use std::{io::Read,path::PathBuf};
use clap::{Args,Parser,Subcommand};
use anyhow::Result as AResult;
use futures::StreamExt;
use rbx_asset::context::{RobloxContext,InventoryItem,AssetVersion};

type AssetID=u64;
type AssetIDFileMap=Vec<(AssetID,PathBuf)>;
const CONCURRENT_DECODE:usize=8;
const CONCURRENT_REQUESTS:usize=32;

#[derive(Parser)]
#[command(author,version,about,long_about=None)]
#[command(propagate_version = true)]
struct Cli{
	#[command(subcommand)]
	command:Commands,
}

#[derive(Subcommand)]
enum Commands{
	DownloadHistory(DownloadHistorySubcommand),
	Download(DownloadSubcommand),
	DownloadDecompile(DownloadDecompileSubcommand),
	DownloadGroupInventoryJson(DownloadGroupInventoryJsonSubcommand),
	Create(CreateSubcommand),
	Upload(UploadSubcommand),
	Compile(CompileSubcommand),
	CompileUpload(CompileUploadSubcommand),
	Decompile(DecompileSubcommand),
	DecompileHistoryIntoGit(DecompileHistoryIntoGitSubcommand),
	DownloadAndDecompileHistoryIntoGit(DownloadAndDecompileHistoryIntoGitSubcommand),
}

#[derive(Args)]
struct DownloadHistorySubcommand{
	#[arg(long)]
	asset_id:AssetID,
	#[arg(long)]
	cookie_type:CookieType,
	#[arg(long)]
	cookie:String,
	#[arg(long)]
	output_folder:Option<PathBuf>,
	#[arg(long)]
	continue_from_versions:Option<bool>,
	#[arg(long)]
	start_version:Option<u64>,
	#[arg(long)]
	end_version:Option<u64>,
}
#[derive(Args)]
struct DownloadSubcommand{
	#[arg(long)]
	cookie_type:CookieType,
	#[arg(long)]
	cookie:String,
	#[arg(long)]
	output_folder:Option<PathBuf>,
	#[arg(required=true)]
	asset_ids:Vec<AssetID>,
}
#[derive(Args)]
struct DownloadGroupInventoryJsonSubcommand{
	#[arg(long)]
	cookie_type:CookieType,
	#[arg(long)]
	cookie:String,
	#[arg(long)]
	output_folder:Option<PathBuf>,
	#[arg(long)]
	group:u64,
}
#[derive(Args)]
struct CreateSubcommand{
	#[arg(long)]
	cookie_type:CookieType,
	#[arg(long)]
	cookie:String,
	#[arg(long)]
	model_name:String,
	#[arg(long)]
	description:Option<String>,
	#[arg(long)]
	input_file:PathBuf,
	#[arg(long)]
	group:Option<u64>,
	#[arg(long)]
	free_model:Option<bool>,
	#[arg(long)]
	allow_comments:Option<bool>,
}
#[derive(Args)]
struct UploadSubcommand{
	#[arg(long)]
	asset_id:AssetID,
	#[arg(long)]
	cookie_type:CookieType,
	#[arg(long)]
	cookie:String,
