extern crate chrono;
extern crate fs_extra;
extern crate htmlescape;
#[macro_use]
extern crate lazy_static;
extern crate notify;
extern crate pulldown_cmark;
extern crate regex;
extern crate toml;
extern crate uuid;

use std::sync::mpsc::channel;
use std::time::Duration;
use std::{fs, path};

use fs_extra::dir;
use notify::{DebouncedEvent, RecommendedWatcher, RecursiveMode, Watcher};
use toml::Value;

use config::Config;
use entry::{parse_entry, read_entry_dir, write_entry, write_entry_listing, Entry, EntryKind};
use rss::generate_rss;

mod config;
mod entry;
mod rss;

pub fn build(include_drafts: bool, cwd: &path::Path) {
    let config = match fs::read_to_string(cwd.join("casaubon.toml")) {
        Ok(contents) => match contents.parse::<Value>() {
            Ok(config) => Config {
                site_name: String::from(config["site_name"].as_str().unwrap()),
                url: String::from(config["url"].as_str().unwrap()),
                description: String::from(config["description"].as_str().unwrap()),
            },
            Err(_) => panic!("Invalid casaubon.toml"),
        },
        Err(_) => {
            panic!("Can't find casaubon.toml");
        }
    };

    match fs::read_dir(cwd.join("public")) {
        Ok(_) => {
            fs::remove_dir_all(cwd.join("public")).unwrap();
        }
        Err(_) => {}
    }

    fs::create_dir(cwd.join("public")).expect("Couldn't create public directory");
    fs::create_dir(cwd.join("public").join("posts")).expect("Couldn't create posts directory");

    let layout_template = fs::read_to_string(&cwd.join("templates").join("layout.html"))
        .expect("Couldn't find layout template");
    let post_template = fs::read_to_string(cwd.join("templates").join("post.html"))
        .expect("Couldn't find post template");
    let post_listing_template = fs::read_to_string(cwd.join("templates").join("post_listing.html"))
        .expect("Couldn't find post listing item template");
    let post_item_template =
        fs::read_to_string(cwd.join("templates").join("post_listing_item.html"))
            .expect("Couldn't find post listing item template");
    let page_template = fs::read_to_string(cwd.join("templates").join("page.html"))
        .expect("Couldn't find page template");

    let post_paths = match include_drafts {
        true => {
            let mut posts = read_entry_dir(&cwd.join("posts"));
            posts.append(&mut read_entry_dir(&cwd.join("drafts")));
            posts
        }
        false => read_entry_dir(&cwd.join("posts")),
    };

    let page_paths = read_entry_dir(&cwd.join("pages"));

    let mut posts: Vec<Entry> = post_paths
        .into_iter()
        .map(|entry| {
            let path = entry.path();
            let contents = fs::read_to_string(&path).expect("Couldn't read post file");
            parse_entry(EntryKind::Post, &contents, &path)
        })
        .collect::<Vec<Entry>>();

    posts.sort_by(|a, b| b.date.cmp(&a.date));

    for post in &posts {
        write_entry(&cwd, &layout_template, &post_template, &post, &config);
    }

    for entry in page_paths.into_iter() {
        let path = entry.path();
        let contents = fs::read_to_string(&path).expect("Couldn't read page file");
        let page = parse_entry(EntryKind::Page, &contents, &path);
        write_entry(&cwd, &layout_template, &page_template, &page, &config);
    }

    write_entry_listing(
        &cwd,
        &layout_template,
        &post_listing_template,
        &post_item_template,
        &posts,
        &config,
    );

    fs_extra::copy_items(
        &vec![cwd.join("assets")],
        cwd.join("public"),
        &dir::CopyOptions::new(),
    )
    .expect("Couldn't copy assets directory");

    let rss = generate_rss(&config, &posts);
    fs::write(cwd.join("public").join("rss.xml"), rss).expect("Couldn't write rss file");
}

pub fn new(name: &str, cwd: &path::Path) {
    let project_path = cwd.join(name);

