extern crate git2;
extern crate iron;
extern crate mount;
extern crate serde_json;
extern crate staticfile;

// This example serves the docs from target/doc/staticfile at /doc/
//
// Run `cargo doc && cargo run --example doc_server`, then
// point your browser to http://127.0.0.1:3000/doc/

use std::path::{Path, PathBuf};
use std::error::Error;

use iron::prelude::{Chain, Request, Response};
use iron::{status, Iron, IronResult};
use mount::Mount;
use staticfile::Static;

use git2::Repository;

struct WebHookConfig {
    secret: String,
    repo_root: PathBuf,
    repo_prefixes: Vec<String>,
}

fn redeploy_repo(url: &str, path: &Path, name: &str) -> Result<(), git2::Error> {
    let mut new_path = path.to_path_buf();
    new_path.push(name);
    eprintln!("Cloning {} into {:?} ({:?} / {})", url, new_path, path, name);

    let repo = match Repository::open(&new_path) {
        Ok(repo) => repo,
        Err(e) => {
            eprintln!("can't open repo, going to try cloning it: {}", e.description());
            match Repository::clone(url, &new_path) {
                Ok(repo) => repo,
                Err(e) => panic!("failed to clone: {}", e),
            }
        }
    };
    repo.set_head("FETCH_HEAD")?;
    
    // repo.checkout_tree(&branch.into_reference(), Some(git2::build::CheckoutBuilder::new().force().use_theirs(true)))?;
    repo.checkout_head(Some(git2::build::CheckoutBuilder::new().force().use_theirs(true)))?;

    Ok(())
}

fn webhook(req: &mut Request, config: &WebHookConfig) -> IronResult<Response> {
    eprintln!("Webhook Request: {:?}", req);
    let wh: serde_json::Value = serde_json::from_reader(&mut req.body).unwrap();

    // Ensure we have a "Secret" parameter, and that it matches the config.
    let found_secret = wh.get("secret");
    if found_secret.is_none() {
        return Ok(Response::with(status::Unauthorized));
    }
    let found_secret = found_secret.unwrap();
    if found_secret != &config.secret {
        return Ok(Response::with(status::Unauthorized));
    }

    // Ensure the repo is valid.
    let repository = wh.get("repository");
    if repository.is_none() {
        eprintln!("No 'repository' key found");
        return Ok(Response::with(status::PreconditionRequired));
    }
    let repository = repository.unwrap();

    // Ensure there's an HTML URL that's a valid string
    let html_url = match repository.get("html_url") {
        None => {
            eprintln!("No HTML URL found");
            return Ok(Response::with(status::PreconditionRequired));
        }
        Some(s) => match s.as_str() {
            None => {
                eprintln!("HTML URL isn't a string");
                return Ok(Response::with(status::PreconditionRequired));
            }
            Some(s) => s,
        },
    };

    // Check to make sure the repo prefix is one we recognize
    let mut found_match = false;
    for prefix in &config.repo_prefixes {
        if html_url.starts_with(prefix) {
            found_match = true;
            break;
        }
    }
    if !found_match {
        eprintln!("URL doesn't start with match");
        return Ok(Response::with(status::PreconditionRequired));
    }

    // And ensure the URL is a string
    let website_url = match repository.get("website") {
        None => {
            eprintln!("The website isn't configured for this repo");
            return Ok(Response::with(status::PreconditionRequired));
        }
        Some(s) => match s.as_str() {
            None => {
                eprintln!("Website URL isn't a string");
                return Ok(Response::with(status::PreconditionRequired));
            }
            Some(s) => match iron::Url::parse(s) {
                Ok(u) => u,
                Err(e) => {
                    eprintln!("Unable to parse URL: {:?}", e);
                    return Ok(Response::with(status::PreconditionFailed));
                }
            },
        },
    };
    let target_path = match website_url.path().last() {
        Some(s) => {
            if s.is_empty() {
                eprintln!("No website URL path was found -- defaulting to \"current\"");
                "current".to_owned()
            } else {
                s.to_string()
            }
        }
        None => {
            eprintln!("No website URL path was found");
            return Ok(Response::with(status::PreconditionFailed));
        }
    };
    eprintln!("Final path: {:?} / {:?}", config.repo_root, target_path);

    if let Err(e) = redeploy_repo(html_url, &config.repo_root, &target_path) {
        eprintln!("unable to clone/update repo: {}", e.description());
        return Ok(Response::with(status::NotModified));
    }

    Ok(Response::with(status::Ok))
}

fn main() {
    let mut mount = Mount::new();
    let hostaddr = "0.0.0.0:9119".to_owned();
    let config = WebHookConfig {
        secret: "1234".to_owned(),
        repo_root: Path::new("D:\\Code\\talkserved").to_path_buf(),
        repo_prefixes: vec!["https://git.xobs.io/xobs".to_owned()],
    };

    // Serve the shared JS/CSS at /
    mount.mount("/", Static::new(config.repo_root.clone()));

    // Listen for calls to "/webhook" and process accordingly
    mount.mount(
        "/webhook",
        Chain::new(move |req: &mut Request| webhook(req, &config)),
    );

    println!("Doc server running on http://{}", hostaddr);

    Iron::new(mount).http(hostaddr).unwrap();
}