-- AD Chain View (ren logik)
-- Rækkerne til fanen Kæder ud fra ADChain.last. Hver rod er foldet sammen som standard (én linje med samlet
-- status + antal forslag); foldet ud vises varerne rekursivt (kilde, behov pr. måned, status, lager). Forslag
-- vises altid (under roden eller under afgrøden). Pausede rødder (som modellen ikke længere ser som rødder)
-- får en grå linje med [Genoptag]. Nederst frie marker + antal automatiske skift (+ "marker scannes endnu"). Ingen spiladgang:
-- titleOf(navn) -> titel, fmt(liter) -> kompakt tal, textOf(l10n-nøgle) -> tekst gives udefra.
-- Manglende led (Task 10): foldet ud står problemteksten (problemText) som en rød tekstrække ("problem", ingen celler)
-- lige under varen — teksten er for lang til en celle og ombrydes af fanen.
-- Række: {kind="header"|"root"|"node"|"suggest"|"auto"|"info"|"empty"|"problem", indent, level, cells={c1..c5}, text,
--         actions={[celle]={kind="approve"|"dismiss"|"pause"|"resume", fieldId|rootKey}}, toggle=rootKey, fillType}

ADChainView = {}
ADChainView.INDENT = "  "
-- Tegnbudget pr. celle i flowListPrefab (gui/SmartPickupFrame.xml: textMaxWidth 192/162/62/244/92 px).
-- Antaget ~11,5 px pr. tegn (spuInfoText: 800 px ~ 70 tegn), fed ~12,5 px; c3 har kun tal (~10 px pr. tegn).
ADChainView.CELL_CHARS = {22, 20, 7, 28, 10} -- ca. tegn pr. celle (c1 192 px fed, c2 162, c3 62, c4 244, c5 92 fed)
ADChainView.MAX_SOURCE_NAMES = 2
-- Tegnbudget for en tekstlinje (addTextRow/spuInfoText: 800 px ~ 70 tegn), fx linjen med frie marker.
ADChainView.TEXT_ROW_CHARS = 70
-- "stramt": lager for en mark-afgrøde under så mange måneders behov -> gul
ADChainView.TIGHT_MONTHS = 3
-- nøgler rækkerne bruger (til l10n-testen)
ADChainView.TEXT_KEYS = {"spu_chain_finalFarm", "spu_chain_finalSell", "spu_chain_finalKeep", "spu_chain_suggestHeader", "spu_chain_empty", "spu_chain_approve", "spu_chain_dismiss", "spu_chain_auto",
    "spu_chain_flowOk", "spu_chain_flowMissing", "spu_chain_flowPallet", "spu_chain_flowNone", "spu_chain_flowStopped", "spu_chain_bottleneck",
    "spu_chain_buy", "spu_chain_cycle", "spu_chain_fieldShort", "spu_chain_tight", "spu_chain_noField", "spu_chain_buySource", "spu_chain_fromFields",
    "spu_chain_pause", "spu_chain_resume", "spu_chain_scanning", "spu_chain_rootOk", "spu_chain_rootError", "spu_chain_rootWaiting",
    "spu_chain_rootPaused", "spu_chain_rootSummary", "spu_chain_free", "spu_chain_switches", "spu_chain_gone", "spu_chain_col_item",
    "spu_chain_col_source", "spu_chain_col_perMonth", "spu_chain_col_status", "spu_chain_col_stock",
    "spu_chain_problem_buy", "spu_chain_problem_bottleneck", "spu_chain_problem_off", "spu_chain_problem_cycle", "spu_chain_problem_barn"}

local FLOW_KEYS = {ok = "spu_chain_flowOk", missing = "spu_chain_flowNone", stopped = "spu_chain_flowStopped", noVehicle = "spu_chain_flowMissing",
    pallet = "spu_chain_flowPallet"}
local ROOT_STATUS = {running = "spu_chain_rootOk", error = "spu_chain_rootError", waiting = "spu_chain_rootWaiting", stopped = "spu_chain_rootPaused"}

local function identity(value) return tostring(value) end

-- samme som SmartPickupFrame.formatCompact (standard-fmt når ingen gives, fx i beskeden fra kædens tick)
function ADChainView.compact(liters)
    liters = math.floor((liters or 0) + 0.5)
    if liters >= 1000000 then return string.format("%.1fM", liters / 1000000)
    elseif liters >= 1000 then return string.format("%.1fk", liters / 1000) end
    return string.format("%d", liters)
end

