Module:Infobox television

--- @module
local p = {}

local maintenance_categories = {
 image_values_without_an_image = "[[Category:Pages using infobox television with image-related values without an image]]",
 unnecessary_title_parameter = "[[Category:Pages using infobox television with unnecessary name parameter]]",
 non_matching_title = "[[Category:Pages using infobox television with non-matching title]]",
 flag_icon = "[[Category:Pages using infobox television with flag icon]]",
 dates_incorrectly_formatted = "[[Category:Pages using infobox television with nonstandard dates]]",
 manual_display_title = "[[Category:Pages using infobox television with unnecessary manual displaytitle]]",
}

--- Returns a maintenance category if the dates aren't formatted correctly with
--- {{Start date}} and {{End date}} templates.
---
--- @param start_date string The start date parameter.
--- @param end_date string The end date parameter.
--- @return string
local function are_dates_formatted_correctly(start_date, end_date)
 if start_date and not string.find(start_date, "dtstart") then
  return maintenance_categories.dates_incorrectly_formatted
 end

 if end_date and (not string.find(end_date, "dtend") and end_date ~= "present") then
  return maintenance_categories.dates_incorrectly_formatted
 end

 return ""
end

--- Returns a maintenance category if a {{Italic title}} or {{DISPLAYTITLE}} template is used.
---
---@return string
local function has_display_title()
 local page_text = mw.title.getCurrentTitle():getContent()
 if string.find(page_text, "[Ii]talic title") or string.find(page_text, "DISPLAYTITLE") then
  return maintenance_categories.manual_display_title
 end
 return ""
end

--- Returns a maintenance category if a flag icon is used.
---
--- All the infobox values are checked.
---
--- @param args table
--- @return string
local function has_flag_icon(args)
 for _, v in pairs(args) do
  if string.find(v, "flagicon") then
   return maintenance_categories.flag_icon
  end
 end
 return ""
end

--- Returns a maintenance category if there is no image file while image auxiliary values are present.
---
--- Infobox parameters checked:
--- - |image=
--- - |image_size=
--- - |image_upright=
--- - |image_alt=
--- - |alt=
--- - |caption=
---
--- @param args table
--- @return string
local function are_image_auxiliary_values_used_for_no_image(args)
 if args.image then
  return ""
 end

 if args.image_size or args.image_upright or args.image_alt or args.alt or args.caption then
  return maintenance_categories.image_values_without_an_image
 end

 return ""
end

--- Returns a maintenance category if the infobox title is equal to the article title.
---
--- Infobox parameters checked:
--- - |name=
---
--- The function currently checks if the infobox title is equal to the article title while ignoring styling such as:
--- - nowrap spans.
--- - line breaks.
---
--- |page_title_test= is used for testing only.
---
--- @param frame table
--- @param args table
--- @return string
local function is_infobox_title_equal_to_article_title(frame, args)
 if not args.name then
  return ""
 end

 local article_title = args.page_title_test
 if not args.page_title_test then
  article_title = mw.title.getCurrentTitle().text
 end

 -- Remove disambiguation.
 local page_name, _ = string.gsub(article_title, "%s+%b()$", "")

 -- Remove nowrap span.
 if string.find(args.name, "nowrap") then
  local title = frame:expandTemplate{title = "Strip tags", args = {args.name}}
  if title == page_name then
   return ""
  end
  return maintenance_categories.non_matching_title
 end

 -- Remove line breaks and additional spaces as a result.
 if string.find(args.name, "<br%s?/?>") then
  local title, _ = string.gsub(args.name, "<br%s?/?>", "")
  title, _ = string.gsub(title, "  ", " ")
  if title == page_name then
   return ""
  end
  return maintenance_categories.non_matching_title
 end

 if args.name == page_name then
  return maintenance_categories.unnecessary_title_parameter
 end

 -- Article and infobox titles do not match.
 return maintenance_categories.non_matching_title
end

--- Returns the relevant maintenance categories based on the {{Infobox television}} values validated.
---
--- @param frame table
--- @return string
function p.validate_values(frame)
 local getArgs = require("Module:Arguments").getArgs
 local args = getArgs(frame)

 local categories = {}
 table.insert(categories, is_infobox_title_equal_to_article_title(frame, args))
 table.insert(categories, has_display_title())
 table.insert(categories, are_image_auxiliary_values_used_for_no_image(args))
 table.insert(categories, has_flag_icon(args))
 table.insert(categories, are_dates_formatted_correctly(args.first_aired or args.released, args.last_aired))

 return table.concat(categories, "")
end


return p