	#[arg(long)]
	input_file:PathBuf,
	#[arg(long)]
	group:Option<u64>,
}
#[derive(Args)]
struct CompileSubcommand{
	#[arg(long)]
	input_folder:Option<PathBuf>,
	#[arg(long)]
	output_file:PathBuf,
	#[arg(long)]
	style:Option<Style>,
	#[arg(long)]
	template:Option<PathBuf>,
}
#[derive(Args)]
struct CompileUploadSubcommand{
	#[arg(long)]
	asset_id:AssetID,
	#[arg(long)]
	cookie_type:CookieType,
	#[arg(long)]
	cookie:String,
	#[arg(long)]
	input_file:PathBuf,
	#[arg(long)]
	group:Option<u64>,
	#[arg(long)]
	input_folder:Option<PathBuf>,
	#[arg(long)]
	style:Option<Style>,
	#[arg(long)]
	template:Option<PathBuf>,
}
#[derive(Args)]
struct DecompileSubcommand{
	#[arg(long)]
	input_file:PathBuf,
	#[arg(long)]
	output_folder:Option<PathBuf>,
	#[arg(long)]
	style:Style,
	#[arg(long)]
	write_template:Option<bool>,
	#[arg(long)]
	write_models:Option<bool>,
	#[arg(long)]
	write_scripts:Option<bool>,
}
#[derive(Args)]
struct DownloadDecompileSubcommand{
	#[arg(long)]
	cookie_type:CookieType,
	#[arg(long)]
	cookie:String,
	#[arg(long)]
	output_folder:Option<PathBuf>,
	#[arg(long)]
	asset_id:AssetID,
	#[arg(long)]
	style:Style,
	#[arg(long)]
	write_template:Option<bool>,
	#[arg(long)]
	write_models:Option<bool>,
	#[arg(long)]
	write_scripts:Option<bool>,
}
#[derive(Args)]
struct DecompileHistoryIntoGitSubcommand{
	#[arg(long)]
	input_folder:PathBuf,
	//currently output folder must be the current folder due to git2 limitations
	//output_folder:cli.output.unwrap(),
	#[arg(long)]
	style:Style,
	#[arg(long)]
	git_committer_name:String,
	#[arg(long)]
	git_committer_email:String,
	#[arg(long)]
	write_template:Option<bool>,
	#[arg(long)]
	write_models:Option<bool>,
	#[arg(long)]
	write_scripts:Option<bool>,
}
#[derive(Args)]
struct DownloadAndDecompileHistoryIntoGitSubcommand{
	#[arg(long)]
	asset_id:AssetID,
	#[arg(long)]
	cookie_type:CookieType,
	#[arg(long)]
	cookie:String,
	//currently output folder must be the current folder due to git2 limitations
	//output_folder:cli.output.unwrap(),
	#[arg(long)]
	style:Style,
	#[arg(long)]
	git_committer_name:String,
	#[arg(long)]
	git_committer_email:String,
	#[arg(long)]
	write_template:Option<bool>,
	#[arg(long)]
	write_models:Option<bool>,
	#[arg(long)]
	write_scripts:Option<bool>,
}

