name: 'Apply Device-Specific Patches'
description: 'Apply WiFi/Bluetooth fixes for Samsung and Xiaomi 6.6 GKI devices'

inputs:
  version:
    description: 'Kernel config version (e.g., android15-6.6)'
    required: true
  kernel_version:
    description: 'Kernel version (e.g., 6.6)'
    required: true

runs:
  using: "composite"
  steps:
    - name: Fix WiFi and Bluetooth on Samsung 6.6 GKI Devices
      if: inputs.version == 'android15-6.6'
      shell: bash
      working-directory: ${{ github.workspace }}/kernel/common
      run: |
        set -euo pipefail

        PATCH="${{ github.workspace }}/kernel_patches/samsung/min_kdp/add-min_kdp-symbols.patch"
        MIN_KDP="${{ github.workspace }}/kernel_patches/samsung/min_kdp/min_kdp.c"
        test -f "$PATCH" || { echo "Missing Samsung min_kdp patch: $PATCH" >&2; exit 1; }
        test -f "$MIN_KDP" || { echo "Missing Samsung min_kdp source: $MIN_KDP" >&2; exit 1; }

        SYMBOL_LIST=android/abi_gki_aarch64_galaxy
        TRANSACTION_DIR="$(mktemp -d)"
        BACKUP_DIR="$TRANSACTION_DIR/original"
        STAGE_DIR="$TRANSACTION_DIR/stage"
        TRANSACTION_COMMITTED=false
        declare -a TRANSACTION_PATHS
        TRANSACTION_PATH_COUNT=0

        add_transaction_path() {
          local path="$1"
          case "$path" in
            /dev/null|..|../*|*/../*|/*)
              echo "Unsafe Samsung patch path: $path" >&2
              exit 1
              ;;
          esac
          local index existing
          for ((index = 0; index < TRANSACTION_PATH_COUNT; index++)); do
            existing="${TRANSACTION_PATHS[index]}"
            [ "$existing" = "$path" ] && return
          done
          TRANSACTION_PATHS[TRANSACTION_PATH_COUNT]="$path"
          TRANSACTION_PATH_COUNT=$((TRANSACTION_PATH_COUNT + 1))
        }

        restore_transaction() {
          set +e
          set +u
          if [ "$TRANSACTION_COMMITTED" = true ]; then
            rm -rf "$TRANSACTION_DIR"
            return
          fi
          local index path
          for ((index = 0; index < TRANSACTION_PATH_COUNT; index++)); do
            path="${TRANSACTION_PATHS[index]}"
            if [[ -e "$BACKUP_DIR/$path" || -L "$BACKUP_DIR/$path" ]]; then
              rm -rf "$path"
              mkdir -p "$(dirname "$path")"
              cp -a "$BACKUP_DIR/$path" "$path"
            else
              rm -rf "$path"
            fi
          done
          rm -rf "$TRANSACTION_DIR"
        }
        trap restore_transaction EXIT

        PATCH_PATHS=()
        while IFS= read -r path; do
          [ -n "$path" ] && PATCH_PATHS+=("$path")
        done < <(awk '/^(---|\+\+\+) / { path=$2; sub(/^[ab]\//, "", path); print path }' "$PATCH" | sort -u)
        for path in "${PATCH_PATHS[@]}"; do
          add_transaction_path "$path"
        done
        add_transaction_path "$SYMBOL_LIST"
        add_transaction_path drivers/min_kdp.c
        add_transaction_path drivers/Makefile

        for path in "${TRANSACTION_PATHS[@]}"; do
          if [[ -e "$path" || -L "$path" ]]; then
            mkdir -p "$BACKUP_DIR/$(dirname "$path")" "$STAGE_DIR/$(dirname "$path")"
            cp -a "$path" "$BACKUP_DIR/$path"
            cp -a "$path" "$STAGE_DIR/$path"
          else
            mkdir -p "$STAGE_DIR/$(dirname "$path")"
          fi
        done

        (
          cd "$STAGE_DIR"
          patch -p1 --dry-run < "$PATCH"
          patch -p1 --no-backup-if-mismatch < "$PATCH"
          printf '%s\n' \
            'kdp_set_cred_non_rcu' \
            'kdp_usecount_dec_and_test' \
            'kdp_usecount_inc' >> "$SYMBOL_LIST"
          cp "$MIN_KDP" drivers/min_kdp.c
          if ! grep -Fqx 'obj-y += min_kdp.o' drivers/Makefile; then
            printf '%s\n' 'obj-y += min_kdp.o' >> drivers/Makefile
          fi
        )

        for path in "${TRANSACTION_PATHS[@]}"; do
          if [[ -e "$STAGE_DIR/$path" || -L "$STAGE_DIR/$path" ]]; then
            mkdir -p "$(dirname "$path")"
            rm -rf "$path"
            cp -a "$STAGE_DIR/$path" "$path"
          else
            rm -rf "$path"
          fi
        done
        TRANSACTION_COMMITTED=true

    - name: Fix WiFi and Bluetooth on Xiaomi 6.6 GKI Devices
      if: inputs.version == 'android15-6.6'
      shell: bash
      working-directory: ${{ github.workspace }}/kernel/common
      run: |
        SYMBOL_LIST=android/abi_gki_aarch64_xiaomi
        echo "device_find_any_child" >> $SYMBOL_LIST