name: Build pinned NoMount metamodule
description: Package a flashable NoMount metamodule from the exact kernel integration SHA
inputs:
  commit:
    description: 'Full immutable NoMount commit SHA'
    required: true
outputs:
  module_path:
    description: 'Path to the flashable metamodule ZIP'
    value: ${{ steps.package.outputs.module_path }}
  module_dir:
    description: 'Path to the extracted metamodule directory (module.prop, bin/, ...)'
    value: ${{ steps.package.outputs.module_dir }}
  commit:
    description: 'Verified NoMount source SHA'
    value: ${{ steps.package.outputs.commit }}

runs:
  using: composite
  steps:
    - name: Set up Zig
      uses: jetsung/setup-zig@v0.0.4
      with:
        version: master

    - name: Build and package matching metamodule
      id: package
      shell: bash
      run: |
        set -euo pipefail

        expected_commit="${{ inputs.commit }}"
        if ! [[ "$expected_commit" =~ ^[0-9a-f]{40}$ ]]; then
          echo "NoMount commit must be a full 40-character SHA." >&2
          exit 2
        fi

        source_dir="${RUNNER_TEMP}/nomount-module-source"
        module_dir="${RUNNER_TEMP}/nomount-metamodule"
        module_zip="${RUNNER_TEMP}/NoMount-${expected_commit}.zip"
        git clone --no-checkout https://github.com/maxsteeel/nomount.git "$source_dir"
        git -C "$source_dir" fetch --depth=1 origin "$expected_commit"
        git -C "$source_dir" checkout --detach "$expected_commit"
        actual_commit="$(git -C "$source_dir" rev-parse HEAD)"
        if [ "$actual_commit" != "$expected_commit" ]; then
          echo "NoMount module source mismatch: expected $expected_commit, got $actual_commit." >&2
          exit 1
        fi

        mkdir -p "$source_dir/bin"
        (
          cd "$source_dir/userspace/src"
          zig cc -target aarch64-linux -Oz -mcmodel=tiny -static -nostdlib \
            -ffreestanding -fno-unwind-tables -fno-ident -Wno-invalid-noreturn \
            -Wl,--entry=_start nm.c -o ../../bin/nm-arm64
          zig cc -target arm-linux -Oz -static -nostdlib -ffreestanding \
            -fno-unwind-tables -fno-ident -Wno-invalid-noreturn \
            -ffunction-sections -fdata-sections -Wl,--gc-sections \
            -Wl,--entry=_start nm.c -o ../../bin/nm-arm
        )

        cp -a "$source_dir/module" "$module_dir"
        mkdir -p "$module_dir/bin"
        install -m 0755 "$source_dir/bin/nm-arm64" "$module_dir/bin/nm-arm64"
        install -m 0755 "$source_dir/bin/nm-arm" "$module_dir/bin/nm-arm"
        sed -i "s/^versionCode=.*/versionCode=1/" "$module_dir/module.prop"
        printf '%s\n' "$actual_commit" > "$module_dir/NOMOUNT_SOURCE_COMMIT"
        (
          cd "$module_dir"
          zip -qr "$module_zip" .
        )
        sha256sum "$module_zip" > "${module_zip}.sha256"
        echo "module_path=$module_zip" >> "$GITHUB_OUTPUT"
        echo "module_dir=$module_dir" >> "$GITHUB_OUTPUT"
        echo "commit=$actual_commit" >> "$GITHUB_OUTPUT"