---
--- Contains functionality to perform 'Filling' operations against existing Data by way of finding and nesting
---   additional Groups where necessary to provide feedback on available content which is not actually
---   Sourced in every possible available Location
--- Dependencies: Cache, Table, Runner, Callback
---

local appName, app = ...

local CurrentSkipLevel = 0	-- Whether to skip certain cost items
-- Returns the current Skip Level
app.GetSkipLevel = function()
	return CurrentSkipLevel
end
-- Assigns a Skip Level to be used when Fill operations take place. This is to reduce extremely excessive bloated lists
-- due to huge amounts of Sources for some Cost groups
-- 0 	- (default, never skipped)
-- 1 	- (tooltip, skipped unless within tooltip/popout)
-- 1.5	- (tooltip root, skipped unless tooltip root or within popout)
-- 2 	- (popout, skipped unless within popout)
-- 2.5 	- (popout root, skipped unless root of popout)
app.SetSkipLevel = function(level)
	-- print("SkipPurchases exclusion",level)
	CurrentSkipLevel = level or 0
end

-- Currently, Classic does not use any of the following Fill logic but the above
-- SkipLevel functions are referenced within Classic files
if app.IsClassic then return end




local wipe,pairs,ipairs,rawget,math_floor
	= wipe,pairs,ipairs,rawget,math.floor

-- App locals
local SearchForObject, SearchForField, GetRelativeValue, ArrayAppend, AssignChildren
	= app.SearchForObject, app.SearchForField, app.GetRelativeValue, app.ArrayAppend, app.AssignChildren

-- OnLoad locals
local CreateObject, ResolveSymbolicLink, PriorityNestObjects, NPCExpandHeaders, ForceFillDB
app.AddEventHandler("OnLoad", function()
	CreateObject = app.__CreateObject
	ResolveSymbolicLink = app.ResolveSymbolicLink
	PriorityNestObjects = app.PriorityNestObjects
	NPCExpandHeaders = app.HeaderData.FILLNPCS or app.EmptyTable
	ForceFillDB = app.ForceFillDB
end)

-- ItemID's which should be skipped when filling purchases with certain levels of 'skippability'
local SkipPurchases = {
	-- 0 	- (default, never skipped)
	-- 1 	- (tooltip, skipped unless within tooltip/popout)
	-- 1.5	- (tooltip root, skipped unless tooltip root or within popout)
	-- 2 	- (popout, skipped unless within popout)
	-- 2.5 	- (popout root, skipped unless root of popout)
	itemID = {
		[137642] = 2.5,	-- Mark of Honor
		[21100] = 1,	-- Coin of Ancestry
		[23247] = 1,	-- Burning Blossom
		[33226] = 1,	-- Tricky Treat
		[37829] = 1,	-- Brewfest Prize Token
		[49927] = 1,	-- Love Token
	},
	currencyID = {
		[515] = 1,		-- Darkmoon Prize Ticket
		[1166] = 1,		-- Timewarped Badge
		[2778] = 2.5,		-- Bronze
	},
	LearnedTypes = {
		Toy = 1,
		Recipe = 1,
		RecipeWithItem = 1,
		Mount = 1,
		BattlePet = 1,
	}
}
local function ShouldFillPurchases(group, FillData)
	local val
	for key,values in pairs(SkipPurchases) do
		val = group[key]
		if val then
			val = values[val]
			if not val then return true end
			if (FillData.SkipLevel or CurrentSkipLevel) < val - (group == FillData.Root and 0.5 or 0) then
				return
			end
		end
	end
	return true;
end

-- Determines searches required for upgrades using this group
local function DetermineUpgradeGroups(group, FillData)
	local nextUpgrade = group.nextUpgrade;
	if nextUpgrade then
		if not nextUpgrade.collected then
			group.filledUpgrade = true;
		end
		-- app.PrintDebug("filledUpgrade=",nextUpgrade.modItemID,nextUpgrade.collected,"<",group.modItemID)
		local o = CreateObject(nextUpgrade);
		return { o };
	end
end
-- Determines searches required for costs using this group
local function DeterminePurchaseGroups(group, FillData)
	-- do not fill purchases on certain items, can skip the skip though based on a level
	if not ShouldFillPurchases(group, FillData) then return end

