#  (C) Copyright David Abrahams 2002. Permission to copy, use, modify, sell and
#  distribute this software is granted provided this copyright notice appears in
#  all copies. This software is provided "as is" without express or implied
#  warranty, and with no claim as to its suitability for any purpose.

import sequence ;
import set ;
import regex ;
import feature ;
import property ;
import numbers ;
import container ;
import "class" : new ;
import string ;

# Transform property-set by applying f to each component property.
local rule apply-to-property-set ( f property-set )
{
    local properties = [ feature.split $(property-set) ] ;
    return [ string.join [ $(f) $(properties) ] : / ] ;
}

# expand the given build request by combining all property-sets which don't
# specify conflicting non-free features.
rule expand-no-defaults ( property-sets * )
{
    # First make all features and subfeatures explicit
    local expanded-property-sets = [ 
      sequence.transform apply-to-property-set feature.expand-subfeatures
        : $(property-sets) ] ;
    
    # Now combine all of the expanded property-sets
    local product = [ x-product $(expanded-property-sets) : $(feature-space) ] ;
    
    return $(product) ;
}

# implementaiton of x-product, below
local rule x-product-aux ( property-sets + )
{
    local result ;
    local p = [ feature.split $(property-sets[1]) ] ;
    local f = [ set.difference $(p:G) : [ feature.free-features ] ] ;
    local seen ;
    # No conflict with things used at a higher level?
    if ! [ set.intersection $(f) : $(x-product-used) ]
    {
        local x-product-seen ;
        {
            # don't mix in any conflicting features
            local x-product-used = $(x-product-used) $(f) ;
            
            if $(property-sets[2])
            {
                local rest = [ x-product-aux $(property-sets[2-]) : $(feature-space) ] ;
                result = $(property-sets[1])/$(rest) ;
            }
            
            result ?= $(property-sets[1]) ;
        }
        
        # If we didn't encounter a conflicting feature lower down,
        # don't recurse again.
        if ! [ set.intersection $(f) : $(x-product-seen) ]
        {
            property-sets = ;
        }
        
        seen = $(x-product-seen) ;
    }
    
    if $(property-sets[2])
    {
        result += [ x-product-aux $(property-sets[2-]) : $(feature-space) ] ;
    }
    
    # Note that we've seen these features so that higher levels will
    # recurse again without them set.
    x-product-seen += $(f) $(seen) ;
    return $(result) ;
}

# Return the cross-product of all elements of property-sets, less any
# that would contain conflicting values for single-valued features.
local rule x-product ( property-sets * )
{
    if $(property-sets).non-empty
    {
        # prepare some "scoped globals" that can be used by the
        # implementation function, x-product-aux.
        local x-product-seen x-product-used ;
        return [ x-product-aux $(property-sets) : $(feature-space) ] ;
    }
    # otherwise return empty
}

# 
# Returns the result of 'expand-no-defaults' after appying feature default to it.
#
rule expand ( property-sets * )
{
    local expanded = [ expand-no-defaults $(property-sets) : $(feature-space) ] ;
    
    expanded ?= "" ;
    
    local result ;
    for local p in $(expanded) 
    {
        p = [ feature.split $(p) ] ;
        
        if ! $(p)
        {
            p = ;
        }
        
        p = [ feature.add-defaults $(p) ] ;
        result += $(p:J=/) ;
    }
    return $(result) ;
}

# Returns true if 'v' is either implicit value, or
# the part before the first '-' symbol is implicit value
local rule looks-like-implicit-value ( v )
{
    
    if [ feature.is-implicit-value $(v) ]
    {
        return true ;
    }
    else
    {
        local split = [ regex.split $(v) - ] ;
        if [ feature.is-implicit-value $(split[1]) ]
        {
            return true ;
        }        
    }
}


# Takes the command line tokens (such as taken from ARGV rule) and constructs
# build request from it.
# Returns a vector of two vectors (where "vector" means container.jam's "vector"). 
# First is the set of targets specified in the command line, and second is
# the set of requested build properties. 
rule from-command-line ( command-line * )
{
    local targets ;
    local properties ;

    command-line = $(command-line[2-]) ;
    for local e in $(command-line)
    {
        if ! [ MATCH "^(-).*" : $(e) ] 
        {
            # Build request spec either has "=" in it, or completely
            # consists of implicit feature values.
            local fs = feature-space ;
            if [ MATCH "(.*=.*)" : $(e) ] 
               || [ looks-like-implicit-value $(e:D=) : $(feature-space) ] 
            {
                properties += [ convert-command-line-element $(e) : $(feature-space) ] ;
            }
            else
            {
                targets += $(e) ;
            }
        }
    }
    return [ new vector [ new vector $(targets) ] [ new vector $(properties) ] ] ;
}

