fix: implement reliable modem command delivery with acknowledgment and retry mechanism

inventoryManager.lua

@@ -708,6 +708,13 @@ local function main()
                                 state.needsRedraw = true
                                 state.smelterNeedsRedraw = true
                                 pcall(broadcastState)
+                                pcall(function()
+                                    ctx.networkModem.transmit(replyChannel, cfg.ORDER_CHANNEL, {
+                                        type      = "command_ack",
+                                        commandId = message.commandId,
+                                        success   = true,
+                                    })
+                                end)
 
                             elseif message.type == "toggle_pause" then
                                 state.smeltingPaused = not state.smeltingPaused
@@ -717,6 +724,13 @@ local function main()
                                 state.smelterNeedsRedraw = true
                                 state.needsRedraw = true
                                 pcall(broadcastState)
+                                pcall(function()
+                                    ctx.networkModem.transmit(replyChannel, cfg.ORDER_CHANNEL, {
+                                        type      = "command_ack",
+                                        commandId = message.commandId,
+                                        success   = true,
+                                    })
+                                end)
 
                             elseif message.type == "toggle_recipe" and message.recipe then
                                 if state.disabledRecipes[message.recipe] then
@@ -730,6 +744,13 @@ local function main()
                                 state.bumpStateVersion()
                                 state.smelterNeedsRedraw = true
                                 pcall(broadcastState)
+                                pcall(function()
+                                    ctx.networkModem.transmit(replyChannel, cfg.ORDER_CHANNEL, {
+                                        type      = "command_ack",
+                                        commandId = message.commandId,
+                                        success   = true,
+                                    })
+                                end)
 
                             elseif message.type == "enable_all" then
                                 state.disabledRecipes = {}
@@ -739,6 +760,13 @@ local function main()
                                 state.bumpStateVersion()
                                 state.smelterNeedsRedraw = true
                                 pcall(broadcastState)
+                                pcall(function()
+                                    ctx.networkModem.transmit(replyChannel, cfg.ORDER_CHANNEL, {
+                                        type      = "command_ack",
+                                        commandId = message.commandId,
+                                        success   = true,
+                                    })
+                                end)
 
                             elseif message.type == "disable_all" then
                                 for inputName in pairs(cfg.SMELTABLE) do
@@ -750,11 +778,25 @@ local function main()
                                 state.bumpStateVersion()
                                 state.smelterNeedsRedraw = true
                                 pcall(broadcastState)
+                                pcall(function()
+                                    ctx.networkModem.transmit(replyChannel, cfg.ORDER_CHANNEL, {
+                                        type      = "command_ack",
+                                        commandId = message.commandId,
+                                        success   = true,
+                                    })
+                                end)
 
                             elseif message.type == "sort_barrel" and message.barrelName then
                                 log.info("NET", "Sort barrel: %s", message.barrelName)
                                 pcall(ops.sortBarrel, message.barrelName)
                                 pcall(broadcastState)
+                                pcall(function()
+                                    ctx.networkModem.transmit(replyChannel, cfg.ORDER_CHANNEL, {
+                                        type      = "command_ack",
+                                        commandId = message.commandId,
+                                        success   = true,
+                                    })
+                                end)
 
                             elseif message.type == "register_droppers" and message.clientId and message.droppers then
                                 local cid = tostring(message.clientId)
@@ -847,6 +889,13 @@ local function main()
                                 state.smelterNeedsRedraw = true
                                 state.needsRedraw = true
                                 pcall(broadcastState)
+                                pcall(function()
+                                    ctx.networkModem.transmit(replyChannel, cfg.ORDER_CHANNEL, {
+                                        type      = "command_ack",
+                                        commandId = message.commandId,
+                                        success   = true,
+                                    })
+                                end)
 
                             elseif message.type == "learn_crafting_recipe" and message.output and message.count and message.grid then
                                 cfg.recipeBook.learnCraftingRecipe(message.output, message.count, message.grid)
@@ -856,6 +905,13 @@ local function main()
                                 state.configDirty = true
                                 state.bumpStateVersion()
                                 pcall(broadcastState)
+                                pcall(function()
+                                    ctx.networkModem.transmit(replyChannel, cfg.ORDER_CHANNEL, {
+                                        type      = "command_ack",
+                                        commandId = message.commandId,
+                                        success   = true,
+                                    })
+                                end)
 
                             elseif message.type == "learn_smelting_recipe" and message.input and message.result then
                                 cfg.recipeBook.learnSmeltingRecipe(message.input, message.result, message.furnaces)
@@ -865,6 +921,13 @@ local function main()
                                 state.configDirty = true
                                 state.bumpStateVersion()
                                 pcall(broadcastState)
+                                pcall(function()
+                                    ctx.networkModem.transmit(replyChannel, cfg.ORDER_CHANNEL, {
+                                        type      = "command_ack",
+                                        commandId = message.commandId,
+                                        success   = true,
+                                    })
+                                end)
 