	-- Certain Collected Types which are NOT the Root of the Fill should not be filled
	if SkipPurchases.LearnedTypes[group.__type] and group ~= FillData.Root and group.collected then
		-- app.PrintDebug("Don't Fill purchases for non-Root collected Toy",app:SearchLink(group))
		return
	end

	local collectibles = group.costCollectibles;
	if collectibles and #collectibles > 0 then
		-- if app.Debugging then
		-- 	local sourceGroup = app.CreateRawText("RAW COLLECTIBLES", {
		-- 		["OnUpdate"] = app.AlwaysShowUpdate,
		-- 		["skipFill"] = true,
		-- 		["g"] = {},
		-- 	})
		-- 	NestObjects(sourceGroup, collectibles, true)
		-- 	NestObject(group, sourceGroup, nil, 1)
		-- end
		local groupHash = group.hash;
		-- app.PrintDebug("DeterminePurchaseGroups",app:SearchLink(group),"-collectibles",collectibles and #collectibles);
		local groups = {};
		local clone;
		for _,o in ipairs(collectibles) do
			if o.hash ~= groupHash then
				-- app.PrintDebug("Purchase @",app:SearchLink(o))
				clone = CreateObject(o);
				groups[#groups + 1] = clone
			end
		end
		-- app.PrintDebug("DeterminePurchaseGroups-final",groups and #groups);
		-- mark this group as no-longer collectible as a cost since its cost collectibles have been determined
		if #groups > 0 then
			group.collectibleAsCost = false;
			group.filledCost = true;
			group.costTotal = nil;
		end
		return groups;
	end
end
-- Used with recipeID to make distinct itemID combinations, must be 1 order of magnitude greater than the highest recipeID
local RECIPEMOD_THRESHOLD = 10000000
local function DetermineRecipeOutputGroups(group, FillData)
	local recipeID = group.recipeID;
	if not recipeID then return end
	-- only fill root recipes or those marked as 'fillable'
	if not group.fillable and FillData.Root ~= group then return end

	-- this would be more efficient as a RecipeDB instead if that becomes a thing
	local info
	for reagent,recipes in pairs(app.ReagentsDB) do
		info = recipes[recipeID]
		if info then break end
	end
	if not info then return end

	local skipLevel = FillData.SkipLevel or 0
	-- track crafted items which are filled across the entire fill sequence
	local craftedItems = FillData.CraftedItems

	local recipeMod = recipeID / RECIPEMOD_THRESHOLD
	local craftedItemID = info[1];
	if craftedItemID and not craftedItems[craftedItemID]
		and not craftedItems[craftedItemID + recipeMod] and skipLevel > 1 then
		craftedItems[craftedItemID + recipeMod] = true
		local search = SearchForObject("itemID",craftedItemID,"field")
		search = (search and CreateObject(search)) or app.CreateItem(craftedItemID)
		-- app.PrintDebug("DetermineRecipeOutput",search.hash,app:SearchLink(group),"=>",app:SearchLink(search))
		return {search}
	end
end
local function DetermineCraftedGroups(group, FillData)
	local itemID = group.itemID;
	local itemRecipes = app.ReagentsDB[itemID];
	-- if we're filling a window (level 2) for a Reagent
	-- then we will allow showing the same crafted item multiple times
	-- so that different reagents can all be visible for the same purpose
	local expandedNesting = (FillData.SkipLevel or 0) > 1 and FillData.FillRecipes
	-- if not itemRecipes then return; end
	if not itemRecipes then
		if expandedNesting then
			return DetermineRecipeOutputGroups(group, FillData)
		end
		return
	end

	local craftableItemIDs = {}
	-- track crafted items which are filled across the entire fill sequence
	local craftedItems = FillData.CraftedItems
	if FillData.Root == group then
		craftedItems[itemID] = true
	end
	local craftedItemID, recipe, skillID

