@prefix rdf:        <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
@prefix rdfs:       <http://www.w3.org/2000/01/rdf-schema#> .
@prefix dc:         <http://purl.org/dc/elements/1.1/> .

# Trust Policy Language Namespace
@prefix :       <http://www.wiwiss.fu-berlin.de/suhl/bizer/TPL/> .

# -----------------------------------------------
# About this document
# -----------------------------------------------

<>  rdfs:label       "Trust Policy Language Vocabulary (TPL)" ;
    rdfs:comment     "RDFS specification of the Trust Policy Language Vocabulary (TPL), a vocabulary used for defining trust policies to be used with TriQL Trust Layer" ;
    dc:creator       "Chris Bizer" ;
    dc:contributor   "Richard Cyganiak" ;
    dc:date          "2005-01-31" ;
    dc:format        "application/n3" ;
    .


# -----------------------------------------------
# Trust Policy Suite
# -----------------------------------------------

:TrustPolicySuite   rdf:type rdfs:Class ;
                    rdfs:label "Trust policy suite" ;
                    rdfs:comment "A set of TPL trust policies" 
                    .
:suiteName          rdf:type rdf:Property ;
                    rdfs:label "suite name" ;
                    rdfs:comment "A policy suite's name" ;
                    rdfs:domain :TrustPolicySuite
                    .
:includesPolicy     rdf:type rdf:Property ;
                    rdfs:label "includes policy" ;
                    rdfs:comment "Links a TrustPolicySuite to its member policies" ;
                    rdfs:domain :TrustPolicySuite ;
                    rdfs:range :TrustPolicy
                    .


# -----------------------------------------------
# Trust Policy
# -----------------------------------------------
#
# A trust policy defines rules for accepting or rejecting RDF statements.
# A policy consists of graph patterns and conditions. Taken together,
# they form an implicit TriQL.P query. A statement is trusted if it matches
# the query. The policy also provides explanations templates which
# can generate an explanation stating why a particular statement was trusted
# (but not why a statement was rejected).

:TrustPolicy        rdf:type rdfs:Class ;
                    rdfs:label "Trust policy" ;
                    rdfs:comment "A TPL trust policy" ;
                    rdfs:subClassOf :ExplainableThing
                    .
:policyName         rdf:type rdf:Property ;
                    rdfs:label "policy name" ;
                    rdfs:comment "A trust policy's name" ;
                    rdfs:domain :TrustPolicy ;
                    rdfs:subPropertyOf rdfs:label
                    .
:policyDescription  rdf:type rdf:Property ;
                    rdfs:label "policy description" ;
                    rdfs:comment "The description of a trust policy" ;
                    rdfs:domain :TrustPolicy ;
                    rdfs:subPropertyOf rdfs:comment
                    .
:graphPattern       rdf:type rdf:Property ;
                    rdfs:label "graph pattern" ;
                    rdfs:comment "A graph pattern which trusted data must match" ;
                    rdfs:domain :TrustPolicy ;
                    rdfs:range :GraphPattern
                    .
:condition          rdf:type rdf:Property ;
                    rdfs:label "condition" ;
                    rdfs:comment "A TriQL.P expression, matching the Expression production, which trusted data must fulfill" ;
                    rdfs:domain :TrustPolicy
                    .


# -----------------------------------------------
# Graph Pattern
# -----------------------------------------------

:GraphPattern       rdf:type rdfs:Class ;
                    rdfs:label "A graph pattern" ;
                    rdfs:comment "A graph pattern with optional explanations" ;
                    rdfs:subClassOf :ExplainableThing
                    .
:pattern            rdf:type rdf:Property ;
                    rdfs:label "pattern" ;
                    rdfs:comment "A TriQL.P expression, matching the Graph Pattern production" ;
                    rdfs:domain :GraphPattern
                    .


# -----------------------------------------------
# Explanation Templates
# -----------------------------------------------
#
# Explanation templates can be assigned to trust policies and graph patterns.
# They provide a textual explanation, or an RDF graph, explaining why a
# particular RDF statement is trusted by the policy.

:textExplanation    rdf:type rdf:Property ;
                    rdfs:label "text explanation" ;
                    rdfs:comment "A template for a textual explanation; might include @@?var@@ placeholders" ;
                    rdfs:domain :ExplainableThing
                    .
:graphExplanation   rdf:type rdf:Property ;
                    rdfs:label "graph explanation" ;
                    rdfs:comment "A TriQL.P expression matching the TriplePattern production which will generate statements for an RDF graph explanation." ;
                    rdfs:domain :ExplainableThing
                    .


# -----------------------------------------------
# Special system-assigned variable nodes that can be used in graph patterns
# -----------------------------------------------
#
# ?GRAPH            rdfs:comment "The name of the graph which contains the statement" .    
#
# ?SUB              rdfs:comment "The subject of the statement" .
#
# ?PRED             rdfs:comment "The predicate of the statement" .
#
# ?OBJ              rdfs:comment "The predicate of the statement" .
#
# ?USER             rdfs:comment "Represents the current user of the system" .


# -----------------------------------------------
# PolicyTrigger
# -----------------------------------------------

# PolicyTriggers are indicators for the application layer
# that a policy can be used for a class or 
# class/property combination.

# We don't implement PolicyTriggers in version 0.1
# Maybe PolicyTriggers are getting replaced by Fresnel RDFpath expressions

#:PolicyTrigger     rdf:type rdfs:Class ;
#                   rdfs:comment "Triple pattern which triggers one ore more trust policies." 
#                   .
#:triggerDescription rdf:type rdf:Property ;
#                   rdfs:domain :PolicyTrigger
#                   . 
#:pattern           rdf:type rdf:Property ;
#                   .
#:policy            rdf:type rdf:Property ;
#                   rdfs:comment """One ore more trust policies, that should be used.
#                                   Maybe have a policy bag or sequence."""
#                   rdfs:domain :PolicyTrigger
#                   .