Module:Reading time

-- Calculate estimated reading time for any page rounded to multiple of 5. Outputs "X-Y minutes".
-- invoke on any page or template with {{#invoke:Reading time|estimateReadingTime|YourPageHere}} (change YourPageHere)

local p = {}
local mw = require("mw")

function p.estimateReadingTime(frame)
    -- Get the page title from the frame parameter
    local pageTitle = frame.args[1]

    -- Ensure that pageTitle is a string
    if type(pageTitle) == "string" then
        -- Use MediaWiki's built-in function to get the page content
        local content = mw.title.new(pageTitle):getContent()

        -- Ensure that content is a string
        if type(content) == "string" then
            -- Count words using a more robust pattern
            local wordCount = 0
            for word in content:gmatch("%S+") do
                wordCount = wordCount + 1
            end

            -- Define the range of reading speeds
            local minSpeed = 160
            local maxSpeed = 238

            -- Calculate reading times for both minimum and maximum speeds
            local minReadingTime = math.floor(wordCount / maxSpeed)
            local maxReadingTime = math.ceil(wordCount / minSpeed)

            -- Round the reading times to the nearest multiple of 5
            minReadingTime = math.floor(minReadingTime / 5) * 5
            maxReadingTime = math.ceil(maxReadingTime / 5) * 5
            
            -- Ensure that minReadingTime is at least 1
            if minReadingTime == 0 then
               minReadingTime = 1
            end

            -- Create the reading time string
            local readingTime = minReadingTime .. "-" .. maxReadingTime .. " minutes"

            return readingTime
        else
            return "Error: Invalid content"
        end
    else
        return "Error: Invalid page title"
    end
end

return p