use strict;
use warnings;
use Filesys::POSIX      ();
use Filesys::POSIX::Mem ();
use Filesys::POSIX::Bits;
use Test::More ( 'tests' => 30 );
use Test::Exception;
use Test::NoWarnings;
{
    my $fs = Filesys::POSIX->new( Filesys::POSIX::Mem->new );
    $fs->umask(022);
    my $fd = $fs->open( 'foo', $O_CREAT, 0600 );
    ok( $fd == 3,                       'Filesys::POSIX->open() for new file returns file descriptor 3 upon first call' );
    ok( $fs->fstat($fd)->file,          'Filesys::POSIX->open() creates regular inode by default with $O_CREAT' );
    ok( $fs->fstat($fd)->perms == 0600, 'Filesys::POSIX->open() handles mode argument appropriately' );
    my $new_fd = $fs->open( 'bar', $O_CREAT );
    ok( $new_fd == 4, 'Filesys::POSIX->open() for second new file returns file descriptor 4' );
    $fs->close($fd);
    ok( $fs->open( 'bar', $O_RDONLY ) == 3, 'Filesys::POSIX->open() reclaims old file descriptors' );
    $fs->close($fd);
    throws_ok {
        $fs->read( $fd, my $buf, 512 );
    }
    qr/^Invalid file descriptor/, 'Filesys::POSIX->read() throws "Invalid file descriptor" exception on closed fd';
    $fs->close($fd);
    $fs->close($new_fd);
}
{
    my $fs = Filesys::POSIX->new( Filesys::POSIX::Mem->new );
    throws_ok {
        my $fd = $fs->open( 'foo', $O_CREAT | $O_WRONLY );
        $fs->read( $fd, my $buf, 0 );
    }
    qr/^Invalid argument/, "Filesys::POSIX->read() throws 'Invalid argument' when reading on write-only fd";
    throws_ok {
        my $fd = $fs->open( 'foo', $O_CREAT | $O_RDONLY );
        $fs->write( $fd, 'foo', 3 );
    }
    qr/^Invalid argument/, "Filesys::POSIX->write() throws 'Invalid argument' when writing on read-only fd";
    throws_ok {
        my $fd = $fs->open( 'foo', $O_CREAT | $O_RDONLY );
        $fs->print( $fd, 'foo' );
    }
    qr/^Invalid argument/, "Filesys::POSIX->print() throws 'Invalid argument' when writing on read-only fd";
    throws_ok {
        my $fd = $fs->open( 'foo', $O_CREAT | $O_RDONLY );
        $fs->printf( $fd, "Foo: %d\n", 1024 );
    }
    qr/^Invalid argument/, "Filesys::POSIX->printf() throws 'Invalid argument' when writing on read-only fd";
    lives_ok {
        my $fd = $fs->open( 'foo', $O_CREAT | $O_WRONLY );
        $fs->print( $fd, "Hello, world\n" );
    }
    "Filesys::POSIX->print() allows writing to writable fds";
    lives_ok {
        my $fd = $fs->open( 'foo', $O_CREAT | $O_WRONLY );
        $fs->printf( $fd, "Hello, world: %d\n", 1024 );
    }
    "Filesys::POSIX->print() allows writing to writable fds";
    my $fd = $fs->open( 'foo', $O_CREAT | $O_WRONLY );
    ok( $fs->fdopen($fd), "Filesys::POSIX->fdopen() returns a raw file handle for an open file descriptor" );
}
{
    my $fs    = Filesys::POSIX->new( Filesys::POSIX::Mem->new );
    my $fd    = $fs->open( 'baz', $O_CREAT, $S_IFDIR );
    my $inode = $fs->fstat($fd);
    ok( $inode->dir, 'Filesys::POSIX->open() allows for creation of directory inodes when passing $S_IFDIR' );
    $fs->close($fd);
}
{
    my $fs = Filesys::POSIX->new( Filesys::POSIX::Mem->new );
    my $fd = $fs->open( 'meow', $O_CREAT | $O_RDWR );
    ok( $fs->tell($fd) == 0, 'Filesys::POSIX->tell() reports position 0 on newly-created files' );
    ok( $fs->write( $fd, 'foo', 3 ) == 3, 'Filesys::POSIX->write() returns 3 for a 3-byte write operation' );
    ok( $fs->tell($fd) == 3, 'Filesys::POSIX->tell() reports offset 3 after first 3-byte write operation' );
    $fs->write( $fd, 'bar', 3 );
    ok( $fs->tell($fd) == 6, 'Filesys::POSIX->tell() reports offset 6 after second 3-byte write operation' );
    ok( $fs->seek( $fd, 0, $SEEK_SET ) == 0, 'Filesys::POSIX->seek() returns 0 when seeking to position 0' );
    ok( $fs->seek( $fd, 3, $SEEK_SET ) == 3, 'Filesys::POSIX->seek() returns 3 when seeking to position 3' );
    ok( $fs->read( $fd, my $buf, 3 ) == 3, 'Filesys::POSIX->read() returns 3 when reading 3 bytes' );
    ok( $fs->tell($fd) == 6, 'Filesys::POSIX->tell() returns 6 after previous read() call' );
    ok( $buf eq 'bar', 'Filesys::POSIX->read() populated read buffer with expected result' );
    ok( $fs->seek( $fd, 9, $SEEK_SET ) == 9, 'Filesys::POSIX->seek() allows seeking beyond file size' );
    ok( $fs->write( $fd, 'baz', 3 ) == 3, 'Filesys::POSIX->write() allows random access writes' );
    ok( $fs->fstat($fd)->{'size'} == 12, 'Filesys::POSIX->write() updated inode size to 12 bytes' );
    ok( $fs->seek( $fd, 0, $SEEK_SET ) == 0, 'Filesys::POSIX->seek() allows seeking to beginning of file' );
    ok( $fs->read( $fd, $buf, 12 ) == 12, 'Filesys::POSIX->read() read expected number of bytes' );
    ok( $buf eq "foobar\x00\x00\x00baz", 'Filesys::POSIX->read() populated buffer with expected results' );
}