// CI/CD pipeline for supporthub-api.
//
// Stage order and guarantees are defined by:
//   - .specify/memory/constitution.md -> "Testing, Observability & CI/CD Gates"
//   - specs/001-ci-pipeline/contracts/pipeline-stage-contract.md
//
// Prerequisites (configured on the Jenkins side, never in this repo):
//   - Agents with Docker and Node.js 20+ available (label: 'docker && node20')
//   - Credentials (Secret text unless noted) per target environment <env> in [test, prod]:
//       <env>-postgres-password, <env>-redis-password, <env>-jwt-secret
//       <env>-aws-access-key-id, <env>-aws-secret-access-key
//     Plus one Username/Password credential: docker-registry-credentials
//   - A DOCKER_REGISTRY value (e.g. via a "CI_DOCKER_REGISTRY" global Jenkins env var,
//     or override the default below) pointing at the org's actual image registry.
//
// This file intentionally contains no secret values, only credential IDs — see
// specs/001-ci-pipeline/research.md "Environment/secrets handling in the pipeline".

pipeline {
    agent { label 'docker && node20' }

    options {
        timestamps()
        buildDiscarder(logRotator(numToKeepStr: '30'))
        // Each build gets its own workspace by default; Compose project names below are
        // additionally scoped by BUILD_NUMBER so concurrent runs never share containers,
        // networks, or volumes (FR-009 / SC-005).
        ansiColor('xterm')
    }

    environment {
        DOCKER_REGISTRY = "${env.CI_DOCKER_REGISTRY ?: 'registry.example.com/supporthub'}"
        IMAGE_NAME       = 'supporthub-api'
        COMPOSE_PROJECT  = "supporthub-ci-${env.BUILD_NUMBER}"
    }

    stages {

        stage('Checkout') {
            steps {
                checkout scm
            }
        }

        stage('Install') {
            steps {
                sh 'npm ci'
            }
        }

        stage('Environment validation') {
            steps {
                script {
                    resolveDeployTarget()
                    writeTargetEnvFile(env.TARGET_ENV == 'none' ? 'test' : env.TARGET_ENV)
                }
                // Reuses the existing Zod schema in src/config/env.ts as-is: it throws a
                // specific, descriptive error on safeParse failure, so this fails fast with
                // no new validation logic (FR-002).
                sh "npx tsx --env-file=.env.${env.TARGET_ENV == 'none' ? 'test' : env.TARGET_ENV} -e \"import('./src/config/env.ts').then(() => console.log('Environment OK'))\""
            }
        }

        stage('Generate Prisma client') {
            steps {
                sh 'npm run prisma:generate'
            }
        }

        stage('Typecheck') {
            steps {
                sh 'npm run typecheck'
            }
        }

        stage('Lint') {
            steps {
                sh 'npm run lint'
                // Enforces Constitution Principle III (module boundaries) server-side —
                // mirrors .husky/pre-commit so a bypassed/missing local hook can't merge
                // a boundary violation.
                sh 'npx tsx scripts/check-architecture.ts'
            }
        }

        stage('Format check') {
            steps {
                sh 'npm run format:check'
            }
        }

        stage('Unit test') {
            steps {
                sh 'npm run test:unit'
            }
        }

        stage('Integration test') {
            steps {
                sh "docker compose -p ${env.COMPOSE_PROJECT} --env-file .env.test -f docker-compose.test.yml up -d --wait postgres redis"
                sh "docker compose -p ${env.COMPOSE_PROJECT} --env-file .env.test -f docker-compose.test.yml run --rm --build app npm run test:integration"
            }
        }

        stage('E2E test') {
            steps {
                sh "docker compose -p ${env.COMPOSE_PROJECT} --env-file .env.test -f docker-compose.test.yml run --rm app npm run test:e2e"
            }
        }

        stage('Build') {
            steps {
                script {
                    def buildTarget = env.TARGET_ENV == 'none' ? 'test' : env.TARGET_ENV
                    sh "npm run build:${buildTarget}"
                }
            }
        }

        stage('Docker build') {
            steps {
                script {
                    def buildTarget = env.TARGET_ENV == 'none' ? 'test' : env.TARGET_ENV
                    env.IMAGE_TAG = "${env.DOCKER_REGISTRY}/${env.IMAGE_NAME}:${buildTarget}-${env.BUILD_NUMBER}"
                }
                sh "docker build --build-arg BUILD_COMMAND=\"npm run build:${env.TARGET_ENV == 'none' ? 'test' : env.TARGET_ENV}\" -t ${env.IMAGE_TAG} ."
            }
        }