-- ---- UTF-8-sikker længde/afkortning (æøå og → er flere bytes) ----

function ADChainView.textLength(text)
    local count = 0
    for _ in tostring(text):gmatch("[^\128-\191]") do count = count + 1 end
    return count
end

local function utf8Prefix(text, chars)
    local result, count = {}, 0
    for char in text:gmatch("[^\128-\191][\128-\191]*") do
        if count >= chars then break end
        table.insert(result, char)
        count = count + 1
    end
    return table.concat(result)
end

-- Afkort til celle-budgettet med ".." til sidst.
function ADChainView.fit(text, chars)
    text = tostring(text or "")
    if ADChainView.textLength(text) <= chars then return text end
    return utf8Prefix(text, math.max(0, chars - 2)) .. ".."
end

local function fitCells(cells)
    local result = {}
    for index = 1, 5 do result[index] = ADChainView.fit(cells[index] or "", ADChainView.CELL_CHARS[index]) end
    return result
end

local function haText(ha)
    return string.format("%.0f", ha or 0)
end

local function plannedFruit(field)
    if field.targetFruit ~= nil and field.targetFruit ~= "" then return field.targetFruit end
    return field.fruit
end

local function edgeKey(node)
    return tostring(node.consumer) .. "|" .. tostring(node.fillType)
end

local function shortageByFruit(last)
    local result = {}
    for _, shortage in ipairs(last.shortages or {}) do result[shortage.fruit] = shortage end
    return result
end

local function stockOf(last, fruit)
    local stock = last.data ~= nil and last.data.stock or nil
    return stock ~= nil and fruit ~= nil and stock[fruit] or nil
end

-- Lager for en mark-node: afgrødens lager, eller varens eget lager for en markvare uden afgrøde (hø, hakkelse …).
local function fieldStockOf(last, node)
    if node.fruit ~= nil then return stockOf(last, node.fruit) end
    local byFill = last.data ~= nil and last.data.stockByFill or nil
    return byFill ~= nil and byFill[node.fillType] or nil
end

-- Mark-afgrøde uden mangel men med lager under TIGHT_MONTHS måneders behov.
local function isTight(node, last, short)
    if node.source ~= "field" or node.fruit == nil or short[node.fruit] ~= nil then return false end
    return (stockOf(last, node.fruit) or 0) < ADChainView.TIGHT_MONTHS * (node.perMonth or 0)
end

local function eachNode(nodes, fn, depth)
    for _, node in ipairs(nodes or {}) do
        fn(node, depth or 1)
        eachNode(node.children, fn, (depth or 1) + 1)
    end
end

function ADChainView.rootLevel(root, last)
    last = last or {}
    if (last.paused or {})[root.key] then return "stopped" end
    for _, problem in ipairs((last.chain or {}).problems or {}) do
        if problem.rootKey == root.key then return "error" end
    end
    local short, flowStatus = shortageByFruit(last), last.flowStatus or {}
    local hasShortage, hasWaiting = false, false
    eachNode(root.children, function(node)
        if node.fruit ~= nil and short[node.fruit] ~= nil then hasShortage = true end
        if (node.shortPerMonth or 0) > 0 then hasShortage = true end
        local status = node.consumer ~= nil and flowStatus[edgeKey(node)] or nil
        if (status ~= nil and status ~= "ok") or isTight(node, last, short) then hasWaiting = true end
    end)
    if hasShortage then return "error" end
    if hasWaiting then return "waiting" end
    return "running"
end

