#!/usr/bin/env bash
## detect-memory-lsphp.sh — sibling of detect-memory-litespeed.sh for the
## cac-lsphp DETACHED sidecar (lsphp -b, no local webserver).
##
## Computes PHP_LSAPI_CHILDREN from the container memory cap. Identical worker
## arithmetic to detect-memory-litespeed.sh, with ONE difference: there is no
## OpenLiteSpeed daemon in this container (OLS runs in the shared-ols tier), so
## the ~40 MB OLS_RESERVE is dropped — every MB above the OS reserve goes to
## lsphp workers. Sourced by entrypoint-lsphp.sh.

## ---- container memory detection (mirrors detect-memory-litespeed.sh) ----
CONTAINER_MEMORY_BYTES=""

if [ -f /sys/fs/cgroup/memory.max ]; then
  val=$(cat /sys/fs/cgroup/memory.max 2>/dev/null)
  if [ "$val" != "max" ] && [ -n "$val" ]; then
    CONTAINER_MEMORY_BYTES=$val
  fi
fi

if [ -z "$CONTAINER_MEMORY_BYTES" ] && [ -f /sys/fs/cgroup/memory/memory.limit_in_bytes ]; then
  val=$(cat /sys/fs/cgroup/memory/memory.limit_in_bytes 2>/dev/null)
  if [ -n "$val" ] && [ "$val" -lt 8589934592000 ] 2>/dev/null; then
    CONTAINER_MEMORY_BYTES=$val
  fi
fi

if [ -z "$CONTAINER_MEMORY_BYTES" ] && [ -f /proc/meminfo ]; then
  mem_kb=$(awk '/^MemTotal:/ {print $2}' /proc/meminfo)
  if [ -n "$mem_kb" ]; then
    CONTAINER_MEMORY_BYTES=$((mem_kb * 1024))
  fi
fi

if [ -z "$CONTAINER_MEMORY_BYTES" ]; then
  CONTAINER_MEMORY_BYTES=$((512 * 1024 * 1024))
fi

CONTAINER_MEMORY_MB=$((CONTAINER_MEMORY_BYTES / 1024 / 1024))

## ---- budget split (all non-OS memory is the lsphp workers' to use) ----
OS_RESERVE_MB=50
DEV_OVERHEAD_MB=0
if [ "${environment:-PROD}" = "DEV" ]; then
  DEV_OVERHEAD_MB=125
fi

AVAILABLE_MB=$((CONTAINER_MEMORY_MB - OS_RESERVE_MB - DEV_OVERHEAD_MB))
if [ "$AVAILABLE_MB" -lt 60 ]; then
  AVAILABLE_MB=60
fi

## ---- LSAPI children ----
## Same ~130 MB/worker estimate as cac-litespeed (see detect-memory-litespeed.sh
## for the vantagehealth/brain-jar OOM history that set this). Detached lsphp
## has the SAME per-worker shmem-RSS profile as in-container lsphp — splitting
## the webserver out doesn't change lsphp's memory model, only removes the OLS
## daemon footprint from the budget.
LSPHP_WORKER_ESTIMATE_MB=${LSPHP_WORKER_ESTIMATE_MB:-130}

calc_lsapi_children=$((AVAILABLE_MB / LSPHP_WORKER_ESTIMATE_MB))
if [ "$calc_lsapi_children" -lt 2 ]; then
  calc_lsapi_children=2
fi
if [ "$calc_lsapi_children" -gt 50 ]; then
  calc_lsapi_children=50
fi

## Per-site override precedence — the WHP panel (site-pool-env.php) passes the
## customer's override as LSAPI_CHILDREN and/or FPM_MAX_CHILDREN; either wins
## over the calculated default. entrypoint-lsphp.sh exports the result as
## PHP_LSAPI_CHILDREN (the name lsphp -b reads).
LSAPI_CHILDREN=${LSAPI_CHILDREN:-${FPM_MAX_CHILDREN:-$calc_lsapi_children}}

export CONTAINER_MEMORY_MB LSAPI_CHILDREN