#[derive(Clone,clap::ValueEnum)]
enum CookieType{
	Literal,
	Environment,
	File,
}

#[derive(Clone,Copy,Debug,clap::ValueEnum)]
enum Style{
	Rox,
	Rojo,
	RoxRojo,
}
impl Style{
	fn rox(&self)->rox_compiler::Style{
		match self{
			Style::Rox=>rox_compiler::Style::Rox,
			Style::Rojo=>rox_compiler::Style::Rojo,
			Style::RoxRojo=>rox_compiler::Style::RoxRojo,
		}
	}
}

#[tokio::main]
async fn main()->AResult<()>{
	let cli=Cli::parse();
	match cli.command{
		Commands::DownloadHistory(subcommand)=>download_history(DownloadHistoryConfig{
			continue_from_versions:subcommand.continue_from_versions.unwrap_or(false),
			end_version:subcommand.end_version,
			start_version:subcommand.start_version.unwrap_or(0),
			output_folder:subcommand.output_folder.unwrap_or_else(||std::env::current_dir().unwrap()),
			cookie:Cookie::from_type(subcommand.cookie_type,subcommand.cookie).await?.0,
			asset_id:subcommand.asset_id,
		}).await,
		Commands::Download(subcommand)=>{
			let output_folder=subcommand.output_folder.unwrap_or_else(||std::env::current_dir().unwrap());
			download_list(
				Cookie::from_type(subcommand.cookie_type,subcommand.cookie).await?.0,
				subcommand.asset_ids.into_iter().map(|asset_id|{
					let mut path=output_folder.clone();
					path.push(asset_id.to_string());
					(asset_id,path)
				}).collect()
			).await
		},
		Commands::DownloadDecompile(subcommand)=>{
			download_decompile(DownloadDecompileConfig{
				cookie:Cookie::from_type(subcommand.cookie_type,subcommand.cookie).await?.0,
				asset_id:subcommand.asset_id,
				output_folder:subcommand.output_folder.unwrap_or_else(||std::env::current_dir().unwrap()),
				style:subcommand.style.rox(),
				write_template:subcommand.write_template.unwrap_or(false),
				write_models:subcommand.write_models.unwrap_or(false),
				write_scripts:subcommand.write_scripts.unwrap_or(true),
			}).await
		},
		Commands::DownloadGroupInventoryJson(subcommand)=>download_group_inventory_json(
			Cookie::from_type(subcommand.cookie_type,subcommand.cookie).await?.0,
			subcommand.group,
			subcommand.output_folder.unwrap_or_else(||std::env::current_dir().unwrap()),
		).await,
		Commands::Create(subcommand)=>create(CreateConfig{
			cookie:Cookie::from_type(subcommand.cookie_type,subcommand.cookie).await?.0,
			group:subcommand.group,
			input_file:subcommand.input_file,
			model_name:subcommand.model_name,
			description:subcommand.description.unwrap_or_else(||String::with_capacity(0)),
			free_model:subcommand.free_model.unwrap_or(false),
			allow_comments:subcommand.allow_comments.unwrap_or(false),
		}).await,
		Commands::Upload(subcommand)=>upload_list(
			Cookie::from_type(subcommand.cookie_type,subcommand.cookie).await?.0,
			subcommand.group,
			vec![(subcommand.asset_id,subcommand.input_file)]
		).await,
		Commands::Compile(subcommand)=>compile(CompileConfig{
			input_folder:subcommand.input_folder.unwrap_or_else(||std::env::current_dir().unwrap()),
			output_file:subcommand.output_file,
			template:subcommand.template,
			style:subcommand.style.map(|s|s.rox()),
		}).await,
		Commands::CompileUpload(subcommand)=>compile_upload(CompileUploadConfig{
			input_folder:subcommand.input_folder.unwrap_or_else(||std::env::current_dir().unwrap()),
			template:subcommand.template,
			style:subcommand.style.map(|s|s.rox()),
			cookie:Cookie::from_type(subcommand.cookie_type,subcommand.cookie).await?.0,
			group:subcommand.group,
			asset_id:subcommand.asset_id,
		}).await,
		Commands::Decompile(subcommand)=>decompile(DecompileConfig{
			style:subcommand.style.rox(),
			input_file:subcommand.input_file,
			output_folder:subcommand.output_folder.unwrap_or_else(||std::env::current_dir().unwrap()),
			write_template:subcommand.write_template.unwrap_or(false),
			write_models:subcommand.write_models.unwrap_or(false),
			write_scripts:subcommand.write_scripts.unwrap_or(true),
		}).await,
		Commands::DecompileHistoryIntoGit(subcommand)=>decompile_history_into_git(DecompileHistoryConfig{
			git_committer_name:subcommand.git_committer_name,
			git_committer_email:subcommand.git_committer_email,
			input_folder:subcommand.input_folder,
			output_folder:std::env::current_dir()?,
			style:subcommand.style.rox(),
			write_template:subcommand.write_template.unwrap_or(false),
			write_models:subcommand.write_models.unwrap_or(false),
			write_scripts:subcommand.write_scripts.unwrap_or(true),
		 }).await,
		Commands::DownloadAndDecompileHistoryIntoGit(subcommand)=>download_and_decompile_history_into_git(DownloadAndDecompileHistoryConfig{
			git_committer_name:subcommand.git_committer_name,
			git_committer_email:subcommand.git_committer_email,
			cookie:Cookie::from_type(subcommand.cookie_type,subcommand.cookie).await?.0,
			asset_id:subcommand.asset_id,
			output_folder:std::env::current_dir()?,
			style:subcommand.style.rox(),
			write_template:subcommand.write_template.unwrap_or(false),
			write_models:subcommand.write_models.unwrap_or(false),
			write_scripts:subcommand.write_scripts.unwrap_or(true),
		 }).await,
	}
}

