pr-checks.yml

name: PR Checks

on:
  pull_request:
    branches: [main]

# Only run one check per PR to save resources
concurrency:
  group: pr-checks-${{ github.ref }}
  cancel-in-progress: true

jobs:
  # ============================================
  # Detect which files changed to skip unnecessary jobs
  # ============================================
  changes:
    name: Detect Changes
    runs-on: ubuntu-latest
    permissions:
      pull-requests: read
    outputs:
      haskell: ${{ steps.filter.outputs.haskell }}
      typescript: ${{ steps.filter.outputs.typescript }}
      docs: ${{ steps.filter.outputs.docs }}
    steps:
      - uses: dorny/paths-filter@v3
        id: filter
        with:
          filters: |
            haskell:
              - '**/*.hs'
              - '**/*.cabal'
              - 'cabal.project'
              - 'cabal.project.local'
              - 'jl4-core/libraries/**'
            typescript:
              - '**/*.ts'
              - '**/*.tsx'
              - '**/*.js'
              - '**/*.svelte'
              - 'package.json'
              - 'package-lock.json'
              - 'ts-apps/**'
              - 'ts-shared/**'
            docs:
              - 'doc/**'

  # ============================================
  # TypeScript: Lint, Format, Build & Test (combined)
  # ============================================
  typescript:
    name: TypeScript Checks
    needs: changes
    if: needs.changes.outputs.typescript == 'true'
    runs-on: ubuntu-latest
    container:
      image: ubuntu:24.04
    steps:
      - name: Update repositories
        run: apt update
      - name: Install deps
        run: apt install -y git sudo software-properties-common curl xvfb
      - name: Update git config
        run: git config --global --add safe.directory $GITHUB_WORKSPACE
      - uses: actions/checkout@v4

      - name: Use Node.js
        uses: actions/setup-node@v4
        with:
          cache-dependency-path: package-lock.json
          node-version: "20.x"
          cache: npm

      - run: npm ci
      - run: npm run build
      - run: npm run lint
      - run: npm run format:check
      - run: npm run check
      - run: xvfb-run -a npm run test

  # ============================================
  # Haskell: Build & Tests
  # ============================================
  haskell:
    name: Haskell Build & Test
    needs: changes
    if: needs.changes.outputs.haskell == 'true' || needs.changes.outputs.docs == 'true'
    runs-on: ubuntu-latest
    container:
      image: ubuntu:24.04
    env:
      LC_ALL: C.UTF-8
      LANG: C.UTF-8

    steps:
      - name: Update repositories
        run: apt update
      - name: Install deps
        run: >
          apt install -y
          git
          sudo
          software-properties-common
          build-essential
          curl
          libffi-dev
          libffi8
          libgmp-dev
          libgmp10
          libncurses-dev
          pkg-config
          zlib1g-dev
          liblzma-dev
          xz-utils
      - name: Update git config
        run: git config --global --add safe.directory $GITHUB_WORKSPACE
      - uses: actions/checkout@v4

      - name: Update git submodules
        run: git submodule update --init

      - name: Set up GHC
        uses: haskell-actions/setup@v2
        id: setup
        with:
          ghc-version: "9.10.2"
          cabal-version: "latest"
          cabal-update: true

      # Restore caches BEFORE configure so cabal can plan incrementally
      # on top of existing build state rather than starting fresh.
      - name: Restore cached build artifacts
        uses: actions/cache/restore@v4
        id: build-cache
        with:
          path: dist-newstyle
          key: ${{ runner.os }}-ghc-${{ steps.setup.outputs.ghc-version }}-dist-${{ hashFiles('**/*.hs', '**/*.cabal') }}
          restore-keys: |
            ${{ runner.os }}-ghc-${{ steps.setup.outputs.ghc-version }}-dist-

      - name: Restore cached dependencies
        uses: actions/cache/restore@v4
        id: deps-cache
        env:
          key: ${{ runner.os }}-ghc-${{ steps.setup.outputs.ghc-version }}-cabal-${{ steps.setup.outputs.cabal-version }}
        with:
          path: ${{ steps.setup.outputs.cabal-store }}
          key: ${{ env.key }}-plan-${{ hashFiles('**/*.cabal', 'cabal.project') }}
          restore-keys: ${{ env.key }}-

      - name: Configure the build
        run: |
          cabal update
          cabal configure --enable-tests --enable-benchmarks --disable-documentation
          cabal build all --dry-run

      - name: Install dependencies
        if: steps.deps-cache.outputs.cache-hit != 'true'
        run: cabal build all --only-dependencies

      - name: Save cached dependencies
        uses: actions/cache/save@v4
        if: steps.deps-cache.outputs.cache-hit != 'true'
        with:
          path: ${{ steps.setup.outputs.cabal-store }}
          key: ${{ steps.deps-cache.outputs.cache-primary-key }}

      - name: Build
        run: cabal build all

      - name: Save cached build artifacts
        uses: actions/cache/save@v4
        if: success()
        with:
          path: dist-newstyle
          key: ${{ runner.os }}-ghc-${{ steps.setup.outputs.ghc-version }}-dist-${{ hashFiles('**/*.hs', '**/*.cabal') }}

      - name: Run tests
        run: cabal test all
        env:
          JL4_LIBRARY_PATH: ${{ github.workspace }}/jl4-core/libraries

