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

BINARY_NAME="email-mcp"
DEFAULT_PROFILE="default"
PROFILE_ENV="EMAIL_MCP_PROFILE"
RELEASE_BASE_URL="https://gitea.lclr.dev"
RELEASE_REPOSITORY="AI/email-mcp"

prompt() {
	local label="$1"
	local default_value="$2"
	local answer=""

	if [ -n "$default_value" ]; then
		printf "%s [%s]: " "$label" "$default_value"
	else
		printf "%s: " "$label"
	fi

	if [ -r /dev/tty ]; then
		IFS= read -r answer < /dev/tty || answer=""
	else
		IFS= read -r answer || answer=""
	fi

	if [ -z "$answer" ]; then
		printf "%s" "$default_value"
		return
	fi

	printf "%s" "$answer"
}

detect_os() {
	case "$(uname -s | tr '[:upper:]' '[:lower:]')" in
		linux) printf "linux" ;;
		darwin) printf "darwin" ;;
		*)
			printf "OS non supporté: %s\n" "$(uname -s)" >&2
			exit 1
			;;
	esac
}

detect_arch() {
	case "$(uname -m)" in
		x86_64|amd64) printf "amd64" ;;
		aarch64|arm64) printf "arm64" ;;
		*)
			printf "Architecture non supportée: %s\n" "$(uname -m)" >&2
			exit 1
			;;
	esac
}

release_api_url() {
	printf "%s/api/v1/repos/%s/releases/latest\n" "${RELEASE_BASE_URL%/}" "$RELEASE_REPOSITORY"
}

extract_asset_url() {
	local json="$1"
	local asset_name="$2"

	printf "%s\n" "$json" \
		| grep -o '"browser_download_url":"[^"]*"' \
		| sed 's/"browser_download_url":"//;s/"$//' \
		| sed 's#\\/#/#g' \
		| grep "/${asset_name}$" \
		| head -n 1
}

go_bin_dir() {
	local gobin
	gobin="$(go env GOBIN 2>/dev/null || true)"
	if [ -n "$gobin" ]; then
		printf "%s\n" "$gobin"
		return
	fi

	go env GOPATH 2>/dev/null | awk '{print $1 "/bin"}'
}

resolve_binary_path() {
	if command -v "$BINARY_NAME" >/dev/null 2>&1; then
		command -v "$BINARY_NAME"
		return
	fi

	if command -v go >/dev/null 2>&1; then
		local bin_dir
		bin_dir="$(go_bin_dir)"
		if [ -n "$bin_dir" ] && [ -x "$bin_dir/$BINARY_NAME" ]; then
			printf "%s\n" "$bin_dir/$BINARY_NAME"
			return
		fi
	fi

	printf "%s\n" "$HOME/.local/bin/$BINARY_NAME"
}

verify_checksum() {
	local binary_path="$1"
	local checksum_path="$2"

	if command -v sha256sum >/dev/null 2>&1; then
		( cd "$(dirname "$binary_path")" && sha256sum -c "$(basename "$checksum_path")" )
		return
	fi

	if command -v shasum >/dev/null 2>&1; then
		local expected
		local actual
		expected="$(awk '{print $1}' "$checksum_path")"
		actual="$(shasum -a 256 "$binary_path" | awk '{print $1}')"
		if [ "$expected" != "$actual" ]; then
			printf "Checksum invalide pour %s\n" "$binary_path" >&2
			exit 1
		fi
		return
	fi

	printf "Aucun utilitaire de checksum trouvé (sha256sum/shasum), vérification ignorée.\n" >&2
}

download_latest_release_binary() {
	if ! command -v curl >/dev/null 2>&1; then
		printf "curl est requis pour télécharger la release.\n" >&2
		exit 1
	fi

	local os_name
	local arch_name
	local ext=""
	os_name="$(detect_os)"
	arch_name="$(detect_arch)"
	if [ "$os_name" = "windows" ]; then
		ext=".exe"
	fi

	local asset_name
	local checksum_name
	asset_name="${BINARY_NAME}-${os_name}-${arch_name}${ext}"
	checksum_name="${asset_name}.sha256"