struct Cookie(String);
impl Cookie{
	async fn from_type(cookie_type:CookieType,cookie_string:String)->AResult<Self>{
		Ok(Self(format!(".ROBLOSECURITY={}",match cookie_type{
			CookieType::Literal=>cookie_string,
			CookieType::Environment=>std::env::var(cookie_string)?,
			CookieType::File=>tokio::fs::read_to_string(cookie_string).await?,
		})))
	}
}

struct CreateConfig{
	cookie:String,
	model_name:String,
	description:String,
	input_file:PathBuf,
	group:Option<u64>,
	free_model:bool,
	allow_comments:bool,
}

async fn create(config:CreateConfig)->AResult<()>{
	let resp=RobloxContext::new(config.cookie)
	.create(rbx_asset::context::CreateRequest{
		name:config.model_name,
		description:config.description,
		ispublic:config.free_model,
		allowComments:config.allow_comments,
		groupId:config.group,
	},tokio::fs::read(config.input_file).await?).await?;
	println!("UploadResponse={:?}",resp);
	Ok(())
}

async fn upload_list(cookie:String,group:Option<u64>,asset_id_file_map:AssetIDFileMap)->AResult<()>{
	let context=RobloxContext::new(cookie);
	//this is calling map on the vec because the closure produces an iterator of futures
	futures::stream::iter(asset_id_file_map.into_iter()
	.map(|(asset_id,file)|{
		let context=&context;
		async move{
			Ok((asset_id,context.upload(rbx_asset::context::UploadRequest{
				assetid:asset_id,
				name:None,
				description:None,
				ispublic:None,
				allowComments:None,
				groupId:group,
			},tokio::fs::read(file).await?).await?))
		}
	}))
	.buffer_unordered(CONCURRENT_REQUESTS)
	.for_each(|b:AResult<_>|async{
			match b{
				Ok((asset_id,body))=>{
					println!("asset_id={} UploadResponse={:?}",asset_id,body);
				},
				Err(e)=>eprintln!("ul error: {}",e),
			}
		}).await;
	Ok(())
}

async fn download_list(cookie:String,asset_id_file_map:AssetIDFileMap)->AResult<()>{
	let context=RobloxContext::new(cookie);
	futures::stream::iter(asset_id_file_map.into_iter()
	.map(|(asset_id,file)|{
		let context=&context;
		async move{
			Ok((file,context.download(rbx_asset::context::DownloadRequest{asset_id,version:None}).await?))
		}
	}))
	.buffer_unordered(CONCURRENT_REQUESTS)
	.for_each(|b:AResult<_>|async{
			match b{
				Ok((dest,data))=>{
					match tokio::fs::write(dest,data).await{
						Err(e)=>eprintln!("fs error: {}",e),
						_=>(),
					}
				},
				Err(e)=>eprintln!("dl error: {}",e),
			}
		}).await;
	Ok(())
}

async fn get_inventory_pages(context:&RobloxContext,group:u64)->AResult<Vec<InventoryItem>>{
	let mut cursor:Option<String>=None;
	let mut asset_list=Vec::new();
	loop{
		let mut page=context.inventory_page(rbx_asset::context::InventoryPageRequest{group,cursor}).await?;
		asset_list.append(&mut page.data);
		if page.nextPageCursor.is_none(){
			break;
		}
		cursor=page.nextPageCursor;
	}
	Ok(asset_list)
}

async fn download_group_inventory_json(cookie:String,group:u64,output_folder:PathBuf)->AResult<()>{
	let context=RobloxContext::new(cookie);
	let item_list=get_inventory_pages(&context,group).await?;

	let mut path=output_folder.clone();
	path.set_file_name("versions.json");
	tokio::fs::write(path,serde_json::to_string(&item_list)?).await?;

