Module:CodeToText

Documentation for this module may be created at Module:CodeToText/doc

-- Module:CodeToText
-- Extracts content snippets from a page using hook markers
-- 
-- Finds content between matching hooks (e.g., 🪝, 📌, 🔖, ⭐) placed at the beginning and end of desired content.
-- 
-- Example:
--   {{#invoke:CodeToText|showSnippet|page=Module:Example|hook=⭐}}

local p = {}

-- Cache for extracted snippets (persists during page render)
local snippetCache = {}

-- Helper function to create a cache key from parameters
local function createCacheKey(pageName, hook)
    return pageName .. "|hook=" .. hook
end

function p.showSnippet(frame)
    local pageName = frame.args.page
    if not pageName then
        return "Error: 'page' parameter is required"
    end
    
    local hook = frame.args.hook
    if not hook then
        return "Error: 'hook' parameter is required"
    end
    
    -- Check cache first for previously extracted snippets
    local cacheKey = createCacheKey(pageName, hook)
    if snippetCache[cacheKey] then
        return snippetCache[cacheKey]
    end

    local titleObj = mw.title.new(pageName)
    if not titleObj then
        return "Failed to create mw.title object for '" .. pageName .. "'"
    end

    local content = titleObj:getContent()
    if not content then
        return "No content for '" .. pageName .. "'"
    end

    local result
    
    -- First, check for hooks on the same line
    local inlinePattern = hook .. "(.-)" .. hook
    local inlineMatch = content:match(inlinePattern)
    
    if inlineMatch then
        -- We found inline hooks: use the content between them
        result = inlineMatch
    else
        -- Look for hooks on different lines
        local lines = {}
        local hookPositions = {}
        
        -- Find hook instances and count lines
        local lineNumber = 0
        for line in content:gmatch("[^\r\n]+") do
            lineNumber = lineNumber + 1
            
            if line:find(hook, 1, true) then
                table.insert(hookPositions, lineNumber)
            end
            
            -- Store all lines for later use
            lines[lineNumber] = line
        end
        
        if #hookPositions < 2 then
            return "Error: Need at least 2 instances of hook '" .. hook .. "' in '" .. pageName .. "'"
        end
        
        -- Extract content between first two hook instances
        local startLine = hookPositions[1]
        local endLine = hookPositions[2]
        
        -- Always exclude the hook lines
        local startIndex = startLine + 1
        local endIndex = endLine - 1
        
        -- Pre-allocate snippet table
        local snippetSize = math.max(0, endIndex - startIndex + 1)
        local snippet = {}
        
        if snippetSize > 0 then
            for i = 1, snippetSize do
                snippet[i] = lines[startIndex + i - 1]
            end
            result = table.concat(snippet, "\n")
        else
            result = ""
        end
    end
    
    -- Cache the result before returning
    snippetCache[cacheKey] = result
    return result
end

return p