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

TOKEN=""
REPO_FULL=""
WORKFLOW_FILE=""
TARGET_REF=""
HEAD_SHA=""
SOURCE_WORKFLOW=""
BASE_NEEDED=""
BASE_HASH=""
TRACE_ID=""
MAX_ROUNDS=3

declare -a API_BASES=()
declare -a EXTRA_INPUTS=()

usage() {
  cat <<'EOF'
Usage:
  dispatch-workflow.sh \
    --token <token> \
    --repo <owner/repo> \
    --workflow <workflow-file> \
    --ref <branch-or-ref> \
    --head-sha <sha> \
    --source-workflow <name> \
    [--api-base <base-url>]... \
    [--base-needed <true|false>] \
    [--base-hash <hash>] \
    [--trace-id <id>] \
    [--input <key=value>]... \
    [--max-rounds <n>]
EOF
}

ensure_curl() {
  if command -v curl >/dev/null 2>&1; then
    return 0
  fi

  if command -v apt-get >/dev/null 2>&1; then
    export DEBIAN_FRONTEND=noninteractive
    apt-get update -qq
    apt-get install -y -qq curl ca-certificates
  fi

  if command -v curl >/dev/null 2>&1; then
    return 0
  fi

  echo "curl is required for dispatch and could not be installed" >&2
  return 1
}

build_default_api_bases() {
  if [[ -n "${GITHUB_SERVER_URL:-}" ]]; then
    API_BASES+=("${GITHUB_SERVER_URL%/}/api/v1")
  fi
  if [[ -n "${GITEA_SERVER_URL:-}" ]]; then
    API_BASES+=("${GITEA_SERVER_URL%/}/api/v1")
  fi
  if [[ -n "${GITEA_SSH_HOST:-}" ]]; then
    API_BASES+=("http://${GITEA_SSH_HOST}:3001/api/v1")
  fi
  if [[ -n "${GITEA_REGISTRY_HOST:-}" ]]; then
    API_BASES+=("http://${GITEA_REGISTRY_HOST}:3001/api/v1")
  fi
  if [[ -n "${GITEA_REGISTRY_IP:-}" ]]; then
    API_BASES+=("http://${GITEA_REGISTRY_IP}:3001/api/v1")
  fi
  if [[ ${#API_BASES[@]} -eq 0 ]]; then
    API_BASES+=("http://kankali.darkhelm.lan:3001/api/v1")
  fi
}

append_input_field() {
  local key="$1"
  local value="$2"
  [[ -z "$value" ]] && return 0
  PAYLOAD_INPUTS+=$',\n'
  PAYLOAD_INPUTS+="    \"${key}\": \"${value}\""
}

while [[ $# -gt 0 ]]; do
  case "$1" in
    --api-base)
      API_BASES+=("$2")
      shift 2
      ;;
    --token)
      TOKEN="$2"
      shift 2
      ;;
    --repo)
      REPO_FULL="$2"
      shift 2
      ;;
    --workflow)
      WORKFLOW_FILE="$2"
      shift 2
      ;;
    --ref)
      TARGET_REF="$2"
      shift 2
      ;;
    --head-sha)
      HEAD_SHA="$2"
      shift 2
      ;;
    --source-workflow)
      SOURCE_WORKFLOW="$2"
      shift 2
      ;;
    --base-needed)
      BASE_NEEDED="$2"
      shift 2
      ;;
    --base-hash)
      BASE_HASH="$2"
      shift 2
      ;;
    --trace-id)
      TRACE_ID="$2"
      shift 2
      ;;
    --input)
      EXTRA_INPUTS+=("$2")
      shift 2
      ;;
    --max-rounds)
      MAX_ROUNDS="$2"
      shift 2
      ;;
    --help|-h)
      usage
      exit 0
      ;;
    *)
      echo "Unknown argument: $1" >&2
      usage
      exit 2
      ;;
  esac
done

if [[ -z "$TOKEN" || -z "$REPO_FULL" || -z "$WORKFLOW_FILE" || -z "$TARGET_REF" || -z "$HEAD_SHA" || -z "$SOURCE_WORKFLOW" ]]; then
  echo "Missing required arguments" >&2
  usage
  exit 2
fi

if ! [[ "$MAX_ROUNDS" =~ ^[0-9]+$ ]] || [[ "$MAX_ROUNDS" -lt 1 ]]; then
  echo "--max-rounds must be a positive integer" >&2
  exit 2
fi

