-- Memory Profiler for CC:Tweaked / Opus OS
-- Usage: memprofile [--watch] [--interval <seconds>]
--
-- Shows current Lua memory usage with breakdown estimates.
-- Use --watch to continuously monitor.
-- Useful for detecting memory leaks and understanding overhead.

local args = { ... }
local watch = false
local interval = 3

for i, arg in ipairs(args) do
    if arg == '--watch' or arg == '-w' then
        watch = true
    elseif arg == '--interval' or arg == '-i' then
        interval = tonumber(args[i + 1]) or 3
    elseif arg == '--help' or arg == '-h' then
        print('Usage: memprofile [--watch] [--interval <secs>]')
        print('')
        print('Options:')
        print('  --watch, -w       Continuously monitor memory')
        print('  --interval, -i N  Update interval in seconds (default: 3)')
        print('  --help, -h        Show this help')
        return
    end
end

local term = _G.term
local os = _G.os

local function formatBytes(bytes)
    if bytes < 1024 then
        return string.format('%d B', bytes)
    elseif bytes < 1024 * 1024 then
        return string.format('%.1f KB', bytes / 1024)
    else
        return string.format('%.2f MB', bytes / (1024 * 1024))
    end
end

local function countTable(t, seen)
    if type(t) ~= 'table' or seen[t] then return 0, 0 end
    seen[t] = true
    local entries = 0
    local nested = 0
    for k, v in pairs(t) do
        entries = entries + 1
        if type(v) == 'table' then
            local e, n = countTable(v, seen)
            nested = nested + 1 + e
            entries = entries + n
        end
        if type(k) == 'table' then
            local e, n = countTable(k, seen)
            nested = nested + 1 + e
            entries = entries + n
        end
    end
    return entries, nested
end

local function getSnapshot()
    -- Force a full GC cycle to get accurate usage
    collectgarbage('collect')
    collectgarbage('collect')
    local memKB = collectgarbage('count')  -- returns KB as float

    local snapshot = {
        totalKB = memKB,
        totalBytes = math.floor(memKB * 1024),
        timestamp = os.clock(),
    }

    -- Count entries in major global tables
    local seen = {}
    local globals = {}

    local interesting = {
        { name = '_G (globals)',  tbl = _G },
        { name = 'kernel',       tbl = _G.kernel },
        { name = 'network',      tbl = _G.network },
        { name = 'device',       tbl = _G.device },
    }

    for _, item in ipairs(interesting) do
        if type(item.tbl) == 'table' then
            local entries, nested = countTable(item.tbl, seen)
            table.insert(globals, {
                name = item.name,
                entries = entries,
                nested = nested,
            })
        end
    end

    snapshot.globals = globals

    -- Count routines if kernel is available
    if _G.kernel and _G.kernel.routines then
        snapshot.routines = #_G.kernel.routines
    end

    -- Count loaded modules
    if package and package.loaded then
        local count = 0
        for _ in pairs(package.loaded) do
            count = count + 1
        end
        snapshot.loadedModules = count
    end

    return snapshot
end

local function printSnapshot(snap, prev)
    term.clear()
    term.setCursorPos(1, 1)

    local w = term.getSize()
    local sep = string.rep('-', w)

    term.setTextColor(colors.yellow)
    print('=== Memory Profile ===')
    term.setTextColor(colors.white)
    print('')

    -- Total memory
    local memStr = formatBytes(snap.totalBytes)
    local deltaStr = ''
    if prev then
        local delta = snap.totalBytes - prev.totalBytes
        if delta > 0 then
            deltaStr = string.format('  (+%s)', formatBytes(delta))
            term.setTextColor(colors.red)
        elseif delta < 0 then
            deltaStr = string.format('  (-%s)', formatBytes(-delta))
            term.setTextColor(colors.green)
        end
    end
    term.setTextColor(colors.white)
    print(string.format('Total Memory: %s%s', memStr, deltaStr))
    print(string.format('Uptime:       %.1fs', snap.timestamp))
    print('')

    -- Table sizes
    term.setTextColor(colors.lightBlue)
    print('Global Tables:')
    term.setTextColor(colors.white)
    print(sep)
    print(string.format('  %-20s  %8s  %8s', 'Name', 'Entries', 'Nested'))
    print(sep)
    for _, g in ipairs(snap.globals) do
        print(string.format('  %-20s  %8d  %8d', g.name, g.entries, g.nested))
    end
    print(sep)
    print('')

    -- Kernel info
    if snap.routines then
        term.setTextColor(colors.lightBlue)
        print('Kernel:')
        term.setTextColor(colors.white)
        print(string.format('  Active routines: %d', snap.routines))
    end

    if snap.loadedModules then
        print(string.format('  Loaded modules:  %d', snap.loadedModules))
    end

    print('')

    -- CC:Tweaked limits
    term.setTextColor(colors.gray)
    print('Note: CC:Tweaked default memory limit is ~128MB per computer.')
    print('High memory usage may cause slowdowns or crashes.')

    if watch then
        print('')
        term.setTextColor(colors.yellow)
        print(string.format('Refreshing every %ds... (Ctrl+T to stop)', interval))
    end
end

local function run()
    local prev = nil

    if watch then
        while true do
            local snap = getSnapshot()
            printSnapshot(snap, prev)
            prev = snap
            os.sleep(interval)
        end
    else
        local snap = getSnapshot()
        printSnapshot(snap, nil)
    end
end

run()