      - name: Run documentation tests
        run: ./doc/test-docs.sh

  # ============================================
  # WASM Build & Test (only when Haskell changes)
  # ============================================
  wasm-build:
    name: WASM Build & Test
    needs: changes
    if: needs.changes.outputs.haskell == 'true'
    runs-on: ubuntu-latest
    env:
      GHC_WASM_VERSION: "9.10"

    steps:
      - name: Checkout code
        uses: actions/checkout@v4
        with:
          submodules: true

      - name: Install system dependencies
        run: |
          sudo apt-get update
          sudo apt-get install -y curl xz-utils binaryen

      - name: Cache GHC WASM toolchain
        id: cache-ghc-wasm
        uses: actions/cache@v4
        with:
          path: ~/.ghc-wasm
          key: ghc-wasm-${{ env.GHC_WASM_VERSION }}-${{ runner.os }}

      - name: Install GHC WASM toolchain
        if: steps.cache-ghc-wasm.outputs.cache-hit != 'true'
        run: |
          curl -L https://gitlab.haskell.org/haskell-wasm/ghc-wasm-meta/-/raw/master/bootstrap.sh | FLAVOUR=${{ env.GHC_WASM_VERSION }} bash
        shell: bash

      - name: Verify GHC WASM installation
        run: |
          source ~/.ghc-wasm/env
          wasm32-wasi-ghc --version
          wasm32-wasi-cabal --version

      - name: Cache WASM dependencies
        uses: actions/cache@v4
        with:
          path: |
            ~/.ghc-wasm/.cabal/store
            dist-newstyle
          key: wasm-deps-${{ env.GHC_WASM_VERSION }}-${{ hashFiles('cabal-wasm.project', 'jl4-core/jl4-core.cabal', 'jl4-wasm/jl4-wasm.cabal') }}
          restore-keys: |
            wasm-deps-${{ env.GHC_WASM_VERSION }}-

      - name: Build WASM binary
        run: |
          source ~/.ghc-wasm/env
          wasm32-wasi-cabal update
          wasm32-wasi-cabal build jl4-wasm --project-file=cabal-wasm.project

      - name: Generate JS FFI glue code
        run: |
          source ~/.ghc-wasm/env
          WASM_PATH=$(find dist-newstyle -name 'jl4-wasm.wasm' -path '*/opt/build/*' | head -1)
          echo "Found WASM at: $WASM_PATH"
          $(wasm32-wasi-ghc --print-libdir)/post-link.mjs -i "$WASM_PATH" -o dist-newstyle/jl4-wasm.mjs

      - name: Optimize WASM binary
        run: |
          WASM_PATH=$(find dist-newstyle -name 'jl4-wasm.wasm' -path '*/opt/build/*' | head -1)
          echo "Running wasm-opt with -Oz..."
          wasm-opt -Oz "$WASM_PATH" -o "$WASM_PATH.opt"
          mv "$WASM_PATH.opt" "$WASM_PATH"
          echo "WASM binary size (after wasm-opt):"
          ls -lh "$WASM_PATH"

      - name: Test WASM binary loads
        run: |
          source ~/.ghc-wasm/env
          WASM_PATH=$(find dist-newstyle -name 'jl4-wasm.wasm' -path '*/opt/build/*' | head -1)

          ~/.ghc-wasm/nodejs/bin/node -e "
            const fs = require('fs');
            
            async function test() {
              console.log('Loading WASM module...');
              const wasmBuffer = fs.readFileSync('$WASM_PATH');
              const module = await WebAssembly.compile(wasmBuffer);
              
              console.log('Module compiled successfully');
              console.log('Exports:', WebAssembly.Module.exports(module).map(e => e.name).slice(0, 10), '...');
              
              // Check for our expected exports
              const exports = WebAssembly.Module.exports(module).map(e => e.name);
              const required = ['l4_check', 'l4_hover', 'l4_completions', 'l4_semantic_tokens', 'l4_eval'];
              const missing = required.filter(r => !exports.includes(r));
              
              if (missing.length > 0) {
                console.error('Missing exports:', missing);
                process.exit(1);
              }
              
              console.log('All required exports present!');
            }
            
            test().catch(e => { console.error(e); process.exit(1); });
          "

      - name: Build summary
        run: |
          WASM_PATH=$(find dist-newstyle -name 'jl4-wasm.wasm' -path '*/opt/build/*' | head -1)
          WASM_SIZE=$(stat --format=%s "$WASM_PATH")
          WASM_SIZE_MB=$(echo "scale=2; $WASM_SIZE / 1048576" | bc)

          echo "## WASM Build Summary" >> $GITHUB_STEP_SUMMARY
          echo "" >> $GITHUB_STEP_SUMMARY
          echo "- **GHC WASM:** ${{ env.GHC_WASM_VERSION }}" >> $GITHUB_STEP_SUMMARY
          echo "- **Binary Size:** ${WASM_SIZE_MB} MB" >> $GITHUB_STEP_SUMMARY
          echo "- **Status:** All tests passed" >> $GITHUB_STEP_SUMMARY

  # ============================================
  # Nix Flake Check
  # ============================================
  nix-check:
    name: Nix Flake Check
    runs-on: ubuntu-latest
    permissions:
      id-token: "write"
      contents: "read"
    steps:
      - uses: actions/checkout@v4
      - uses: cachix/install-nix-action@v31
      - run: nix flake check
      - run: nix -Lv build .#jl4-web