        stage('Publish') {
            when { expression { env.TARGET_ENV != 'none' } }
            steps {
                withCredentials([usernamePassword(credentialsId: 'docker-registry-credentials',
                                                   usernameVariable: 'REGISTRY_USER',
                                                   passwordVariable: 'REGISTRY_PASSWORD')]) {
                    sh '''
                        echo "$REGISTRY_PASSWORD" | docker login "$DOCKER_REGISTRY" -u "$REGISTRY_USER" --password-stdin
                        docker push "$IMAGE_TAG"
                        docker logout "$DOCKER_REGISTRY"
                    '''
                }
            }
        }

        stage('Deploy') {
            when { expression { env.TARGET_ENV != 'none' } }
            steps {
                script {
                    writeTargetEnvFile(env.TARGET_ENV)
                }
                sh "docker compose --env-file .env.${env.TARGET_ENV} -f docker-compose.${env.TARGET_ENV == 'prod' ? 'prod' : 'test'}.yml up -d"
            }
        }
    }

    post {
        always {
            // Tear down the ephemeral integration/E2E stack regardless of outcome, and never
            // leave a generated .env.* file behind in the workspace. --env-file must be passed
            // to `down` too, or Compose can fail to resolve service config and leave containers
            // running (confirmed while validating this pipeline locally).
            sh "docker compose -p ${env.COMPOSE_PROJECT} --env-file .env.test -f docker-compose.test.yml down -v --remove-orphans || true"
            sh 'rm -f .env.test .env.prod .env.development'
            cleanWs()
        }
        failure {
            echo "Pipeline failed at stage: ${currentBuild.result}. See the failing stage's log above for the exact command and output — no local reproduction should be necessary (FR-004)."
        }
    }
}

// Resolves env.TARGET_ENV from the branch being built:
//   main            -> prod
//   develop/test    -> test
//   anything else   -> none (validate-only; Publish/Deploy stages are skipped, not failed)
void resolveDeployTarget() {
    def branch = env.BRANCH_NAME ?: ''
    if (branch == 'main') {
        env.TARGET_ENV = 'prod'
    } else if (branch == 'develop' || branch == 'test') {
        env.TARGET_ENV = 'test'
    } else {
        env.TARGET_ENV = 'none'
    }
    echo "Resolved deploy target for branch '${branch}': ${env.TARGET_ENV}"
}

// Writes .env.<target> into the workspace from Jenkins credentials — never read from a
// file committed to the repository (constitution governance: "secrets never committed").
void writeTargetEnvFile(String target) {
    withCredentials([
        string(credentialsId: "${target}-postgres-password", variable: 'POSTGRES_PASSWORD'),
        string(credentialsId: "${target}-redis-password", variable: 'REDIS_PASSWORD'),
        string(credentialsId: "${target}-jwt-secret", variable: 'JWT_SECRET'),
        string(credentialsId: "${target}-aws-access-key-id", variable: 'AWS_ACCESS_KEY_ID'),
        string(credentialsId: "${target}-aws-secret-access-key", variable: 'AWS_SECRET_ACCESS_KEY'),
    ]) {
        def port = target == 'prod' ? '4503' : (target == 'test' ? '4502' : '4501')
        def dbName = target == 'prod' ? 'myapp_prod' : (target == 'test' ? 'myapp_test' : 'support_dev')
        def dbUser = target == 'prod' ? 'myapp_prod' : (target == 'test' ? 'myapp_test' : 'support_user')
        writeFile file: ".env.${target}", text: """
NODE_ENV=${target == 'prod' ? 'production' : target}
PORT=${port}
BUILD_COMMAND=npm run build:${target}
POSTGRES_HOST=postgres
POSTGRES_DB=${dbName}
POSTGRES_USER=${dbUser}
POSTGRES_PASSWORD=${POSTGRES_PASSWORD}
DATABASE_URL=postgresql://${dbUser}:${POSTGRES_PASSWORD}@postgres:5432/${dbName}
REDIS_HOST=redis
REDIS_PORT=6379
REDIS_PASSWORD=${REDIS_PASSWORD}
JWT_SECRET=${JWT_SECRET}
AWS_ACCESS_KEY_ID=${AWS_ACCESS_KEY_ID}
AWS_SECRET_ACCESS_KEY=${AWS_SECRET_ACCESS_KEY}
CORS_ORIGINS=${target == 'prod' ? 'https://app.supporthub.com,https://admin.supporthub.com' : 'http://localhost:3000'}
""".stripIndent().trim()
    }
}