	Ok(())
}

async fn get_version_history(context:&RobloxContext,asset_id:AssetID)->AResult<Vec<AssetVersion>>{
	let mut cursor:Option<String>=None;
	let mut asset_list=Vec::new();
	loop{
		let mut page=context.history_page(rbx_asset::context::HistoryPageRequest{asset_id,cursor}).await?;
		asset_list.append(&mut page.data);
		if page.nextPageCursor.is_none(){
			break;
		}
		cursor=page.nextPageCursor;
	}
	asset_list.sort_by(|a,b|a.assetVersionNumber.cmp(&b.assetVersionNumber));
	Ok(asset_list)
}

struct DownloadHistoryConfig{
	continue_from_versions:bool,
	end_version:Option<u64>,
	start_version:u64,
	output_folder:PathBuf,
	cookie:String,
	asset_id:AssetID,
}

async fn download_history(mut config:DownloadHistoryConfig)->AResult<()>{
	let mut asset_list_contents=std::collections::HashSet::new();
	let mut asset_list:Vec<AssetVersion>=Vec::new();
	if config.end_version.is_none()&&config.continue_from_versions{
		//load prexisting versions list
		let mut versions_path=config.output_folder.clone();
		versions_path.push("versions.json");
		match std::fs::File::open(versions_path){
			Ok(versions_file)=>asset_list.append(&mut serde_json::from_reader(versions_file)?),
			Err(e)=>match e.kind(){
				std::io::ErrorKind::NotFound=>Err(anyhow::Error::msg("Cannot continue from versions.json - file does not exist"))?,
				_=>Err(e)?,
			}
		}
		//write down which versions are contained
		for asset_version in &asset_list{
			asset_list_contents.insert(asset_version.assetVersionNumber);
		}
		//find the highest number
		match asset_list.iter().map(|asset_version|asset_version.assetVersionNumber).max(){
			Some(max)=>{
				//count down contiguously until a number is missing
				for i in (1..=max).rev(){
					if !asset_list_contents.contains(&i){
						//that is end_version
						config.end_version=Some(i);
						break;
					}
				}
				//if all versions are contained, set start_version to the max + 1
				if config.end_version.is_none(){
					config.start_version=max+1;
				}
			},
			None=>Err(anyhow::Error::msg("Cannot continue from versions.json - there are no previous versions"))?,
		}
	}
	let context=RobloxContext::new(config.cookie);

	//limit concurrent downloads
	let mut join_set=tokio::task::JoinSet::new();

	//poll paged list of all asset versions
	let mut cursor:Option<String>=None;
	loop{
		let mut page=context.history_page(rbx_asset::context::HistoryPageRequest{asset_id:config.asset_id,cursor}).await?;
		let context=&context;
		let output_folder=config.output_folder.clone();
		let data=&page.data;
		let asset_list_contents=&asset_list_contents;
		let join_set=&mut join_set;
		let error_catcher=||async move{
		let mut cancel_paging=false;
		for asset_version in data{
			let version_number=asset_version.assetVersionNumber;
			//skip assets beyond specified end_version
			if config.end_version.is_some_and(|v|v<version_number){
				continue;
			}
			//skip assets lower than start_version and cancel paging asset versions
			if version_number<config.start_version{
				cancel_paging=true;
				continue;//don't trust roblox returned order
			}
			//skip previously downloaded assets
			if asset_list_contents.contains(&version_number){
				continue;
			}
			while CONCURRENT_REQUESTS<=join_set.len(){
				join_set.join_next().await.unwrap()??;
			}
			let context=context.clone();
			let mut path=output_folder.clone();
			path.push(format!("{}_v{}.rbxl",config.asset_id,version_number));
			join_set.spawn(async move{
				let file=context.download(rbx_asset::context::DownloadRequest{asset_id:config.asset_id,version:Some(version_number)}).await?;

				tokio::fs::write(path,file).await?;

				Ok::<_,anyhow::Error>(())
			});
		}
		Ok::<_,anyhow::Error>(cancel_paging)
		};
		let cancel_paging=match error_catcher().await{
			Ok(cancel)=>cancel,
			Err(e)=>{
				println!("download error: {}",e);
				//cancel download and write versions
				true
			},
		};
		if page.nextPageCursor.is_none()||cancel_paging{
			for asset_version in page.data.into_iter(){
				if !(asset_list_contents.contains(&asset_version.assetVersionNumber)
				||config.end_version.is_some_and(|v|v<asset_version.assetVersionNumber)
				||asset_version.assetVersionNumber<config.start_version){
					asset_list.push(asset_version);
				}
			}
			break;
		}else{
			asset_list.append(&mut page.data);
		}
		cursor=page.nextPageCursor;
	}

