def setupCC(failOnError = true) {
    errorStr = failOnError ? "-Werror " : ""
    "echo CC=${env.CXX} ${errorStr}> make/local"
}

def setup(String pr, Boolean failOnError = true) {
    script = """
        make math-revert
        make clean-all
        git clean -xffd
        ${setupCC(failOnError)}
    """
    if (pr != '')  {
        prNumber = pr.tokenize('-').last()
        script += """ 
            cd lib/stan_math
            git fetch https://github.com/stan-dev/math +refs/pull/${prNumber}/merge:refs/remotes/origin/pr/${prNumber}/merge
            git checkout refs/remotes/origin/pr/${prNumber}/merge
        """
    }
    return script
}

def mailBuildResults(String label, additionalEmails='') {
    emailext (
        subject: "[StanJenkins] ${label}: Job '${env.JOB_NAME} [${env.BUILD_NUMBER}]'",
        body: """${label}: Job '${env.JOB_NAME} [${env.BUILD_NUMBER}]': Check console output at ${env.BUILD_URL}""",
        recipientProviders: [[$class: 'RequesterRecipientProvider']],
        to: "${env.CHANGE_AUTHOR_EMAIL}, ${additionalEmails}"
    )
}

def runTests(String testPath) {
    "runTests.py -j${env.PARALLEL} ${testPath} || echo ${testPath} failed"
}

def updateUpstream(String upstreamRepo) {
    if (env.BRANCH_NAME == 'develop') {
        node('master') {
            retry(3) {
                checkout([$class: 'GitSCM',
                        branches: [[name: '*/develop']],
                        doGenerateSubmoduleConfigurations: false,
                        extensions: [[$class: 'SubmoduleOption',
                                    disableSubmodules: false,
                                    parentCredentials: false,
                                    recursiveSubmodules: true,
                                    reference: '',
                                    trackingSubmodules: false]],
                        submoduleCfg: [],
                        userRemoteConfigs: [[url: 'git@github.com:stan-dev/cmdstan.git',
                                           credentialsId: 'a630aebc-6861-4e69-b497-fd7f496ec46b'
                ]]])
            }
            sh """
                curl -O https://raw.githubusercontent.com/stan-dev/ci-scripts/master/jenkins/create-${upstreamRepo}-pull-request.sh
                sh create-${upstreamRepo}-pull-request.sh
            """
            deleteDir()
        }
    }
}

pipeline {
    agent none
    parameters {
        string(defaultValue: '', name: 'math_pr', description: "Leave blank "
                + "unless testing against a specific math repo pull request, "
                + "e.g. PR-640.")
        string(defaultValue: 'downstream tests', name: 'cmdstan_pr',
          description: 'PR to test CmdStan upstream against e.g. PR-630')
    }
    options { skipDefaultCheckout() }
    stages {
        stage('Linting & Doc checks') {
            agent any
            steps {
                script {
                    retry(3) { checkout scm }
                    sh setup(params.math_pr)
                    stash 'StanSetup'
                    parallel(
                        CppLint: { sh "make cpplint" },
                        documentation: { sh 'make doxygen' },
                        manual: { sh 'make manual' },
                        headers: { sh "make -j${env.PARALLEL} test-headers" },
                        failFast: true
                    )
                }
            }
            post { always { deleteDir() } }
        }
        stage('Tests') {
            failFast true
            parallel {
                stage('Windows Unit') {
                    agent { label 'windows' }
                    steps {
                        unstash 'StanSetup'
                        bat setupCC(false)
                        bat runTests("src/test/unit")
                        retry(2) { junit 'test/unit/**/*.xml' }
                    }
                    post { always { deleteDir() } }
                }
                stage('Windows Headers') { 
                    agent { label 'windows' }
                    steps {
                        unstash 'StanSetup'
                        bat setupCC()
                        bat "make -j${env.PARALLEL} test-headers"
                    }
                    post { always { deleteDir() } }
                }
                stage('Unit') { 
                    agent any
                    steps {
                        unstash 'StanSetup'
                        sh setupCC(false)
                        sh "./" + runTests("src/test/unit")
                        retry(2) { junit 'test/unit/**/*.xml' }
                    }
                    post { always { deleteDir() } }
                }
                stage('Integration') {
                    agent any
                    steps { 
                        unstash 'StanSetup'
                        sh setupCC()
                        sh "./" + runTests("src/test/integration")
                        retry(2) { junit 'test/integration/*.xml' }
                    }
                    post { always { deleteDir() } }
                }
                stage('Upstream CmdStan tests') {
                    // These will only execute when we're running against the
                    // live PR build, not on other branches
                    when { expression { env.BRANCH_NAME ==~ /PR-\d+/ } }
                    steps {
                        build(job: "CmdStan/${params.cmdstan_pr}",
                              parameters: [string(name: 'stan_pr', value: env.BRANCH_NAME),
                                           string(name: 'math_pr', value: params.math_pr)])
                    }
                }
            }
        }
        stage('Performance') {
            agent { label 'gelman-group-mac' }
            steps {
                unstash 'StanSetup'
                sh setupCC()
                sh """
                    ./runTests.py -j${env.PARALLEL} src/test/performance
                    cd test/performance
                    RScript ../../src/test/performance/plot_performance.R 
                """
            }
            post {
                always {
                    retry(2) {
                        junit 'test/**/*.xml'
                        archiveArtifacts 'test/performance/performance.csv,test/performance/performance.png'
                        perfReport compareBuildPrevious: true, errorFailedThreshold: 0, errorUnstableThreshold: 0, failBuildIfNoResultFile: false, modePerformancePerTestCase: true, sourceDataFiles: 'test/performance/**.xml'
                    }
                    deleteDir()
                }
            }
        }
    }
    post {
        always {
            node('master') {
                warnings consoleParsers: [[parserName: 'CppLint']], canRunOnFailed: true
                warnings consoleParsers: [[parserName: 'GNU C Compiler 4 (gcc)']], canRunOnFailed: true
                warnings consoleParsers: [[parserName: 'Clang (LLVM based)']], canRunOnFailed: true
            }
        }
        success {
            updateUpstream('cmdstan')
            mailBuildResults("SUCCESSFUL")
        }
        unstable { mailBuildResults("UNSTABLE", "stan-buildbot@googlegroups.com") }
        failure { mailBuildResults("FAILURE", "stan-buildbot@googlegroups.com") }
    }
}