# =========================================================================================
# Copyright (C) 2024 Pierre Smeyers and contributors
#
# This program is free software; you can redistribute it and/or modify it under the terms 
# of the GNU Lesser General Public License as published by the Free Software Foundation; 
# either version 3 of the License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
# without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
# See the GNU Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public License along with this 
# program; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth 
# Floor, Boston, MA  02110-1301, USA.
# =========================================================================================
spec:
  inputs:

    image:
      description: The Docker image used to run `cargo`
      default: docker.io/rust:1.2.3
    build-args:
      description: Arguments used by the build job
      default: build --with-default-args
    lint-disabled:
      description: Disable RUST lint
      type: boolean
      default: false
    lint-image:
      description: The Docker image used to run the lint tool
      default: docker.io/rust-lint:latest
    lint-args:
      description: Lint [options and arguments](link-to-the-cli-options)
      default: --serevity=medium
    depcheck-image:
      description: The Docker image used to run the dependency check tool
      default: docker.io/rust-depcheck:latest
    depcheck-args:
      description: Dependency check [options and arguments](link-to-the-cli-options)
      default: ''
    publish-enabled:
      description: Enable Publish
      type: boolean
      default: false
    publish-args:
      description: Arguments used by the publish job
      default: publish --with-default-args
    rust-build-job-tags:
      description: tags to filter applicable runners for rust-build job
      type: array
      default: []
    rust-lint-job-tags:
      description: tags to filter applicable runners for rust-lint job
      type: array
      default: []
    rust-depcheck-job-tags:
      description: tags to filter applicable runners for rust-depcheck job
      type: array
      default: []
    rust-publish-job-tags:
      description: tags to filter applicable runners for rust-publish job
      type: array
      default: []

---
# default workflow rules: Merge Request pipelines
workflow:
  rules:
    # prevent MR pipeline originating from production or integration branch(es)
    - if: '$CI_MERGE_REQUEST_SOURCE_BRANCH_NAME =~ $PROD_REF || $CI_MERGE_REQUEST_SOURCE_BRANCH_NAME =~ $INTEG_REF'
      when: never
    # on non-prod, non-integration branches: prefer MR pipeline over branch pipeline
    - if: '$CI_COMMIT_BRANCH && $CI_OPEN_MERGE_REQUESTS && $CI_COMMIT_REF_NAME !~ $PROD_REF && $CI_COMMIT_REF_NAME !~ $INTEG_REF'
      when: never
    - if: '$CI_COMMIT_MESSAGE =~ "/\[(ci skip|skip ci) on ([^],]*,)*tag(,[^],]*)*\]/" && $CI_COMMIT_TAG'
      when: never
    - if: '$CI_COMMIT_MESSAGE =~ "/\[(ci skip|skip ci) on ([^],]*,)*branch(,[^],]*)*\]/" && $CI_COMMIT_BRANCH'
      when: never
    - if: '$CI_COMMIT_MESSAGE =~ "/\[(ci skip|skip ci) on ([^],]*,)*mr(,[^],]*)*\]/" && $CI_MERGE_REQUEST_ID'
      when: never
    - if: '$CI_COMMIT_MESSAGE =~ "/\[(ci skip|skip ci) on ([^],]*,)*default(,[^],]*)*\]/" && $CI_COMMIT_REF_NAME =~ $CI_DEFAULT_BRANCH'
      when: never
    - if: '$CI_COMMIT_MESSAGE =~ "/\[(ci skip|skip ci) on ([^],]*,)*prod(,[^],]*)*\]/" && $CI_COMMIT_REF_NAME =~ $PROD_REF'
      when: never
    - if: '$CI_COMMIT_MESSAGE =~ "/\[(ci skip|skip ci) on ([^],]*,)*integ(,[^],]*)*\]/" && $CI_COMMIT_REF_NAME =~ $INTEG_REF'
      when: never
    - if: '$CI_COMMIT_MESSAGE =~ "/\[(ci skip|skip ci) on ([^],]*,)*dev(,[^],]*)*\]/" && $CI_COMMIT_REF_NAME !~ $PROD_REF && $CI_COMMIT_REF_NAME !~ $INTEG_REF'
      when: never
    - when: always