	-- If needing to filter by skill due to BoP reagent, then check via recipe cache instead of by crafted item
	-- If the reagent itself is BOP, then only show things you can make.
	-- 2024-08-15: Revised: instead of changing what is filled (affected by filtering) instead always fill everything possible
	-- and include necessary filtering information for each output, i.e. the skillID on outputs
	-- this should filter properly based on ignoring filters on BoE items & using Debug/Account mode without having to refill

	local groups = {};
	-- find recipe(s) which creates this item
	for recipeID,info in pairs(itemRecipes) do
		craftedItemID = info[1];
		-- app.PrintDebug(app:RawSearchLink("itemID",itemID),"x",info[2],"=>",app:RawSearchLink("itemID",craftedItemID),"via",app:RawSearchLink("spellID",recipeID));
		if craftedItemID and not craftableItemIDs[craftedItemID] and (expandedNesting or not craftedItems[craftedItemID]) then
			-- app.PrintDebug("recipeID",recipeID);
			recipe = SearchForObject("recipeID",recipeID,"key") or app.CreateRecipe(recipeID)
			if recipe then
				if expandedNesting then
					recipe = app.CreateNonCollectibleWithGroups(recipe)
					recipe.fillable = true
					groups[#groups + 1] = recipe
				else
					-- crafted items should be considered unique per recipe
					-- recipes are 1M+ now :O
					craftableItemIDs[craftedItemID + (recipeID / RECIPEMOD_THRESHOLD)] = recipe;
				end
			else
				-- app.PrintDebug("Unsourced recipeID",recipe);
				-- we don't have the Recipe sourced, so just include the crafted item anyway
				craftableItemIDs[craftedItemID] = true;
			end
		-- else app.PrintDebug("Skipped, already listed")
		end
	end

	if not expandedNesting then
		local search
		for craftedItemID,recipe in pairs(craftableItemIDs) do
			craftedItemID = math_floor(craftedItemID)
			craftedItems[craftedItemID] = true
			skillID = recipe ~= true and GetRelativeValue(recipe, "skillID") or nil
			-- Searches for a filter-matched crafted Item
			search = SearchForObject("itemID",craftedItemID,"field");
			search = (search and CreateObject(search)) or app.CreateItem(craftedItemID)
			-- link the respective crafted item object to the skill required by the crafting recipe
			search.requireSkill = skillID
			-- app.PrintDebug("craftedItemID",app:RawSearchLink("itemID",craftedItemID),"via skill",app:RawSearchLink("professionID",skillID),skillID)
			groups[#groups + 1] = search
		end
	end

