use config::Config;
use template::Template;
use renderer;
use logger::{LogLevel, Logger};
use error::Error;

use std::fs::{create_dir_all, File};
use std::io::prelude::*;
use std::path::Path;

const DEFAULT_CSS: &'static str = include_str!("templates/default-css.css");
const PAGE_TEMPLATE: &'static str = include_str!("templates/page-template.html");
const NAVBAR_ITEM: &'static str = include_str!("templates/navbar/item-template.html");
const NAVBAR_IMAGE_ITEM: &'static str = include_str!("templates/navbar/image-item-template.html");

fn fetch_config() -> Result<Config, Error> {
    match Config::new() {
        Ok(config) => Ok(config),
        Err(err) => Err(Error::from(err)),
    }
}

fn write_file<T: Into<String>, U: Into<String>>(path_str: T, content: U) -> Result<(), Error> {
    let path_str = path_str.into();
    let content = content.into();

    let path = Path::new(&path_str);
    if let Some(parent) = path.parent() {
        create_dir_all(parent)?;
    } else {
        return Err(Error::new(
            LogLevel::SEVERE,
            format!("Could not find parent folder for {}", path_str),
        ));
    }
    if path.exists() {
        Err(Error::new(
            LogLevel::SEVERE,
            format!(
                "File already exists: {} -- Consider using overwrite-flag",
                path_str
            ),
        ))
    } else {
        match File::create(path) {
            Ok(mut file) => Ok(file.write_all(content.as_bytes()).unwrap()),
            Err(err) => Err(Error::from(err)),
        }
    }
}

pub fn build(logger: &Logger) -> Result<(), Error> {
    logger.log(LogLevel::INFO, "Starting build");
    let config = fetch_config()?;

    if config.global_config.website.use_default_css {
        logger.log(LogLevel::DETAIL, "Adding public/css/default.css");
        write_file("public/css/default.css", DEFAULT_CSS)?;
    }

    logger.log(LogLevel::INFO, "Generating page templates");
    let page_template = Template::new(PAGE_TEMPLATE);

    let mut navbar_content = String::new();
    if config.global_config.navbar.is_some() {
        let navbar_item_template = Template::new(NAVBAR_ITEM);
        let navbar_image_item_template = Template::new(NAVBAR_IMAGE_ITEM);
        logger.log(LogLevel::DETAIL, "Rendering Navbar");
        navbar_content =
            renderer::render_navbar(&config, navbar_item_template, navbar_image_item_template)?;
    }

    logger.log(LogLevel::INFO, "Rendering");
    logger.log(LogLevel::DETAILER, "Rendering public/test.html");
    let rendered = match config.get_configs_for(0) {
        Ok(page_config) => page_template.render(&Template::page_data_from(
            page_config.clone(),
            navbar_content,
            renderer::render_markdown_content(&page_config).unwrap(),
        )),
        Err(err) => panic!(err),
    };

    logger.log(LogLevel::INFO, "Writing");
    logger.log(LogLevel::DETAILER, "Writing public/test.html");
    write_file("public/test.html", rendered)?;

    logger.log(LogLevel::INFO, "Done!");
    Ok(())
}