-- Højst MAX_SOURCE_NAMES navne + " +k".
local function joinCapped(names)
    local shown = {}
    for index = 1, math.min(#names, ADChainView.MAX_SOURCE_NAMES) do shown[index] = names[index] end
    local text = table.concat(shown, ", ")
    if #names > #shown then text = text .. " +" .. tostring(#names - #shown) end
    return text
end

-- Opskrifter (alle, også slukkede) der laver varen, i datarækkefølge.
local function producersOf(last, fillType)
    local list = {}
    for _, recipe in ipairs(last.data ~= nil and last.data.recipes or {}) do
        if ((recipe.outputs or {})[fillType] or 0) > 0 then table.insert(list, recipe) end
    end
    return list
end

-- Årsag i klart sprog med råd for et problem fra kædemodellen ({kind="buy"|"bottleneck"|"cycle", fillType, rootKey,
-- detail = manglende l/md, need = behov l/md}). Køb af en rest efter gårdens stalde -> stald-tekst. En producent spilleren selv har slukket (last.userOff, stadig
-- slukket) slår igennem som "slukket af dig" — det er den reelle årsag, uanset om modellen så køb eller flaskehals.
function ADChainView.problemText(problem, last, textOf, titleOf, fmt)
    last, textOf, fmt = last or {}, textOf or identity, fmt or ADChainView.compact
    titleOf = titleOf or function(name) return (last.titles or {})[name] or tostring(name) end
    local item = titleOf(problem.fillType)
    if problem.kind == "cycle" then return string.format(textOf("spu_chain_problem_cycle"), item) end
    local userOff, names, seen = last.userOff or {}, {}, {}
    for _, recipe in ipairs(producersOf(last, problem.fillType)) do
        if userOff[recipe.key] and not recipe.enabled then
            return string.format(textOf("spu_chain_problem_off"), tostring(recipe.buildingName), titleOf(recipe.name))
        end
        local name = tostring(recipe.buildingName)
        if (recipe.cyclesPerMonth or 0) > 0 and not seen[name] then
            seen[name] = true
            table.insert(names, name)
        end
    end
    if problem.kind == "bottleneck" and #names > 0 then
        local need = problem.need or problem.detail or 0
        local made = math.max(0, need - (problem.detail or 0))
        return string.format(textOf("spu_chain_problem_bottleneck"), joinCapped(names), fmt(math.floor(made + 0.5)), fmt(math.floor(need + 0.5)))
    end
    -- modellen melder også "køb" for resten, når gårdens stalde leverer for lidt: så er rådet ikke "byg en fabrik"
    for _, herd in ipairs(last.data ~= nil and last.data.husbandry or {}) do
        if ((herd.outputs or {})[problem.fillType] or 0) > 0 then
            return string.format(textOf("spu_chain_problem_barn"), item)
        end
    end
    return string.format(textOf("spu_chain_problem_buy"), item)
end

local function sourceText(node, last, textOf)
    local names = {}
    if node.source == "production" then
        for _, producer in ipairs(node.producers or {}) do table.insert(names, tostring(producer.buildingName)) end
    elseif node.source == "husbandry" then
        for _, herd in ipairs(node.herds or {}) do table.insert(names, tostring(herd.buildingName)) end
    elseif node.source == "field" then
        -- markvare uden egen afgrøde (hø, hakkelse …): ingen afgrødeplan, bare "fra marker"
        if node.fruit == nil then return textOf("spu_chain_fromFields") end
        for _, field in ipairs(last.fields or {}) do
            if plannedFruit(field) == node.fruit then table.insert(names, "F" .. tostring(field.id)) end
        end
        if #names == 0 then return textOf("spu_chain_noField") end
    elseif node.source == "buy" then
        return textOf("spu_chain_buySource")
    else
        return "-"
    end
    return joinCapped(names)
end

