-- CoaExporter / Collectors / MysticScrolls.lua
--
-- Async tooltip scraper for all known mystic enchant scrolls.
-- Iterates AE.ScrollCatalog (generated from AtlasLootAscension) and dumps
-- tooltip text + the spell taught by each scroll.
--
-- Usage: /coae scrolls scan    → start scan (one-time; dumps progress to chat)
--        /coae scrolls export  → print accumulated JSON of everything scanned
--        /coae scrolls reset   → clear cache
--
-- Design notes:
--   - WoW lazy-loads item data. First GetItemInfo() for an unseen item
--     returns nil and triggers a server query. We retry with delay.
--   - Results accumulate in CoaExporterScrollCache SavedVariable so a
--     single run across sessions builds up the full DB.
--   - A "scan" pass fires a batch of GetItemInfo requests, then waits,
--     then re-scans and records whatever resolved. Unresolved entries are
--     retried on the next scan.

CoaExporter = _G.CoaExporter or {}
_G.CoaExporter = CoaExporter
local AE = CoaExporter

CoaExporterScrollCache = CoaExporterScrollCache or {
    entries = {},
    meta = {
        lastScanAt = nil,
        totalCatalog = 0,
        resolved = 0,
        unresolved = {},
    },
}

local function EnsureScanner()
    if not AE._scrollScanner then
        AE._scrollScanner = CreateFrame("GameTooltip", "CoaExpScrollsTT", nil, "GameTooltipTemplate")
        AE._scrollScanner:SetOwner(WorldFrame, "ANCHOR_NONE")
    end
    return AE._scrollScanner
end

local function TipLines(tt)
    local out = {}
    for i = 1, tt:NumLines() do
        local left = _G[tt:GetName() .. "TextLeft" .. i]
        if left then
            local t = left:GetText()
            if t and t ~= "" then out[#out+1] = t end
        end
    end
    return out
end

local function ScanItemTooltip(itemID)
    local tt = EnsureScanner()
    tt:ClearLines()
    tt:SetHyperlink("item:" .. itemID)
    return TipLines(tt)
end

local function FlatCatalog()
    local out = {}
    if not AE.ScrollCatalog then return out end
    for class, list in pairs(AE.ScrollCatalog) do
        for _, e in ipairs(list) do
            out[#out+1] = { itemID = e.itemID, name = e.name, class = class }
        end
    end
    return out
end

local function TryResolve(entry)
    local cache = CoaExporterScrollCache.entries
    if cache[entry.itemID] and cache[entry.itemID].itemTooltip then
        return true
    end
    local name, _, quality = GetItemInfo(entry.itemID)
    if not name then
        GameTooltip:SetOwner(WorldFrame, "ANCHOR_NONE")
        GameTooltip:SetHyperlink("item:" .. entry.itemID)
        GameTooltip:Hide()
        return false
    end
    local itemLines = ScanItemTooltip(entry.itemID)
    local spellName, spellRank
    if GetItemSpell then
        spellName, spellRank = GetItemSpell(entry.itemID)
    end
    cache[entry.itemID] = {
        itemID = entry.itemID,
        class = entry.class,
        scrollName = entry.name,
        itemName = name,
        quality = quality,
        spellName = spellName,
        spellRank = spellRank,
        itemTooltip = table.concat(itemLines, "\n"),
        fetchedAt = time(),
    }
    return #itemLines > 0
end

function AE.ScrollsScanPass()
    local catalog = FlatCatalog()
    local total = #catalog
    CoaExporterScrollCache.meta.totalCatalog = total
    local newlyResolved = 0
    local unresolved = {}
    for _, entry in ipairs(catalog) do
        if TryResolve(entry) then
            newlyResolved = newlyResolved + 1
        else
            unresolved[#unresolved+1] = entry.itemID
        end
    end
    CoaExporterScrollCache.meta.lastScanAt = time()
    CoaExporterScrollCache.meta.resolved = newlyResolved
    CoaExporterScrollCache.meta.unresolved = unresolved
    return { total = total, resolved = newlyResolved, unresolved = #unresolved }
end

function AE.ScrollsStartScan(callback)
    local attempts = 0
    local maxAttempts = 4
    local function step()
        attempts = attempts + 1
        local stats = AE.ScrollsScanPass()
        DEFAULT_CHAT_FRAME:AddMessage(string.format(
            "CoaExporter scrolls: pass %d/%d - resolved %d/%d (still unresolved: %d)",
            attempts, maxAttempts, stats.resolved, stats.total, stats.unresolved))
        if stats.unresolved > 0 and attempts < maxAttempts then
            local t = CreateFrame("Frame")
            local elapsed = 0
            t:SetScript("OnUpdate", function(self, dt)
                elapsed = elapsed + dt
                if elapsed > 5 then
                    self:SetScript("OnUpdate", nil)
                    step()
                end
            end)
        else
            if callback then callback(stats) end
        end
    end
    step()
end

function AE.ScrollsExport()
    local out = {
        schemaVersion = 1,
        exportedAt = date("!%Y-%m-%dT%H:%M:%SZ"),
        catalogTotal = AE.ScrollCatalogTotal or 0,
        cacheMeta = CoaExporterScrollCache.meta,
        entries = {},
    }
    for _, rec in pairs(CoaExporterScrollCache.entries) do
        table.insert(out.entries, rec)
    end
    return out
end

function AE.ScrollsReset()
    CoaExporterScrollCache = {
        entries = {},
        meta = { lastScanAt = nil, totalCatalog = 0, resolved = 0, unresolved = {} },
    }
end

-- Compute total once on load (used in /coae catalog status etc.)
do
    local total = 0
    if AE.ScrollCatalog then
        for _, list in pairs(AE.ScrollCatalog) do
            total = total + #list
        end
    end
    AE.ScrollCatalogTotal = total
end

AE._loadedMysticScrolls = true