=pod

=encoding utf-8

=head1 NAME

Spreadsheet::XLSX::Reader::LibXML::Worksheet - Read xlsx worksheets with LibXML

=head1 SYNOPSIS

See the SYNOPSIS in the L<Workbook class|Spreadsheet::XLSX::Reader::LibXML/SYNOPSIS>

=head1 DESCRIPTION

If you want just learn the key elements of how to use the Worksheet instances returned 
from L<Spreadsheet::XLSX::Reader::LibXML> this POD is for you.  I<You will also want to 
skip the next paragraph.>  First, it is best to generate a worksheet instance with the 
main class.  Once you have done that there are several ways to step through the data and 
return information from the identified location.

As you may have noticed this is only the pod explaining the Worksheet class not the file 
containing the actual class.  In fact worksheets are built somwhat on the fly with an 
amalgam of classes, roles, and traits each with their own code and POD.  Since this is a 
L<Moose> package I tried to architect it as extensibly as possible.  For protips to 
manipulate each element of the package look at the pod for that element and then review the 
tests for that element.  Every .pm file has it's own test.  I<I use 
L<MooseX::ShortCut::BuildInstance> in order to test just the role or class functionality>.  
The file t/Spreadsheet/XLSX/Reader/LibXML/10-get_cell.t represents a good 'under the hood' 
look at the way each is integrated into this larger package since it doesn't use the top 
level class for the test.  The one exception to full extensibility is the worksheet class 
itself.  Because worksheet reading is central to the functionality of this package the core 
worksheet build is hard coded.

=head2 The way to set what type of information is returned

There is a an attribute set in the primary instance called 
L<group_return_type|Spreadsheet::XLSX::Reader::LibXML/group_return_type>.  Setting 
this attribute will return either a full L<Spreadsheet::XLSX::Reader::LibXML::Cell> instance, 
just the unformatted value, or the formatted value.  For more details on the data available 
in the Cell instance read the documentation for the 
L<Cell|Spreadsheet::XLSX::Reader::LibXML::Cell> instance.

=head2 Methods to access data from the sheet

These are the various functions that are available (independent of sheet parser type) to 
select which cells to read.

=head3 get_cell( $row, $column )

=over

B<Definition:> Indicate both the requested row and requested column and the information for 
that position will be returned.  Both $row and $column are required

B<Accepts:> the list ( $row, $column ) both required

B<Returns:> see L<returns|/The way to set what type of information is returned> for details 
on what is returned

=back

=head3 get_next_value

=over

B<Definition:> Reading left to right and top to bottom this will return the next cell with 
a value.  This actually includes cells with no value but some unique formatting such as 
cells that have been merged with other cells.

B<Accepts:> nothing

B<Returns:> see L<returns|/The way to set what type of information is returned> for details 
on what is returned

=back

=head3 fetchrow_arrayref( $row )

=over

B<Definition:> In an homage to L<DBI> I included this function to return an array ref of 
the cells or values in the requested $row.  If no row is requested this returns the 'next' 
row.  In the array ref any empty and non unique cell will show as 'undef'.

B<Accepts:> undef = next|$row = a row integer indicating the desired row

B<Returns:> an array ref of all possible column positions in that row with data filled in 
as appropriate.

=back

=head3 fetchrow_array( $row )

=over

B<Definition:> This function is just like L<fetchrow_arrayref|/fetchrow_arrayref( $row )> 
except it returns an array instead of an array ref

B<Accepts:> undef = next|$row = a row integer indicating the desired row

B<Returns:> an array of all possible column positions in that row with data filled in 
as appropriate.

=back

=head3 set_headers( @header_row_list )

=over

B<Definition:> This function is used to set headers used in the function 
L<fetchrow_hashref|/fetchrow_hashref( $row )>.  It accepts a list of row numbers that 
will be collated into a set of headers used to build the hashref for each row.
The header rows are coallated in sequence with the first number taking precedence.  
The list is also used to set the lowest row of the headers in the table.  All rows 
at that level and higher will be considered out of the table and will return undef 
while setting the error instance.  If some of the columns do not have values then 
the instance will auto generate unique headers for each empty header column to fill 
out the header ref.