-- Nodens status (tekst, niveau): kredsløb/flaskehals/køb/mangel (rød) > flow ikke ok (gul) > stramt lager (gul) > flow ok.
local function nodeStatus(node, last, fmt, textOf, short)
    if node.source == "cycle" then return textOf("spu_chain_cycle"), "error" end
    if (node.shortPerMonth or 0) > 0 then
        local key = node.source == "production" and "spu_chain_bottleneck" or "spu_chain_buy"
        return string.format(textOf(key), fmt(node.shortPerMonth)), "error"
    end
    local shortage = node.fruit ~= nil and short[node.fruit] or nil
    if shortage ~= nil then return string.format(textOf("spu_chain_fieldShort"), haText(shortage.missingHa)), "error" end
    local status = node.consumer ~= nil and (last.flowStatus or {})[edgeKey(node)] or nil
    if status ~= nil and status ~= "ok" then return textOf(FLOW_KEYS[status] or "spu_chain_flowNone"), "waiting" end
    if isTight(node, last, short) then return textOf("spu_chain_tight"), "waiting" end
    if status == "ok" then return textOf("spu_chain_flowOk"), "running" end
    return "", "running"
end

local function joinText(cells)
    local parts = {}
    for _, cell in ipairs(cells) do
        if cell ~= nil and cell ~= "" then table.insert(parts, cell) end
    end
    return table.concat(parts, " · ")
end

local function makeRow(kind, indent, level, cells, actions, toggle)
    local fitted = fitCells(cells)
    return {kind = kind, indent = indent, level = level, cells = fitted, actions = actions or {}, toggle = toggle, text = joinText(fitted)}
end

local function suggestRow(action, indent, titleOf, textOf)
    local pad = string.rep(ADChainView.INDENT, indent)
    local from = (action.from ~= nil and action.from ~= "") and titleOf(action.from) or "-"
    local cells = {pad .. "F" .. tostring(action.fieldId) .. " " .. from, "→ " .. titleOf(action.to), haText(action.hectares) .. " ha"}
    if action.mode == "suggest" then
        cells[4], cells[5] = textOf("spu_chain_approve"), textOf("spu_chain_dismiss")
        return makeRow("suggest", indent, "waiting", cells,
            {[4] = {kind = "approve", fieldId = action.fieldId}, [5] = {kind = "dismiss", fieldId = action.fieldId}})
    end
    cells[4] = textOf("spu_chain_auto")
    return makeRow("auto", indent, "running", cells)
end

-- Handlinger for de afgrøder (i rækkefølge) der hentes fra mark under roden.
local function rootFruits(root)
    local fruits, seen = {}, {}
    eachNode(root.children, function(node)
        if node.source == "field" and node.fruit ~= nil and not seen[node.fruit] then
            seen[node.fruit] = true
            table.insert(fruits, node.fruit)
        end
    end)
    return fruits
end

local function actionsFor(last, fruit, modes)
    local list = {}
    for _, action in ipairs(last.actions or {}) do
        if action.to == fruit and modes[action.mode] then table.insert(list, action) end
    end
    return list
end

-- Alle forslag (mode "suggest") én gang pr. mark, efter marknummer (in-game 30/9: samme forslag stod under
-- hver kæde der bruger afgrøden, spredt mellem kæderne).
function ADChainView.suggestionList(last)
    local byField, list = {}, {}
    for _, action in ipairs((last or {}).actions or {}) do
        if action.mode == "suggest" and action.fieldId ~= nil and not byField[action.fieldId] then
            byField[action.fieldId] = true
            table.insert(list, action)
        end
    end
    table.sort(list, function(a, b) return (tonumber(a.fieldId) or 0) < (tonumber(b.fieldId) or 0) end)
    return list
end

-- Kæder efter status (fejl/mangel, venter, dækket, pause), så bygning, så produkt.
local LEVEL_RANK = {error = 1, waiting = 2, running = 3, stopped = 4}
function ADChainView.sortRoots(roots, last)
    local keyed = {}
    for index, root in ipairs(roots or {}) do
        table.insert(keyed, {root = root, rank = LEVEL_RANK[ADChainView.rootLevel(root, last)] or 5,
            building = tostring(root.buildingName or ""), name = tostring(root.name or ""), index = index})
    end
    table.sort(keyed, function(a, b)
        if a.rank ~= b.rank then return a.rank < b.rank end
        if a.building ~= b.building then return a.building < b.building end
        if a.name ~= b.name then return a.name < b.name end
        return a.index < b.index
    end)
    local sorted = {}
    for _, item in ipairs(keyed) do table.insert(sorted, item.root) end
    return sorted
end

