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

SCRIPT_DIR="$(cd -- "$(dirname -- "${BASH_SOURCE[0]}")" && pwd)"
PROJECT_DIR="$(cd -- "$SCRIPT_DIR/.." && pwd)"

TARGET_CWD="${TARGET_CWD:-$PROJECT_DIR}"
CONFIG_FILE="${SUBAGENTS_CONFIG:-$PROJECT_DIR/subagents.conf}"

AGENTS=(ui pipeline rules tests)
declare -A AGENT_SCOPES=(
  [ui]="templates/ static/ frontend/ src/ui/ src/components/ src/app/"
  [pipeline]="pipeline/ runtime/ schemas/ guards/ src/pipeline/ src/runtime/"
  [rules]="rules/ rule-packs/ policies/ validation/ src/rules/"
  [tests]="tests/ test/ spec/ fixtures/ harness/ e2e/"
)
declare -A AGENT_RESPONSIBILITIES=(
  [ui]="Implement and review user-facing UI, templates, static assets, and component behavior."
  [pipeline]="Implement and review pipeline flow, runtime behavior, schemas, and guard logic."
  [rules]="Implement and review rule packs, policy definitions, validation behavior, and rule docs."
  [tests]="Add and maintain focused test coverage, fixtures, harnesses, and test documentation."
)

ACPX_CMD=()

usage() {
  cat <<'USAGE'
Usage:
  acpx-subagents [--cwd DIR] [--config FILE] doctor
  acpx-subagents [--cwd DIR] [--config FILE] ensure [agent...]
  acpx-subagents [--cwd DIR] [--config FILE] send [--no-wait] [--file FILE] <agent> [prompt...]
  acpx-subagents [--cwd DIR] [--config FILE] parallel [--no-wait|--wait] [agent...] -- [prompt...]
  acpx-subagents [--cwd DIR] [--config FILE] sessions
  acpx-subagents [--cwd DIR] [--config FILE] show <agent>
  acpx-subagents [--cwd DIR] [--config FILE] history <agent> [limit]
  acpx-subagents [--cwd DIR] [--config FILE] close [agent...]

Environment:
  ACPX_BIN          Override acpx command, e.g. "acpx" or "npx -y acpx@0.1.15"
  SUBAGENTS_CONFIG  Override config file path
  TARGET_CWD        Default target repository/workspace
USAGE
}

fail() {
  printf 'error: %s\n' "$*" >&2
  exit 1
}

absolute_dir() {
  local dir="$1"
  [[ -d "$dir" ]] || fail "directory does not exist: $dir"
  (cd -- "$dir" && pwd)
}

load_config() {
  [[ -f "$CONFIG_FILE" ]] || return 0
  # shellcheck source=/dev/null
  source "$CONFIG_FILE"
}

agent_exists() {
  local candidate="$1"
  local agent
  for agent in "${AGENTS[@]}"; do
    [[ "$agent" == "$candidate" ]] && return 0
  done
  return 1
}

agents_or_all() {
  if (($# == 0)); then
    printf '%s\n' "${AGENTS[@]}"
    return 0
  fi

  local agent
  for agent in "$@"; do
    agent_exists "$agent" || fail "unknown agent '$agent' (known: ${AGENTS[*]})"
    printf '%s\n' "$agent"
  done
}

resolve_acpx() {
  if ((${#ACPX_CMD[@]} > 0)); then
    return 0
  fi

  if [[ -n "${ACPX_BIN:-}" ]]; then
    read -r -a ACPX_CMD <<< "$ACPX_BIN"
  elif command -v acpx >/dev/null 2>&1; then
    ACPX_CMD=(acpx)
  else
    ACPX_CMD=(npx -y acpx@latest)
  fi
}

run_acpx() {
  resolve_acpx
  "${ACPX_CMD[@]}" --cwd "$TARGET_CWD" codex "$@"
}

compose_prompt() {
  local agent="$1"
  local task="$2"
  local scope="${AGENT_SCOPES[$agent]:-not configured}"
  local responsibility="${AGENT_RESPONSIBILITIES[$agent]:-Work only on the assigned task.}"

  cat <<PROMPT
You are the "$agent" Codex subagent for this repository.

Responsibility:
$responsibility

File ownership:
$scope

Collaboration rules:
- You are not alone in this codebase; other agents may be editing their owned paths.
- Do not revert or overwrite changes made by others.
- Keep edits inside your ownership unless this task explicitly grants a wider scope.
- If the task needs files outside your ownership, stop and report the exact paths and reason.
- Finish with a concise summary of changed files, tests run, and remaining risks.