B<Accepts:> a list of row numbers

B<Returns:> an array ref of the built headers for review

=back

=head3 fetchrow_hashref( $row )

=over

B<Definition:> This function is used to return a hashref representing the data in the 
specified row.  If no $row value is passed it will return the 'next' row of data.  A call 
to this function without L<setting|/set_headers( @header_row_list )> the headers first 
will return undef and set the error instance.

B<Accepts:> a target $row number for return values or undef meaning 'next'

B<Returns:> a hash ref of the values for that row

=back

=head3 min_row

=over

B<Definition:> This is the minimum row with data listed in the sheet.  This value 
is affected by the workbook attributes 
L<from_the_edge|Spreadsheet::XLSX::Reader::LibXML/from_the_edge>, and 
L<count_from_zero|Spreadsheet::XLSX::Reader::LibXML/count_from_zero>

B<Accepts:> nothing

B<Returns:> an integer

=back

=head3 has_min_row

=over

B<Definition:> The L<predicate|Moose::Manual::Attributes/Predicate and clearer methods> 
of min_row

=back

=head3 max_row

=over

B<Definition:> This is the maximum row with data listed in the sheet.  This value 
is affected by the workbook attribute 
L<count_from_zero|Spreadsheet::XLSX::Reader::LibXML/count_from_zero>

B<Accepts:> nothing

B<Returns:> an integer

=back

=head3 has_max_row

=over

B<Definition:> The L<predicate|Moose::Manual::Attributes/Predicate and clearer methods> 
of max_row

=back

=head3 min_col

=over

B<Definition:> This is the minimum column with data listed in the sheet.  This value 
is affected by the workbook attributes 
L<from_the_edge|Spreadsheet::XLSX::Reader::LibXML/from_the_edge>, and 
L<count_from_zero|Spreadsheet::XLSX::Reader::LibXML/count_from_zero>

B<Accepts:> nothing

B<Returns:> an integer

=back

=head3 has_min_col

=over

B<Definition:> The L<predicate|Moose::Manual::Attributes/Predicate and clearer methods> 
of min_col

=back

=head3 max_col

=over

B<Definition:> This is the maximum row with data listed in the sheet.  This value 
is affected by the workbook attribute 
L<count_from_zero|Spreadsheet::XLSX::Reader::LibXML/count_from_zero>

B<Accepts:> nothing

B<Returns:> an integer

=back

=head3 has_max_col

=over

B<Definition:> The L<predicate|Moose::Manual::Attributes/Predicate and clearer methods> 
of max_col

=back

=head3 row_range

=over

B<Definition:> This returns a list with the minimum row followed by the 
maximum row.  This list is affected by the workbook attributes 
L<from_the_edge|Spreadsheet::XLSX::Reader::LibXML/from_the_edge>, and 
L<count_from_zero|Spreadsheet::XLSX::Reader::LibXML/count_from_zero>

B<Accepts:> nothing

B<Returns:> ( $minimum_row, $maximum_row ) - integers

=back

=head3 col_range

=over

B<Definition:> This returns a list with the minimum column followed by the 
maximum column.  This list is affected by the workbook attributes 
L<from_the_edge|Spreadsheet::XLSX::Reader::LibXML/from_the_edge>, and 
L<count_from_zero|Spreadsheet::XLSX::Reader::LibXML/count_from_zero>

B<Accepts:> nothing

B<Returns:> ( $minimum_column, $maximum_column ) - integers

=back

=head2 Attributes

These are attributes that affect the behaviour of the returned data in the worksheet 
instance.  In general you would not set these on instance generation, I<Because the primary 
class will generate this instance for you>.  Rather you would use the attribue methods 
listed with each attribute to change the attribute after the worksheet instance has been 
generated.  Additionally at the end of this list you will see a link to the workbook 
instance itself for access to all those settings as well.

=head3 min_header_col

=over

B<Definition:> This attribute affects the hashref that is returned in the method 
L<fetchrow_hashref|/fetchrow_hashref( $row )>.  If the table you are reading does not 
start in the first column of the sheet then you need to indicate where to start.  
Otherwize the fetchrow_hashref method will return auto generated headers and attach 
them to the cell data outside your table but inside the sheet data boundaries.  This 
attribute tells fetchrow_hashref what column to use to start the hash ref build.