# test job prototype: implement adaptive pipeline rules
.test-policy:
  rules:
    # on tag: auto & failing
    - if: $CI_COMMIT_TAG
    # on ADAPTIVE_PIPELINE_DISABLED: auto & failing
    - if: '$ADAPTIVE_PIPELINE_DISABLED == "true"'
    # on production or integration branch(es): auto & failing
    - if: '$CI_COMMIT_REF_NAME =~ $PROD_REF || $CI_COMMIT_REF_NAME =~ $INTEG_REF'
    # early stage (dev branch, no MR): manual & non-failing
    - if: '$CI_MERGE_REQUEST_ID == null && $CI_OPEN_MERGE_REQUESTS == null'
      when: manual
      allow_failure: true
    # Draft MR: auto & non-failing
    - if: '$CI_MERGE_REQUEST_TITLE =~ /^Draft:.*/'
      allow_failure: true
    # else (Ready MR): auto & failing
    - when: on_success

variables:
  # variabilized tracking image
  TBC_TRACKING_IMAGE: registry.gitlab.com/to-be-continuous/tools/tracking:master

  # Default Docker image (use a public image - can be overridden)
  RUST_IMAGE: $[[ inputs.image ]]

  RUST_BUILD_ARGS: $[[ inputs.build-args ]]

  RUST_PUBLISH_ENABLED: $[[ inputs.publish-enabled ]]
  RUST_PUBLISH_ARGS: $[[ inputs.publish-args ]]

  RUST_LINT_DISABLED: $[[ inputs.lint-disabled ]]
  RUST_LINT_IMAGE: $[[ inputs.lint-image ]]
  RUST_LINT_ARGS: $[[ inputs.lint-args ]]

  RUST_DEPCHECK_IMAGE: $[[ inputs.depcheck-image ]]
  RUST_DEPCHECK_ARGS: $[[ inputs.depcheck-args ]]

  # default production ref name (pattern)
  PROD_REF: '/^(master|main)$/'
  # default integration ref name (pattern)
  INTEG_REF: '/^develop$/'

stages:
  - build
  - test
  - package-build
  - package-test
  - infra
  - deploy
  - acceptance
  - publish
  - infra-prod
  - production

.rust-scripts: &rust-scripts |
  # BEGSCRIPT
  set -e

  function log_info() {
    >&2 echo -e "[\\e[1;94mINFO\\e[0m] $*"
  }

  function log_warn() {
    >&2 echo -e "[\\e[1;93mWARN\\e[0m] $*"
  }

  function log_error() {
    >&2 echo -e "[\\e[1;91mERROR\\e[0m] $*"
  }

  function fail() {
    log_error "$*"
    exit 1
  }

  function assert_defined() {
    if [[ -z "$1" ]]
    then
      log_error "$2"
      exit 1
    fi
  }

  function install_ca_certs() {
    certs=$1
    if [[ -z "$certs" ]]
    then
      return
    fi

    # List of typical bundles
    bundles="/etc/ssl/certs/ca-certificates.crt"                            # Debian/Ubuntu/Gentoo etc.
    bundles="${bundles} /etc/ssl/cert.pem"                                  # Alpine Linux
    bundles="${bundles} /etc/pki/ca-trust/extracted/pem/tls-ca-bundle.pem"  # CentOS/RHEL 7
    bundles="${bundles} /etc/pki/tls/certs/ca-bundle.crt"                   # Fedora/RHEL 6
    bundles="${bundles} /etc/ssl/ca-bundle.pem"                             # OpenSUSE
    bundles="${bundles} /etc/pki/tls/cacert.pem"                            # OpenELEC

