feat: use_poisson_pkgdown()

DESCRIPTION

@@ -21,3 +21,7 @@ Suggests:
     knitr,
     rmarkdown
 VignetteBuilder: knitr
+Imports: 
+    cli,
+    desc,
+    yaml

NAMESPACE

@@ -1,3 +1,4 @@
 # Generated by roxygen2: do not edit by hand
 
 export(ruler)
+export(use_poisson_pkgdown)

R/use-poisson-pkgdown.R

@@ -0,0 +1,59 @@
+#' Set up poissontemplate usage
+#'
+#' This function
+#' * registers poissontemplate usage in the pkgdown config;
+#' * explains what the next steps are.
+#'
+#' @param pkg Path to package
+#'
+#' @return None
+#' @export
+#'
+use_poisson_pkgdown <- function(pkg = getwd()) {
+  cat(paste(cli::symbol$info, sprintf("Working in %s\n", pkg)))
+
+  current_needs <- desc::desc_get("Config/Needs/website")
+  needs <- if (!is.na(current_needs)) {
+    toString(c(as.character(current_needs), "poissonconsulting/poissontemplate"))
+  } else {
+    "poissonconsulting/poissontemplate"
+  }
+  desc::desc_set("Config/Needs/website" = needs)
+  cat(paste(cli::symbol$tick, "Registered GHA dependency on poissontemplate.\n"))
+
+  config_path <- find_pkgdown_config(pkg)
+  if (is.null(config_path)) {
+    meta <- list(
+      template = list(package = "poissontemplate")
+    )
+    yaml::write_yaml(meta, file.path(pkg, "_pkgdown.yml"))
+  } else {
+    config <- yaml::read_yaml(config_path)
+    config$template$package <- "poissontemplate"
+    config$template$params$bootswatch <- NULL
+    config$template$includes$before_title <- NULL
+    if (!is.null(config$template$bootstrap)) {
+      config$template$bootstrap <- 5
+    }
+    yaml::write_yaml(config, file.path(pkg, config_path))
+  }
+  cat(paste(cli::symbol$tick, "Registered poissontemplate in pkgdown config.\n"))
+  cat(paste(cli::symbol$bullet, "Check that the config edits are all harmless.\n"))
+  cat(paste(cli::symbol$bullet, "Git commit and push to origin.\n"))
+
+  # TODO: traffic analytics setup?
+}
+
+find_pkgdown_config <- function(pkg) {
+  possible_paths <- c(
+    "_pkgdown.yml", "_pkgdown.yaml",
+    "pkgdown/_pkgdown.yml", "pkgdown/_pkgdown.yaml",
+    "inst/_pkgdown.yml", "inst/_pkgdown.yaml"
+  )
+  for (path in possible_paths) {
+    if (file.exists(file.path(pkg, path))) {
+      return(path)
+    }
+  }
+  NULL
+}

README.md

@@ -8,29 +8,6 @@
 poissontemplate provides a custom [pkgdown](https://pkgdown.r-lib.org/) template for Poisson consulting packages. 
 Please don’t use it for your own package.
 
-## Setup
-
-### Register the use of the template
-
-In `_pkgdown.yml` that you can create through `usethis::use_pkgdown()` if absent,
-have these lines:
-
-```yaml
-template:
-  package: poissontemplate
-```
-
-### For continuous integration
-
-For all sites, ensure that DESCRIPTION contains:
-
-```yaml
-Config/Needs/website: poissonconsulting/poissontemplate
-```
-
-by editing the file manually or by running `desc::desc_set("Config/Needs/website", "poissonconsulting/poissontemplate")`.
-
-
 ## Installation
 
 You can install the development version of poissontemplate from [GitHub](https://github.com/) with:
@@ -40,6 +17,14 @@ You can install the development version of poissontemplate from [GitHub](https:/
 pak::pak("poissonconsulting/poissontemplate")
 ```
 
+## Setup
+
+In every package where you need to set up poissontemplate usage, run
+
+``` r
+poissontemplate::use_poisson_pkgdown()
+```
+
 ## Relevant resources
 
 - pkgdown documentation about theming: https://pkgdown.r-lib.org/articles/customise.html#theming