B<Default:> undef (which is equivalent to the minimum column of the sheet)

B<Range:> The minimum column of the sheet to or less than the
L<max_header_col|/max_header_col>

B<attribute methods> Methods provided to adjust this attribute

=over

B<get_min_header_col>

=over

B<Definition:> returns the value stored in the attribute

=back

B<set_min_header_col>

=over

B<Definition:> Sets a new value for the attribute

=back

B<has_min_header_col>

=over

B<Definition:> Indicates if the attribute has a stored value

=back

=back

=back

=head3 max_header_col

=over

B<Definition:> This attribute affects the hashref that is returned in the method 
L<fetchrow_hashref|/fetchrow_hashref( $row )>.  If the table you are reading ends 
before the max column of the sheet then you need indicate where to stop reading.  
Otherwize the fetchrow_hashref method will return auto generated headers and attach 
them to the cell values outside your table.  This attribute tells fetchrow_hashref 
what column to use to end the hash ref build.

B<Default:> undef (equal to the maximum column of the sheet)

B<Range:> The maximum column of the sheet to or less than the 
L<min_header_col|/min_header_col>

B<attribute methods> Methods provided to adjust this attribute

=over

B<get_max_header_col>

=over

B<Definition:> returns the value stored in the attribute

=back

B<set_max_header_col>

=over

B<Definition:> Sets a new value for the attribute

=back

B<has_max_header_col>

=over

B<Definition:> Indicates if the attribute has a stored value

=back

=back

=back

=head3 custom_formats

=over

B<Definition:> This package will generate value conversions that generally 
match the numerical conversions set in the Excel spreadsheet.  However, it 
may be that you want to convert the unformatted values for certain cells, 
rows, or columns in some user defined way.  Build an object instance that 
has the two following methods; 'assert_coerce' and 'display_name'.  Then 
place it here in this attribute as a value to a hash key that is keyed on 
the target Cell ID, or the row number, or the Column letter callout and 
this package will assign that conversion when calling 'value' on the cell 
rather than the conversion stored in the Excel spreadsheet.

B<Default:> {} = no custom conversions

B<Range:> keys representing cell ID's, row numbers, or column letter callouts


B<Example:>

Building a converter on the fly (or use L<Type::Library> or L<MooseX::Types>)

	use DateTimeX::Format::Excel;
	use DateTime::Format::Flexible;
	use Type::Coercion;
	use Type::Tiny;
	my	@args_list	= ( system_type => 'apple_excel' );
	my	$converter	= DateTimeX::Format::Excel->new( @args_list );
	my	$string_via	= sub{ 
							my	$str = $_[0];
							return DateTime::Format::Flexible->parse_datetime( $str );#my	$dt	= 
							#~ return $dt->format_cldr( 'yyyy-M-d' );
						};
	my	$num_via	= sub{
							my	$num = $_[0];
							return $converter->parse_datetime( $num );#my	$dt = 
							#~ return $dt->format_cldr( 'yyyy-M-d' );
						};
	
	# Turn date strings or Excel date numbers to DateTime objects!
	my	$date_time_from_value = Type::Coercion->new( 
		type_coercion_map => [ Num, $num_via, Str, $string_via, ],
	);
	$date_time_type = Type::Tiny->new(
			name		=> 'Custom_date_type',
			constraint	=> sub{ ref($_) eq 'DateTime' },
			coercion	=> $date_time_from_value,
		);
	
	# Deep coercion! to handle first the $date_time_from_value coercion and then 
	#    build a specific date string output
	$string_type = Type::Tiny->new(
			name		=> 'YYYYMMDD',
			constraint	=> sub{
				!$_ or (
				$_ =~ /^\d{4}\-(\d{2})-(\d{2})$/ and
				$1 > 0 and $1 < 13 and $2 > 0 and $2 < 32 )
			},
			coercion	=> Type::Coercion->new(
				type_coercion_map =>[
					$date_time_type->coercibles, sub{ my $tmp = $date_time_type->coerce( $_ ); $tmp->format_cldr( 'yyyy-MM-dd' ) },
				],
			),
	);

