use crate::parser::Body;
use crate::parser::DustTag;
use crate::parser::Template;
use crate::parser::TemplateElement;
use std::collections::HashMap;

pub struct InlinePartialTreeElement<'a> {
    parent: Option<&'a InlinePartialTreeElement<'a>>,
    blocks: HashMap<&'a str, &'a Option<Body<'a>>>,
}

impl<'a> InlinePartialTreeElement<'a> {
    pub fn new(
        parent: Option<&'a InlinePartialTreeElement<'a>>,
        blocks: HashMap<&'a str, &'a Option<Body<'a>>>,
    ) -> InlinePartialTreeElement<'a> {
        InlinePartialTreeElement {
            parent: parent,
            blocks: blocks,
        }
    }

    pub fn get_block(&self, name: &str) -> Option<&'a Option<Body<'a>>> {
        match self.blocks.get(name) {
            None => match self.parent {
                None => None,
                Some(parent_tree_element) => parent_tree_element.get_block(name),
            },
            Some(interior) => Some(interior),
        }
    }
}

pub fn extract_inline_partials<'a>(
    template: &'a Template<'a>,
) -> HashMap<&'a str, &'a Option<Body<'a>>> {
    let mut blocks: HashMap<&'a str, &'a Option<Body<'a>>> = HashMap::new();

    extract_inline_partials_from_body(&mut blocks, &template.contents);

    blocks
}

fn extract_inline_partials_from_body<'a, 'b>(
    blocks: &'b mut HashMap<&'a str, &'a Option<Body<'a>>>,
    body: &'a Body<'a>,
) {
    for elem in &body.elements {
        match elem {
            TemplateElement::TEIgnoredWhitespace(_) => (),
            TemplateElement::TESpan(_span) => (),
            TemplateElement::TETag(dt) => {
                extract_inline_partials_from_tag(blocks, dt);
            }
        }
    }
}

fn extract_inline_partials_from_tag<'a, 'b>(
    blocks: &'b mut HashMap<&'a str, &'a Option<Body<'a>>>,
    tag: &'a DustTag,
) {
    match tag {
        DustTag::DTComment(..) => (),
        DustTag::DTSpecial(..) => (),
        DustTag::DTLiteralStringBlock(..) => (),
        DustTag::DTReference(..) => (),
        DustTag::DTSection(container) => {
            match &container.contents {
                None => (),
                Some(body) => extract_inline_partials_from_body(blocks, &body),
            };
            match &container.else_contents {
                None => (),
                Some(body) => extract_inline_partials_from_body(blocks, &body),
            };
        }
        DustTag::DTExists(container) => {
            match &container.contents {
                None => (),
                Some(body) => extract_inline_partials_from_body(blocks, &body),
            };
            match &container.else_contents {
                None => (),
                Some(body) => extract_inline_partials_from_body(blocks, &body),
            };
        }
        DustTag::DTNotExists(container) => {
            match &container.contents {
                None => (),
                Some(body) => extract_inline_partials_from_body(blocks, &body),
            };
            match &container.else_contents {
                None => (),
                Some(body) => extract_inline_partials_from_body(blocks, &body),
            };
        }
        DustTag::DTPartial(..) => (),
        DustTag::DTInlinePartial(named_block) => {
            blocks.insert(&named_block.path.keys[0], &named_block.contents);
        }
        DustTag::DTBlock(..) => (),
        DustTag::DTHelperEquals(parameterized_block)
        | DustTag::DTHelperNotEquals(parameterized_block)
        | DustTag::DTHelperGreaterThan(parameterized_block)
        | DustTag::DTHelperLessThan(parameterized_block)
        | DustTag::DTHelperGreaterThanOrEquals(parameterized_block)
        | DustTag::DTHelperLessThanOrEquals(parameterized_block)
        | DustTag::DTHelperSep(parameterized_block)
        | DustTag::DTHelperFirst(parameterized_block)
        | DustTag::DTHelperLast(parameterized_block)
        | DustTag::DTHelperSelect(parameterized_block)
        | DustTag::DTHelperAny(parameterized_block)
        | DustTag::DTHelperNone(parameterized_block) => {
            match &parameterized_block.contents {
                None => (),
                Some(body) => extract_inline_partials_from_body(blocks, &body),
            };
            match &parameterized_block.else_contents {
                None => (),
                Some(body) => extract_inline_partials_from_body(blocks, &body),
            };
        }
    }
}