#!/usr/bin/env bash
set -euo pipefail

# Reusable HTTP and graph client helpers for local unix-socket amduatd usage.

graph_helpers_init() {
  if [[ $# -lt 1 ]]; then
    echo "usage: graph_helpers_init ROOT_DIR" >&2
    return 1
  fi
  GRAPH_HELPERS_ROOT_DIR="$1"
  GRAPH_HELPERS_HTTP="${GRAPH_HELPERS_ROOT_DIR}/build/amduatd_http_unix"
  GRAPH_HELPERS_USE_HTTP=0

  if command -v curl >/dev/null 2>&1; then
    if curl --help 2>/dev/null | grep -q -- '--unix-socket'; then
      GRAPH_HELPERS_USE_HTTP=0
    else
      GRAPH_HELPERS_USE_HTTP=1
    fi
  else
    GRAPH_HELPERS_USE_HTTP=1
  fi

  if [[ "${GRAPH_HELPERS_USE_HTTP}" -eq 1 && ! -x "${GRAPH_HELPERS_HTTP}" ]]; then
    echo "missing http transport (need curl --unix-socket or build/amduatd_http_unix)" >&2
    return 1
  fi
}

graph_http_get() {
  local sock="$1"
  local path="$2"
  shift 2
  if [[ "${GRAPH_HELPERS_USE_HTTP}" -eq 1 ]]; then
    "${GRAPH_HELPERS_HTTP}" --sock "${sock}" --method GET --path "${path}" "$@"
  else
    curl --silent --show-error --fail \
      --unix-socket "${sock}" \
      "$@" \
      "http://localhost${path}"
  fi
}

graph_http_get_allow() {
  local sock="$1"
  local path="$2"
  shift 2
  if [[ "${GRAPH_HELPERS_USE_HTTP}" -eq 1 ]]; then
    "${GRAPH_HELPERS_HTTP}" --sock "${sock}" --method GET --path "${path}" --allow-status "$@"
  else
    curl --silent --show-error \
      --unix-socket "${sock}" \
      "$@" \
      "http://localhost${path}"
  fi
}

graph_http_post() {
  local sock="$1"
  local path="$2"
  local data="$3"
  shift 3
  if [[ "${GRAPH_HELPERS_USE_HTTP}" -eq 1 ]]; then
    "${GRAPH_HELPERS_HTTP}" --sock "${sock}" --method POST --path "${path}" --data "${data}" "$@"
  else
    curl --silent --show-error --fail \
      --unix-socket "${sock}" \
      "$@" \
      --data-binary "${data}" \
      "http://localhost${path}"
  fi
}

graph_http_post_allow() {
  local sock="$1"
  local path="$2"
  local data="$3"
  shift 3
  if [[ "${GRAPH_HELPERS_USE_HTTP}" -eq 1 ]]; then
    "${GRAPH_HELPERS_HTTP}" --sock "${sock}" --method POST --path "${path}" --data "${data}" --allow-status "$@"
  else
    curl --silent --show-error \
      --unix-socket "${sock}" \
      "$@" \
      --data-binary "${data}" \
      "http://localhost${path}"
  fi
}

graph_wait_for_ready() {
  local sock="$1"
  local pid="$2"
  local log_path="$3"
  local i
  for i in $(seq 1 120); do
    if ! kill -0 "${pid}" >/dev/null 2>&1; then
      if [[ -f "${log_path}" ]] && grep -q "bind: Operation not permitted" "${log_path}"; then
        echo "skip: bind not permitted for unix socket" >&2
        return 77
      fi
      if [[ -f "${log_path}" ]]; then
        cat "${log_path}" >&2
      fi
      return 1
    fi
    if [[ -S "${sock}" ]] && graph_http_get "${sock}" "/v1/meta" >/dev/null 2>&1; then
      return 0
    fi
    sleep 0.1
  done
  return 1
}

graph_batch_ingest() {
  local sock="$1"
  local space="$2"
  local payload="$3"
  graph_http_post "${sock}" "/v2/graph/batch" "${payload}" \
    --header "Content-Type: application/json" \
    --header "X-Amduat-Space: ${space}"
}

graph_changes_sync_once() {
  local sock="$1"
  local space="$2"
  local cursor="$3"
  local limit="$4"
  local path="/v2/graph/changes?limit=${limit}"
  if [[ -n "${cursor}" ]]; then
    path+="&since_cursor=${cursor}"
  fi
  graph_http_get "${sock}" "${path}" --header "X-Amduat-Space: ${space}"
}

graph_subgraph_fetch() {
  local sock="$1"
  local space="$2"
  local root="$3"
  local max_depth="$4"
  local predicates="${5:-}"
  local path="/v2/graph/subgraph?roots[]=${root}&max_depth=${max_depth}&dir=outgoing&limit_nodes=256&limit_edges=256"
  if [[ -n "${predicates}" ]]; then
    path+="&predicates[]=${predicates}"
  fi
  graph_http_get "${sock}" "${path}" --header "X-Amduat-Space: ${space}"
}

if [[ "${BASH_SOURCE[0]}" == "${0}" ]]; then
  if [[ $# -lt 1 ]]; then
    echo "usage: $0 COMMAND ..." >&2
    echo "commands: batch-ingest, sync-once, subgraph" >&2
    exit 2
  fi
  cmd="$1"
  shift
  : "${AMDUATD_ROOT:?set AMDUATD_ROOT to repo root}"
  graph_helpers_init "${AMDUATD_ROOT}"
  case "${cmd}" in
    batch-ingest)
      if [[ $# -ne 3 ]]; then
        echo "usage: $0 batch-ingest SOCK SPACE PAYLOAD_JSON" >&2
        exit 2
      fi
      graph_batch_ingest "$1" "$2" "$3"
      ;;
    sync-once)
      if [[ $# -ne 4 ]]; then
        echo "usage: $0 sync-once SOCK SPACE CURSOR LIMIT" >&2
        exit 2
      fi
      graph_changes_sync_once "$1" "$2" "$3" "$4"
      ;;
    subgraph)
      if [[ $# -lt 4 || $# -gt 5 ]]; then
        echo "usage: $0 subgraph SOCK SPACE ROOT MAX_DEPTH [PREDICATE]" >&2
        exit 2
      fi
      graph_subgraph_fetch "$1" "$2" "$3" "$4" "${5:-}"
      ;;
    *)
      echo "unknown command: ${cmd}" >&2
      exit 2
      ;;
  esac
fi