    # Try to find the right bundle to update it with custom CA certificates
    for bundle in ${bundles}
    do
      # import if bundle exists
      if [[ -f "${bundle}" ]]
      then
        # Import certificates in bundle
        echo "${certs}" | tr -d '\r' >> "${bundle}"

        log_info "Custom CA certificates imported in \\e[33;1m${bundle}\\e[0m"
        ca_imported=1
        break
      fi
    done

    if [[ -z "$ca_imported" ]]
    then
      log_warn "Could not import custom CA certificates !"
    fi
  }

  function unscope_variables() {
    _scoped_vars=$(env | awk -F '=' "/^scoped__[a-zA-Z0-9_]+=/ {print \$1}" | sort)
    if [[ -z "$_scoped_vars" ]]; then return; fi
    log_info "Processing scoped variables..."
    for _scoped_var in $_scoped_vars
    do
      _fields=${_scoped_var//__/:}
      _condition=$(echo "$_fields" | cut -d: -f3)
      case "$_condition" in
      if) _not="";;
      ifnot) _not=1;;
      *)
        log_warn "... unrecognized condition \\e[1;91m$_condition\\e[0m in \\e[33;1m${_scoped_var}\\e[0m"
        continue
      ;;
      esac
      _target_var=$(echo "$_fields" | cut -d: -f2)
      _cond_var=$(echo "$_fields" | cut -d: -f4)
      _cond_val=$(eval echo "\$${_cond_var}")
      _test_op=$(echo "$_fields" | cut -d: -f5)
      case "$_test_op" in
      defined)
        if [[ -z "$_not" ]] && [[ -z "$_cond_val" ]]; then continue; 
        elif [[ "$_not" ]] && [[ "$_cond_val" ]]; then continue; 
        fi
        ;;
      equals|startswith|endswith|contains|in|equals_ic|startswith_ic|endswith_ic|contains_ic|in_ic)
        # comparison operator
        # sluggify actual value
        _cond_val=$(echo "$_cond_val" | tr '[:punct:]' '_')
        # retrieve comparison value
        _cmp_val_prefix="scoped__${_target_var}__${_condition}__${_cond_var}__${_test_op}__"
        _cmp_val=${_scoped_var#"$_cmp_val_prefix"}
        # manage 'ignore case'
        if [[ "$_test_op" == *_ic ]]
        then
          # lowercase everything
          _cond_val=$(echo "$_cond_val" | tr '[:upper:]' '[:lower:]')
          _cmp_val=$(echo "$_cmp_val" | tr '[:upper:]' '[:lower:]')
        fi
        case "$_test_op" in
        equals*)
          if [[ -z "$_not" ]] && [[ "$_cond_val" != "$_cmp_val" ]]; then continue; 
          elif [[ "$_not" ]] && [[ "$_cond_val" == "$_cmp_val" ]]; then continue; 
          fi
          ;;
        startswith*)
          if [[ -z "$_not" ]] && [[ "$_cond_val" != "$_cmp_val"* ]]; then continue; 
          elif [[ "$_not" ]] && [[ "$_cond_val" == "$_cmp_val"* ]]; then continue; 
          fi
          ;;
        endswith*)
          if [[ -z "$_not" ]] && [[ "$_cond_val" != *"$_cmp_val" ]]; then continue; 
          elif [[ "$_not" ]] && [[ "$_cond_val" == *"$_cmp_val" ]]; then continue; 
          fi
          ;;
        contains*)
          if [[ -z "$_not" ]] && [[ "$_cond_val" != *"$_cmp_val"* ]]; then continue; 
          elif [[ "$_not" ]] && [[ "$_cond_val" == *"$_cmp_val"* ]]; then continue; 
          fi
          ;;
        in*)
          if [[ -z "$_not" ]] && [[ "__${_cmp_val}__" != *"__${_cond_val}__"* ]]; then continue; 
          elif [[ "$_not" ]] && [[ "__${_cmp_val}__" == *"__${_cond_val}__"* ]]; then continue; 
          fi
          ;;
        esac
        ;;
      *)
        log_warn "... unrecognized test operator \\e[1;91m${_test_op}\\e[0m in \\e[33;1m${_scoped_var}\\e[0m"
        continue
        ;;
      esac
      # matches
      _val=$(eval echo "\$${_target_var}")
      log_info "... apply \\e[32m${_target_var}\\e[0m from \\e[32m\$${_scoped_var}\\e[0m${_val:+ (\\e[33;1moverwrite\\e[0m)}"
      _val=$(eval echo "\$${_scoped_var}")
      export "${_target_var}"="${_val}"
    done
    log_info "... done"
  }

