#!/usr/bin/env bash
## plan-legs.sh - decide which image legs of build-push.yaml run.
##
## Env:
##   ONLY         workflow_dispatch input "only". Empty/blank (and every push
##                event) = build everything, exactly as before.
##   GITHUB_OUTPUT  file the outputs are appended to (set by the runner).
##
## ONLY is a comma list of tokens (spaces ignored):
##   cac:php85  cac-fpm:php84  cac-litespeed:php83  cac-lsphp:php82   one leg
##   cac | cac-fpm | cac-litespeed | cac-lsphp                         every PHP version of that image
##   shared-httpd | shared-ols                                         that image
## Any other token is an error (exit 2, nothing is written): a typo must fail
## the plan job loudly, never silently build nothing.
##
## Outputs (matrix families = JSON array of phpver, [] = skip the job;
## single-leg images = true|false):
##   cac cac_fpm cac_litespeed cac_lsphp shared_httpd shared_ols
set -euo pipefail

MATRIX_FAMILIES=(cac cac-fpm cac-litespeed cac-lsphp)
SINGLE_FAMILIES=(shared-httpd shared-ols)
ALL_PHPVER=(82 83 84 85)

die() { echo "plan-legs: $*" >&2; exit 2; }

only=${ONLY-}
only=${only//[[:space:]]/}

declare -A want_ver want_single
want_all=false

if [ -z "$only" ]; then
  want_all=true
else
  n=0
  IFS=',' read -r -a toks <<< "$only"
  for t in "${toks[@]}"; do
    [ -n "$t" ] || continue
    n=$((n + 1))
    fam=${t%%:*}
    ver=""
    if [ "$fam" != "$t" ]; then
      ver=${t#*:}
      [ -n "$ver" ] || die "empty PHP version in '$t'"
    fi
    if [[ " ${MATRIX_FAMILIES[*]} " == *" $fam "* ]]; then
      if [ -z "$ver" ]; then
        for v in "${ALL_PHPVER[@]}"; do want_ver["$fam:$v"]=1; done
      elif [[ "$ver" =~ ^php(8[2-5])$ ]]; then
        want_ver["$fam:${BASH_REMATCH[1]}"]=1
      else
        die "unknown PHP version in '$t' (want ${fam}:php82 .. ${fam}:php85)"
      fi
    elif [[ " ${SINGLE_FAMILIES[*]} " == *" $fam "* ]]; then
      [ "$fam" = "$t" ] || die "'$t': $fam has a single leg, use plain '$fam'"
      want_single["$fam"]=1
    else
      die "unknown image '$t' (known: ${MATRIX_FAMILIES[*]} ${SINGLE_FAMILIES[*]})"
    fi
  done
  [ "$n" -gt 0 ] || die "'only' has no usable entries: '$only'"
fi

matrix_json() {  # family
  local fam=$1 v out=""
  for v in "${ALL_PHPVER[@]}"; do
    if $want_all || [ -n "${want_ver["$fam:$v"]-}" ]; then out+="${out:+,}$v"; fi
  done
  printf '[%s]' "$out"
}
single_json() {  # family
  if $want_all || [ -n "${want_single["$1"]-}" ]; then echo true; else echo false; fi
}

out=${GITHUB_OUTPUT:-/dev/stdout}
{
  echo "cac=$(matrix_json cac)"
  echo "cac_fpm=$(matrix_json cac-fpm)"
  echo "cac_litespeed=$(matrix_json cac-litespeed)"
  echo "cac_lsphp=$(matrix_json cac-lsphp)"
  echo "shared_httpd=$(single_json shared-httpd)"
  echo "shared_ols=$(single_json shared-ols)"
} >> "$out"