Support kicad-footprint-library for the tsci export command

cli/build/generate-kicad-footprint-library.ts

@@ -145,3 +145,39 @@ export const generateKicadFootprintLibrary = async ({
     fs.writeFileSync(path.join(libraryRoot, "fp-lib-table"), libTableContent)
   }
 }
+
+export type FootprintEntry = {
+  libraryName: string
+  footprintName: string
+  content: string
+}
+
+export const extractFootprintsFromPcb = (
+  pcbContent: string,
+): FootprintEntry[] => {
+  const uniqueFootprints = new Map<string, FootprintEntry>()
+
+  try {
+    const parsed = parseKicadSexpr(pcbContent)
+    const pcb = parsed.find(
+      (node): node is KicadPcb => node instanceof KicadPcb,
+    )
+    if (!pcb) return []
+
+    const footprints = pcb.footprints ?? []
+    for (const footprint of footprints) {
+      const sanitized = sanitizeFootprint(footprint)
+      const key = `${sanitized.libraryName}::${sanitized.footprintName}`
+      if (!uniqueFootprints.has(key)) {
+        uniqueFootprints.set(key, sanitized)
+      }
+    }
+  } catch (error) {
+    console.warn(
+      "Failed to parse KiCad PCB content for footprint extraction:",
+      error,
+    )
+  }
+
+  return Array.from(uniqueFootprints.values())
+}

lib/shared/export-snippet.ts

@@ -15,6 +15,7 @@ import {
 import JSZip from "jszip"
 import { generateCircuitJson } from "lib/shared/generate-circuit-json"
 import type { PlatformConfig } from "@tscircuit/props"
+import { extractFootprintsFromPcb } from "cli/build/generate-kicad-footprint-library"
 
 const writeFileAsync = promisify(fs.writeFile)
 
@@ -31,6 +32,7 @@ export const ALLOWED_EXPORT_FORMATS = [
   "kicad_sch",
   "kicad_pcb",
   "kicad_zip",
+  "kicad-footprint-library",
 ] as const
 
 export type ExportFormat = (typeof ALLOWED_EXPORT_FORMATS)[number]
@@ -48,6 +50,7 @@ const OUTPUT_EXTENSIONS: Record<ExportFormat, string> = {
   kicad_sch: ".kicad_sch",
   kicad_pcb: ".kicad_pcb",
   kicad_zip: "-kicad.zip",
+  "kicad-footprint-library": "-footprints.zip",
 }
 
 type ExportOptions = {
@@ -160,6 +163,43 @@ export const exportSnippet = async ({
       outputContent = await zip.generateAsync({ type: "nodebuffer" })
       break
     }
+    case "kicad-footprint-library": {
+      const pcbConverter = new CircuitJsonToKicadPcbConverter(
+        circuitData.circuitJson,
+      )
+      pcbConverter.runUntilFinished()
+      const pcbContent = pcbConverter.getOutputString()
+
+      const footprintEntries = extractFootprintsFromPcb(pcbContent)
+
+      const zip = new JSZip()
+      const libraryNames = new Set<string>()
+
+      for (const entry of footprintEntries) {
+        libraryNames.add(entry.libraryName)
+        const libraryFolder = zip.folder(`${entry.libraryName}.pretty`)
+        if (libraryFolder) {
+          libraryFolder.file(
+            `${entry.footprintName}.kicad_mod`,
+            `${entry.content}\n`,
+          )
+        }
+      }
+
+      if (libraryNames.size > 0) {
+        const libTableEntries = Array.from(libraryNames)
+          .sort()
+          .map(
+            (name) =>
+              `  (lib (name ${name}) (type KiCad) (uri \${KIPRJMOD}/${name}.pretty) (options "") (descr "Generated by tsci export"))`,
+          )
+        const libTableContent = `(fp_lib_table\n${libTableEntries.join("\n")}\n)\n`
+        zip.file("fp-lib-table", libTableContent)
+      }
+
+      outputContent = await zip.generateAsync({ type: "nodebuffer" })
+      break
+    }
     default:
       outputContent = JSON.stringify(circuitData.circuitJson, null, 2)
   }

tests/cli/export/export-kicad-footprint-library.test.ts

@@ -0,0 +1,68 @@
+import { getCliTestFixture } from "../../fixtures/get-cli-test-fixture"
+import { test, expect } from "bun:test"
+import { writeFile, readFile } from "node:fs/promises"
+import path from "node:path"
+import JSZip from "jszip"
+
+const circuitCode = `
+export default () => (
+  <board width="10mm" height="10mm">
+    <resistor
+      resistance="1k"
+      footprint="0402"
+      name="R1"
+      schX={3}
+      pcbX={3}
+    />
+    <capacitor
+      capacitance="1000pF"
+      footprint="0402"
+      name="C1"
+      schX={-3}
+      pcbX={-3}
+    />
+    <trace from=".R1 > .pin1" to=".C1 > .pin1" />
+  </board>
+)`
+
+test("export kicad footprint library", async () => {
+  const { tmpDir, runCommand } = await getCliTestFixture()
+  const circuitPath = path.join(tmpDir, "test-circuit.tsx")
+
+  await writeFile(circuitPath, circuitCode)
+
+  const { stderr } = await runCommand(
+    `tsci export ${circuitPath} -f kicad-footprint-library`,
+  )
+
+  expect(stderr).toBe("")
+
+  const zipBuffer = await readFile(
+    path.join(tmpDir, "test-circuit-footprints.zip"),
+  )
+
+  const zip = await JSZip.loadAsync(zipBuffer)
+
+  // Check that fp-lib-table exists
+  const libTable = zip.file("fp-lib-table")
+  expect(libTable).not.toBeNull()
+
+  const libTableContent = await libTable!.async("string")
+  expect(libTableContent).toContain("fp_lib_table")
+  expect(libTableContent).toContain("KiCad")
+
+  // Check that at least one .pretty folder with .kicad_mod file exists
+  const files = Object.keys(zip.files)
+  const prettyFolders = files.filter((f) => f.includes(".pretty/"))
+  expect(prettyFolders.length).toBeGreaterThan(0)
+
+  const kicadModFiles = files.filter((f) => f.endsWith(".kicad_mod"))
+  expect(kicadModFiles.length).toBeGreaterThan(0)
+
+  // Check content of a footprint file
+  const firstFootprint = zip.file(kicadModFiles[0])
+  expect(firstFootprint).not.toBeNull()
+
+  const footprintContent = await firstFootprint!.async("string")
+  expect(footprintContent).toContain("footprint")
+}, 60_000)