// Copyright © 2022 Tobias J. Prisching <tobias.prisching@icloud.com> and CONTRIBUTORS
// See https://github.com/TechnikTobi/little_exif#license for licensing details

use std::fs::copy;
use std::fs::remove_file;
use std::path::Path;

extern crate little_exif;
use little_exif::metadata::Metadata;
use little_exif::exif_tag::ExifTag;
use little_exif::ifd::ExifTagGroup;
use little_exif::u8conversion::*;

fn
main()
-> Result<(), std::io::Error>
{

	// Remove old copy and create new one for writing EXIF data to
	remove_file("examples/copy.png")?;
	remove_file("examples/copy.jpg")?;
	copy("examples/image.png", "examples/copy.png")?;
	copy("examples/image.jpg", "examples/copy.jpg")?;

	let png_path = Path::new("examples/copy.png");
	let jpg_path = Path::new("examples/copy.jpg");

	// Create metadata structs & fill them
	let mut png_data = Metadata::new();
	let mut jpg_data = Metadata::new_from_path(&jpg_path).unwrap();
	fill_metadata(&mut png_data);
	fill_metadata(&mut jpg_data);

	// Write the metadata to the copies
	png_data.write_to_file(&png_path)?;
	jpg_data.write_to_file(&jpg_path)?;
	
	// Read in the metadata again & print it
	println!("\nPNG read result:");
	for tag in &Metadata::new_from_path(png_path).unwrap()
	{
		println!("{:?}", tag);
	}

	println!("\nJPG read result:");
	for tag in &Metadata::new_from_path(jpg_path).unwrap()
	{
		println!("{:?}", tag);
	}

	// Explicitly read in the ImageDescription by tag or hex
	let metadata = Metadata::new_from_path(jpg_path).unwrap();
	let image_description_by_tag = metadata.get_tag(&ExifTag::ImageDescription(String::new())).next().unwrap();
	let image_description_by_hex = metadata.get_tag_by_hex(0x010e, None).next().unwrap();

	// Print it as String
	let endian = metadata.get_endian();
	let image_description_string = String::from_u8_vec(
		&image_description_by_tag.value_as_u8_vec(&metadata.get_endian()),
		&endian
	);

	println!("{:?}", image_description_by_hex);
	println!("{}", image_description_string);

	Ok(())
}

fn
fill_metadata
(
	metadata: &mut Metadata
)
{
	// Set the ImageDescription (IFD0) an ISO (ExifIFD) tag as examples
	// as well as two (to little_exif) unknown tags
	// metadata.set_tag(
	metadata.get_ifd_mut(ExifTagGroup::GENERIC, 0).set_tag(
		ExifTag::UnknownSTRING("test1".to_string(), 0x010d, ExifTagGroup::GENERIC)
	);

	metadata.set_tag(
		ExifTag::ImageDescription("-w 1000 -h 1000 --x_mid=0 --y_mid=0 -z 0.5 -i 1000 -c 8".to_string())
	);

	metadata.set_tag(
		ExifTag::ISO(vec![2022])
	);

	metadata.set_tag(
		ExifTag::UnknownSTRING("test2".to_string(), 0x010c, ExifTagGroup::GENERIC)
	);

	metadata.set_tag(
		ExifTag::FNumber(vec![1.4.into()])
	)
}