# Copyright 2019 Amazon.com, Inc. and its affiliates. All Rights Reserved.
#
# Licensed under the Amazon Software License (the 'License').
# You may not use this file except in compliance with the License.
# A copy of the License is located at
#
#   http://aws.amazon.com/asl/
#
# or in the 'license' file accompanying this file. This file is distributed
# on an 'AS IS' BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
# express or implied. See the License for the specific language governing
# permissions and limitations under the License.

AWSTemplateFormatVersion: "2010-09-09"
Description: "Create Lambda Function"

Resources:

#----------------------------------------------------------------------#
# EventRule to trigger CreatePipeline lambda
#----------------------------------------------------------------------#
  CreatePipelineRule:
    Type: AWS::Events::Rule
    Properties:
      Description: "EventRule"
      EventPattern:
        source:
          - aws.codecommit
        detail-type:
          - 'CodeCommit Repository State Change'
        detail:
          event:
              - referenceDeleted
              - referenceCreated
          referenceType:
            - branch
      State: ENABLED
      Targets:
      - Arn: !GetAtt CreatePipeline.Arn
        Id: CreatePipeline

  LambdaInvokePermission:
    Type: AWS::Lambda::Permission
    Properties:
      FunctionName: !Ref CreatePipeline
      Action: 'lambda:InvokeFunction'
      Principal: events.amazonaws.com
      SourceArn:
        Fn::GetAtt:
          - CreatePipelineRule
          - Arn


#----------------------------------------------------------------------#
# Role for lambda execution
#----------------------------------------------------------------------#
  LambdaRole:
    Type: AWS::IAM::Role
    Properties:
      RoleName: LambdaRole
      AssumeRolePolicyDocument:
        Version: 2012-10-17
        Statement:
          -
            Effect: Allow
            Principal:
              Service:
                - lambda.amazonaws.com
            Action:
              - sts:AssumeRole
      ManagedPolicyArns:
        - arn:aws:iam::aws:policy/AWSLambdaFullAccess
        - arn:aws:iam::aws:policy/AWSCloudFormationFullAccess
        - arn:aws:iam::aws:policy/AWSCodePipelineFullAccess
      Path: /


#----------------------------------------------------------------------#
# Role for Pipeline Execution
#----------------------------------------------------------------------#
  CodePipelineRole:
    Type: AWS::IAM::Role
    Properties:
      RoleName: CodePipelineRole
      ManagedPolicyArns:
        - arn:aws:iam::aws:policy/AWSCodePipelineFullAccess
        - arn:aws:iam::aws:policy/AWSCodeCommitFullAccess
        - arn:aws:iam::aws:policy/AWSCodeBuildDeveloperAccess
        - arn:aws:iam::aws:policy/AmazonS3FullAccess
      Path: /
      AssumeRolePolicyDocument:
        Version: 2012-10-17
        Statement:
          - Effect: Allow
            Principal:
              Service:
                - codepipeline.amazonaws.com
            Action:
              - 'sts:AssumeRole'



#----------------------------------------------------------------------#
# Role for CodeBuild Execution
#----------------------------------------------------------------------#
  CodeBuildRole:
    Type: AWS::IAM::Role
    Properties:
      RoleName: CodeBuildRole
      ManagedPolicyArns:
        - arn:aws:iam::aws:policy/AdministratorAccess
      Path: /
      AssumeRolePolicyDocument:
        Version: 2012-10-17
        Statement:
          - Effect: Allow
            Principal:
              Service:
                - codebuild.amazonaws.com
            Action:
              - 'sts:AssumeRole'


#----------------------------------------------------------------------#
# S3 Bucket to store template
#----------------------------------------------------------------------#
  TemplateBucket:
    Type: 'AWS::S3::Bucket'
    Properties:
      BucketName: !Sub ${AWS::AccountId}-templates

  TemplateBucketPolicy:
    Type: AWS::S3::BucketPolicy
    Properties:
      Bucket: !Ref TemplateBucket
      PolicyDocument:
        Statement:
          -
            Action:
                - s3:*
            Effect: Allow
            Resource:
              - !Sub arn:aws:s3:::${TemplateBucket}
              - !Sub arn:aws:s3:::${TemplateBucket}/*
            Principal:
              AWS:
                - !Sub arn:aws:iam::${AWS::AccountId}:root



#----------------------------------------------------------------------#
# Lambda for Stack Creation
#----------------------------------------------------------------------#
  CreatePipeline:
    DependsOn: LambdaRole
    Type: "AWS::Lambda::Function"
    Properties:
      FunctionName: CreatePipeline
      Handler: "index.lambda_handler"
      Role: !GetAtt LambdaRole.Arn
      Runtime: "python3.6"
      Timeout: 25
      Code:
        ZipFile: |
          import boto3
          def lambda_handler(event, context):
              Region=event['region']
              Account = event['account']
              RepositoryName = event['detail']['repositoryName']
              NewBranch = event['detail']['referenceName']
              Event = event['detail']['event']
              if NewBranch == "master":
                 quit()
              if Event == "referenceCreated":
                cf_client = boto3.client('cloudformation')
                cf_client.create_stack(
                    StackName= f'Pipeline-{RepositoryName}-{NewBranch}',
                    TemplateURL= f'https://s3.amazonaws.com/{Account}-templates/TemplatePipeline.yaml',
                    Parameters=[
                        {
                            'ParameterKey': 'RepositoryName',
                            'ParameterValue': RepositoryName,
                            'UsePreviousValue': False
                        },
                        {
                            'ParameterKey': 'BranchName',
                            'ParameterValue': NewBranch,
                            'UsePreviousValue': False
                        }
                    ],
                    OnFailure='ROLLBACK',
                    Capabilities=['CAPABILITY_NAMED_IAM']
                )
              else:
                cf_client = boto3.client('cloudformation')
                cf_client.delete_stack(
                    StackName= f'Pipeline-{RepositoryName}-{NewBranch}'
                  )