-- CoaExporter - Spellbook collector
--
-- Walks the player's spell book (BOOKTYPE_SPELL) tab by tab and emits
-- name + rank + spellID + icon for every learned spell. Pet book is
-- skipped — it's not part of the build/guide use-case.
--
-- 3.3.5 / Ascension API quirks handled defensively:
--   - GetSpellBookItemInfo(slot, "spell") returns (name, subName) on
--     vanilla 3.3.5 and (name, rank, [stuff]) on newer/private servers.
--     We treat the second return as a rank string regardless.
--   - GetSpellBookItemInfo doesn't return a spellID on 3.3.5. The reliable
--     way to get the ID is to parse it out of GetSpellLink(slot, "spell")
--     which yields "|cff71d5ff|Hspell:NNNN|h[Name]|h|r".
--   - Some entries can be category headers / flyouts; if no link or
--     spellID, we still record the name (it might be a known-spell that
--     just doesn't link, e.g. some passives).

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

local BOOKTYPE = (BOOKTYPE_SPELL or "spell")

local function safeCall(fn, ...)
    if type(fn) ~= "function" then return nil end
    local ok, a, b, c = pcall(fn, ...)
    if not ok then return nil end
    return a, b, c
end

local function spellIdFromLink(link)
    if not link or link == "" then return 0 end
    local id = string.match(link, "spell:(%d+)")
    return tonumber(id) or 0
end

local function iconPath(icon)
    if not icon or icon == "" then return "" end
    local p = icon:match("Interface\\Icons\\(.+)") or icon
    return tostring(p):lower()
end

function AE.CollectSpellbook()
    local out = { tabs = {}, totalSpells = 0 }

    if type(GetNumSpellTabs) ~= "function" then
        out.error = "GetNumSpellTabs not available"
        return out
    end

    local numTabs = GetNumSpellTabs() or 0
    for tabIndex = 1, numTabs do
        local tabName, tabTexture, offset, numSpells = safeCall(GetSpellTabInfo, tabIndex)
        offset = offset or 0
        numSpells = numSpells or 0

        local tab = {
            index    = tabIndex,
            name     = tabName or ("Tab " .. tabIndex),
            texture  = iconPath(tabTexture),
            offset   = offset,
            numSpells = numSpells,
            spells   = {},
        }

        for slot = offset + 1, offset + numSpells do
            local name, subOrRank = safeCall(GetSpellBookItemInfo, slot, BOOKTYPE)
            if (not name or name == "") and type(GetSpellName) == "function" then
                -- vanilla 3.3.5 fallback
                name, subOrRank = safeCall(GetSpellName, slot, BOOKTYPE)
            end

            local link = safeCall(GetSpellLink, slot, BOOKTYPE)
            local spellID = spellIdFromLink(link)

            local icon
            if spellID > 0 then
                local _, _, ic = GetSpellInfo(spellID)
                icon = ic
            end
            if (not icon) and type(GetSpellTexture) == "function" then
                icon = safeCall(GetSpellTexture, slot, BOOKTYPE)
            end

            if name and name ~= "" then
                table.insert(tab.spells, {
                    slot    = slot,
                    name    = name,
                    rank    = subOrRank or "",
                    spellID = spellID,
                    icon    = iconPath(icon),
                })
                out.totalSpells = out.totalSpells + 1
            end
        end

        table.insert(out.tabs, tab)
    end

    return out
end

AE._loadedSpellbook = true