast_context_remove_extension2(struct ast_context *con, const char *extension,
	int priority, const char *registrar);

/*! Add an ignorepat */
/*!
 * \param context which context to add the ignorpattern to
 * \param ignorepat ignorepattern to set up for the extension
 * \param registrar registrar of the ignore pattern
 * Adds an ignore pattern to a particular context.
 * Returns 0 on success, -1 on failure
 */
int ast_context_add_ignorepat(const char *context, const char *ignorepat, const char *registrar);
int ast_context_add_ignorepat2(struct ast_context *con, const char *ignorepat, const char *registrar);

/* Remove an ignorepat */
/*!
 * \param context context from which to remove the pattern
 * \param ignorepat the pattern to remove
 * \param registrar the registrar of the ignore pattern
 * This removes the given ignorepattern
 * Returns 0 on success, -1 on failure
 */
int ast_context_remove_ignorepat(const char *context, const char *ignorepat, const char *registrar);
int ast_context_remove_ignorepat2(struct ast_context *con, const char *ignorepat, const char *registrar);

/*! Checks to see if a number should be ignored */
/*!
 * \param context context to search within
 * \param pattern to check whether it should be ignored or not
 * Check if a number should be ignored with respect to dialtone cancellation.  
 * Returns 0 if the pattern should not be ignored, or non-zero if the pattern should be ignored 
 */
int ast_ignore_pattern(const char *context, const char *pattern);

/* Locking functions for outer modules, especially for completion functions */
/*! Locks the contexts */
/*! Locks the context list
 * Returns 0 on success, -1 on error
 */
int ast_lock_contexts(void);

/*! Unlocks contexts */
/*!
 * Returns 0 on success, -1 on failure
 */
int ast_unlock_contexts(void);

/*! Locks a given context */
/*!
 * \param con context to lock
 * Locks the context.
 * Returns 0 on success, -1 on failure
 */
int ast_lock_context(struct ast_context *con);
/*! Unlocks the given context */
/*!
 * \param con context to unlock
 * Unlocks the given context
 * Returns 0 on success, -1 on failure
 */
int ast_unlock_context(struct ast_context *con);


int ast_async_goto(struct ast_channel *chan, const char *context, const char *exten, int priority);

int ast_async_goto_by_name(const char *chan, const char *context, const char *exten, int priority);

/* Synchronously or asynchronously make an outbound call and send it to a
   particular extension */
int ast_pbx_outgoing_exten(const char *type, int format, void *data, int timeout, const char *context, const char *exten, int priority, int *reason, int sync, const char *cid_num, const char *cid_name, struct ast_variable *vars, const char *account, struct ast_channel **locked_channel);

/* Synchronously or asynchronously make an outbound call and send it to a
   particular application with given extension */
int ast_pbx_outgoing_app(const char *type, int format, void *data, int timeout, const char *app, const char *appdata, int *reason, int sync, const char *cid_num, const char *cid_name, struct ast_variable *vars, const char *account, struct ast_channel **locked_channel);

/* Evaluate a condition for non-falseness and return a boolean */
int pbx_checkcondition(char *condition);

/* Functions for returning values from structures */
const char *ast_get_context_name(struct ast_context *con);
const char *ast_get_extension_name(struct ast_exten *exten);
const char *ast_get_include_name(struct ast_include *include);
const char *ast_get_ignorepat_name(struct ast_ignorepat *ip);
const char *ast_get_switch_name(struct ast_sw *sw);
const char *ast_get_switch_data(struct ast_sw *sw);

/* Other extension stuff */
int ast_get_extension_priority(struct ast_exten *exten);
int ast_get_extension_matchcid(struct ast_exten *e);
const char *ast_get_extension_cidmatch(struct ast_exten *e);
const char *ast_get_extension_app(struct ast_exten *e);
const char *ast_get_extension_label(struct ast_exten *e);
void *ast_get_extension_app_data(struct ast_exten *e);

