quiz + Documenter

# Multiple Choice

```@setup quiz
using Mustache, Markdown, Random

abstract type Question end
mutable struct Numericq <: Question
    val
    tol
    reminder
    answer_text
    m
    M
    units
    hint
end

mutable struct Radioq <: Question
    choices
    answer
    reminder
    answer_text
    values
    labels
    hint
    inline
end

function numericq(val, tol=1e-3, reminder="", args...;
                  hint="", units::AbstractString="")

    answer_text= "[$(round(val-tol,digits=5)), $(round(val+tol,digits=5))]"
    Numericq(val, tol, reminder, answer_text, val-tol, val+tol, units, hint)
end

numericq(val::Int; kwargs...) = numericq(val, 0; kwargs...)

# for choice questions
function radioq(choices, answer, reminder="", answer_text=nothing;
                hint="", inline::Bool=(hint!=""),
                keep_order::Bool=false)
    inds = collect(1:length(choices))
    values = copy(inds)
    labels = choices
    !keep_order && shuffle!(inds)

    Radioq(choices[inds], findfirst(isequal(answer), inds), reminder,
           answer_text, values, labels[inds], hint, inline)
end

function booleanq(ans::Bool, reminder="", answer_text=nothing;labels::Vector=["true", "false"], hint::AbstractString="", inline::Bool=true)
    choices = labels[1:2]
    ans = 2 - ans
    radioq(choices, ans, reminder, answer_text; hint=hint,
           inline=inline, keep_order=true)
end

html_templates = Dict()
html_templates["Numericq"] = mt"""
<form class="mx-2 my-3" name='WeaveQuestion' data-id='{{ID}}' data-controltype='{{TYPE}}'>
<div class='form-group {{status}}'>
<div class='controls'>
{{{form}}}
{{#hint}}
<span class='help-inline'><i id='{{ID}}_hint' class='icon-gift'></i></span>
<script>$('#{{ID}}_hint').tooltip({title:'{{{hint}}}', html:true, placement:'right'});</script>
{{/hint}}

<div class="form-floating input-group">
<input id="{{ID}}" type="number" class="form-control" placeholder="Numeric answer">
<label for="{{ID}}">Numeric answer</label>
{{#units}}<span class="input-group-addon mx-2">{{{units}}}</span>{{/units}}
</div>

<div id='{{ID}}_message'></div>
</div>
</div>
</form>
<script text='text/javascript'>
document.getElementById("{{ID}}").addEventListener("change", function() {
  var correct = {{{correct}}};
  var msgBox = document.getElementById('{{ID}}_message');
  if(correct) {
    msgBox.innerHTML = "<div class='pluto-output admonition note alert alert-success'><span class='glyphicon glyphicon-thumbs-up'>👍&nbsp;Correct</span></div>";
  } else {
    msgBox.innerHTML = "<div class='pluto-output admonition alert alert-danger'><span class='glyphicon glyphicon-thumbs-down'>👎&nbsp; Incorrect</span></div>";
  }
});
</script>
"""

html_templates["Radioq"] = mt"""
{{#items}}
<div class="form-check">
  <input class="form-check-input" type="radio" name="radio_{{ID}}" id="radio_{{ID}}_{{value}}" value="{{value}}">
    {{{label}}}
</div>
{{/items}}
"""
html_templates["radio_script_tpl"] = """
document.querySelectorAll('input[name="radio_{{ID}}"]').forEach(function(rb) {
rb.addEventListener("change", function() {
    var correct = rb.value == {{correct_answer}};
    var msgBox = document.getElementById('{{ID}}_message');
    if (correct) {
    msgBox.innerHTML = "<div class='pluto-output admonition note alert alert-success'><span class='glyphicon glyphicon-thumbs-up'>👍&nbsp;Correct</span></div>";
  } else {
    msgBox.innerHTML = "<div class='pluto-output admonition alert alert-danger'><span class='glyphicon glyphicon-thumbs-down'>👎&nbsp; Incorrect</span></div>";
  }
})});
"""

html_templates["question_tpl"] = mt"""
<form  class="mx-2 my-3" name="WeaveQuestion" data-id="{{ID}}" data-controltype="{{TYPE}}">
<div class="form-group {{status}}">
{{{form}}}
{{#hint}}
<i class="bi bi-gift-fill"></i>

<!--<script>$("#{{ID}}_hint").tooltip({title:"{{{hint}}}", html:true, placement:"right"});</script>-->
{{/hint}}
<div id="{{ID}}_message"></div>
</div>
</form>
<script text="text/javascript">
{{{script}}}
</script>
"""


function Base.show(io::IO, m::MIME"text/html", x::Numericq)
#function Base.show(io::IO, x::Numericq)
    ID = randstring()
    Mustache.render(io, html_templates["Numericq"],
                    Dict("ID" => ID,
                         "TYPE" => "numeric",
                         "selector" => "#" * ID,
                         "status" => "",
                         "hint" => x.hint,
                         "units" => x.units,
                         "correct" => "Math.abs(this.value - $(x.val)) <= $(x.tol)"
                         ))

end

function _markdown_to_html(x)
    length(x) == 0 && return("")
    x = Markdown.parse(x)
    x = sprint(io -> Markdown.html(io, x))
    return x
end

function _make_item(i, choice)
    choice′ = sprint(io -> Markdown.html(io, Markdown.parse(choice)))
    # strip <p> tag
    choice′ = chomp(choice′)
    choice′ = replace(choice′, r"^<p>" => "")
    choice′ = replace(choice′, r"</p>$" => "")


    item = Dict("no"=>i,
                "label"=> choice′,
                "value"=>i
                )
end


function Base.show(io::IO, m::MIME"text/html", x::Radioq)
#function Base.show(io::IO,  x::Radioq)
    ID = randstring()

    tpl = html_templates["Radioq"]
    choices = string.(x.choices)
    items = Dict[]

    ## make items
    items = [_make_item(i, choice) for (i,choice) ∈ enumerate(choices)]

    script = Mustache.render(html_templates["radio_script_tpl"],
                             Dict("ID"=>ID,
                                  "correct_answer" => x.answer,
                                  "selector" => "input:radio[name='radio_$ID']",
                                  "correct" => "this.value == $(x.answer)"))

    form = Mustache.render(tpl, Dict("ID"=>ID, "items"=>items,
                                 "inline" => x.inline ? " inline" : ""
                                 ))

    Mustache.render(io, html_templates["question_tpl"],
                    Dict("form" => form,
                         "script" => script,
                         "TYPE" => "radio",
                         "ID" => ID,
                         "hint"=> _markdown_to_html(x.hint)))

end
```


# Number

What is 2 + 2

```@example quiz
answer = 2 + 2 # hide
numericq(answer) #hide
```

What is ``\sqrt{2}``?

```@example quiz
answer = sqrt(2) # hide
numericq(answer, 1e-2) # hide
```

## select on

What is "one"?

```@example quiz
choices = ["``1``", "``2^2``", raw"``\sqrt{3}``"] # hide
answer = 1 # hide
radioq(choices, answer, keep_order=true) # hide
```