Setting custom conversions to use for the worksheet

	my $worksheet = $workbook->worksheet( 'TargetWorksheetName' );
	$worksheet->set_custom_formats( {
		E10	=> $date_time_type,
		10	=> $string_type,
		D14	=> $string_type,
	} );

B<attribute methods> Methods provided to adjust this attribute

=over

B<set_custom_formats>

=over

B<Definition:> Sets a new (complete) hashref for the attribute

=back

B<has_custom_format( $key )>

=over

B<Definition:> checks if the specific custom format $key is set

=back

B<set_custom_format( $key => $coercion, ... )>

=over

B<Definition:> sets the specific custom format $key(s) with $coercion(s)

=back

B<get_custom_format( $key )>

=over

B<Definition:> returns the specific custom format for that $key (see has_custom_format )

=back

=back

=back

=head3 sheet_rel_id

=over

B<Definition:> This is the relId of the sheet listed in the XML of the .xlsx file.  
You probably don't care and you should never set this value.

B<attribute methods> Methods provided to adjust this attribute

=over

B<rel_id>

=over

B<Definition:> returns the value stored in the attribute

=back

=back

=back

=head3 sheet_id

=over

B<Definition:> This is the Id of the sheet listed in the XML of the .xlsx file.  
You probably don't care and you should never set this value.

B<attribute methods> Methods provided to adjust this attribute

=over

B<sheet_id>

=over

B<Definition:> returns the value stored in the attribute

=back

=back

=back

=head3 sheet_position

=over

B<Definition:> This is the visual sheet position in the .xlsx file.  
You should never set this value.

B<attribute methods> Methods provided to adjust this attribute

=over

B<position>

=over

B<Definition:> returns the value stored in the attribute

=back

=back

=back

=head3 sheet_name

=over

B<Definition:> This is the visual sheet name in the .xlsx file.  
You should never set this value.

B<attribute methods> Methods provided to adjust this attribute

=over

B<get_name>

=over

B<Definition:> returns the value stored in the attribute

=back

=back

=back

=head3 workbook_instance

=over

B<Definition:> This attribute holds a reference back to the workbook instance 
so that the worksheet has access to the global settings managed there.  
As a consequence some of the same methods available to the workbook are 
available here in the worksheet.  I<Beware that setting or adjusting 
the workbook level attributes with methods here will be universal and 
affect other worksheets.>  If that doesn't make sence then don't use 
these methods.  (Nothing to see here! Move along.)

B<Default:> a Spreadsheet::XLSX::Reader::LibXML instance

B<attribute methods> Methods of the workbook exposed here by the 
L<delegation|Moose::Manual::Attributes/Delegation> of the instance to 
this class through this attribute

=over

B<counting_from_zero>

=over

B<Definition:> returns the 
<count_from_zero|Spreadsheet::XLSX::Reader::LibXML/count_from_zero> 
state

=back

B<boundary_flag_setting>

=over

B<Definition:> returns the 
<file_boundary_flags|Spreadsheet::XLSX::Reader::LibXML/file_boundary_flags> 
state

=back

B<change_boundary_flag( $Bool )>

=over

B<Definition:> sets the 
<file_boundary_flags|Spreadsheet::XLSX::Reader::LibXML/file_boundary_flags> 
state (B<For the whole workbook!>)

=back

B<get_shared_string_position( $int )>

=over

B<Definition:> returns the shared string data stored in the sharedStrings 
file at position $int.  For more information review 
L<Spreadsheet::XLSX::Reader::LibXML::SharedStrings>.  I<This is a delegation 
of a delegation!>

=back

B<get_format_position( $int, [$header] )>

=over

B<Definition:> returns the format data stored in the styles 
file at position $int.  If the optional $header is passed only the data for that 
header is returned.  Otherwise all styles for that position are returned.  
For more information review 
L<Spreadsheet::XLSX::Reader::LibXML::Styles>.  I<This is a delegation 
of a delegation!>