/* Registrar info functions ... */
const char *ast_get_context_registrar(struct ast_context *c);
const char *ast_get_extension_registrar(struct ast_exten *e);
const char *ast_get_include_registrar(struct ast_include *i);
const char *ast_get_ignorepat_registrar(struct ast_ignorepat *ip);
const char *ast_get_switch_registrar(struct ast_sw *sw);

/* Walking functions ... */
struct ast_context *ast_walk_contexts(struct ast_context *con);
struct ast_exten *ast_walk_context_extensions(struct ast_context *con,
	struct ast_exten *priority);
struct ast_exten *ast_walk_extension_priorities(struct ast_exten *exten,
	struct ast_exten *priority);
struct ast_include *ast_walk_context_includes(struct ast_context *con,
	struct ast_include *inc);
struct ast_ignorepat *ast_walk_context_ignorepats(struct ast_context *con,
	struct ast_ignorepat *ip);
struct ast_sw *ast_walk_context_switches(struct ast_context *con, struct ast_sw *sw);

int pbx_builtin_serialize_variables(struct ast_channel *chan, char *buf, size_t size);
extern char *pbx_builtin_getvar_helper(struct ast_channel *chan, const char *name);
extern void pbx_builtin_pushvar_helper(struct ast_channel *chan, const char *name, const char *value);
extern void pbx_builtin_setvar_helper(struct ast_channel *chan, const char *name, const char *value);
extern void pbx_retrieve_variable(struct ast_channel *c, const char *var, char **ret, char *workspace, int workspacelen, struct varshead *headp);
extern void pbx_builtin_clear_globals(void);
extern int pbx_builtin_setvar(struct ast_channel *chan, void *data);
extern void pbx_substitute_variables_helper(struct ast_channel *c,const char *cp1,char *cp2,int count);
extern void pbx_substitute_variables_varshead(struct varshead *headp, const char *cp1, char *cp2, int count);

int ast_extension_patmatch(const char *pattern, const char *data);

/* Set "autofallthrough" flag, if newval is <0, does not acutally set.  If
  set to 1, sets to auto fall through.  If newval set to 0, sets to no auto
  fall through (reads extension instead).  Returns previous value. */
extern int pbx_set_autofallthrough(int newval);
int ast_goto_if_exists(struct ast_channel *chan, char* context, char *exten, int priority);
/* I can find neither parsable nor parseable at dictionary.com, but google gives me 169000 hits for parseable and only 49,800 for parsable */
int ast_parseable_goto(struct ast_channel *chan, const char *goto_string);
int ast_explicit_goto(struct ast_channel *chan, const char *context, const char *exten, int priority);
int ast_async_goto_if_exists(struct ast_channel *chan, char* context, char *exten, int priority);

struct ast_custom_function* ast_custom_function_find(char *name);
int ast_custom_function_unregister(struct ast_custom_function *acf);
int ast_custom_function_register(struct ast_custom_function *acf);

/* Number of active calls */
int ast_active_calls(void);
	
/*! executes a read operation on a function */
/*!
 * \param chan Channel to execute on
 * \param in Data containing the function call string
 * \param workspace A pointer to safe memory to use for a return value 
 * \param len the number of bytes in workspace
 * This application executes an function in read mode on a given channel.
 * It returns a pointer to workspace if the buffer contains any new data
 * or NULL if there was a problem.
 */
	
char *ast_func_read(struct ast_channel *chan, const char *in, char *workspace, size_t len);

/*! executes a write operation on a function */
/*!
 * \param chan Channel to execute on
 * \param in Data containing the function call string
 * \param value A value parameter to pass for writing
 * This application executes an function in write mode on a given channel.
 * It has no return value.
 */
void ast_func_write(struct ast_channel *chan, const char *in, const char *value);

void ast_hint_state_changed(const char *device);

#if defined(__cplusplus) || defined(c_plusplus)
}
#endif

#endif /* _ASTERISK_PBX_H */