	-- app.PrintDebug("DetermineCraftedGroups",app:SearchLink(group),groups and #groups);
	if #groups > 0 then
		group.filledReagent = true;
	end
	return groups;
end
local function GetAllNestedGroupsByFunc(results, groups, func)
	local g
	for _,o in ipairs(groups) do
		if func(o) then results[#results + 1] = o end
		g = o.g
		if g then
			for _,t in ipairs(g) do
				GetAllNestedGroupsByFunc(results, t, func)
			end
		end
	end
end
local function GetNpcIDForDrops(group)
	-- assuming for any 'crs' references on an encounter/header group that all crs are linked to the same resulting content
	-- Fyrakk Assaults uses two headers with 'crs' test that when changing this check
	return group.npcID or group.creatureID or ((group.encounterID or group.isWorldQuest) and group.crs and group.crs[1])
end
local function DetermineSymlinkGroups(group)
	if group.sym then
		-- app.PrintDebug("DSG-Now",app:SearchLink(group));
		local groups = ResolveSymbolicLink(group);
		-- make sure this group doesn't waste time getting resolved again somehow
		group.sym = nil;
		if groups and #groups > 0 then
			-- flag all nested symlinked content so that any NPC groups do not nest NPC data
			local results = {}
			GetAllNestedGroupsByFunc(results, groups, GetNpcIDForDrops)
			for _,o in ipairs(results) do
				o.NestNPCDataSkip = true
			end
		end
		-- app.PrintDebug("DSG",groups and #groups);
		return groups;
	end
end
local function GetRelativeFieldInSet(group, field, set)
	if group then
		local val = group[field]
		return set[val] and val or GetRelativeFieldInSet(group.sourceParent or group.parent, field, set);
	end
end
-- Pulls in Common drop content for specific NPCs if any exists
-- (so we don't need to always symlink every NPC which is included in common boss drops somewhere)
local function DetermineNPCDrops(group, FillData)
	if not FillData.NestNPCData or group.NestNPCDataSkip then return end
	local npcID = GetNpcIDForDrops(group)
	if not npcID then return end
	-- app.PrintDebug("NPC Group",app:SearchLink(group),npcID)
	-- search for groups of this NPC
	local npcGroups = SearchForField("npcID", npcID);
	if not npcGroups or #npcGroups == 0 then return end
	-- see if there's a difficulty wrapping the fill group
	local difficultyID = GetRelativeValue(group, "difficultyID");
	if difficultyID then
		-- app.PrintDebug("FillNPC.Diff",difficultyID)
		-- can only fill npc groups for the npc which match the difficultyID
		local headerID, groups, npcDiff;
		for _,npcGroup in ipairs(npcGroups) do
			if npcGroup.hash ~= group.hash then
				headerID = GetRelativeFieldInSet(npcGroup, "headerID", NPCExpandHeaders);
				-- app.PrintDebug("DropCheck",app:SearchLink(npcGroup),"=>",headerID)
				-- where headerID is allowed and the nested difficultyID matches
				if headerID then
					npcDiff = GetRelativeValue(npcGroup, "difficultyID");
					-- copy the header under the NPC groups
					if not npcDiff or npcDiff == difficultyID then
						-- wrap the npcGroup in the matching header if it is not a header
						if not npcGroup.headerID then
							npcGroup = app.CreateCustomHeader(headerID, {g={CreateObject(npcGroup)}})
						end
						-- app.PrintDebug("IsDrop.Diff",difficultyID,group.hash,"<==",npcGroup.hash)
						if groups then groups[#groups + 1] = CreateObject(npcGroup)
						else groups = { CreateObject(npcGroup) }; end
					end
				end
			end
		end
		return groups;
	else
		-- app.PrintDebug("FillNPC")
		local headerID, groups;
		for _,npcGroup in ipairs(npcGroups) do
			if npcGroup.hash ~= group.hash then
				headerID = GetRelativeFieldInSet(npcGroup, "headerID", NPCExpandHeaders);
				-- app.PrintDebug("DropCheck",app:SearchLink(npcGroup),"=>",headerID)
				-- where headerID is allowed
				if headerID then
					-- copy the header under the NPC groups
					-- wrap the npcGroup in the matching header if it is not a header
					if not npcGroup.headerID then
						npcGroup = app.CreateCustomHeader(headerID, {g={CreateObject(npcGroup)}})
					end
					-- app.PrintDebug("IsDrop",group.hash,"<==",npcGroup.hash)
					if groups then groups[#groups + 1] = CreateObject(npcGroup)
					else groups = { CreateObject(npcGroup) }; end
				end
			end
		end
		return groups;
	end
end
local function FillGroupDirect(group, FillData, doDGU)
	local ignoreSkip = group.sym or group.headerID or group.classID
	-- Determine Cost/Crafted/Symlink groups
	local groups = ArrayAppend({},
		DeterminePurchaseGroups(group, FillData),
		DetermineUpgradeGroups(group, FillData),
		DetermineCraftedGroups(group, FillData),
		DetermineNPCDrops(group, FillData),
		DetermineSymlinkGroups(group));

