---
title: "Toulmin Diagram"
author: "Russell Almond"
date: "8/26/2021"
output: html_document
runtime: shiny
---

```{r setup, include=FALSE}
knitr::opts_chunk$set(echo = TRUE)
library(DiagrammeR)
```

The Toulmin diagram was design by legal scholar Stephen Toulmin to describe an argument.  
## Inputs and Outputs



```{r diagram, echo=FALSE}
inputPanel(
  textAreaInput('claim',"Claim:",placeholder="Proposition to establish\n Should pass clairity test."),
  textAreaInput('data',"Data:",placeholder="Observation to support/refute claim."),
  textAreaInput('warrant',"Warrant:",placeholder="Reasons which data is related to claim."),
  textAreaInput('back',"Backing:",placeholder="Reasons for believing warrant."),
  textAreaInput('alt',"Alternative:",placeholder="Reasons claim might not correspond to data."),
  textAreaInput('rebut',"Rebuttal:",placeholder="Reasons for believing alternative.")
)

toulmin <- function (claim, data, warrant, alt, back="", rebut="") {
  paste(
    'igraph Toulmin {',
    'rankdir="BT";',
    'node [shape="rectangle"];',
    paste('claim [label="Claim:',claim,'"]'),
    paste('warrant [label="Warrant:',warrant,'"]'),
    paste('alt [label="Alternative:',alt,'"]'),
    paste('back [label="Backing:',back,'"]'),
    paste('rebut [label="Rebuttal:',rebut,'"]'),
    paste('data [label="Data:',data,'"]'),
    'junction1, junction2 [fixedsize="true", height=0, width=0, style="invis"]',
    'spacer1, spacer2, spacer3, spacer4 [fixedsize="true", height=0, width=0, style="invis"]',
    '{rank="max"; spacer1, claim, spacer2}',
    'spacer1 -> claim -> spacer2 [style="invis"]',
    '{rank="same"; warrant, junction1, alt}',
    'spacer1->warrant, spacer2 -> alt [style="invis"]',
    '{rank="same"; back, junction2, rebut}',
    'back -> junction2 -> rebut [style="invis"]',
    '{rank="min"; spacer3, data, spacer4}',
    'spacer3 -> data -> spacer4 [style="invis"]',
    'back->spacer3, rebut -> spacer4 [style="invis"]',
    'data -> junction2 -> junction1 [dir="none"]',
    'junction1 ->  claim [label="so"]',
    'subgraph cluser_1 {',
        'warrant -> junction1 [label="since"]',
        'junction1 -> alt [dir="back", label="unless"]',
    '}',
    'back -> warrant [label="supports"]',
    'rebut -> alt [label="supports"]',
    '}', sep='\n')
}
DiagrammeR::DiagrammeROutput(outputId = "diagram", width = "950px", height = "auto")

output$diagram <- 
  DiagrammeR::renderDiagrammeR({
    DiagrammeR::grViz(
        paste0(toulmin(input$claim,input$data,input$warrant,input$alt,
                              input$back, input$rebut)))
})

textOutput("code")
output$code <- renderPrint(toulmin(input$claim,input$data,input$warrant,input$alt,
                              input$back, input$rebut))
```