import raw ("core/dependencies.lp")
import raw ("core/control-context.lp")
import raw ("core/unit-tests.lp")

InstallationStatus = type variant(NOT_INSTALLED, INSTALLED).

interface(adhoc){
    pre function expectNoErrors:: InstallationStatus {
        case Error  {NOT_INSTALLED}
        case Success {INSTALLED}
    }
}

interface(extern-c){
  libFake = library:: pkgconfig("libxml-2.0").

  include {
    libFake = ["stdio.h", "stdlib.h"]
  }.
}

exec = pre function(comm:: string) {
	result = system(comm):: num.
	
	if (result==0)::InstallationStatus
		 {ad hoc "Success"}
	else     {ad hoc "Error"}
}

start = function:: int; entry {
    context:: goal(artefact(gcc)).
    
    provideGoals()
}

provideGoals = function:: int {
    loop context ("goal") {
        provideArtefact()
    }
}

provideArtefact = function:: int{
        switch (actionEXISTS())::int
        
        case INSTALLED {0}
        
        case NOT_INSTALLED {
            sequence [
                provideDependencies(),
                actionPROVIDE()
            ]
        }
        
        case default {-1}
}

provideDependencies = function::int {
    rule context:: childs(Child)
    case artefact(Item) {
        artefact_depends(Item, Child)
    }
    
    loop context ("childs") {
        provideArtefact()
    }
}

case context:: artefact(subversion) {
    actionEXISTS = function::int {
        context:: expectNoErrors.
        
        exec("svn --version")
    }
    
    actionPROVIDE = function::int {
        context:: expectNoErrors.
        
        exec("sudo apt-get install subversion")
    }
}

actionEXISTS = function::int {
    -1
}

actionPROVIDE = function::int {
    -1
}


//  DRAFT
/*
 flagIsProvided = if(dictProvided(<item>)) {true} else
 dictProvided = dictProvided + <item>
 
expectErrorCode = pre function(x::int){
    if (x==0)::bool {ad hoc "Success"}
	else {ad hoc "Error"}
}
*/