name: "Discover and Detect Skins"
description: "Find all skins and detect which ones changed since last tag or based on inputs"

inputs:
  force_rebuild:
    description: "Force rebuild all skins"
    required: false
    default: "false"
  target_skins:
    description: "JSON array of skins to rebuild (e.g., '[\"skin1\", \"skin2\"]')"
    required: false
    default: ""

outputs:
  changed_skins_file:
    description: "Path to file containing changed skins"
    value: ${{ steps.detect.outputs.changed_skins_file }}
  all_skins:
    description: "All discovered skins (JSON array)"
    value: ${{ steps.discover_all.outputs.all_skins }}

runs:
  using: "composite"
  steps:
    - name: Checkout caller repository
      uses: actions/checkout@v4
      with:
        repository: ${{ github.repository }}
        ref: ${{ github.ref }}
        fetch-depth: 0
        path: .

    - name: Fetch tags manually
      shell: bash
      run: |
        git fetch origin --tags --force --prune
        git tag -l

    - name: Discover all skins
      id: discover_all
      shell: bash
      run: |
        all_skins_file="/tmp/all_skins_shared.json"
        find "$SKINS_DIR" -mindepth 1 -maxdepth 1 -type d -print0 \
          | while IFS= read -r -d '' dir; do basename "$dir"; done \
          | jq -R . | jq -cs . > "$all_skins_file"
        json=$(cat "$all_skins_file")
        {
          echo "all_skins<<EOF"
          echo "$json"
          echo "EOF"
        } >> "$GITHUB_OUTPUT"
        echo "all_skins_file=$all_skins_file" >> "$GITHUB_OUTPUT"

    - name: Detect Changed Skin Directories
      id: detect
      shell: bash
      run: |
        set -e

        all_skins_file="/tmp/all_skins_shared.json"
        temp_all_skins="/tmp/all_skins_raw_$RANDOM.txt"
        jq -r '.[]' "$all_skins_file" > "$temp_all_skins"
        mapfile -t all_skins < "$temp_all_skins"
        rm -f "$temp_all_skins"

        force_rebuild='${{ inputs.force_rebuild }}'
        target_skins='${{ inputs.target_skins }}'
        skins=()
        deleted_skins=()

        if [[ "$force_rebuild" == "true" ]]; then
          skins=("${all_skins[@]}")

        elif [[ -n "$target_skins" && "$target_skins" != "" ]]; then
          temp_target_file="/tmp/target_skins_$RANDOM.json"
          printf '%s' "$target_skins" > "$temp_target_file"
          mapfile -t skins < <(jq -r '.[]' "$temp_target_file")
          rm -f "$temp_target_file"

        else
          latest_tag=$(git tag --sort=-version:refname | head -n 1)

          if [[ -n "$latest_tag" ]]; then
            mapfile -t skins < <(
              git diff --name-only -z --diff-filter=AM "$latest_tag" HEAD \
                | while IFS= read -r -d '' file; do
                    [[ $file == Skins/* ]] && echo "${file#Skins/}" | cut -d/ -f1
                  done | sort -u
            )

            mapfile -t deleted_skins < <(
              git diff --name-only -z --diff-filter=D "$latest_tag" HEAD \
                | while IFS= read -r -d '' file; do
                    [[ $file == Skins/* ]] && echo "${file#Skins/}" | cut -d/ -f1
                  done | sort -u
            )
          else
            skins=("${all_skins[@]}")
          fi
        fi

        uniq_skins=()
        for skin in "${skins[@]}"; do
          skin="${skin#"${skin%%[![:space:]]*}"}"
          skin="${skin%"${skin##*[![:space:]]}"}"
          [[ -n "$skin" ]] && uniq_skins+=("$skin")
        done

        changed_skins_file="/tmp/changed_skins_$RANDOM.txt"

        if [ "${#uniq_skins[@]}" -eq 0 ]; then
          echo "[]" > "$changed_skins_file"
        else
          printf '%s\n' "${uniq_skins[@]}" | jq -R . | jq -cs . > "$changed_skins_file"
        fi

        {
          echo "changed_skins_file<<EOF"
          echo "$changed_skins_file"
          echo "EOF"
        } >> "$GITHUB_OUTPUT"