1 files changed, 100 insertions, 0 deletions
diff --git a/lib/Carton/Environment.pm b/lib/Carton/Environment.pm
new file mode 100644
index 0000000..6a58944
--- /dev/null
+++ b/lib/Carton/Environment.pm
@@ -0,0 +1,100 @@
+package Carton::Environment;
+use strict;
+use Carton::CPANfile;
+use Carton::Snapshot;
+use Carton::Error;
+use Carton::Tree;
+use Path::Tiny;
+
+use Class::Tiny {
+    cpanfile => undef,
+    snapshot => sub { $_[0]->_build_snapshot },
+    install_path => sub { $_[0]->_build_install_path },
+    vendor_cache => sub { $_[0]->_build_vendor_cache },
+    tree => sub { $_[0]->_build_tree },
+};
+
+sub _build_snapshot {
+    my $self = shift;
+    Carton::Snapshot->new(path => $self->cpanfile . ".snapshot");
+}
+
+sub _build_install_path {
+    my $self = shift;
+    if ($ENV{PERL_CARTON_PATH}) {
+        return Path::Tiny->new($ENV{PERL_CARTON_PATH});
+    } else {
+        return $self->cpanfile->path->parent->child("local");
+    }
+}
+
+sub _build_vendor_cache {
+    my $self = shift;
+    Path::Tiny->new($self->install_path->dirname . "/vendor/cache");
+}
+
+sub _build_tree {
+    my $self = shift;
+    Carton::Tree->new(cpanfile => $self->cpanfile, snapshot => $self->snapshot);
+}
+
+sub vendor_bin {
+    my $self = shift;
+    $self->vendor_cache->parent->child('bin');
+}
+
+sub build_with {
+    my($class, $cpanfile) = @_;
+
+    $cpanfile = Path::Tiny->new($cpanfile)->absolute;
+    if ($cpanfile->is_file) {
+        return $class->new(cpanfile => Carton::CPANfile->new(path => $cpanfile));
+    } else {
+        Carton::Error::CPANfileNotFound->throw(error => "Can't locate cpanfile: $cpanfile");
+    }
+}
+
+sub build {
+    my($class, $cpanfile_path, $install_path) = @_;
+
+    my $self = $class->new;
+
+    $cpanfile_path &&= Path::Tiny->new($cpanfile_path)->absolute;
+
+    my $cpanfile = $self->locate_cpanfile($cpanfile_path || $ENV{PERL_CARTON_CPANFILE});
+    if ($cpanfile && $cpanfile->is_file) {
+        $self->cpanfile( Carton::CPANfile->new(path => $cpanfile) );
+    } else {
+        Carton::Error::CPANfileNotFound->throw(error => "Can't locate cpanfile: (@{[ $cpanfile_path || 'cpanfile' ]})");
+    }
+
+    $self->install_path( Path::Tiny->new($install_path)->absolute ) if $install_path;
+
+    $self;
+}
+
+sub locate_cpanfile {
+    my($self, $path) = @_;
+
+    if ($path) {
+        return Path::Tiny->new($path)->absolute;
+    }
+
+    my $current  = Path::Tiny->cwd;
+    my $previous = '';
+
+    until ($current eq '/' or $current eq $previous) {
+        # TODO support PERL_CARTON_CPANFILE
+        my $try = $current->child('cpanfile');
+        if ($try->is_file) {
+            return $try->absolute;
+        }
+
+        ($previous, $current) = ($current, $current->parent);
+    }
+
+    return;
+}
+
+1;
+