name: Build and Push Docker Images

on:
  push:
    branches: [main]
    paths:
      - 'images/**'
  workflow_dispatch:
    inputs:
      image:
        description: 'Image to build (e.g., terraform-ci)'
        required: false

env:
  REGISTRY: gitea.arnodo.fr

jobs:
  # ============================================================================
  # Job 1 : Detect modified images
  # ============================================================================
  detect-changes:
    runs-on: docker
    container:
      image: alpine:3.20
    outputs:
      matrix: ${{ steps.changes.outputs.matrix }}
      has_changes: ${{ steps.changes.outputs.has_changes }}
    steps:
      - name: Install dependencies
        run: apk add --no-cache git jq

      - name: Checkout repository
        run: |
          git clone --depth 2 https://gitea.arnodo.fr/${{ gitea.repository }}.git .
          git checkout ${{ gitea.sha }}

      - name: Detect changed images
        id: changes
        env:
          INPUT_IMAGE: ${{ inputs.image }}
        run: |
          # 1. Handle Manual Input
          if [ -n "$INPUT_IMAGE" ]; then
            # Clean input
            IMAGE=$(echo "$INPUT_IMAGE" | xargs)
            echo "DEBUG: Processing manual input image: '$IMAGE'"
            
            if [ -n "$IMAGE" ]; then
              if [ -d "images/$IMAGE" ] && [ -f "images/$IMAGE/Dockerfile" ]; then
                 echo "DEBUG: Image directory and Dockerfile exist."
                 # Use printf for safer output
                 printf "matrix=[\"%s\"]\n" "$IMAGE" >> $GITHUB_OUTPUT
                 echo "has_changes=true" >> $GITHUB_OUTPUT
                 echo "DEBUG: Set matrix=['$IMAGE']"
                 exit 0
              else
                 echo "Error: Image '$IMAGE' not found or missing Dockerfile at images/$IMAGE/Dockerfile"
                 echo "has_changes=false" >> $GITHUB_OUTPUT
                 echo "matrix=[]" >> $GITHUB_OUTPUT
                 exit 0
              fi
            else
               echo "DEBUG: Input image name was empty after trimming."
               echo "has_changes=false" >> $GITHUB_OUTPUT
               echo "matrix=[]" >> $GITHUB_OUTPUT
               exit 0
            fi
          fi

          # 2. Handle Automatic Detection (Git Diff)
          echo "DEBUG: Running git diff detection..."
          > valid_images.txt
          
          CHANGED_FILES=$(git diff --name-only HEAD~1 HEAD -- images/ 2>/dev/null || true)
          
          CANDIDATES=$(echo "$CHANGED_FILES" | cut -d'/' -f2 | sort -u | grep -v '^$')
          
          for CANDIDATE in $CANDIDATES; do
            if [ -d "images/$CANDIDATE" ] && [ -f "images/$CANDIDATE/Dockerfile" ]; then
              echo "$CANDIDATE" >> valid_images.txt
            fi
          done
          
          if [ ! -s valid_images.txt ]; then
             echo "No valid images detected."
             echo "has_changes=false" >> $GITHUB_OUTPUT
             echo "matrix=[]" >> $GITHUB_OUTPUT
          else
             # Convert list to JSON array using jq
             JSON=$(cat valid_images.txt | jq -R -s -c 'split("\n") | map(select(length > 0))')
             echo "Detected images: $JSON"
             echo "matrix=$JSON" >> $GITHUB_OUTPUT
             echo "has_changes=true" >> $GITHUB_OUTPUT
          fi

      - name: Show detected changes
        run: |
          echo "Matrix: ${{ steps.changes.outputs.matrix }}"
          echo "Has changes: ${{ steps.changes.outputs.has_changes }}"

  # ============================================================================
  # Job 2 : Build and Push (Standard Docker)
  # ============================================================================
  build:
    needs: detect-changes
    if: needs.detect-changes.outputs.has_changes == 'true'
    runs-on: docker
    container:
      image: docker:cli
    strategy:
      matrix:
        image: ${{ fromJson(needs.detect-changes.outputs.matrix) }}
      fail-fast: false
    steps:
      - name: Install dependencies
        run: apk add --no-cache git

      - name: Checkout repository
        run: |
          git clone --depth 2 https://gitea.arnodo.fr/${{ gitea.repository }}.git .
          git checkout ${{ gitea.sha }}

      - name: Login to Registry
        run: |
          echo "${{ secrets.REGISTRY_TOKEN }}" | docker login ${{ env.REGISTRY }} -u ${{ gitea.actor }} --password-stdin

      - name: Build and Push
        env:
          IMAGE_NAME: ${{ env.REGISTRY }}/damien/${{ matrix.image }}
          IMAGE_PATH: images/${{ matrix.image }}
        run: |
          echo "Debug: Matrix Image is '${{ matrix.image }}'"
          
          if [ -z "${{ matrix.image }}" ]; then
            echo "Skipping empty image name"
            exit 0
          fi

          echo "Building $IMAGE_NAME:latest from $IMAGE_PATH ..."
          
          if [ ! -d "$IMAGE_PATH" ]; then
            echo "Error: Directory $IMAGE_PATH does not exist."
            exit 1
          fi
          
          if [ ! -f "$IMAGE_PATH/Dockerfile" ]; then
            echo "Error: Dockerfile not found in $IMAGE_PATH."
            exit 1
          fi

          # Use standard docker build
          docker build -t "$IMAGE_NAME:latest" "$IMAGE_PATH"
          docker push "$IMAGE_NAME:latest"
          
          echo "✅ Pushed $IMAGE_NAME:latest"