#!/bin/bash
#
# Regenerates the swagger definitions served by this site.
#
# Usage: ./update_api_docs.sh [--latest-only] [sed -i suffix] [extra sed args...]
#
#   --latest-only   only refresh static/swagger-latest.json from gitea main,
#                   leaving the released static/swagger-<minor>.json untouched.

set -euo pipefail

LATEST_ONLY=0
if [ "${1:-}" = "--latest-only" ]; then
  LATEST_ONLY=1
  shift
fi

SED_INPLACE=(-i)
EXTRA_SED_ARGS=()

if [ "$#" -gt 0 ]; then
  SED_INPLACE=(-i "$1")
  shift
else
  if sed --version >/dev/null 2>&1; then
    SED_INPLACE=(-i)
  else
    SED_INPLACE=(-i '')
  fi
fi

EXTRA_SED_ARGS=("$@")

inplace_sed() {
  # ${arr[@]+...} keeps `set -u` happy with empty arrays on bash 3.2 (macOS)
  sed "${SED_INPLACE[@]}" ${EXTRA_SED_ARGS[@]+"${EXTRA_SED_ARGS[@]}"} "$@"
}

# gitea >= 1.28 ships a pre-generated json, older versions ship a go template
SWAGGER_PATHS=(
  'templates/swagger/v1-swagger.generated.json'
  'templates/swagger/v1_json.tmpl'
)

# download_swagger <git ref> <output file>
download_swagger() {
  local ref="$1" output="$2" path
  for path in "${SWAGGER_PATHS[@]}"; do
    if curl --silent --fail --location --output "$output" \
        "https://raw.githubusercontent.com/go-gitea/gitea/${ref}/${path}"; then
      return 0
    fi
  done
  echo "unable to download the swagger definition of ${ref}" >&2
  return 1
}

# rewrite_swagger <file> <version to display>
rewrite_swagger() {
  local file="$1" version="$2"
  # gitea >= 1.28
  inplace_sed "s|\"version\": \"0.0.0+GITEA-API-APP-VERSION\"|\"version\": \"${version}\"|" "$file"
  inplace_sed 's|"basePath": "/GITEA-API-APP-SUBURL/api/v1"|"basePath": "https://gitea.com/api/v1"|' "$file"
  # gitea >= 1.24
  inplace_sed "s|\"version\": \"{{.SwaggerAppVer}}\"|\"version\": \"${version}\"|" "$file"
  inplace_sed 's|"basePath": "{{.SwaggerAppSubUrl}}/api/v1"|"basePath": "https://gitea.com/api/v1"|' "$file"
  # gitea < 1.24
  inplace_sed "s|\"version\": \"{{AppVer \| JSEscape}}\"|\"version\": \"${version}\"|" "$file"
  inplace_sed "s#\"basePath\": \"{{AppSubUrl | JSEscape}}/api/v1\"#\"basePath\": \"https://gitea.com/api/v1\"#" "$file"
}

download_swagger 'refs/heads/main' v1_json.tmpl
rewrite_swagger v1_json.tmpl 'dev'
mv v1_json.tmpl static/swagger-latest.json

if [ "$LATEST_ONLY" -eq 1 ]; then
  exit 0
fi

for ver in '1.27.2' '1.26.4' '1.25.5' '1.24.7' '1.23.8' '1.22.6'; do
  download_swagger "refs/tags/v${ver}" v1_json.tmpl
  rewrite_swagger v1_json.tmpl "${ver}"
  minor=$(echo "$ver" | cut -d '.' -f 2)
  mv v1_json.tmpl "static/swagger-$minor.json"
done