	-- Adding the groups normally based on available-source priority
	PriorityNestObjects(group, groups, nil, app.RecursiveCharacterRequirementsFilter, app.RecursiveGroupRequirementsFilter);

	if groups and #groups > 0 then
		-- if FillData.Debug then
		-- 	app.PrintDebug("FG-MergeResults",app:SearchLink(group),#groups,"=>",#group.g)
		-- end
		AssignChildren(group);
		if doDGU then app.DirectGroupUpdate(group); end
		-- check if this group is actually force-filled
		local forceFillType = not ignoreSkip and ForceFillDB[group.__type]
		if forceFillType and forceFillType[group.keyval] then
			ignoreSkip = true
		end
		-- mark this group as being filled since it actually received filled content (unless it's ignored for being skipped)
		if not ignoreSkip then
			local groupHash = group.hash;
			if groupHash then
				-- app.PrintDebug("FGA-Included",groupHash,#groups)
				FillData.Included[groupHash] = true;
			end
		end
	end
end
local function SkipFillingGroup(group, FillData)
	local skipFill = group.skipFill
	if (skipFill and FillData.InWindow) or skipFill == 2 then return true; end

	-- do not fill the same object twice in multiple Locations
	local groupHash, included = group.hash, FillData.Included;
	if included[groupHash] then return true; end

	-- do not fill 'saved' groups in ATT tooltips
	-- or groups directly under saved groups unless in Debug mode
	if not app.MODE_DEBUG then
		-- only ignored filling saved 'quest' groups (unless it's an Item, which we ignore the ignore... :D)
		if group.questID then
			if not group.itemID and group.saved then
				return true
			end
			-- don't fill under locked quests
			if group.locked then
				return true
			end
		end
		-- root fills of a thing from a saved parent should still show their contains, so don't use .parent
		local parent = rawget(group, "parent");
		-- direct parent is a saved quest, then do not fill with stuff
		if parent and parent.questID and (parent.saved or parent.locked) then return true; end
	end
end
-- Fills the group and returns an array of the next layer of groups to fill
local function FillGroupsLayered(group, FillData)
	if SkipFillingGroup(group, FillData) then
		-- if FillData.Debug then
		-- 	app.print(app.Modules.Color.Colorize("FGR-SKIP",app.Colors.ChatLinkError),app:SearchLink(group))
		-- end
		-- app.PrintDebug(Colorize("FGR-SKIP",app.Colors.ChatLinkError),app:SearchLink(group))
		return;
	end
	-- app.PrintDebug("FGR",group.hash)

	FillGroupDirect(group, FillData)

	return group.g
end
-- Fills the group and returns an array of the next layer of groups to fill
-- Run an entire layer, run a function to run the next layer
-- Capture next layer
local function FillGroupsLayeredAsync(group, FillData)
	if SkipFillingGroup(group, FillData) then
		-- if FillData.Debug then
		-- 	app.print(app.Modules.Color.Colorize("FGR-SKIP",app.Colors.ChatLinkError),app:SearchLink(group))
		-- end
		-- app.PrintDebug(Colorize("FGR-SKIP",app.Colors.ChatLinkError),app:SearchLink(group))
		return;
	end
	-- app.PrintDebug("FGL",group.hash)

	FillGroupDirect(group, FillData, true)

