feat(*): inkless app for the mxw01 thermal printer

InklessTests/ImagingTests.swift

@@ -0,0 +1,44 @@
+import Foundation
+@testable import Inkless
+import Testing
+
+struct ImagingTests {
+    @Test func packsLeftmostDotIntoLowestBit() {
+        var dots = [UInt8](repeating: 0, count: 16)
+        dots[0] = 1
+        dots[9] = 1
+        let bitmap = DotBitmap(width: 16, height: 1, dots: dots)
+        #expect([UInt8](bitmap.packedRows()) == [0b0000_0001, 0b0000_0010])
+    }
+
+    @Test func packsGrayAsInvertedNibblesHighFirst() {
+        let bitmap = GrayBitmap(width: 4, height: 1, luma: [255, 0, 128, 16])
+        #expect([UInt8](bitmap.packedNibbles()) == [0x0F, 0x7E])
+    }
+
+    @Test func padsShortJobsWithPaper() {
+        let raster = PrintRaster.dots(.blank(rows: 10)).padded(toMinimumHeight: 90)
+        #expect(raster.height == 90)
+        #expect(raster.blackRatio == 0)
+    }
+
+    @Test(arguments: DitherAlgorithm.allCases)
+    func ditherKeepsExtremesAndAverageTone(algorithm: DitherAlgorithm) {
+        let side = 64
+        let white = algorithm.apply(to: .init(repeating: 1, count: side * side), width: side, height: side)
+        let black = algorithm.apply(to: .init(repeating: 0, count: side * side), width: side, height: side)
+        #expect(white.allSatisfy { $0 == 0 })
+        #expect(black.allSatisfy { $0 == 1 })
+
+        guard algorithm != .threshold else { return }
+        let grey = algorithm.apply(to: .init(repeating: 0.5, count: side * side), width: side, height: side)
+        let ratio = Double(grey.reduce(0) { $0 + Int($1) }) / Double(grey.count)
+        #expect(abs(ratio - 0.5) < 0.15)
+    }
+
+    @Test func textRendersToHeadWidth() throws {
+        let raster = try #require(TextRenderer.render("Milk\nBread", style: TextStyle()))
+        #expect(raster.width == PrintHead.dots)
+        #expect(raster.blackRatio > 0)
+    }
+}

InklessTests/ProtocolTests.swift

@@ -0,0 +1,59 @@
+import Foundation
+@testable import Inkless
+import Testing
+
+struct ProtocolTests {
+    @Test func crcMatchesVendorFrames() {
+        #expect(MXW.crc8([0x5D]) == 0x94)
+        #expect(MXW.crc8([0x00]) == 0x00)
+    }
+
+    @Test func framesMatchVendorBytes() {
+        #expect(MXW.density(93).hexString == "2221A20001005D94FF")
+        #expect(MXW.startPrint(rows: 384, mode: .dots).hexString == "2221A9000400800130000000")
+        #expect(MXW.startPrint(rows: 384, mode: .gray).hexString == "2221A9000400800130020000")
+        #expect(MXW.flush().hexString == "2221AD000100000000")
+        #expect(MXW.cancel().hexString == "2221AC0001000000FF")
+        #expect(MXW.versionRequest().hexString == "2221B10001000000FF")
+    }
+
+    @Test func challengeReplyMatchesReferenceEncoder() throws {
+        let challenge: [UInt8] = [0x00, 0x11, 0x22, 0x33, 0x44, 0x55, 0x66, 0x77, 0x88, 0x99]
+        let reply = try #require(MXW.challengeResponse(to: challenge, now: Date(timeIntervalSince1970: 1_234_567_895.678)))
+        #expect(reply.hexString == "2221B3002200834EF9578D0451A26B80DAD95BAEDFC6352026B9F2D7C0D3CB1702488E5738E4868D00FF")
+    }
+
+    @Test func parsesStatus() throws {
+        let data = try #require(Data(hexString: "2221A1010900" + "01" + "0000" + "57" + "1F" + "00" + "01" + "04" + "00" + "00FF"))
+        let expected = MXW.Status(activity: .printing, battery: 87, temperature: 31, fault: .overheated)
+        #expect(MXW.parse(data) == .status(expected))
+    }
+
+    @Test func parsesBothFlowControlForms() throws {
+        #expect(try MXW.parse(#require(Data(hexString: "2221AE0101001070FF"))) == .flowPause)
+        #expect(try MXW.parse(#require(Data(hexString: "2221AE0101000000FF"))) == .flowResume)
+        #expect(try MXW.parse(#require(Data(hexString: "2221AE0001000000"))) == .flowPause)
+        #expect(try MXW.parse(#require(Data(hexString: "2221AE0001001000"))) == .flowResume)
+    }
+
+    @Test func parsesFirmwareAndHeadType() throws {
+        let text = "MXW 2.1 2"
+        let payload = text.utf8.map { String(format: "%02X", $0) }.joined()
+        let data = try #require(Data(hexString: "2221B1010900" + payload + "00FF"))
+        #expect(MXW.parse(data) == .version(text, .highVoltage))
+    }
+
+    @Test func grayDepthFollowsFirmware() {
+        #expect(MXW.usesFourBitGray(firmware: nil))
+        #expect(MXW.usesFourBitGray(firmware: "MXW 2.1 2"))
+        #expect(!MXW.usesFourBitGray(firmware: "MXW 1.9 1"))
+        #expect(!MXW.usesFourBitGray(firmware: "MXW 2.0 1"))
+    }
+
+    @Test func densityDropsOnlyWhenHot() {
+        let cool = MXW.compensatedDensity(requested: 93, temperature: 40, blackRatio: 0.8, head: .highVoltage, mode: .dots)
+        let hot = MXW.compensatedDensity(requested: 93, temperature: 66, blackRatio: 0.8, head: .highVoltage, mode: .dots)
+        #expect(cool == 93)
+        #expect(hot == 5)
+    }
+}