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Class that holds a tree of availability conditions.

Copyright: 2014 The Open University
License: http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
File Size: 797 lines (30 kb)
Included or required:0 times
Referenced: 0 times
Includes or requires: 0 files

Defines 1 class


Class: tree  - X-Ref

Class that holds a tree of availability conditions.

The structure of this tree in JSON input data is:

{ op:'&', c:[] }

where 'op' is one of the OP_xx constants and 'c' is an array of children.

At the root level one of the following additional values must be included:

op '|' or '!&'
show:true
Boolean value controlling whether a failed match causes the item to
display to students with information, or be completely hidden.
op '&' or '!|'
showc:[]
Array of same length as c with booleans corresponding to each child; you
can make it be hidden or shown depending on which one they fail. (Anything
with false takes precedence.)

__toString()   X-Ref
Display a representation of this tree (used for debugging).

return: string Text representation of tree

__construct($structure, $lax = false, $root = true)   X-Ref
Decodes availability structure.

This function also validates the retrieved data as follows:
1. Data that does not meet the API-defined structure causes a
coding_exception (this should be impossible unless there is
a system bug or somebody manually hacks the database).
2. Data that meets the structure but cannot be implemented (e.g.
reference to missing plugin or to module that doesn't exist) is
either silently discarded (if $lax is true) or causes a
coding_exception (if $lax is false).

param: \stdClass $structure Structure (decoded from JSON)
param: boolean $lax If true, throw exceptions only for invalid structure
param: boolean $root If true, this is the root tree
return: tree Availability tree

check_available($not, info $info, $grabthelot, $userid)   X-Ref
No description

is_applied_to_user_lists()   X-Ref
No description

filter_user_list(array $users, $not, info $info,capability_checker $checker)   X-Ref
Tests against a user list. Users who cannot access the activity due to
availability restrictions will be removed from the list.

This test ONLY includes conditions which are marked as being applied to
user lists. For example, group conditions are included but date
conditions are not included.

The function operates reasonably efficiently i.e. should not do per-user
database queries. It is however likely to be fairly slow.

param: array $users Array of userid => object
param: bool $not If tree's parent indicates it's being checked negatively
param: info $info Info about current context
param: capability_checker $checker Capability checker
return: array Filtered version of input array

get_user_list_sql($not, info $info, $onlyactive)   X-Ref
No description

is_available_for_all($not = false)   X-Ref
No description

get_full_information(info $info)   X-Ref
Gets full information about this tree (including all children) as HTML
for display to staff.

param: info $info Information about location of condition tree
return: string HTML data (empty string if none)

get_result_information(info $info, result $result)   X-Ref
Gets information about this tree corresponding to the given result
object. (In other words, only conditions which the student actually
fails will be shown - and nothing if display is turned off.)

param: info $info Information about location of condition tree
param: result $result Result object
return: string HTML data (empty string if none)

get_full_information_recursive($not, info $info, ?result $result, $root, $hidden = false)   X-Ref
Gets information about this tree (including all or selected children) as
HTML for display to staff or student.

param: bool $not True if there is a NOT in effect
param: info $info Information about location of condition tree
param: result|null $result Result object if this is a student display, else null
param: bool $root True if this is the root item
param: bool $hidden Staff display; true if this tree has show=false (from parent)
return: string|renderable Information to render

get_logic_flags($not)   X-Ref
Converts the operator for the tree into two flags used for computing
the result.

The 2 flags are $innernot (whether to set $not when calling for children)
and $andoperator (whether to use AND or OR operator to combine children).

param: bool $not Not flag passed to this tree
return: array Array of the 2 flags ($innernot, $andoperator)

save()   X-Ref
No description

is_empty()   X-Ref
Checks whether this tree is empty (contains no children).

return: boolean True if empty

get_all_children($classname)   X-Ref
Recursively gets all children of a particular class (you can use a base
class to get all conditions, or a specific class).

param: string $classname Full class name e.g. core_availability\condition
return: array Array of nodes of that type (flattened, not a tree any more)

recursive_get_all_children($classname, array &$result)   X-Ref
Internal function that implements get_all_children efficiently.

param: string $classname Full class name e.g. core_availability\condition
param: array $result Output array of nodes

update_after_restore($restoreid, $courseid,\base_logger $logger, $name)   X-Ref
No description

update_dependency_id($table, $oldid, $newid)   X-Ref
No description

get_nested_json(array $children, $op = self::OP_AND)   X-Ref
Returns a JSON object which corresponds to a tree.

Intended for unit testing, as normally the JSON values are constructed
by JavaScript code.

This function generates 'nested' (i.e. not root-level) trees.

param: array $children Array of JSON objects from component children
param: string $op Operator (tree::OP_xx)
return: stdClass JSON object

get_root_json(array $children, $op = self::OP_AND, $show = true)   X-Ref
Returns a JSON object which corresponds to a tree at root level.

Intended for unit testing, as normally the JSON values are constructed
by JavaScript code.

The $show parameter can be a boolean for all OP_xx options. For OP_AND
and OP_NOT_OR where you have individual show options, you can specify
a boolean (same for all) or an array.

param: array $children Array of JSON objects from component children
param: string $op Operator (tree::OP_xx)
param: bool|array $show Whether 'show' option is turned on (see above)
return: stdClass JSON object ready for encoding