	asset_list.sort_by(|a,b|a.assetVersionNumber.cmp(&b.assetVersionNumber));

	let mut path=config.output_folder.clone();
	path.set_file_name("versions.json");
	tokio::fs::write(path,serde_json::to_string(&asset_list)?).await?;

	while let Some(result)=join_set.join_next().await{
		result??;
	}

	Ok(())
}

fn load_dom<R:Read>(input:R)->AResult<rbx_dom_weak::WeakDom>{
	let mut buf=std::io::BufReader::new(input);
	let peek=std::io::BufRead::fill_buf(&mut buf)?;
	match &peek[0..4]{
		b"<rob"=>{
			match &peek[4..8]{
				b"lox!"=>rbx_binary::from_reader(buf).map_err(anyhow::Error::msg),
				b"lox "=>rbx_xml::from_reader_default(buf).map_err(anyhow::Error::msg),
				other=>Err(anyhow::Error::msg(format!("Unknown Roblox file type {:?}",other))),
			}
		},
		_=>Err(anyhow::Error::msg("unsupported file type")),
	}
}


struct DecompileConfig{
	style:rox_compiler::Style,
	input_file:PathBuf,
	output_folder:PathBuf,
	write_template:bool,
	write_models:bool,
	write_scripts:bool,
}

async fn decompile(config:DecompileConfig)->AResult<()>{
	//rules:
	//Class Script|LocalScript|ModuleScript->$Name.lua
	//Class Model->$Name.rbxmx
	//overrides.json per-folder [Override{name,class}]
	//Everything else goes into template.rbxlx

	//read file
	let dom=load_dom(std::io::BufReader::new(std::fs::File::open(config.input_file)?))?;
	let context=rox_compiler::DecompiledContext::from_dom(dom);

	//generate folders, models, and scripts
	//delete models and scripts from dom
	context.write_files(rox_compiler::WriteConfig{
		style:config.style,
		output_folder:config.output_folder,
		write_template:config.write_template,
		write_models:config.write_models,
		write_scripts:config.write_scripts,
	}).await?;

	Ok(())
}

struct DownloadDecompileConfig{
	cookie:String,
	asset_id:AssetID,
	style:rox_compiler::Style,
	output_folder:PathBuf,
	write_template:bool,
	write_models:bool,
	write_scripts:bool,
}

async fn download_decompile(config:DownloadDecompileConfig)->AResult<()>{
	let context=RobloxContext::new(config.cookie);
	let file=context.download(rbx_asset::context::DownloadRequest{asset_id:config.asset_id,version:None}).await?;

	let dom=load_dom(std::io::Cursor::new(file))?;
	let context=rox_compiler::DecompiledContext::from_dom(dom);

	context.write_files(rox_compiler::WriteConfig{
		style:config.style,
		output_folder:config.output_folder,
		write_template:config.write_template,
		write_models:config.write_models,
		write_scripts:config.write_scripts,
	}).await?;

	Ok(())
}

struct WriteCommitConfig{
	git_committer_name:String,
	git_committer_email:String,
	output_folder:PathBuf,
	style:rox_compiler::Style,
	write_template:bool,
	write_models:bool,
	write_scripts:bool,
}

async fn write_commit(config:WriteCommitConfig,b:Result<AResult<(AssetVersion,rox_compiler::DecompiledContext)>,tokio::task::JoinError>,repo:&git2::Repository)->AResult<()>{
	let (asset_version,context)=b??;
	println!("writing files for version {}",asset_version.assetVersionNumber);

	//clean output dir
	if config.write_models||config.write_scripts{
		let mut src=config.output_folder.clone();
		src.push("src");
		match std::fs::remove_dir_all(src){
			Ok(())=>(),
			Err(e)=>println!("remove_dir_all src failed {}",e),
		}
	}
	if config.write_template{
		let mut template=config.output_folder.clone();
		template.push("template.rbxlx");
		match std::fs::remove_file(template){
			Ok(())=>(),
			Err(e)=>println!("remove_file template.rbxlx failed {}",e),
		}
	}

