name: "Maintenance: Rewrite patches"

on:
  workflow_dispatch:
    inputs:
      board:
        description: "Board name (e.g. bananapim5, khadas-vim3)"
        required: true
        type: string
      branch:
        description: "Branch to use"
        required: true
        type: choice
        options:
          - legacy
          - vendor
          - current
          - edge
      whattodo:
        description: "rewrite uboot or kernel patches"
        required: true
        type: choice
        options:
          - rewrite-kernel-patches
          - rewrite-uboot-patches

permissions:
  contents: write
  pull-requests: write

jobs:
  rewrite-patches:
    name: "Rewrite ${{ inputs.board }} (${{ inputs.branch }})"
    runs-on: rewrite
    timeout-minutes: 60
    steps:
      - name: Update existing repository
        env:
          REF_NAME: ${{ github.ref_name }}
          REPO: ${{ github.repository }}
        run: |
          # Clone or update the repository
          if [ -d .git ]; then
            # Repo exists: update it
            git fetch origin "$REF_NAME"
            git checkout "$REF_NAME"
            git reset --hard "origin/$REF_NAME"
            git clean -fd
          else
            # No repo: clone it
            git clone --depth 1 --filter=blob:none -b "$REF_NAME" "https://github.com/${REPO}" .
            git checkout "$REF_NAME"
          fi

      - name: "Run ${{ inputs.whattodo }}"
        env:
          BOARD: ${{ inputs.board }}
          BRANCH: ${{ inputs.branch }}
          WHATTODO: ${{ inputs.whattodo }}
        run: |
          ./compile.sh "BOARD=$BOARD" "BRANCH=$BRANCH" "$WHATTODO" KERNEL_GIT=shallow

      - name: Check for changes
        env:
          WHATTODO: ${{ inputs.whattodo }}
        id: check_changes
        run: |
          set -euo pipefail
          if git diff --quiet; then
            echo "has_changes=false" >> "$GITHUB_OUTPUT"
            echo "::notice::No changes detected after ${WHATTODO}"
          else
            echo "has_changes=true" >> "$GITHUB_OUTPUT"
            echo "::notice::Changes detected after ${WHATTODO} - PR will be created"
          fi

      - name: Build PR body
        env:
          WHATTODO: ${{ inputs.whattodo }}
        id: build_pr_body
        if: steps.check_changes.outputs.has_changes == 'true'
        run: |
          set -euo pipefail

          # Per-file stats
          tmp_stats=$(mktemp)
          tmp_body=$(mktemp)
          git diff --numstat > "$tmp_stats" || true

          total_add=0; total_del=0; files=0
          {
            echo "| File | + | - | Δ |"
            echo "|---|---:|---:|---:|"
            while IFS=$'\t' read -r add del path; do
              [[ -z "${path:-}" ]] && continue
              [[ "$add" =~ ^[0-9]+$ ]] || add=0
              [[ "$del" =~ ^[0-9]+$ ]] || del=0
              delta=$(( add - del ))
              total_add=$(( total_add + add ))
              total_del=$(( total_del + del ))
              files=$(( files + 1 ))
              path_esc="${path//|/\\|}"
              printf "| %s | %d | %d | %d |\n" "$path_esc" "$add" "$del" "$delta"
            done < "$tmp_stats"
            echo
            printf "**Files:** %d  •  **Lines:** +%d / -%d  (Δ %d)\n" "$files" "$total_add" "$total_del" "$(( total_add - total_del ))"
          } > "$tmp_body"

          echo "pr_body_path=$tmp_body" >> "$GITHUB_OUTPUT"

      - name: Open / Update PR
        id: create_pr
        if: steps.check_changes.outputs.has_changes == 'true'
        uses: peter-evans/create-pull-request@v8
        with:
          token: ${{ secrets.GITHUB_TOKEN }}
          branch: rewrite-patches/${{ inputs.board }}-${{ inputs.branch }}
          delete-branch: true
          base: main
          title: "`[${{ inputs.branch }}]` `${{ inputs.whattodo }}` for `${{ inputs.board }}`"
          commit-message: "[${{ inputs.branch }}] ${{ inputs.whattodo }} for ${{ inputs.board }}"
          body-path: ${{ steps.build_pr_body.outputs.pr_body_path }}
          labels: |
            Needs review

      - name: Cleanup temp files
        if: steps.build_pr_body.outputs.pr_body_path != ''
        run: |
          rm -f "${{ steps.build_pr_body.outputs.pr_body_path }}" || true

      - name: Reset working directory for next run
        if: always()
        run: |
          git reset --hard HEAD
          git clean -fd