//! A collection of metadata used during site generation.

use chrono::{Datelike, Utc};
use maud::{html, Markup, PreEscaped, Render};
use std::fs;
use typed_builder::TypedBuilder;

/// Represents a logo.
pub struct LogoLink<'a> {
    /// The link the logo will resolve to when clicked.
    pub url: &'a str,
    /// The url of the logo picture.
    pub logo: &'a str,
    /// Alternative text if the logo cannot be loaded.
    pub alt_text: &'a str,
    /// Text accompanying the logo.
    pub text: &'a str,
}
impl<'a> Render for LogoLink<'a> {
    fn render(&self) -> Markup {
        html! {
            a.link-anchor href=(self.url) {
                img.link-logo src=(self.logo) alt=(self.alt_text); (self.text)
            }
        }
    }
}

/// Data used during site generation for things like css, scripts, contact info and menus. Most are
/// for meta tags.
#[derive(TypedBuilder)]
pub struct MetaData<'a> {
    /// Language of the website.
    #[builder(default = "en-US")]
    pub lang: &'a str,
    /// Encoding of the website.
    #[builder(default = "UTF-8")]
    pub charset: &'a str,
    /// Scripts to include in the website.
    #[builder(default_code = "&[]")]
    pub scripts: &'a [Script<'a>],
    /// CSS to include in the website.
    #[builder(default=&[])]
    pub css: &'a [Css<'a>],
    /// The title of the website.
    #[builder(default = "Benjamin Xu")]
    pub title: &'a str,
    /// The description of the website.
    #[builder(default = "Benjamin Xu's personal site.")]
    pub description: &'a str,
    /// The copyright data of the website.
    #[builder(default_code = r#"Copyright {
        name: &Name {
            first: "Benjamin",
            middle: Some("Peiyan"),
            last: "Xu",
            nicknames: &[],
        },
        icon: "©",
        rights_clause: "All rights reserved",
    }"#)]
    pub copyright: Copyright<'a>,
    /// The menu of the website.
    #[builder(default)]
    pub menu: Option<&'a Menu<'a>>,
    /// The points of contact for the owner of the website.
    #[builder(default)]
    pub contact: Option<&'a Contact<'a>>,
    /// The logo of the website.
    #[builder(default)]
    pub logo: Option<&'a Logo<'a>>,
    /// The theme color of the website. Affects mobile address name bars.
    #[builder(default = "#00003f")]
    pub theme_color: &'a str,
}
impl<'a> Default for MetaData<'a> {
    fn default() -> Self {
        Self::builder().build()
    }
}
/// Information regarding the logo. (This is very simple).
pub struct Logo<'a> {
    /// The url to the actual image.
    pub src: &'a str,
    pub href: Option<&'a str>,
}
impl<'a> Render for Logo<'a> {
    fn render(&self) -> Markup {
        html! {
            div.logo {
                @match self.href {
                    Some(link) => a.logo-wrapper href=(link) {
                        img.logo-img src=(self.src);
                    },
                    None => img.logo-img src=(self.src);,
                }
            }
        }
    }
}
/// Information regarding the `<script>` tags to include.
pub enum Script<'a> {
    /// Represents a script externally linked (in the `public/js` directory).
    External(&'a str),
    /// Represents a script copy and pasted into the website.
    Embedded(&'a str),
}
impl<'a> Render for Script<'a> {
    fn render(&self) -> Markup {
        match self {
            Script::External(src) => html! { script defer?[true] src={ "/public/js/"(src) } {} },
            Script::Embedded(src) => html! { script { (PreEscaped(src)) } },
        }
    }
}
impl<'a> Script<'a> {
    /// A default script loading wasm glue for my wasm code.
    pub fn wasm_bindgen_loader(name: &str) -> (String, String) {
        let glue = format!("wasm-bindgen-glue/{}.js", name);
        let load = format!("\
             document.addEventListener(\
                \"DOMContentLoaded\",\
                function(){{\
                    var mod = wasm_bindgen(\"/public/wasm/{}_bg.wasm\").catch(function(e) {{ console.log(\"Promise received from wasm load.\"); console.log(e); e.catch(function(e) {{ console.log(e) }}) }});\
                    if (mod.load_listeners) {{\
                        var listeners = mod.load_listeners();\
                    }}\
                }}\
             );\
            ",
            name
        );
        (glue, load)
    }
}
/// Information regarding the `<style>` tags to include.
pub enum Css<'a> {
    /// Above the fold CSS. This get linked in from the resources directory, `/public`.
    Critical { src: &'a str },
    /// Under the fold CSS. This get linked in from the resources directory, `/public`.
    NonCritical { src: &'a str },
}
impl<'a> Render for Css<'a> {
    fn render(&self) -> Markup {
        match self {