# Converts one element of command line build request specification into
# internal form.
local rule convert-command-line-element ( e )
{
    local result ;
    local parts = [ regex.split $(e) "/" ] ;
    for local p in $(parts) 
    {
        local m = [ MATCH "([^=]*)=(.*)" : $(p) ] ;
        local lresult ;
        if $(m) 
        {
            local feature = $(m[1]) ;
            local values = [ regex.split $(m[2]) "," ] ;            
            lresult = <$(feature)>$(values) ;            
        }
        else
        {
            lresult = [ regex.split $(p) "," ] ;
        }

        if ! [ MATCH (.*-.*) : $(p) ]
        {          
            # property.validate cannot handle subfeatures,
            # so we avoid the check here.
            for local p in $(lresult)
            {
                property.validate $(p) : $(feature-space) ;
            }
        }
        

        if ! $(result) 
        {
            result = $(lresult) ;
        }
        else
        {
            result = $(result)/$(lresult) ;
        }
    }  
    
    return $(result) ;
}

rule __test__ ( )
{
    import assert feature ;
    
    feature.prepare-test build-request-test-temp ;
    
    import build-request ;
    import build-request : expand-no-defaults : build-request.expand-no-defaults ;
    import errors : try catch ;
    import feature : feature subfeature ;

    feature toolset : gcc msvc borland : implicit ;
    subfeature toolset gcc : version : 2.95.2 2.95.3 2.95.4
      3.0 3.0.1 3.0.2 : optional ;

    feature variant : debug release : implicit composite ;
    feature inlining : on off ;
    feature "include" : : free ;

    feature stdlib : native stlport : implicit ;

    feature runtime-link : dynamic static : symmetric ;

    # empty build requests should expand to empty.
    assert.result
      : build-request.expand-no-defaults
      ;

    assert.result <toolset>gcc/<variant>debug/<inlining>on/<stdlib>native/<runtime-link>dynamic
      : build-request.expand
      ;

    assert.result
      <toolset>gcc/<toolset-gcc:version>3.0.1/<stdlib>stlport/<variant>debug
      <toolset>msvc/<stdlib>stlport/<variant>debug
      <toolset>msvc/<variant>debug 

      : build-request.expand-no-defaults gcc-3.0.1/stlport msvc/stlport msvc debug
      ;

    assert.result
      <toolset>gcc/<toolset-gcc:version>3.0.1/<stdlib>stlport/<variant>debug/<inlining>on/<runtime-link>dynamic
      <toolset>msvc/<stdlib>stlport/<variant>debug/<inlining>on/<runtime-link>dynamic
      <toolset>msvc/<variant>debug/<inlining>on/<stdlib>native/<runtime-link>dynamic

      : build-request.expand gcc-3.0.1/stlport msvc/stlport msvc debug
      ;

    assert.result
      <toolset>gcc/<toolset-gcc:version>3.0.1/<stdlib>stlport/<variant>debug
      <toolset>msvc/<variant>debug 
      <variant>debug/<toolset>msvc/<stdlib>stlport

      : build-request.expand-no-defaults gcc-3.0.1/stlport msvc debug msvc/stlport
      ;

    assert.result
      <toolset>gcc/<toolset-gcc:version>3.0.1/<stdlib>stlport/<variant>debug/<inlining>off
      <toolset>gcc/<toolset-gcc:version>3.0.1/<stdlib>stlport/<variant>release/<inlining>off

      : build-request.expand-no-defaults gcc-3.0.1/stlport debug release <inlining>off
      ;        

    assert.result
      <include>a/b/c/<toolset>gcc/<toolset-gcc:version>3.0.1/<stdlib>stlport/<variant>debug/<include>x/y/z
      <include>a/b/c/<toolset>msvc/<stdlib>stlport/<variant>debug/<include>x/y/z
      <include>a/b/c/<toolset>msvc/<variant>debug/<include>x/y/z 

      : build-request.expand-no-defaults <include>a/b/c gcc-3.0.1/stlport msvc/stlport msvc debug  <include>x/y/z
      ;

    local r ;

    r = [ build-request.from-command-line bjam debug runtime-link=dynamic ] ;              
    assert.equal [ $(r).get-at 1 ] : ;
    assert.equal [ $(r).get-at 2 ] : debug <runtime-link>dynamic ;

    try ;
    {

        build-request.from-command-line bjam gcc/debug runtime-link=dynamic/static ;
    }
    catch \"static\" is not a value of an implicit feature ;


    r = [ build-request.from-command-line bjam -d2 --debug debug target runtime-link=dynamic ] ;
    assert.equal [ $(r).get-at 1 ] : target ;
    assert.equal [ $(r).get-at 2 ] : debug <runtime-link>dynamic ;

    r = [ build-request.from-command-line bjam debug runtime-link=dynamic,static ] ;
    assert.equal [ $(r).get-at 1 ] : ;
    assert.equal [ $(r).get-at 2 ] : debug <runtime-link>dynamic <runtime-link>static ;

    r = [ build-request.from-command-line bjam debug gcc/runtime-link=dynamic,static ] ;
    assert.equal [ $(r).get-at 1 ] : ;
    assert.equal [ $(r).get-at 2 ] : debug gcc/<runtime-link>dynamic 
                 gcc/<runtime-link>static ;

    r = [ build-request.from-command-line bjam msvc gcc,borland/runtime-link=static ] ;
    assert.equal [ $(r).get-at 1 ] : ;
    assert.equal [ $(r).get-at 2 ] : msvc gcc/<runtime-link>static 
                    borland/<runtime-link>static ;

    r = [ build-request.from-command-line bjam gcc-3.0 ] ;
    assert.equal [ $(r).get-at 1 ] : ;
    assert.equal [ $(r).get-at 2 ] : gcc-3.0 ;

    feature.finish-test build-request-test-temp ;
}