Task:
$task
PROMPT
}

cmd_doctor() {
  printf 'target cwd: %s\n' "$TARGET_CWD"
  printf 'config:     %s\n' "$CONFIG_FILE"

  if git -C "$TARGET_CWD" rev-parse --show-toplevel >/dev/null 2>&1; then
    printf 'git root:   %s\n' "$(git -C "$TARGET_CWD" rev-parse --show-toplevel)"
  else
    printf 'git root:   none; acpx will scope sessions to the exact target cwd\n'
  fi

  local cmd
  for cmd in node npm npx codex; do
    if command -v "$cmd" >/dev/null 2>&1; then
      printf 'ok:         %-5s %s\n' "$cmd" "$(command -v "$cmd")"
    else
      printf 'missing:    %s\n' "$cmd"
    fi
  done

  if [[ -n "${ACPX_BIN:-}" ]]; then
    printf 'acpx:       ACPX_BIN=%s\n' "$ACPX_BIN"
  elif command -v acpx >/dev/null 2>&1; then
    printf 'acpx:       %s\n' "$(command -v acpx)"
  else
    printf 'acpx:       not installed; will use npx -y acpx@latest\n'
  fi

  printf 'agents:     %s\n' "${AGENTS[*]}"
}

cmd_ensure() {
  local agent
  while IFS= read -r agent; do
    printf 'ensuring session: %s\n' "$agent" >&2
    run_acpx sessions ensure --name "$agent"
  done < <(agents_or_all "$@")
}

cmd_send() {
  local no_wait=0
  local prompt_file=""

  while (($# > 0)); do
    case "$1" in
      --no-wait)
        no_wait=1
        shift
        ;;
      --file)
        (($# >= 2)) || fail "--file requires a path"
        prompt_file="$2"
        shift 2
        ;;
      --)
        shift
        break
        ;;
      -*)
        fail "unknown send option: $1"
        ;;
      *)
        break
        ;;
    esac
  done

  (($# >= 1)) || fail "send requires an agent"
  local agent="$1"
  shift
  agent_exists "$agent" || fail "unknown agent '$agent' (known: ${AGENTS[*]})"

  while (($# > 0)); do
    case "$1" in
      --no-wait)
        no_wait=1
        shift
        ;;
      --file)
        (($# >= 2)) || fail "--file requires a path"
        prompt_file="$2"
        shift 2
        ;;
      --)
        shift
        break
        ;;
      -*)
        fail "unknown send option: $1"
        ;;
      *)
        break
        ;;
    esac
  done

  local task=""
  if [[ -n "$prompt_file" ]]; then
    [[ -f "$prompt_file" ]] || fail "prompt file does not exist: $prompt_file"
    task="$(< "$prompt_file")"
    if (($# > 0)); then
      task+=$'\n\n'
      task+="$*"
    fi
  else
    task="$*"
  fi

  [[ -n "${task//[[:space:]]/}" ]] || fail "send requires prompt text or --file"

  local prompt
  prompt="$(compose_prompt "$agent" "$task")"

  local args=(-s "$agent")
  if ((no_wait == 1)); then
    args+=(--no-wait)
  fi

  run_acpx "${args[@]}" "$prompt"
}

cmd_parallel() {
  local no_wait=1
  local selected=()

  while (($# > 0)); do
    case "$1" in
      --no-wait)
        no_wait=1
        shift
        ;;
      --wait)
        no_wait=0
        shift
        ;;
      --)
        shift
        break
        ;;
      *)
        if agent_exists "$1"; then
          selected+=("$1")
          shift
        else
          break
        fi
        ;;
    esac
  done

  if ((${#selected[@]} == 0)); then
    selected=("${AGENTS[@]}")
  fi

  local task="$*"
  [[ -n "${task//[[:space:]]/}" ]] || fail "parallel requires prompt text after --"

  local agent
  for agent in "${selected[@]}"; do
    if ((no_wait == 1)); then
      cmd_send --no-wait "$agent" "$task"
    else
      cmd_send "$agent" "$task"
    fi
  done
}

cmd_sessions() {
  run_acpx sessions list
}

cmd_show() {
  (($# == 1)) || fail "show requires exactly one agent"
  agent_exists "$1" || fail "unknown agent '$1' (known: ${AGENTS[*]})"
  run_acpx sessions show "$1"
}

cmd_history() {
  (($# >= 1 && $# <= 2)) || fail "history requires an agent and optional limit"
  local agent="$1"
  local limit="${2:-20}"
  agent_exists "$agent" || fail "unknown agent '$agent' (known: ${AGENTS[*]})"
  run_acpx sessions history "$agent" --limit "$limit"
}

cmd_close() {
  local agent
  while IFS= read -r agent; do
    printf 'closing session: %s\n' "$agent" >&2
    run_acpx sessions close "$agent"
  done < <(agents_or_all "$@")
}

TARGET_CWD="$(absolute_dir "$TARGET_CWD")"

COMMAND=""
while (($# > 0)); do
  case "$1" in
    --cwd)
      (($# >= 2)) || fail "--cwd requires a directory"
      TARGET_CWD="$(absolute_dir "$2")"
      shift 2
      ;;
    --config)
      (($# >= 2)) || fail "--config requires a file"
      CONFIG_FILE="$2"
      shift 2
      ;;
    -h|--help|help)
      usage
      exit 0
      ;;
    doctor|ensure|send|parallel|sessions|show|history|close)
      COMMAND="$1"
      shift
      break
      ;;
    *)
      fail "unknown command or option: $1"
      ;;
  esac
done

load_config

case "$COMMAND" in
  doctor) cmd_doctor "$@" ;;
  ensure) cmd_ensure "$@" ;;
  send) cmd_send "$@" ;;
  parallel) cmd_parallel "$@" ;;
  sessions) cmd_sessions "$@" ;;
  show) cmd_show "$@" ;;
  history) cmd_history "$@" ;;
  close) cmd_close "$@" ;;
  "")
    usage
    ;;
  *)
    fail "unknown command: $COMMAND"
    ;;
esac