  # evaluate and export a secret
  # - $1: secret variable name
  function eval_secret() {
    name=$1
    value=$(eval echo "\$${name}")
    case "$value" in
    @b64@*)
      decoded=$(mktemp)
      errors=$(mktemp)
      if echo "$value" | cut -c6- | base64 -d > "${decoded}" 2> "${errors}"
      then
        # shellcheck disable=SC2086
        export ${name}="$(cat ${decoded})"
        log_info "Successfully decoded base64 secret \\e[33;1m${name}\\e[0m"
      else
        fail "Failed decoding base64 secret \\e[33;1m${name}\\e[0m:\\n$(sed 's/^/... /g' "${errors}")"
      fi
      ;;
    @hex@*)
      decoded=$(mktemp)
      errors=$(mktemp)
      if echo "$value" | cut -c6- | sed 's/\([0-9A-F]\{2\}\)/\\\\x\1/gI' | xargs printf > "${decoded}" 2> "${errors}"
      then
        # shellcheck disable=SC2086
        export ${name}="$(cat ${decoded})"
        log_info "Successfully decoded hexadecimal secret \\e[33;1m${name}\\e[0m"
      else
        fail "Failed decoding hexadecimal secret \\e[33;1m${name}\\e[0m:\\n$(sed 's/^/... /g' "${errors}")"
      fi
      ;;
    @url@*)
      url=$(echo "$value" | cut -c6-)
      if command -v curl > /dev/null
      then
        decoded=$(mktemp)
        errors=$(mktemp)
        if curl -s -S -f --connect-timeout 5 -o "${decoded}" "$url" 2> "${errors}"
        then
          # shellcheck disable=SC2086
          export ${name}="$(cat ${decoded})"
          log_info "Successfully curl'd secret \\e[33;1m${name}\\e[0m"
        else
          log_warn "Failed getting secret \\e[33;1m${name}\\e[0m:\\n$(sed 's/^/... /g' "${errors}")"
        fi
      elif command -v wget > /dev/null
      then
        decoded=$(mktemp)
        errors=$(mktemp)
        if wget -T 5 -O "${decoded}" "$url" 2> "${errors}"
        then
          # shellcheck disable=SC2086
          export ${name}="$(cat ${decoded})"
          log_info "Successfully wget'd secret \\e[33;1m${name}\\e[0m"
        else
          log_warn "Failed getting secret \\e[33;1m${name}\\e[0m:\\n$(sed 's/^/... /g' "${errors}")"
        fi
      else
        fail "Couldn't get secret \\e[33;1m${name}\\e[0m: no http client found"
      fi
      ;;
    esac
  }

  function eval_all_secrets() {
    encoded_vars=$(env | grep -v '^scoped__' | awk -F '=' '/^[a-zA-Z0-9_]*=@(b64|hex|url)@/ {print $1}')
    for var in $encoded_vars
    do
      eval_secret "$var"
    done
  }

  function maybe_exec_hook() {
    if [[ -f "$1" ]]
    then
      log_info "\\e[33;1m$1\\e[0m hook found: execute"
      if [[ ! -x "$1" ]] && ! chmod +x "$1"
      then
        log_warn "... could not make \\e[33;1m${1}\\e[0m executable: please do it (chmod +x)"
        # fallback technique
        sh "$1"
      else
        "$1"
      fi
    fi
  }

  function output_coverage() {
    echo "[TODO]: compute and output global coverage result"
    echo "11% covered"
  }

  unscope_variables
  eval_all_secrets

  # ENDSCRIPT

# job prototype
# defines default Docker image, tracking probe, cache policy and tags
.rust-base:
  image: $RUST_IMAGE
  services:
    - name: "$TBC_TRACKING_IMAGE"
      command: ["--service", "rust", "1.0.0"]
  before_script:
    - !reference [.rust-scripts]
    - install_ca_certs "${CUSTOM_CA_CERTS:-$DEFAULT_CA_CERTS}"
  variables:
    # TODO (if necessary): set cache dir variables
    XDG_CACHE_HOME: "$CI_PROJECT_DIR/.cache"
  cache:
    # cache shall be per branch per template
    key: "${CI_COMMIT_REF_SLUG}-rust"
    fallback_keys:
      - "${CI_DEFAULT_BRANCH}-rust"
    when: always
    # cache shall be per branch per template
    key: "$CI_COMMIT_REF_SLUG-rust"
    when: always
    paths:
      - .cache/

