use std::io::Read;

use crate::{config::{TciServerConfig, TciScriptConfig}, error::TciError, git::{shell_out, RefUpdate, RefUpdateVecHelper}};

lazy_static::lazy_static!{
	static ref HOME : String = std::env::var("HOME").unwrap_or_default();
}

pub fn tci(cfg: TciServerConfig) -> Result<(), Box<dyn std::error::Error>> {
	let repo_path = std::path::PathBuf::from(&std::env::var("GIT_DIR")?);

	// check which branches are being updated
	let mut input = String::new();
	std::io::stdin().read_to_string(&mut input)?;

	let updates : Vec<RefUpdate> = input.split('\n')
		.filter_map(|l| {
			let split : Vec<&str> = l.split(' ').collect();
			Some(RefUpdate {
				from:   (*split.get(0)?).to_string(),
				to:     (*split.get(1)?).to_string(),
				branch: (*split.get(2)?).to_string(),
			})
		})
		.collect();

	if let Some(branch) = cfg.branch {
		if !updates.contains_branch(&branch) {
			return Ok(()); // tci is not allowed to run on changes for this branch
		}
	}

	// check config before even creating temp dir and cloning repo
	let git_config = git2::Config::open(&repo_path.join("config"))?;
	let tci_script = git_config.get_str("tci.script").unwrap_or(".tci").to_string();

	// check if CI is allowed
	if !cfg.allow_all
		&& !cfg.run_setup_even_if_not_allowed
		&& !git_config.get_bool("tci.allow").unwrap_or(false)
	{
		return Ok(()); // we are in whitelist mode and this repo is not whitelisted
	}

	// run hooks
	for setup in cfg.setup {
		println!("[+] setting up ({setup})");
		shell_out(setup)?;
	}

	if !cfg.allow_all && !git_config.get_bool("tci.allow").unwrap_or(false) {
		return Ok(()); // ewwww!!! ugly fix to allow running cgit update-agefile on every repo anyway
	}

	let res = tci_hook(&repo_path, &updates, tci_script);

	for cleanup in cfg.cleanup {
		println!("[-] cleaning up ({cleanup}) ");
		shell_out(cleanup)?;
	}

	res?; // only check error AFTER running cleanup hooks

	println!("[o] script run successfully");

	Ok(())
}

pub fn tci_hook(repo_path: &std::path::Path, updates: &Vec<RefUpdate>, tci_script: String) -> Result<(), TciError> {
	// TODO kind of ew but ehh should do its job
	let mut name = repo_path.to_string_lossy()
		.replace(HOME.as_str(), "");
	if name.starts_with('/') {
		name.remove(0);
	}
	if name.ends_with('/') {
		name.remove(name.chars().count());
	}

	let tmp = tempdir::TempDir::new(&format!("tci-{}", name.replace('/', "_")))?;

	// TODO allow customizing clone? just clone recursive? just let hook setup submodules?
	git2::Repository::clone(
		repo_path.to_str()
			.ok_or(TciError::FsError("repo path is not a valid string"))?,
		tmp.path(),
	)?;

	let tci_path = tmp.path().join(&tci_script);
	let tci_config_path = tmp.path().join(tci_script + ".toml");

	if tci_config_path.is_file() { // if .tci.toml is a config file, parse it for advanced CI options
		let tci_config_raw = std::fs::read_to_string(tci_config_path)?;
		let tci_config : TciScriptConfig = toml::from_str(&tci_config_raw)?;
		if let Some(branch) = tci_config.branch {
			if !updates.contains_branch(&branch) {
				return Ok(()); // tci script should not be invoked for this branch
			}
		}
		println!("[=] running tci pipeline for repo '{name}'");
		Ok(())
	} else if tci_path.is_file() { // if .tci is just one script, simply run it
		println!("[=] running tci script for repo '{name}'");
		std::env::set_current_dir(tmp.path())?;
		let res = shell_out(tci_path);
		std::env::set_current_dir(repo_path)?;
		res
	} else { 
		return Err(TciError::MissingScript);
	}
}