/*
 *
 *   Copyright (c) International Business Machines  Corp., 2001
 *   Copyright (C) 1997-1999 David Mosberger-Tang and Andreas Beck
 *
 *   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
 *
 * Module: options.h
 */

#ifndef EVMS_OPTIONS_H_INCLUDED
#define EVMS_OPTIONS_H_INCLUDED 1

#include <common.h>

/*
 * Dear Reader,
 *
 * Yes, some of the structures look a lot like the ones the SANE
 * (Scanner Access Now Easy) folks use for negotiating options
 * between a frontend and backend. In fact, some of the structures
 * here were derived from their solution with some tweaks for EVMS.
 *
 * Kindest regards and most humble apologies to the SANE folks for
 * borrowing their solution.
 */

/*
 * Task API typedefs
 */

typedef u_int32_t task_handle_t;

/*
 * Task actions correspond to the low-level API available to frontends.
 * The task API allows binding of action, plugin, target objects, and
 * plugin-specific options. This allows for interaction with the backend
 * to validate the correctness of parameters and options necessary to
 * fulfill the requirements of the low-level API which eventually is invoked.
 */

typedef enum {
    EVMS_Task_Create = 0,
    EVMS_Task_Create_Container,
    EVMS_Task_Assign_Plugin,
    EVMS_Task_Expand_Container,
    EVMS_Task_Set_Info,
    EVMS_Task_Expand,
    EVMS_Task_Shrink,
    EVMS_Task_Slide,
    EVMS_Task_Move,
    EVMS_Task_mkfs,
    EVMS_Task_fsck,
    EVMS_Task_defrag,
    EVMS_Task_Message
} task_action_t;

/*
 * Parameter API typedefs
 */

typedef struct declined_handle_s {
    object_handle_t           handle;               /* Handle of object declined */
    int                       reason;               /* Reason for being declined */
} declined_handle_t;

typedef struct declined_handle_array_s {
    uint                      count;
    declined_handle_t         declined[1];
} declined_handle_array_t;

/*
 * Option API typedefs and constants
 */

typedef enum {
    EVMS_Type_String = 1,                           /* char*     */
    EVMS_Type_Boolean,                              /* BOOLEAN   */
    EVMS_Type_Char,                                 /* char      */
    EVMS_Type_Unsigned_Char,                        /* unsigned char */
    EVMS_Type_Real32,                               /* float     */
    EVMS_Type_Real64,                               /* double    */
    EVMS_Type_Int,                                  /* int       */
    EVMS_Type_Int8,                                 /* int8_t    */
    EVMS_Type_Int16,                                /* int16_t   */
    EVMS_Type_Int32,                                /* int32_t   */
    EVMS_Type_Int64,                                /* int64_t   */
    EVMS_Type_Unsigned_Int,                         /* uint      */
    EVMS_Type_Unsigned_Int8,                        /* u_int8_t  */
    EVMS_Type_Unsigned_Int16,                       /* u_int16_t */
    EVMS_Type_Unsigned_Int32,                       /* u_int32_t */
    EVMS_Type_Unsigned_Int64                        /* u_int64_t */
} value_type_t;

typedef enum {
    EVMS_Unit_None = 0,
    EVMS_Unit_Disks,
    EVMS_Unit_Sectors,
    EVMS_Unit_Segments,
    EVMS_Unit_Regions,
    EVMS_Unit_Percent,
    EVMS_Unit_Milliseconds,
    EVMS_Unit_Microseconds,
    EVMS_Unit_Bytes,
    EVMS_Unit_Kilobytes,
    EVMS_Unit_Megabytes,
    EVMS_Unit_Gigabytes,
    EVMS_Unit_Terabytes,
    EVMS_Unit_Petabytes
} value_unit_t;

typedef enum {
    EVMS_Collection_None = 0,                       /* No collection */
    EVMS_Collection_List,                           /* Use a value_list_t structure */
    EVMS_Collection_Range                           /* Use a value_range_t structure */
} collection_type_t;

typedef union {
    char                      c;                    /* one character, e.g. 'C' */
    char                     *s;                    /* string pointer */
    u_char                    uc;
    int                       bool;
    int                       i;
    int8_t                    i8;
    int16_t                   i16;
    int32_t                   i32;
    int64_t                   i64;
    u_int                     ui;
    u_int8_t                  ui8;
    u_int16_t                 ui16;
    u_int32_t                 ui32;
    u_int64_t                 ui64;
    float                     r32;
    double                    r64;
    struct value_list_s      *list;
} value_t;

/*
 * The struct key_value_pair_s allows some generic passing
 * of a key/value pair for some basic data type values. The
 * key can be a name (a string) or a number. The sending
 * and receiving ends denote, through the is_number_based flag,
 * which key should be looked at for identification purposes.
 */

typedef struct key_value_pair_s {
    char           *name;                           /* Key if name-based */
    u_int16_t       number;                         /* Key if number-based */
    BOOLEAN         is_number_based;                /* TRUE if number-based */
    value_type_t    type;                           /* Value type */
    value_t         value;                          /* Union of basic data types */
} key_value_pair_t;