                             elseif message.type == "forget_recipe" and message.recipe then
                                 local forgot = cfg.recipeBook.forgetCraftingRecipe(message.recipe) or
@@ -877,6 +940,13 @@ local function main()
                                     state.bumpStateVersion()
                                 end
                                 pcall(broadcastState)
+                                pcall(function()
+                                    ctx.networkModem.transmit(replyChannel, cfg.ORDER_CHANNEL, {
+                                        type      = "command_ack",
+                                        commandId = message.commandId,
+                                        success   = true,
+                                    })
+                                end)
 
                             elseif message.type == "find_item" and message.items then
                                 -- Return chest+slot locations for the first matching item

inventoryWebBridge.lua

@@ -62,6 +62,14 @@ local running = true
 local ws = nil            -- active WebSocket handle (nil when not connected)
 local wsConnected = false -- gates WS vs HTTP transport selection
 
+-- Reliable modem delivery: pending commands awaiting manager acknowledgment.
+-- processCommand() inserts here; modemListener removes on result receipt.
+-- A retry task periodically re-transmits unacknowledged commands.
+local pendingModem = {}     -- commandId -> { payload, channel, replyChannel, sent, retries }
+local MODEM_RETRY_INTERVAL = 2   -- seconds between retry sweeps
+local MODEM_RETRY_MAX      = 5   -- max retransmissions before giving up
+local MODEM_RETRY_DELAY    = 2   -- seconds before first retry (per command)
+
 -------------------------------------------------
 -- HTTP helpers (thin wrappers around platform)
 -------------------------------------------------
@@ -134,96 +142,55 @@ local function processCommand(cmd)
 
     print(string.format("[CMD] %s", action))
 