    fs::create_dir(&project_path).expect(&format!("Couldn't create directory '{}'", &name));
    fs::write(
        project_path.join("casaubon.toml"),
        format!(
            "site_name = \"{}\"\nurl = \"{}.com\"\ndescription = \"\"",
            &name, &name
        ),
    )
    .expect("Could not create casaubon.toml");

    for dir in &[
        "drafts",
        "posts",
        "pages",
        "public",
        "templates",
        "assets",
        "js",
    ] {
        fs::create_dir(&project_path.join(&dir))
            .expect(&format!("Couldn't create {} directory", &dir));
    }

    let default_layout_template = format!(
        "<html>
  <head>
    <title>{}</title>
  </head>
  <body>
    <h1>{}</h1>
    {{{{ contents }}}}
  </body>
</html>\n",
        name, name
    );
    let default_post_listing_template = format!(
        "<div>
  <h3>Posts</h3>
  <ul>{{{{ post_listing }}}}</ul>
</div>\n"
    );
    let default_post_template = format!(
        "<article>
  <h1>{{{{ title }}}}</h1>
  <div>{{{{ body }}}}</div>
</article>\n"
    );
    let default_page_template = format!(
        "<article>
  <h1>{{{{ title }}}}</h1>
  <div>{{{{ body }}}}</div>
</article>\n"
    );
    let default_post_listing_item_template = format!(
        "<li>
  {{ date }} <a href=\"/posts/{{{{ slug }}}}/\">{{{{ title }}}}</a>
</li>\n"
    );

    for (filename, contents) in &[
        ("layout", &default_layout_template),
        ("post_listing", &default_post_listing_template),
        ("post", &default_post_template),
        ("page", &default_page_template),
        ("post_listing_item", &default_post_listing_item_template),
    ] {
        fs::write(
            &project_path
                .join("templates")
                .join(format!("{}.html", filename)),
            &contents,
        )
        .expect(&format!("Couldn't write templates/{}.html", filename));
    }
}

fn should_rebuild(cwd: &path::Path, path: &path::PathBuf) -> bool {
    let path_string = path.to_str().unwrap().to_string();
    let change_is_from_public = path_string.contains(cwd.join("public").to_str().unwrap());
    let change_is_from_git = path_string.contains(cwd.join(".git").to_str().unwrap());

    !change_is_from_public && !change_is_from_git
}

pub fn watch(include_drafts: bool, cwd: &path::Path) -> notify::Result<()> {
    let (tx, rx) = channel();
    let mut watcher: RecommendedWatcher = try!(Watcher::new(tx, Duration::from_secs(2)));
    try!(watcher.watch(&cwd, RecursiveMode::Recursive));
    println!("Watching {}", cwd.to_str().unwrap());

    let handle_event = |path: &path::PathBuf| {
        if should_rebuild(&cwd, &path) {
            println!("Rebuilding");
            build(include_drafts, &cwd);
        }
    };

    loop {
        match rx.recv() {
            Ok(e) => match e {
                DebouncedEvent::Create(path) => {
                    handle_event(&path);
                }
                DebouncedEvent::Write(path) => {
                    handle_event(&path);
                }
                _ => {}
            },
            Err(e) => println!("watch error: {:?}", e),
        }
    }
}

#[cfg(test)]
mod tests {
    #[allow(unused_imports)]
    use super::*;
    #[allow(unused_imports)]
    use uuid::Uuid;

    use std::env;

    #[test]
    fn test_should_rebuild() {
        let cwd = env::current_dir().unwrap();
        assert_eq!(
            false,
            should_rebuild(&cwd, &cwd.join("public").join("index.html"))
        );
        assert_eq!(
            false,
            should_rebuild(&cwd, &cwd.join(".git").join("index.html"))
        );
        assert_eq!(
            true,
            should_rebuild(&cwd, &cwd.join("posts").join("test.md"))
        );
        assert_eq!(
            true,
            should_rebuild(&cwd, &cwd.join("drafts").join("test.md"))
        );
        assert_eq!(
            true,
            should_rebuild(&cwd, &cwd.join("css").join("style.css"))
        );
        assert_eq!(true, should_rebuild(&cwd, &cwd.join("js").join("index.js")));
    }
}