local function rootRows(rows, root, last, ctx, isExpanded)
    local level = ADChainView.rootLevel(root, last)
    local paused = (last.paused or {})[root.key] == true
    local suggestions = {}
    for _, fruit in ipairs(rootFruits(root)) do
        for _, action in ipairs(actionsFor(last, fruit, {suggest = true})) do table.insert(suggestions, action) end
    end
    local status = ctx.textOf(ROOT_STATUS[level])
    if #suggestions > 0 then status = string.format(ctx.textOf("spu_chain_rootSummary"), status, #suggestions) end
    local marker = (#(root.children or {}) > 0) and (isExpanded and "– " or "+ ") or ""
    -- slutproduktet: "Sælg straks" (standard) eller "Behold" — klik på feltet skifter
    -- varer gården selv bruger (last.sellable uden roden) sælges aldrig: "Gård" uden klik
    local keep = (last.finalKeep or {})[root.key] == true
    local sellable = last.sellable == nil or last.sellable[root.key] == true
    local finalText = not sellable and "spu_chain_finalFarm" or (keep and "spu_chain_finalKeep" or "spu_chain_finalSell")
    local actions = {[5] = {kind = paused and "resume" or "pause", rootKey = root.key}}
    if sellable then actions[3] = {kind = "finalMode", rootKey = root.key, keep = not keep} end
    table.insert(rows, makeRow("root", 0, level, {marker .. ctx.titleOf(root.name), tostring(root.buildingName or ""),
        ctx.textOf(finalText), status, ctx.textOf(paused and "spu_chain_resume" or "spu_chain_pause")}, actions, root.key))
    if not isExpanded then return end
    local shown, problems, told = {}, {}, {}
    for _, problem in ipairs((last.chain or {}).problems or {}) do
        if problem.rootKey == root.key then table.insert(problems, problem) end
    end
    local function problemRows(fillType, indent)
        for _, problem in ipairs(problems) do
            local key = tostring(problem.fillType) .. "|" .. tostring(problem.kind)
            if (fillType == nil or problem.fillType == fillType) and not told[key] then
                told[key] = true
                table.insert(rows, {kind = "problem", indent = indent, level = "error",
                    text = string.rep(ADChainView.INDENT, indent) .. ADChainView.problemText(problem, last, ctx.textOf, ctx.titleOf, ctx.fmt)})
            end
        end
    end
    eachNode(root.children, function(node, depth)
        local text, nodeLevel = nodeStatus(node, last, ctx.fmt, ctx.textOf, ctx.short)
        local stock = node.source == "field" and fieldStockOf(last, node) or nil
        local row = makeRow("node", depth, nodeLevel, {string.rep(ADChainView.INDENT, depth) .. ctx.titleOf(node.fillType),
            sourceText(node, last, ctx.textOf), ctx.fmt(node.perMonth or 0), text, stock ~= nil and ctx.fmt(stock) or ""})
        row.fillType = node.fillType
        table.insert(rows, row)
        problemRows(node.fillType, depth + 1)
        if node.source == "field" and node.fruit ~= nil and not shown[node.fruit] then
            shown[node.fruit] = true
            for _, action in ipairs(actionsFor(last, node.fruit, {auto = true})) do
                table.insert(rows, suggestRow(action, depth + 1, ctx.titleOf, ctx.textOf))
            end
        end
    end)
    -- problemer uden en vist vare (bør ikke ske) står sidst under roden
    problemRows(nil, 1)
end