=back

B<set_empty_is_end( $Bool )>

=over

B<Definition:> sets the 
<empty_is_end|Spreadsheet::XLSX::Reader::LibXML/empty_is_end> 
state (B<For the whole workbook!>)

=back

B<is_empty_the_end>

=over

B<Definition:> returns the workbook state for the attribute
<empty_is_end|Spreadsheet::XLSX::Reader::LibXML/empty_is_end> 

=back

B<get_group_return_type>

=over

B<Definition:> returns the workbook state for the attribute
<group_return_type|Spreadsheet::XLSX::Reader::LibXML/group_return_type> 

=back

B<set_group_return_type( (instance|unformatted|value) )>

=over

B<Definition:> sets the 
<group_return_type|Spreadsheet::XLSX::Reader::LibXML/group_return_type> 
state (B<For the whole workbook!>)

=back

B<get_epoch_year>

=over

B<Definition:> returns the workbook state for the attribute
<epoch_year|Spreadsheet::XLSX::Reader::LibXML/epoch_year> collected from 
the L<Spreadsheet::XLSX::Reader::LibXML::Styles> class.

=back

B<change_output_encoding>

=over

B<Definition:> This is a L<delegated|Moose::Manual::Delegation> method from 
the L<styles|Spreadsheet::XLSX::Reader::LibXML::Styles> class (stored as a 
private instance in the workbook).  It is held (and documented) in the 
L<Spreadsheet::XLSX::Reader::LibXML::FmtDefault> role.  It (L<potentially
|Spreadsheet::XLSX::Reader::LibXML::FmtDefault/change_output_encoding( $string )>
) can process a string to a new output encoding.

=back

B<get_date_behavior>

=over

B<Definition:> This is a L<delegated|Moose::Manual::Delegation> method from 
the L<styles|Spreadsheet::XLSX::Reader::LibXML::Styles> class (stored as a 
private instance in the workbook).  It is held (and documented) in the 
L<Spreadsheet::XLSX::Reader::LibXML::ParseExcelFormatStrings> role.  It will 
indicate how far unformatted L<transformation
|Spreadsheet::XLSX::Reader::LibXML::ParseExcelFormatStrings/datetime_dates> 
is carried for date coercions. 

=back

B<set_date_behavior>

=over

B<Definition:> This is a L<delegated|Moose::Manual::Delegation> method from 
the L<styles|Spreadsheet::XLSX::Reader::LibXML::Styles> class (stored as a 
private instance in the workbook).  It is held (and documented) in the 
L<Spreadsheet::XLSX::Reader::LibXML::ParseExcelFormatStrings> role.  It will 
set how far unformatted L<transformation
|Spreadsheet::XLSX::Reader::LibXML::ParseExcelFormatStrings/datetime_dates> 
is carried for date coercions. 

=back

=back

=back

=head1 SUPPORT

=over

L<github Spreadsheet::XLSX::Reader::LibXML/issues|https://github.com/jandrew/Spreadsheet-XLSX-Reader-LibXML/issues>

=back

=head1 TODO

=over

B<1.> Add a way to set manual headers for fetchrow_hashref

B<2.> Add a pivot table reader (sometimes returns different values than just the sheet shows)

B<3.> Add more exposure to worksheet formatting values

B<4.> Add a DOM version of the parser

=back

=head1 AUTHOR

=over

=item Jed Lund

=item jandrew@cpan.org

=back

=head1 COPYRIGHT

This program is free software; you can redistribute
it and/or modify it under the same terms as Perl itself.

The full text of the license can be found in the
LICENSE file included with this module.

This software is copyrighted (c) 2014 by Jed Lund

=head1 DEPENDENCIES

=over

L<Spreadsheet::XLSX::Reader::LibXML>

=back

=head1 SEE ALSO

=over

L<Spreadsheet::ParseExcel> - Excel 2003 and earlier

L<Spreadsheet::XLSX> - 2007+

L<Spreadsheet::ParseXLSX> - 2007+

L<Log::Shiras|https://github.com/jandrew/Log-Shiras>

=over

All lines in this package that use Log::Shiras are commented out

=back

=back

=cut

#########1#########2 main pod documentation end  5#########6#########7#########8#########9