/*
 * Some frontends may supply plugin-specific data as "options" through
 * the API functions, e.g. evms_create(), available to a frontend.
 * Options are essentially key/value pairs where the key and value types
 * are known ahead-of-time or were interrogated through the option
 * descriptor API.
 */

typedef struct option_array_s {
    u_int                     count;
    key_value_pair_t          option[1];
} option_array_t;

typedef struct value_list_s {
    u_int                     count;
    value_t                   value[1];
} value_list_t;

typedef struct value_range_s {
    value_t                   min;                  /* Minimum value */
    value_t                   max;                  /* Maximum value */
    value_t                   increment;            /* Step or increment for changes in-between */
} value_range_t;

typedef union {
    value_list_t             *list;                 /* Array of values of the same type */
    value_range_t            *range;                /* Range of values for numeric types */
} value_collection_t;

typedef struct group_info_s {
    u_int32_t                 group_number;         /* group number, 0 if not grouped */
    u_int32_t                 group_level;          /* possibly used for indenting, or sub fields */
    char                     *group_name;           /* name of group                              */
} group_info_t;

typedef struct option_descriptor_s {
    char                     *name;                 /* Option name/key */
    char                     *title;                /* One or two word description of option */
    char                     *tip;                  /* Multi-sentence description of option for tip */
    char                     *help;                 /* Multi-paragraph detailed option help */
    value_type_t              type;                 /* Defines option data type */
    value_unit_t              unit;                 /* Defines unit value */
    u_int32_t                 size;                 /* Maximum size (in bytes) of option value */
    u_int64_t                 flags;                /* Option flags (defined below) */
    collection_type_t         constraint_type;      /* Constraint type (none, range, list) */
    value_collection_t        constraint;           /* Either a list or range of valid input values */
    value_t                   value;                /* Initial/current value */
    group_info_t              group;                /* Group information for display purposes     */
} option_descriptor_t;

/*
 * option_descriptor_t flags bitset
 */

#define EVMS_OPTION_FLAGS_NOT_REQUIRED     (1 << 0) /* A key_value_pair_t for this option can be provided */
                                                    /* but is not absolutely required by the plug-in */
#define EVMS_OPTION_FLAGS_NO_INITIAL_VALUE (1 << 1) /* The plug-in has not provided an initial value */
#define EVMS_OPTION_FLAGS_AUTOMATIC        (1 << 2) /* Backend is capable of selecting reasonable value */
#define EVMS_OPTION_FLAGS_INACTIVE         (1 << 3) /* Option exists but is neither optional or required */
#define EVMS_OPTION_FLAGS_ADVANCED         (1 << 4) /* Option is an "advanced user option" */
#define EVMS_OPTION_FLAGS_VALUE_IS_LIST    (1 << 5) /* Value is/is expected to be a pointer to value_list_t */
#define EVMS_OPTION_FLAGS_NO_UNIT_CONVERSION (1 << 6) /* Don't convert unit measurements, e.g. I really mean */
                                                      /* to have the user specify/see sectors not KB or MB */

#define EVMS_OPTION_IS_ACTIVE(flags)     (((flags) & EVMS_OPTION_FLAGS_INACTIVE) == 0)
#define EVMS_OPTION_IS_REQUIRED(flags)   (((flags) & EVMS_OPTION_FLAGS_NOT_REQUIRED) == 0)
#define EVMS_OPTION_HAS_VALUE(flags)     (((flags) & EVMS_OPTION_FLAGS_NO_INITIAL_VALUE) == 0)
#define EVMS_OPTION_VALUE_IS_LIST(flags) (((flags) & EVMS_OPTION_FLAGS_VALUE_IS_LIST) != 0)

/*
 * Following bitset indicating additional information of
 * the outcome of a set_object or a set action on a option value.
 */

typedef enum {
    EVMS_Effect_Inexact        = (1 << 0),       /* Option value was adjusted by backend */
    EVMS_Effect_Reload_Options = (1 << 1),       /* Setting of an object or option has affected */
                                                 /* the value or availability of other options */
    EVMS_Effect_Reload_Objects = (1 << 2)        /* Setting of an object or option has affected */
                                                 /* the acceptable and/or selected objects */
                                                 /* or the limits of objects selected. */
} task_effect_t;

/*
 * Extended information structure. Plug-ins generate an
 * array of these to supply plugin-specific information.
 * They are similar to option descriptors but lighter.
 */

typedef enum {
    EVMS_Format_Normal = 0,
    EVMS_Format_Hex,
    EVMS_Format_Ascii,
    EVMS_Format_Binary
} value_format_t;

typedef struct extended_info_s {
    char                   *name;                   /* Info field name */
    char                   *title;                  /* One or two word description of info field */
    char                   *desc;                   /* Multi-sentence description of info field */
    value_type_t            type;                   /* Defines info data type */
    value_unit_t            unit;                   /* Defines info unit value */
    value_format_t          format;                 /* Suggested format for display of values */
    value_t                 value;                  /* Single value if not a collection */
    collection_type_t       collection_type;        /* Defines if either a list or range of values */
    value_collection_t      collection;             /* Either a list or range of values of value_type_t */
    group_info_t            group;                  /* Group information for display purposes */
    u_int16_t               flags;                  /* Extended info flags (defined below) */
} extended_info_t;

#define EVMS_EINFO_FLAGS_NO_UNIT_CONVERSION (1 << 0) /* Don't convert unit measurements, e.g. I really */
                                                     /* mean the user to see sectors not KB or MB */
#define EVMS_EINFO_FLAGS_MORE_INFO_AVAILABLE (1 << 1)/* This entry has more information if */
                                                     /* queried by name. */

typedef struct extended_info_array_s {
    u_int                   count;                  /* Count of extended_info_t structs in array */
    extended_info_t         info[1];                /* Info descriptors */
} extended_info_array_t;

#endif