            Css::NonCritical { src } => html! { link rel="stylesheet" href={
                "/public/css/"(src)".css"
            }{} },
            Css::Critical { src } => {
                let style = fs::read_to_string(format!("./public/css/{}.css", src).as_str())
                    .unwrap_or_else(|src| panic!("./public/css/{}.css is missing", src));
                html! { style { (PreEscaped(style)) } }
            }
        }
    }
}
/// A email address.
pub struct Email<'a> {
    /// The username portion of the email.
    pub user: &'a str,
    /// The domain portion of the email.
    pub domain: &'a str,
}
impl<'a> Render for Email<'a> {
    fn render(&self) -> Markup {
        html! {
            (self.user)"@"(self.domain)
        }
    }
}
/// A phone number. This is an enum for globalization.
pub enum PhoneNumber<'a> {
    /// A phone number in the US.
    US {
        /// The area code.
        area_code: u16,
        /// The prefix (the three numbers after the area code).
        prefix: u16,
        /// The line number (the four numbers after the area code).
        line_number: u16,
        /// A link to the icon for this number. (Work, Mobile, etc.)
        icon: &'a str,
    },
}
impl<'a> Render for PhoneNumber<'a> {
    fn render(&self) -> Markup {
        match self {
            PhoneNumber::US {
                icon,
                area_code,
                prefix,
                line_number,
            } => html! {
                (icon)": ("(area_code)") "(prefix)"-"(line_number)
            },
        }
    }
}
/// A contact card. Comprised of emails and phone numbers.
pub struct Contact<'a> {
    /// Emails for this contact.
    pub email: &'a [Email<'a>],
    /// Phone numbers for this contact.
    pub phone: &'a [PhoneNumber<'a>],
}
impl<'a> Render for Contact<'a> {
    fn render(&self) -> Markup {
        html! {
            @for email in self.email {
                p.contact-email { "Email: " (email) }
            }
            @for phone in self.phone {
                p.contact-phone-number { "Phone: " (phone) }
            }
        }
    }
}
/// A struct representing names.
pub struct Name<'a> {
    /// First name.
    pub first: &'a str,
    /// Middle name.
    pub middle: Option<&'a str>,
    /// Last name.
    pub last: &'a str,
    /// A list of nicknames.
    pub nicknames: &'a [&'a str],
}
impl<'a> Render for Name<'a> {
    fn render(&self) -> Markup {
        html! {
            (self.first) " " @if let Some(middle) = self.middle {
                @if let Some(initial) = middle.chars().next() {
                    (initial)
                }
            } ". " (self.last)
        }
    }
}
/// Copyright data.
pub struct Copyright<'a> {
    /// Person copyrighting the website.
    pub name: &'a Name<'a>,
    /// The copyright icon to be used.
    pub icon: &'a str,
    /// What rights to grant/refuse.
    pub rights_clause: &'a str,
}
impl<'a> Render for Copyright<'a> {
    fn render(&self) -> Markup {
        let year = Utc::now().year();
        let start_year = year - 1;
        let end_year = year + 1;
        html! {
            p.copyright { (self.icon) " " (start_year) "-" (end_year) " " (self.name) ". " (self.rights_clause) "." }
        }
    }
}
/// An entry in the menu.
pub struct MenuItem<'a> {
    /// Text to display.
    pub text: &'a str,
    /// Where the entry links to, if it links to one.
    pub link: Option<&'a str>,
    /// A child menu, if one exists.
    pub children: Option<&'a Menu<'a>>,
}
impl<'a> MenuItem<'a> {
    /// Render a link to [`Markup`] if present.
    fn render_possible_link(link: Option<&str>, text: &str) -> Markup {
        html! {
            @if let Some(link) = link {
                a href=(link) { (text) }
            } @else {
                (text)
            }
        }
    }
}
impl<'a> Render for MenuItem<'a> {
    fn render(&self) -> Markup {
        html! {
            li {
                (MenuItem::render_possible_link(self.link, self.text))
                @if let Some(children) = self.children {
                    (children)
                }
            }
        }
    }
}
/// A newtype for a list of [`MenuItem`](crate::data::MenuItem)s.
pub struct Menu<'a>(pub &'a [MenuItem<'a>]);
impl<'a> Render for Menu<'a> {
    fn render(&self) -> Markup {
        html! {
            nav.menu {
                ul {
                    @for item in self.0.iter() {
                        (item)
                    }
                }
            }
        }
    }
}
impl<'a> Render for &Menu<'a> {
    fn render(&self) -> Markup {
        (*self).render()
    }
}
impl<'a> Menu<'a> {
    pub fn into_string(self) -> String {
        self.render().into_string()
    }
}