	//write files
	context.write_files(rox_compiler::WriteConfig{
		style:config.style,
		output_folder:config.output_folder.clone(),
		write_template:config.write_template,
		write_models:config.write_models,
		write_scripts:config.write_scripts,
	}).await?;

	let date=asset_version.created;
	//let sig=repo.signature()?; //this pulls default name and email
	let sig=git2::Signature::new(config.git_committer_name.as_str(),config.git_committer_email.as_str(),&git2::Time::new(date.timestamp(),0)).unwrap();
	let tree_id={
		let mut tree_index = repo.index()?;
		match tree_index.add_all(std::iter::once(config.output_folder.as_path()),git2::IndexAddOption::DEFAULT,None){
			Ok(_)=>(),
			Err(e)=>println!("tree_index.add_all error: {}",e),
		}
		match tree_index.update_all(std::iter::once(config.output_folder.as_path()),None){
			Ok(_)=>(),
			Err(e)=>println!("tree_index.update_all error: {}",e),
		}
		tree_index.write()?;
		tree_index.write_tree()?
	};
	let tree=repo.find_tree(tree_id)?;

	let mut parents=Vec::new();

	match repo.head(){
		Ok(reference)=>{
			let commit=reference.peel_to_commit()?;

			//test tree against commit tree to see if there is any changes
			let commit_tree=commit.tree()?;
			let diff=repo.diff_tree_to_tree(Some(&commit_tree),Some(&tree),None)?;
			if diff.get_delta(0).is_none(){
				println!("no changes");
				return Ok(());
			}

			parents.push(commit);
		},
		Err(e)=>println!("repo head error {:?}",e),
	};

	repo.commit(
		Some("HEAD"),//update_ref
		&sig,//author
		&sig,//commiter
		&format!("v{}", asset_version.assetVersionNumber),//message
		&tree,//tree (basically files)
		parents.iter().collect::<Vec<&git2::Commit<'_>>>().as_slice(),//parents
	)?;

	//commit
	Ok(())
}

struct DecompileHistoryConfig{
	git_committer_name:String,
	git_committer_email:String,
	input_folder:PathBuf,
	style:rox_compiler::Style,
	output_folder:PathBuf,
	write_template:bool,
	write_models:bool,
	write_scripts:bool,
}

async fn decompile_history_into_git(config:DecompileHistoryConfig)->AResult<()>{
	//use prexisting versions list
	let mut versions_path=config.input_folder.clone();
	versions_path.push("versions.json");
	let asset_list:Vec<AssetVersion>=serde_json::from_reader(std::fs::File::open(versions_path)?)?;

	let repo=git2::Repository::init(config.output_folder.as_path())?;

	//decompile all versions
	futures::stream::iter(asset_list.into_iter()
	.map(|asset_version|{
		let mut file_path=config.input_folder.clone();
		tokio::task::spawn_blocking(move||{
			file_path.push(format!("{}_v{}.rbxl",asset_version.assetId,asset_version.assetVersionNumber));
			let file=std::fs::File::open(file_path)?;
			let dom=load_dom(file)?;
			let contents=rox_compiler::DecompiledContext::from_dom(dom);
			Ok::<_,anyhow::Error>((asset_version,contents))
		})
	}))
	.buffered(CONCURRENT_DECODE)
	.for_each(|join_handle_result|async{
		match write_commit(WriteCommitConfig{
			git_committer_name:config.git_committer_name.clone(),
			git_committer_email:config.git_committer_email.clone(),
			style:config.style,
			output_folder:config.output_folder.clone(),
			write_template:config.write_template,
			write_models:config.write_models,
			write_scripts:config.write_scripts,
		},join_handle_result,&repo).await{
			Ok(())=>(),
			Err(e)=>println!("decompile/write/commit error: {}",e),
		}
	}).await;
	Ok(())
}

struct DownloadAndDecompileHistoryConfig{
	cookie:String,
	asset_id:AssetID,
	git_committer_name:String,
	git_committer_email:String,
	style:rox_compiler::Style,
	output_folder:PathBuf,
	write_template:bool,
	write_models:bool,
	write_scripts:bool,
}

async fn download_and_decompile_history_into_git(config:DownloadAndDecompileHistoryConfig)->AResult<()>{
	let context=RobloxContext::new(config.cookie);