-- Pausede rødder: modelRecipes markerer dem paused, så modellen ser dem ikke som rødder -> grå linje med [Genoptag].
local function pausedRows(rows, last, ctx)
    local present, keys = {}, {}
    for _, root in ipairs(last.chain ~= nil and last.chain.roots or {}) do present[root.key] = true end
    for key in pairs(last.paused or {}) do
        if not present[key] then table.insert(keys, key) end
    end
    table.sort(keys, function(a, b) return tostring(a) < tostring(b) end)
    for _, key in ipairs(keys) do
        local recipe
        for _, candidate in ipairs(last.data ~= nil and last.data.recipes or {}) do
            if candidate.key == key then recipe = candidate end
        end
        local name = recipe ~= nil and recipe.name ~= nil and ctx.titleOf(recipe.name) or tostring(key)
        table.insert(rows, makeRow("root", 0, "stopped", {name, recipe ~= nil and tostring(recipe.buildingName or "") or "", "",
            ctx.textOf("spu_chain_rootPaused"), ctx.textOf("spu_chain_resume")}, {[5] = {kind = "resume", rootKey = key}}))
    end
    return #keys
end

-- "Marker fri til kæden: F1, F2 +k" — så mange navne som tekstlinjen kan rumme, resten talt.
function ADChainView.freeText(names, textOf)
    local format = textOf("spu_chain_free")
    if #names == 0 then return string.format(format, "-") end
    for count = #names, 1, -1 do
        local shown = {}
        for index = 1, count do shown[index] = names[index] end
        local list = table.concat(shown, ", ")
        if count < #names then list = list .. " +" .. tostring(#names - count) end
        local text = string.format(format, list)
        if ADChainView.textLength(text) <= ADChainView.TEXT_ROW_CHARS then return text end
    end
    return ADChainView.fit(string.format(format, "+" .. tostring(#names)), ADChainView.TEXT_ROW_CHARS)
end

local function footerRows(rows, last, textOf)
    local free = {}
    for _, field in ipairs(last.fields or {}) do
        if field.chainFree then table.insert(free, field.id) end
    end
    table.sort(free)
    local names = {}
    for _, id in ipairs(free) do table.insert(names, "F" .. tostring(id)) end
    table.insert(rows, {kind = "info", indent = 0, text = ADChainView.freeText(names, textOf)})
    table.insert(rows, {kind = "info", indent = 0, text = string.format(textOf("spu_chain_switches"), last.switchCount or 0)})
    if last.fieldsIncomplete then table.insert(rows, {kind = "info", indent = 0, text = textOf("spu_chain_scanning")}) end
end

-- expanded = {[rodnøgle] = true} for udfoldede rødder (alle andre er foldet sammen).
function ADChainView.rows(last, titleOf, fmt, textOf, expanded)
    textOf, fmt, expanded = textOf or identity, fmt or identity, expanded or {}
    local titles = last ~= nil and last.titles or {}
    titleOf = titleOf or function(name) return (titles or {})[name] or tostring(name) end
    local rows = {}
    local roots = last ~= nil and last.chain ~= nil and last.chain.roots or {}
    local hasPaused = last ~= nil and next(last.paused or {}) ~= nil
    if #roots == 0 and not hasPaused then
        table.insert(rows, {kind = "empty", indent = 0, text = textOf("spu_chain_empty")})
    end
    if last == nil then return rows end
    if #roots > 0 or hasPaused then
        table.insert(rows, makeRow("header", 0, nil, {textOf("spu_chain_col_item"), textOf("spu_chain_col_source"),
            textOf("spu_chain_col_perMonth"), textOf("spu_chain_col_status"), textOf("spu_chain_col_stock")}))
    end
    local ctx = {titleOf = titleOf, fmt = fmt, textOf = textOf, short = shortageByFruit(last)}
    local suggestions = ADChainView.suggestionList(last)
    if #suggestions > 0 then
        table.insert(rows, {kind = "info", indent = 0, text = textOf("spu_chain_suggestHeader")})
        for _, action in ipairs(suggestions) do table.insert(rows, suggestRow(action, 0, titleOf, textOf)) end
    end
    for _, root in ipairs(ADChainView.sortRoots(roots, last)) do rootRows(rows, root, last, ctx, expanded[root.key] == true) end
    pausedRows(rows, last, ctx)
    footerRows(rows, last, textOf)
    return rows
end