+    -- Build the modem payload from the server command
+    local payload
     if action == "order" then
-        modem.transmit(ORDER_CHANNEL, BRIDGE_REPLY_CHANNEL, {
+        payload = {
             type        = "order",
             commandId   = cmd.commandId,
             itemName    = cmd.itemName,
             amount      = cmd.amount,
             dropperName = cmd.dropperName,
-        })
+        }
     elseif action == "scan" then
-        modem.transmit(ORDER_CHANNEL, BRIDGE_REPLY_CHANNEL, {
+        payload = { type = "scan", commandId = cmd.commandId }
-            type      = "scan",
-            commandId = cmd.commandId,
-        })
     elseif action == "toggle_pause" then
-        modem.transmit(ORDER_CHANNEL, BRIDGE_REPLY_CHANNEL, {
+        payload = { type = "toggle_pause", commandId = cmd.commandId }
-            type      = "toggle_pause",
-            commandId = cmd.commandId,
-        })
     elseif action == "toggle_recipe" then
-        modem.transmit(ORDER_CHANNEL, BRIDGE_REPLY_CHANNEL, {
+        payload = { type = "toggle_recipe", commandId = cmd.commandId, recipe = cmd.recipe }
-            type      = "toggle_recipe",
-            commandId = cmd.commandId,
-            recipe    = cmd.recipe,
-        })
     elseif action == "enable_all" then
-        modem.transmit(ORDER_CHANNEL, BRIDGE_REPLY_CHANNEL, {
+        payload = { type = "enable_all", commandId = cmd.commandId }
-            type      = "enable_all",
-            commandId = cmd.commandId,
-        })
     elseif action == "disable_all" then
-        modem.transmit(ORDER_CHANNEL, BRIDGE_REPLY_CHANNEL, {
+        payload = { type = "disable_all", commandId = cmd.commandId }
-            type      = "disable_all",
-            commandId = cmd.commandId,
-        })
     elseif action == "sort_barrel" then
-        modem.transmit(ORDER_CHANNEL, BRIDGE_REPLY_CHANNEL, {
+        payload = { type = "sort_barrel", commandId = cmd.commandId, barrelName = cmd.barrelName }
-            type       = "sort_barrel",
-            commandId  = cmd.commandId,
-            barrelName = cmd.barrelName,
-        })
     elseif action == "craft" then
-        modem.transmit(ORDER_CHANNEL, BRIDGE_REPLY_CHANNEL, {
+        payload = { type = "craft", commandId = cmd.commandId, recipeIdx = cmd.recipeIdx }
-            type      = "craft",
-            commandId = cmd.commandId,
-            recipeIdx = cmd.recipeIdx,
-        })
     elseif action == "recursive_craft" then
-        modem.transmit(ORDER_CHANNEL, BRIDGE_REPLY_CHANNEL, {
+        payload = { type = "recursive_craft", commandId = cmd.commandId, itemName = cmd.itemName, count = cmd.count }
-            type      = "recursive_craft",
-            commandId = cmd.commandId,
-            itemName  = cmd.itemName,
-            count     = cmd.count,
-        })
     elseif action == "learn_crafting_recipe" then
-        modem.transmit(ORDER_CHANNEL, BRIDGE_REPLY_CHANNEL, {
+        payload = { type = "learn_crafting_recipe", commandId = cmd.commandId, output = cmd.output, count = cmd.count, grid = cmd.grid }
-            type      = "learn_crafting_recipe",
-            commandId = cmd.commandId,
-            output    = cmd.output,
-            count     = cmd.count,
-            grid      = cmd.grid,
-        })
     elseif action == "learn_smelting_recipe" then
-        modem.transmit(ORDER_CHANNEL, BRIDGE_REPLY_CHANNEL, {
+        payload = { type = "learn_smelting_recipe", commandId = cmd.commandId, input = cmd.input, result = cmd.result, furnaces = cmd.furnaces }
-            type      = "learn_smelting_recipe",
-            commandId = cmd.commandId,
-            input     = cmd.input,
-            result    = cmd.result,
-            furnaces  = cmd.furnaces,
-        })
     elseif action == "forget_recipe" then
-        modem.transmit(ORDER_CHANNEL, BRIDGE_REPLY_CHANNEL, {
+        payload = { type = "forget_recipe", commandId = cmd.commandId, recipe = cmd.recipe }
-            type      = "forget_recipe",
-            commandId = cmd.commandId,
-            recipe    = cmd.recipe,
-        })
     elseif action == "sync_disabled_recipes" then
-        modem.transmit(ORDER_CHANNEL, BRIDGE_REPLY_CHANNEL, {
+        payload = { type = "sync_disabled_recipes", commandId = cmd.commandId, disabledRecipes = cmd.disabledRecipes, smeltingPaused = cmd.smeltingPaused }
-            type             = "sync_disabled_recipes",
-            commandId        = cmd.commandId,
-            disabledRecipes  = cmd.disabledRecipes,
-            smeltingPaused   = cmd.smeltingPaused,
-        })
     elseif action == "reboot" then
-        modem.transmit(ORDER_CHANNEL, BRIDGE_REPLY_CHANNEL, {
+        payload = { type = "reboot", commandId = cmd.commandId, target = cmd.target or "all" }
-            type      = "reboot",
-            commandId = cmd.commandId,
-            target    = cmd.target or "all",
-        })
     else
         print("[CMD] Unknown action: " .. tostring(action))
+        return
+    end
+
+    -- Transmit and track for reliable delivery
+    modem.transmit(ORDER_CHANNEL, BRIDGE_REPLY_CHANNEL, payload)
+    if payload.commandId then
+        pendingModem[payload.commandId] = {
+            payload      = payload,
+            sent         = os.clock(),
+            retries      = 0,
+        }
     end
 end
 
@@ -240,6 +207,10 @@ local function modemListener()
                 latestState = message
             end
         elseif channel == BRIDGE_REPLY_CHANNEL and type(message) == "table" then
+            -- Clear pending retry on any response matching a commandId
+            if message.commandId and pendingModem[message.commandId] then
+                pendingModem[message.commandId] = nil
+            end
             -- Forward command results back to web server
             local resultType = message.type
             if resultType == "order_result" or resultType == "craft_result"
@@ -395,6 +366,30 @@ local function wsConnector()
     })
 end
 
+-- Task 6: Retry unacknowledged modem commands
+-- The manager deduplicates by commandId, so retransmits are safe.
+local function modemRetry()
+    while running do
+        local now = os.clock()
+        for cmdId, entry in pairs(pendingModem) do
+            if now - entry.sent >= MODEM_RETRY_DELAY then
+                if entry.retries >= MODEM_RETRY_MAX then
+                    print(string.format("[RETRY] Giving up on %s after %d retries",
+                        tostring(cmdId), entry.retries))
+                    pendingModem[cmdId] = nil
+                else
+                    entry.retries = entry.retries + 1
+                    entry.sent = now
+                    print(string.format("[RETRY] Re-transmit %s (attempt %d/%d)",
+                        tostring(cmdId), entry.retries, MODEM_RETRY_MAX))
+                    pcall(modem.transmit, ORDER_CHANNEL, BRIDGE_REPLY_CHANNEL, entry.payload)
+                end
+            end
+        end
+        sleep(MODEM_RETRY_INTERVAL)
+    end
+end
+
 -------------------------------------------------
 -- Main
 -------------------------------------------------
@@ -437,7 +432,8 @@ local function main()
         stateForwarder,
         commandPoller,
         heartbeat,
-        wsConnector
+        wsConnector,
+        modemRetry
     )
 end