REPO_OWNER="${REPO_FULL%/*}"
REPO_NAME="${REPO_FULL#*/}"

if [[ ${#API_BASES[@]} -eq 0 ]]; then
  build_default_api_bases
fi

if [[ -z "$TRACE_ID" ]]; then
  TRACE_ID="dispatch-${GITHUB_RUN_ID:-local}-${GITHUB_RUN_ATTEMPT:-1}-${HEAD_SHA:0:8}"
fi

PAYLOAD_INPUTS=$'    "head_sha": "'"${HEAD_SHA}"$'",\n    "source_workflow": "'"${SOURCE_WORKFLOW}"$'"'
append_input_field "trace_id" "$TRACE_ID"
append_input_field "base_needed" "$BASE_NEEDED"
append_input_field "base_hash" "$BASE_HASH"

for kv in "${EXTRA_INPUTS[@]}"; do
  if [[ "$kv" != *=* ]]; then
    echo "Invalid --input value: ${kv} (expected key=value)" >&2
    exit 2
  fi
  key="${kv%%=*}"
  value="${kv#*=}"
  append_input_field "$key" "$value"
done

PAYLOAD=$(cat <<EOF
{
  "ref": "${TARGET_REF}",
  "inputs": {
${PAYLOAD_INPUTS}
  }
}
EOF
)

ensure_curl

echo "Dispatching ${WORKFLOW_FILE} for ${HEAD_SHA} on ${TARGET_REF}"
echo "trace_id=${TRACE_ID}"

dispatched=false
attempt=0
total_attempts=$((MAX_ROUNDS * ${#API_BASES[@]}))

for round in $(seq 1 "${MAX_ROUNDS}"); do
  for api_base in "${API_BASES[@]}"; do
    attempt=$((attempt + 1))
    dispatch_url="${api_base}/repos/${REPO_OWNER}/${REPO_NAME}/actions/workflows/${WORKFLOW_FILE}/dispatches"
    response_file="/tmp/dispatch-response.txt"
    : > "${response_file}"

    echo "dispatch_attempt=${attempt}/${total_attempts}"
    echo "dispatch_round=${round}/${MAX_ROUNDS}"
    echo "dispatch_api_base=${api_base}"

    dispatch_start_ms=$(date +%s%3N)
    http_code=$(curl -sS --connect-timeout 5 --max-time 20 -o "${response_file}" -w "%{http_code}" -X POST \
      -H "Authorization: token ${TOKEN}" \
      -H "Content-Type: application/json" \
      "${dispatch_url}" \
      -d "${PAYLOAD}" || true)
    dispatch_end_ms=$(date +%s%3N)
    dispatch_elapsed_ms=$((dispatch_end_ms - dispatch_start_ms))

    echo "dispatch_elapsed_ms=${dispatch_elapsed_ms}"
    echo "dispatch_http_code=${http_code}"

    if [[ "${http_code}" =~ ^[0-9]+$ ]] && [[ "${http_code}" -ge 200 ]] && [[ "${http_code}" -lt 300 ]]; then
      echo "Dispatch succeeded"
      dispatched=true
      break 2
    fi

    echo "Dispatch attempt failed via ${api_base} (HTTP ${http_code})"
    if [[ -s "${response_file}" ]]; then
      echo "Response body:"
      cat "${response_file}" || true
    fi
  done

  sleep_seconds=$((2 ** round))
  echo "Dispatch round ${round} failed; backing off for ${sleep_seconds}s"
  sleep "${sleep_seconds}"
done

if [[ "${dispatched}" != "true" ]]; then
  echo "Dispatch failed on all endpoints after ${MAX_ROUNDS} rounds" >&2
  exit 1
fi