-- ## Modul:Tutorials is a Lua Libary to manage Wikipedia-Tutorials ##
-- Please use this module via Vorlage:Tutorials only!
-- Modul:Tutorials requires a customisable config.json, passed via the parameter config to each function call
-- The Default is Wikipedia:Tutorial/config.json

-- Helper Functions

-- Local functions and vars

local configData, templateData, rootNode
local currentTitle, currentNode, refNode, lastNode, nextNode 
local isAllPage
local currentPageNo = 0
local totalPageNo = 0
local isLastNode = false
local showHidden = false
local inited = false

function init(configPage)
    if inited then return end
    inited = true

    --mw.log('Lua Init')

    currentTitle = mw.title.getCurrentTitle()       
    if not configPage then configPage = 'Wikipedia:Tutorial/config.json' end
    configData = mw.text.jsonDecode( mw.title.new(configPage):getContent() )

    rootNode = configData.structure
    refNode = rootNode
    templateData = configData.templates

    local previousNode
    function initNode(node, i, parentNode)
        node.index = i
        node.childCount = 0
        node.title = mw.title.new(node.page)
        node.isCurrentPage = mw.title.equals( currentTitle, node.title )
        node.containsCurrentPage = node.isCurrentPage
        --node.isAllPage = false
        node.isLastNode = false

        if not node.isCurrentPage and node.all then
            node.allTitle = mw.title.new(node.all)
            if mw.title.equals( currentTitle,  node.allTitle ) then 
                node.isCurrentPage = true
                node.isAllPage = true
            end
        end

        if previousNode then
            previousNode.nextNode = node
            node.lastNode = previousNode
            --[[ -- Funktioniert noch nicht
            if previousNode.parent == node.parent or previousNode ~= node.parent  then
            else
                previousNode.isLastNode = true
            end
            ]]--
        end
        previousNode = node

        if node.children then 
            local newChildrenArray = {}

            for childIndex, childNode in pairs( node.children ) do

                initNode(childNode, childIndex, node)

                if childNode.containsCurrentPage then
                    node.containsCurrentPage = true
                end
                if not (childNode.hidden and childNode.containsCurrentPage == false) or showHidden then
                    node.childCount = node.childCount + 1
                    newChildrenArray[node.childCount] = childNode
                end
            end
            node.children = newChildrenArray
        end        

        node.refNode = node;
        if parentNode then
            node.parent = parentNode

            if node.childCount == 0 then
                node.refNode = node.parent;
            end
        end   
        
        if node.isCurrentPage then
            currentNode = node
        end

        if node.refNode == node then
            node.isRefNode = true
        end

        return node;
    end
    
    function prepareNodeHtml(node, i, parentNode)
        if node.isCurrentPage then
            node.innerHtml = templateData.threadNaviItemActive
        else
            node.innerHtml = templateData.threadNaviItem
        end

        if isAllPage then
            node.innerHtml = node.innerHtml:gsub("§§page§§", '#' .. node.name)
        else
            node.innerHtml = node.innerHtml:gsub("§§page§§", node.page)
        end
        node.innerHtml = node.innerHtml:gsub("§§name§§", node.name)

        node.childHtml = ''        
        if node.children then 
            for childIndex, childNode in pairs( node.children ) do
                prepareNodeHtml(childNode, childIndex, node)
            end
        end

        if node.childHtml == '' then
            node.outerHtml = '<li>' .. node.innerHtml .. '</li>'
        else
            node.childHtml = '<ol style="margin-left:2.2ex;">' .. node.childHtml .. '</ol>'
            node.outerHtml = '<li>' .. node.innerHtml .. node.childHtml .. '</li>'
        end

        if parentNode then
            parentNode.childHtml = parentNode.childHtml .. node.outerHtml
        end        

        return node;
    end;
        
    initNode(rootNode, 0, false)