# (example) build & test job
rust-build:
  extends: .rust-base
  stage: build
  script:
    - mkdir -p -m 777 reports
    # TODO (if possible): $TRACE set enables debug logs on the tool
    # TODO (if possible): force test tool to produce JUnit report(s)
    # TODO (if possible): force test tool to compute code coverage with report
    - cargo ${TRACE+--verbose} --coverage --junit --output=reports/rust-test.xunit.xml $RUST_BUILD_ARGS
    - output_coverage
  # TODO: code coverage support and GitLab integration (see: https://docs.gitlab.com/ee/ci/yaml/#coverage)
  coverage: '/^(\d+.\d+\%) covered$/'
  # keep build artifacts and test reports (see: https://docs.gitlab.com/ee/ci/yaml/#artifactsreportsjunit)
  artifacts:
    name: "$CI_JOB_NAME artifacts from $CI_PROJECT_NAME on $CI_COMMIT_REF_SLUG"
    expire_in: 1 day
    reports:
      # TODO: Unit tests use JUnit format and GitLab integration (see: https://docs.gitlab.com/ee/ci/yaml/#artifactsreports)
      junit:
        - reports/rust-test.xunit.xml
    paths:
        - build/
        - reports/
  tags: $[[ inputs.rust-build-job-tags ]]

# (example) linter job
rust-lint:
  extends: .rust-base
  stage: build
  image: $RUST_LINT_IMAGE
  # force no dependency
  dependencies: []
  script:
    - mkdir -p -m 777 reports
    - cargo_lint ${TRACE+--verbose} --output=reports/rust-lint.native.json $RUST_LINT_ARGS
  artifacts:
    name: "$CI_JOB_NAME artifacts from $CI_PROJECT_NAME on $CI_COMMIT_REF_SLUG"
    expire_in: 1 day
    when: always
    paths:
      - reports/rust-lint.*
  rules:
    # exclude if $RUST_LINT_DISABLED
    - if: '$RUST_LINT_DISABLED == "true"'
      when: never
    # .test-policy rules
    - !reference [.test-policy, rules]
  tags: $[[ inputs.rust-lint-job-tags ]]

# (example) dependency check job
rust-depcheck:
  extends: .rust-base
  stage: test
  image: $RUST_DEPCHECK_IMAGE
  # force no dependency
  dependencies: []
  script:
    - cargo_depcheck ${TRACE+--verbose} $RUST_DEPCHECK_ARGS
  rules:
    # on schedule: auto
    - if: '$CI_PIPELINE_SOURCE == "schedule"'
      allow_failure: true
      when: always
    # all other cases: manual & non-blocking
    - when: manual
      allow_failure: true
  tags: $[[ inputs.rust-depcheck-job-tags ]]

# (example) publish job activated on env ($RUST_PUBLISH_ENABLED), with required $RUST_PUBLISH_LOGIN and $RUST_PUBLISH_PASSWORD env verification
rust-publish:
  extends: .rust-base
  stage: publish
  before_script:
    - !reference [.rust-scripts]
    # verify $RUST_PUBLISH_LOGIN and $RUST_PUBLISH_PASSWORD are set
    - assert_defined "$RUST_PUBLISH_LOGIN" 'Missing required env $RUST_PUBLISH_LOGIN'
    - assert_defined "$RUST_PUBLISH_PASSWORD" 'Missing required env $RUST_PUBLISH_PASSWORD'
    - cargo login --login=$RUST_PUBLISH_LOGIN --password=$RUST_PUBLISH_PASSWORD
  script:
    - cargo $RUST_PUBLISH_ARGS
  rules:
    # exclude if $RUST_PUBLISH_ENABLED unset
    - if: '$RUST_PUBLISH_ENABLED != "true"'
      when: never
    # on integration or production branch(es): manual & non-blocking
    - if: '$CI_COMMIT_REF_NAME =~ $INTEG_REF || $CI_COMMIT_REF_NAME =~ $PROD_REF'
      when: manual
      allow_failure: true
  tags: $[[ inputs.rust-publish-job-tags ]]