	//poll paged list of all asset versions
	let asset_list=get_version_history(&context,config.asset_id).await?;

	let repo=git2::Repository::init(config.output_folder.clone())?;

	//download all versions
	let asset_id=config.asset_id;
	futures::stream::iter(asset_list.into_iter()
	.map(|asset_version|{
		let context=context.clone();
		tokio::task::spawn(async move{
			let file=context.download(rbx_asset::context::DownloadRequest{asset_id,version:Some(asset_version.assetVersionNumber)}).await?;
			let dom=load_dom(std::io::Cursor::new(file))?;
			Ok::<_,anyhow::Error>((asset_version,rox_compiler::DecompiledContext::from_dom(dom)))
		})
	}))
	.buffered(CONCURRENT_DECODE)
	.for_each(|join_handle_result|async{
		match write_commit(WriteCommitConfig{
			style:config.style,
			git_committer_name:config.git_committer_name.clone(),
			git_committer_email:config.git_committer_email.clone(),
			output_folder:config.output_folder.clone(),
			write_template:config.write_template,
			write_models:config.write_models,
			write_scripts:config.write_scripts,
		},join_handle_result,&repo).await{
			Ok(())=>(),
			Err(e)=>println!("download/unzip/decompile/write/commit error: {}",e),
		}
	}).await;
	Ok(())
}

struct CompileConfig{
	input_folder:PathBuf,
	output_file:PathBuf,
	template:Option<PathBuf>,
	style:Option<rox_compiler::Style>,
}

async fn compile(config:CompileConfig)->AResult<()>{
	//basically decompile in reverse order
	//load template dom
	let mut dom=match config.template{
		//mr dom doesn't like tokio files
		Some(template_path)=>load_dom(std::io::BufReader::new(std::fs::File::open(template_path)?))?,
		None=>rbx_dom_weak::WeakDom::new(rbx_dom_weak::InstanceBuilder::new("DataModel")),
	};

	rox_compiler::compile(rox_compiler::CompileConfig{
		input_folder:config.input_folder,
		style:config.style,
	},&mut dom).await?;

	let mut output_place=config.output_file.clone();
	if output_place.extension().is_none()&&tokio::fs::try_exists(output_place.as_path()).await?{
		output_place.push("place.rbxl");
	}
	let output=std::io::BufWriter::new(std::fs::File::create(output_place)?);
	//write inner objects
	rbx_binary::to_writer(output,&dom,dom.root().children())?;
	Ok(())
}

struct CompileUploadConfig{
	input_folder:PathBuf,
	template:Option<PathBuf>,
	style:Option<rox_compiler::Style>,
	cookie:String,
	group:Option<u64>,
	asset_id:AssetID,
}
async fn compile_upload(config:CompileUploadConfig)->AResult<()>{
	let mut dom=match config.template{
		//mr dom doesn't like tokio files
		Some(template_path)=>load_dom(std::io::BufReader::new(std::fs::File::open(template_path)?))?,
		None=>rbx_dom_weak::WeakDom::new(rbx_dom_weak::InstanceBuilder::new("DataModel")),
	};

	rox_compiler::compile(rox_compiler::CompileConfig{
		input_folder:config.input_folder,
		style:config.style,
	},&mut dom).await?;

	//make a binary file in a buffer in memory
	let mut data=Vec::new();
	rbx_binary::to_writer(std::io::Cursor::new(&mut data),&dom,dom.root().children())?;

	//upload it
	let context=RobloxContext::new(config.cookie);
	context.upload(rbx_asset::context::UploadRequest{
		assetid:config.asset_id,
		name:None,
		description:None,
		ispublic:None,
		allowComments:None,
		groupId:config.group,
	},data).await?;
	Ok(())
}