def counts = 0
def projects2artifacts = [:]
def artifacts2projects = [:]
def modules2deps = [:]
def inputProject = params.jenkins_project
def report = [:]
report['project'] = inputProject

pipeline {
    agent {
        label 'CD'
    }
    parameters {
        string(name: 'jenkins_project',
                    defaultValue: '',
                    description: 'The name of the Jenkins project to analyze.')
    }
    stages {

        stage('walking projects') {
            steps {
               script {
                    Jenkins.getInstance().getAllItems(TopLevelItem.class).each { p ->
                            projects2artifacts[p.name] = []
                            p.getAllJobs().each { j -> projects2artifacts[p.name] << j.name; artifacts2projects[j.name] = p.name }
                    }
                    println "FOUND ${projects2artifacts.size()} projects"
                    //projects2artifacts.each { k,v -> println ("PROJECT ${k} BUILDS ${v}") }
               }
            }
        }

        stage('walking maven modules') {
            steps {
                script {
                    // get all the maven modules and their dependencies
                    Jenkins.getInstance().getAllItems(hudson.maven.MavenModule.class).each { m ->
                            modules2deps[m.name] = []
                            m.getDependencies().each { d -> modules2deps[m.name] << "${d.groupId}:${d.artifactId}" }
                    }
                    println "FOUND ${modules2deps.size()} modules"
                    //modules2deps.each { k,v -> println ("MODULE ${k} DEPENDS on ${v}") }
                }
            }
        }

        stage('analyze downstream projects') {
                steps {
                    script {
                          // println "PROJECT ${inputProject} BUILDS ${projects2artifacts[inputProject]} artifacts"
                          // first, let's find out what components depends on the project's artifacts (i.e. downstream dependencies)
                          def downstreamdeps = [:]
                          report['downstream_modules'] = [:]
                          report['downstream_projects'] = []
                          report['downstream_modules']['L1'] = [:]
                          projects2artifacts[inputProject].each { a -> report = analyzeDependency(modules2deps, artifacts2projects, report, a, 1)}

                    }
                }
            }

        stage('print report') {
            steps {
                script {
                    printReport(report)
                }
            }
        }
   }

}
// look for modules that use this artifact
def findDownstreamDependencies(modules2deps, artifact) {
    def downdeps = []
    //println "Looking for users of ${artifact}"
    modules2deps.each { k,v -> if (v.contains("${artifact}")) downdeps << k }
    downdeps
}

//build the report of the given dependency, go recursive on its dependencies
def analyzeDependency(modules2deps, artifacts2projects, report, artifact, deep) {
    def level = "L${deep}"
    report['downstream_modules'][level][artifact] = [ 'dependencies':[], 'projects':[] ]

    // get all downstream dependencies
    report['downstream_modules'][level][artifact]['dependencies'].addAll(findDownstreamDependencies(modules2deps, artifact))
    //println "${artifact} is used by ${report['downstream_modules'][level][artifact]['dependencies']}"

    // add the project that builds the artifact
    report['downstream_modules'][level][artifact]['projects'] << artifacts2projects[artifact]
    report['downstream_projects'] <<  artifacts2projects[artifact]

    // then we look for the projects that build the downstream dependencies and finally we go recursive
    if (report['downstream_modules'][level][artifact]['dependencies']) {
        def nextDeep = ++deep
        report['downstream_modules']["L${nextDeep}"] = [:]
        report['downstream_modules'][level][artifact]['dependencies'].each { d ->
            report['downstream_modules'][level][artifact]['projects'] << artifacts2projects[d]
            report['downstream_projects'] <<  artifacts2projects[d]
            // go recursive
            analyzeDependency(modules2deps, artifacts2projects, report, d, nextDeep)
        }
    }
    report
}

// print the final report
def printReport(report) {
    def text = ''
    def indent = '\t'
    text += "Dependency Report for ${report['project']} (jenkins project)"
    text += "\n\n"
    text += "|--Project Modules\n"
    report['downstream_modules'].each { deep, artifacts ->
            artifacts.each { name, data ->
                text += "${indent}|--Module Name: ${name}\n"
                text += "${indent}|--Dependency Level: ${deep}\n"
                text += "${indent}|--Downstream Modules for ${name}\n"
                data['dependencies'].each {d ->
                    text += "${indent}\t|--${d}"
                    text += "\n"
                }
                text += "${indent}|--Downstream Projects for ${name}\n"
                data['projects'].each { p ->
                     text += "${indent}\t|--${p}"
                     text += "\n"
                }
            }
     }

    text += "\n\n"
    text += "|--All Downstream Projects\n"
    report['downstream_projects'].unique().sort()
    report['downstream_projects'].each { p ->
         text += "${indent}|--${p}"
         text += "\n"
    }
    println text
}
// debug job
def printJob(job) {
       println("fullname ${job.fullName}")
       println("name ${job.name}")
       println("display name ${job.displayName}")
       job.getAllJobs().each {j -> println ("dep: ${j.name}")}
}