	printf "Récupération de la dernière release...\n"
	local release_json
	release_json="$(curl -fsSL "$(release_api_url)")"

	local asset_url
	asset_url="$(extract_asset_url "$release_json" "$asset_name")"
	if [ -z "$asset_url" ]; then
		printf "Asset introuvable dans la dernière release: %s\n" "$asset_name" >&2
		exit 1
	fi

	local checksum_url
	checksum_url="$(extract_asset_url "$release_json" "$checksum_name" || true)"

	local tmp_dir
	tmp_dir="$(mktemp -d)"
	trap 'rm -rf "$tmp_dir"' EXIT INT TERM

	curl -fsSL "$asset_url" -o "$tmp_dir/$asset_name"
	chmod +x "$tmp_dir/$asset_name"

	if [ -n "$checksum_url" ]; then
		curl -fsSL "$checksum_url" -o "$tmp_dir/$checksum_name"
		verify_checksum "$tmp_dir/$asset_name" "$tmp_dir/$checksum_name"
	fi

	local target_dir
	target_dir="$(prompt "Répertoire d'installation" "$HOME/.local/bin")"
	mkdir -p "$target_dir"
	install -m 0755 "$tmp_dir/$asset_name" "$target_dir/$BINARY_NAME"

	printf "Binaire installé: %s/%s\n" "$target_dir" "$BINARY_NAME"
	printf "Ajoute ce dossier au PATH si nécessaire.\n"
}

install_binary() {
	if command -v "$BINARY_NAME" >/dev/null 2>&1; then
		printf "Binaire détecté: %s\n" "$(command -v "$BINARY_NAME")"
		local reinstall
		reinstall="$(prompt "Forcer une réinstallation depuis la dernière release ? (y/N)" "N")"
		case "$reinstall" in
			y|Y|yes|YES)
				download_latest_release_binary
				;;
			*)
				return
				;;
		esac
		return
	fi

	download_latest_release_binary
}

run_setup_wizard() {
	install_binary

	local profile
	profile="$(prompt "Profil à configurer (${PROFILE_ENV})" "$DEFAULT_PROFILE")"
	local binary_path
	binary_path="$(resolve_binary_path)"

	printf "Lancement de %s setup...\n\n" "$BINARY_NAME"
	if [ -r /dev/tty ] && [ -w /dev/tty ]; then
		env "${PROFILE_ENV}=${profile}" "$binary_path" setup < /dev/tty > /dev/tty
	else
		env "${PROFILE_ENV}=${profile}" "$binary_path" setup
	fi
}

print_mcp_json() {
	local profile
	profile="$(prompt "Profil à exposer dans la config MCP (${PROFILE_ENV})" "$DEFAULT_PROFILE")"
	local default_command
	default_command="$(resolve_binary_path)"
	local command_path
	command_path="$(prompt "Commande du serveur MCP" "$default_command")"

	cat <<JSON
{
  "mcpServers": {
    "${BINARY_NAME}": {
      "command": "${command_path}",
      "args": ["mcp"],
      "env": {
        "${PROFILE_ENV}": "${profile}"
      }
    }
  }
}
JSON
}

print_header() {
	cat <<TXT
===========================================================
Installateur MCP pour ${BINARY_NAME}
===========================================================
Choisis une action :
  1) Installer le binaire + lancer le setup
  2) Générer un JSON de config MCP (Codex)
  3) Générer un JSON de config MCP (Claude Desktop)
  4) Générer un JSON de config MCP (autre client)
  5) Quitter
TXT
}

main() {
	while true; do
		print_header
		local choice
		choice="$(prompt "Choix" "1")"
		printf "\n"

		case "$choice" in
			1)
				run_setup_wizard
				printf "\nInstallation terminée.\n"
				return
				;;
			2|3|4)
				printf "Copie ce JSON dans la config MCP du client ciblé.\n\n"
				print_mcp_json
				return
				;;
			5)
				printf "Annulé.\n"
				return
				;;
			*)
				printf "Choix invalide: %s\n\n" "$choice" >&2
				;;
		esac
	done
}

main "$@"