    if not currentNode then
        currentNode = rootNode;
    end

    refNode = currentNode.refNode
    totalPageNo = refNode.childCount
    currentPageNo = currentNode.index
    isLastNode = currentNode.isLastNode
    isAllPage = currentNode.isAllPage
    nextNode = currentNode.nextNode
    lastNode = currentNode.lastNode
    
    prepareNodeHtml(rootNode, 0)
end

function getPageContent( node, frame )
    if not node then 
        return ''
    end     
    local source, html
    source = node.title:getContent()
    html = frame:preprocess( tostring( mw.html.create( "div" ):wikitext( source ) ) )

    return '<h2>' .. node.name .. '</h2>' .. html
end

function getNodeByTitle(title, node)
    local childNode, childIndex, foundNode, isBase

    if not title then 
        return currentNode
    end

    if not node then 
        node = rootNode 
        isBase = true
    end

    if mw.title.equals( title, node.title ) then
        return node
    else
        if node.children then                 
            for childIndex, childNode in pairs( node.children ) do
                foundNode = getNodeByTitle(title, childNode)
                if foundNode then 
                    return foundNode
                end
            end
        end
        if isBase then 
            return currentNode
        else 
            return false
        end
    end
end

-- Public Interface

local p = {} 

function p.navIndex(frame)
    mw.log('Lua navIndex ', frame)

    init( frame.args[config] );
    local node = getNodeByTitle(frame.args[title])
    return node.refNode.childHtml
end

function p.navWidget(frame)    
    mw.log('Lua navWidget ', frame)
    init( frame.args[config] );

    local node = currentNode
    local pagina, btnHtml 

    if node.isAllPage == true then
        pagina = templateData.paginaAll:gsub("§§page§§", refNode.page);
    else
        pagina = templateData.pagina

        if node.isRefNode == true then
            pagina = templateData.paginaStart
        else
            pagina = templateData.pagina
        end  
        pagina = pagina:gsub("§§totalPageNo§§", node.refNode.childCount ):gsub("§§currentPageNo§§", node.index ) 
        btnHtml = ''
        mw.log('node.lastNode:',node,'.',node.lastNode,'|',previousNode)
        if node.lastNode then
            btnHtml = templateData.btnLast:gsub("§§page§§", node.lastNode.page ):gsub("§§name§§", node.lastNode.name )
        end 
        pagina = pagina:gsub("§§btnLast§§", btnHtml )
    
        btnHtml = ''
        mw.log('node.nextNode:',node,'.',node.nextNode)
        if not node.isLastNode and node.nextNode then
            btnHtml = templateData.btnNext:gsub("§§page§§", node.nextNode.page ):gsub("§§name§§", node.nextNode.name )
        end
        pagina = pagina:gsub("§§btnNext§§", btnHtml )   
    
        btnHtml = ''
        if node.refNode.all then
            btnHtml = templateData.btnAll:gsub("§§page§§", node.refNode.all )
        end

        pagina = pagina:gsub("§§btnAll§§", btnHtml )
    end

    local widgetHtml = templateData.widget:gsub("§§rootPage§§",rootNode.page):gsub("§§threadNavi§§", node.refNode.innerHtml .. node.refNode.childHtml ):gsub("§§pagina§§", pagina )

    return widgetHtml
end

function p.all(frame)
    mw.log('Lua all ', frame)
    init( frame.args[config] );
    -- body
    local html
    if currentNode then

        html = '<div class="tutorial-article" style="margin-bottom:6em;">' .. getPageContent(refNode, frame) .. '</div>'
         
        for childIndex, childNode in pairs( refNode.children ) do
            html = html .. '<div class="tutorial-article" style="margin-bottom:6em;">' .. getPageContent(childNode, frame) .. '</div>'
        end

        return html
    else
        return "not found"
    end
end

function p.isAll(frame)
    mw.log('Lua isAll ', frame)
    init( frame.args[config] );
    mw.log('Lua isAll -> ', isAllPage)
    return isAllPage
end

return p