---
- name: Rollback ECS Service
  hosts: localhost
  connection: local
  gather_facts: false
  vars:
    ecs_cluster_name: "nvhi-atsila-cluster"
    service_name: "nvhi-atsila-cluster-service"
    task_family: "nvhi-atsila-cluster-task"
    aws_region: "us-east-2"
    
  tasks:
    - name: Get current service task definition
      shell: |
        aws ecs describe-services \
          --cluster {{ ecs_cluster_name }} \
          --services {{ service_name }} \
          --region {{ aws_region }} \
          --query 'services[0].taskDefinition' \
          --output text
      register: current_task_def
      environment:
        AWS_DEFAULT_REGION: "{{ aws_region }}"

    - name: Extract current revision number
      set_fact:
        current_revision: "{{ current_task_def.stdout.split(':')[-1] | int }}"

    - name: Calculate rollback revision
      set_fact:
        rollback_revision: "{{ (current_revision | int) - 1 }}"
      when: rollback_revision is not defined

    - name: Validate rollback revision
      fail:
        msg: "Cannot rollback - target revision {{ rollback_revision }} is invalid (must be >= 1)"
      when: (rollback_revision | int) < 1

    - name: Display rollback information
      debug:
        msg: |
          =================================
          ROLLBACK INFORMATION
          =================================
          Service: {{ service_name }}
          Cluster: {{ ecs_cluster_name }}
          Current Revision: {{ current_revision }}
          Target Revision: {{ rollback_revision }}
          =================================

    - name: Confirm rollback (interactive)
      pause:
        prompt: |
          WARNING: You are about to rollback the ECS service!
          
          Service: {{ service_name }}
          From: {{ task_family }}:{{ current_revision }}
          To: {{ task_family }}:{{ rollback_revision }}
          
          Do you want to continue? (yes/no)
      register: rollback_confirm
      when: auto_rollback is not defined

    - name: Set automatic confirmation
      set_fact:
        rollback_confirm:
          user_input: "yes"
      when: auto_rollback is defined and auto_rollback

    - name: Execute rollback
      shell: |
        aws ecs update-service \
          --cluster {{ ecs_cluster_name }} \
          --service {{ service_name }} \
          --task-definition {{ task_family }}:{{ rollback_revision }} \
          --force-new-deployment \
          --region {{ aws_region }} \
          --output json
      environment:
        AWS_DEFAULT_REGION: "{{ aws_region }}"
      when: rollback_confirm.user_input | lower == 'yes'
      register: rollback_result

    - name: Wait for rollback completion
      shell: |
        echo "Waiting for rollback to complete..."
        count=0
        while [ $count -lt 20 ]; do
          service_status=$(aws ecs describe-services \
            --cluster {{ ecs_cluster_name }} \
            --services {{ service_name }} \
            --region {{ aws_region }} \
            --query 'services[0]' \
            --output json 2>/dev/null)
          
          if [ $? -eq 0 ]; then
            running=$(echo "$service_status" | jq -r '.runningCount // 0')
            pending=$(echo "$service_status" | jq -r '.pendingCount // 0')
            
            echo "Running: $running, Pending: $pending"
            
            if [ "$running" -ge "1" ] && [ "$pending" -eq "0" ]; then
              echo "Rollback completed successfully"
              exit 0
            fi
          fi
          
          echo "Waiting for rollback completion (attempt $((count+1))/20)..."
          sleep 15
          count=$((count+1))
        done
        
        echo "WARNING: Rollback may not have completed within expected time"
        exit 1
      environment:
        AWS_DEFAULT_REGION: "{{ aws_region }}"
      when: rollback_confirm.user_input | lower == 'yes'

    - name: Verify rollback status
      shell: |
        aws ecs describe-services \
          --cluster {{ ecs_cluster_name }} \
          --services {{ service_name }} \
          --region {{ aws_region }} \
          --query 'services[0].{TaskDefinition:taskDefinition,RunningCount:runningCount,Status:status}' \
          --output table
      environment:
        AWS_DEFAULT_REGION: "{{ aws_region }}"
      when: rollback_confirm.user_input | lower == 'yes'
      register: final_status

    - name: Display rollback results
      debug:
        msg: |
          ========================================
          🔄 ROLLBACK COMPLETED
          ========================================
          Service: {{ service_name }}
          Rolled back to: {{ task_family }}:{{ rollback_revision }}
          Status: Check output above
          ========================================
      when: rollback_confirm.user_input | lower == 'yes'

    - name: Rollback cancelled
      debug:
        msg: "Rollback operation was cancelled by user"
      when: rollback_confirm.user_input | lower != 'yes'