#!/usr/bin/env bash

# file      : brep/handler/ci/ci-load.in
# copyright : Copyright (c) 2014-2019 Code Synthesis Ltd
# license   : MIT; see accompanying LICENSE file

# Package CI request handler that loads the packages into the brep database.
#
# --result-url <url>
#  Result URL base for the response. If specified, the handler will append the
#  brep tenant id to this value and include the resulting URL in the response
#  message.
#
# <loader-path>
#  Loader program (normally brep-load(1)).
#
# <loader-options>
#  Loader options (normally --db-*).
#
usage="usage: $0 [--result-url <url>] <loader-path> [<loader-options>] <dir>"

verbose= #true

# Repository information fetch timeout (seconds).
#
fetch_timeout=60

trap "{ exit 1; }" ERR
set -o errtrace # Trap ERR in functions.

@import brep/handler/handler@
@import brep/handler/ci/ci@

# The handler's own options.
#
result_url=
while [ $# -gt 0 ]; do
  case $1 in
    --result-url)
      shift
      result_url="${1%/}"
      shift
      ;;
    *)
      break
      ;;
  esac
done

# The loader path.
#
loader="$1"

if [ -z "$loader" ]; then
  error "$usage"
fi

shift

# Assume that the remaining arguments except the last one are the loader
# options.
#
loader_options=()
while [ $# -gt 1 ]; do
  loader_options+=("$1")
  shift
done

# CI request data directory (last argument).
#
data_dir="${1%/}"

if [ -z "$data_dir" ]; then
  error "$usage"
fi

if [ ! -d "$data_dir" ]; then
  error "'$data_dir' does not exist or is not a directory"
fi

reference="$(basename "$data_dir")"

# Parse the CI request manifest and obtain the repository URL, package names
# with optional versions, as well as the simulate value.
#
manifest_parser_start "$data_dir/request.manifest"

simulate=
repository=

# Package map. We first enter packages from the request manifest as keys and
# setting the values to true. Then we go through the repository package list
# consulting this map and, if found, clearing the value to empty. Finally, we
# go through the map looking for any "unhandled" packages (value is still
# true).
#
# Note that keys can be in both <name> and <name>/<version> forms.
#
declare -A packages

# While at it, produce the bpkg-build(1)-like package spec for tracing.
#
# The spec normally contains the full commit id and so feels too hairy to
# include in the result manifest message.
#
spec=

while IFS=: read -ru "$manifest_parser_ofd" -d '' n v; do
  case "$n" in
    simulate)   simulate="$v"   ;;
    repository) repository="$v" ;;

    package)
      packages["$v"]=true

      if [ -n "$spec" ]; then
        spec="$spec,"
      fi
      spec="$spec$v"
      ;;
  esac
done

manifest_parser_finish

if [ -n "$spec" ]; then
  spec="$spec@"
fi

spec="$spec$repository"

if [ -z "$repository" ]; then
  error "repository manifest value expected"
fi

if [ -n "$simulate" -a "$simulate" != "success" ]; then
  exit_with_manifest 400 "unrecognized simulation outcome '$simulate'"
fi

message_suffix=
if [ -n "$result_url" ]; then
  message_suffix=": $result_url/@$reference" # Append the tenant id.
fi

# Exit with the 'CI request is queued' response if simulating.
#
# Note that we can't assume a real repository URL is specified if simulating
# so trying to query the repository info is not a good idea.
#
if [ -n "$simulate" ]; then
  run rm -r "$data_dir"

  trace "CI request for '$spec' is simulated$message_suffix"
  exit_with_manifest 200 "CI request is queued$message_suffix"
fi

# Dump the repositories.manifest and packages.manifest files.
#
cache_dir="$data_dir/cache"
run mkdir "$cache_dir"
dump_repository_manifests "$repository" "$cache_dir" "$fetch_timeout"

# Filter the packages manifest keeping only the packages listed in the request
# manifest. Keep all the packages if the request specified no packages.
#

# Resulting manifest.
#
packages_manifest_names=()
packages_manifest_values=()

# While at it, set the repository display name to the first package's project
# name.
#
display_name=

manifest_parser_start "$cache_dir/packages.manifest"

# The outer loop iterates over package manifests while the inner loop iterates
# over manifest values in each such manifest.
#
# Note that the first manifest case is special in that we will see its version
# value (empty name) first while for others -- last, as part of the previous
# manifest. We try to deal with this irregularity by reducing the first case
# (manifest_version is empty) to "as-if" it followed another manifest.
#
manifest_names=()
manifest_values=()
manifest_version=

more=true
while [ "$more" ]; do

  if [ -n "$manifest_version" ]; then
    manifest_names=("")
    manifest_values=("$manifest_version")
  fi

  more=
  project=

  while IFS=: read -ru "$manifest_parser_ofd" -d '' n v; do
    case "$n" in
      "") # Start of (next) manifest.
        more=true
        manifest_version="$v"
        break
        ;;

      name)    name="$v"    ;;
      version) version="$v" ;;
      project) project="$v" ;;
    esac

    manifest_names+=("$n")
    manifest_values+=("$v")

  done

  # Reduce the first manifest case.
  #
  if [ ${#manifest_names[@]} -eq 0 ]; then
    continue
  fi

  # Add or filter out the manifest, if present.
  #
  if [ ${#packages[@]} -ne 0 ]; then

    if [[ -v packages["$name"] ]]; then
      packages["$name"]=
      packages["$name/$version"]= # Clear it either, as may also be present.
    elif [[ -v packages["$name/$version"] ]]; then
      packages["$name/$version"]=
    else
      continue # Skip.
    fi

  fi

  packages_manifest_names+=("${manifest_names[@]}")
  packages_manifest_values+=("${manifest_values[@]}")

  if [ -z "$display_name" ]; then
    if [ -n "$project" ]; then
      display_name="$project"
    else
      display_name="$name"
    fi
  fi
done

manifest_parser_finish

# Verify that all the listed in the request manifest packages are present in
# the repository.
#
for p in "${!packages[@]}"; do
  if [ "${packages[$p]}" ]; then
    exit_with_manifest 422 "unknown package $p"
  fi
done

# Verify that the repository is not empty. Failed that, the repository display
# name wouldn't be set.
#
if [ -z "$display_name" ]; then
  exit_with_manifest 422 "no packages in repository"
fi

# Stash the original packages manifest file for troubleshooting.
#
run mv "$cache_dir/packages.manifest" "$cache_dir/packages.manifest.orig"

# Serialize the filtered packages manifest.
#
manifest_serializer_start "$cache_dir/packages.manifest"

for ((i=0; i <= ${#packages_manifest_names[@]}; ++i)); do
  manifest_serialize "${packages_manifest_names[$i]}" \
                     "${packages_manifest_values[$i]}"
done

manifest_serializer_finish

# Create the brep-load(1) loadtab file.
#
loadtab="$data_dir/loadtab"
run echo "$repository $display_name cache:cache" >"$loadtab"

# Load the requested repository packages into the brep package database for
# the tenant identified by the reference.
#
run "$loader" "${loader_options[@]}" --force --shallow --tenant "$reference" \
"$loadtab"

# Remove the no longer needed CI request data directory.
#
run rm -r "$data_dir"

trace "CI request for '$spec' is queued$message_suffix"
exit_with_manifest 200 "CI request is queued$message_suffix"