	local g = group.g;
	if g then
		-- if FillData.CurrentLayer then
		-- 	app.PrintDebug("AddLayered.g",FillData.CurrentLayer,#g,app:SearchLink(group))
		-- end
		app.ArrayAppend(FillData.NextLayer, g)
	end
end
local function RunGroupsLayeredAsync(FillData)
	local g = FillData.NextLayer;
	if #g > 0 then
		-- if FillData.CurrentLayer then
		-- 	app.PrintDebug("FillLayered",FillData.CurrentLayer,#g)
		-- 	FillData.CurrentLayer = FillData.CurrentLayer + 1
		-- end
		local Run = FillData.Runner.Run;
		-- Then nest anything further
		for _,o in ipairs(g) do
			Run(FillGroupsLayeredAsync, o, FillData)
		end
		wipe(FillData.NextLayer)
		-- Re-run the layer runner since there's been more filling scheduled
		Run(RunGroupsLayeredAsync, FillData)
	end
end
-- If we fill something under the group where it may be usable without itself meeting current filters,
-- then it should override filtering during UpdateGroup
local function AssignGroupFilledTag(group)
	group.wasFilled = group.filledReagent or group.filledCost or group.filledUpgrade
	-- app.PrintDebug("wasFilled",app:SearchLink(group),group.filledReagent,group.filledCost,group.filledUpgrade)
end
local function HandleOnWindowFillComplete(window)
	window.data._fillcomplete = true
	AssignGroupFilledTag(window.data)
	app.HandleEvent("OnWindowFillComplete", window)
end
-- Appends sub-groups into the item group based on what is required to have this item (cost, source sub-group, reagents, symlinks)
local FillGroups = function(group)
	group.__FillGroups = true
	-- Sometimes entire sub-groups should be preventing from even allowing filling (i.e. Dynamic groups)
	local skipFull = app.GetRelativeRawWithField(group, "skipFull");
	if skipFull then return end
	-- Check if this group is inside a Window or not
	local groupWindow = app.GetRelativeRawWithField(group, "window");
	-- Setup the FillData for this fill operation
	local FillData = {
		Included = {},
		CraftedItems = {},
		NextLayer = {},
		-- CurrentLayer = 0,	-- debugging
		InWindow = groupWindow and true or nil,
		NestNPCData = app.Settings:GetTooltipSetting("NPCData:Nested"),
		SkipLevel = app.GetSkipLevel(),
		Root = group,
		FillRecipes = group.recipeID or app.ReagentsDB[group.itemID or 0],
		-- Debug = group.itemID == 207026
	};

	-- app.PrintDebug("FillGroups",group.__type,group,app:SearchLink(group))
	-- app.PrintTable(FillData)

	-- Fill the group with all nestable content
	if groupWindow then
		local Runner = groupWindow:GetRunner();
		FillData.Runner = Runner
		if not groupWindow.SelfHandleOnWindowFillComplete then
			-- capture a function closure which can handle the event for the window
			-- since OnEnd does not handle parameters
			groupWindow.SelfHandleOnWindowFillComplete = function()
				HandleOnWindowFillComplete(groupWindow)
			end
		end
		-- only trigger the OnWindowFillComplete event if we are filling the Root group of the window
		if groupWindow.data == group then
			Runner.OnEnd(groupWindow.SelfHandleOnWindowFillComplete)
		end
		-- 1 is way too low as it then takes 1 frame per individual row in the minilist... i.e. Valdrakken took 14,000 frames
		Runner.SetPerFrame(25);
		-- Recursive Fill
		-- Runner.Run(FillGroupsRecursiveAsync, group, FillData);

		-- Layered Fill
		Runner.Run(FillGroupsLayeredAsync, group, FillData)
		Runner.Run(RunGroupsLayeredAsync, FillData)

	else
		-- app.PrintDebug("FG",group.hash)
		-- this performs depth-first filling which leads to usually one group having tons of nesting
		-- and other top-level groups being skipped as they had some other means of being
		-- filled in a deeper group
		-- FillGroupsRecursive(group, FillData);

		-- this logic performs fills across an entire logical layer of data via a breadth-first approach
		-- which should ideally have less nesting in total
		local FillLayer = {group}
		local NextLayer = {}
		while #FillLayer > 0 do
			for _,fillGroup in ipairs(FillLayer) do
				app.ArrayAppend(NextLayer, FillGroupsLayered(fillGroup, FillData))
			end
			FillLayer = NextLayer
			NextLayer = {}
		end

		AssignGroupFilledTag(group)
		-- app.PrintDebugPrior("FG",group.hash)
	end

	-- if app.Debugging then app.PrintTable(included) end
	-- app.PrintDebug("FillGroups Complete",group.hash,group.__type)
end
app.FillGroups = FillGroups
local function TryFillPopoutGroup(group)
	-- If the group specifically needs to be filled, do that now that it's in the window
	if not group.__FillGroups then
		-- app.PrintDebug("DoFillGroups",app:SearchLink(group))
		app.SetSkipLevel(2)
		FillGroups(group)
		app.SetSkipLevel(0)
	-- else app.PrintDebug("already filled",app:SearchLink(group))
	end
end
app.AddEventHandler("OnNewPopoutGroup", TryFillPopoutGroup)