lib

#!/usr/bin/env bash

# SPDX-FileCopyrightText: 2022 The Standard Authors
# SPDX-License-Identifier: Unlicense

# shellcheck disable=SC2016
: '
USAGE:

Example (.envrc):
  source $(fetchurl https://raw.githubusercontent.com/paisano-nix/direnv/main/lib <hash>)

Find hash:
   direnv fetchurl https://raw.githubusercontent.com/paisano-nix/direnv/main/lib
'

# signature direnv & nixago output styling
export DIRENV_LOG_FORMAT=$'\E[mdirenv: \E[38;5;8m%s\E[m'

{ # PRJ Base Directory Specification: https://github.com/numtide/prj-spec
	# shellcheck source=/dev/null
	source "$(
		fetchurl \
			"https://raw.githubusercontent.com/numtide/prj-spec/9b0ffcd0fddcb261bcd73ad9dad18a096760b4a0/contrib/direnv" \
			"sha256-54YaaGly6Q0E8GhFT9fB/h9tN1PDERo2/4R4X0Pdi/c="
	)"
}

{ # Paisano Block

	registry="git+file://$PRJ_ROOT#__std"
	nix=("nix")
	nix_eval_args=(
		"--no-update-lock-file"
		"--no-write-lock-file"
		"--no-warn-dirty"
		"--accept-flake-config"
	)
	nix_eval=("${nix[@]}" "eval" "${nix_eval_args[@]}")
	nix_build_args=(
		"--no-link"
		"--keep-outputs"
		"--build-poll-interval" "0"
		"--builders-use-substitutes"
	)
	nix_build=("${nix[@]}" "build" "${nix_eval_args[@]}" "${nix_build_args[@]}")

	system="$("${nix_eval[@]}" 2>/dev/null --raw --impure --expr builtins.currentSystem)"
	cellsFrom="$("${nix_eval[@]}" 2>/dev/null --raw "$registry.cellsFrom")"

	# Usage: use env <target>
	#
	# Loads the environment determined by the given target
	#
	#   use env //local/env/default
	use_env() {
		local input="$1"
		read -r cell block target <<<"${input//\// }"

		action="enter"

		local profile_path="${PRJ_DATA_HOME}/$cell/$block/$target"
		mkdir -p "${PRJ_DATA_HOME}/$cell/$block/$target"

		cmd=(
			"${nix_build[@]}"
			"--print-out-paths"
			"--profile"
			"$profile_path/enter-action"
			"$registry.actions.$system.$cell.$block.$target.$action"
		)

		if ! enter="$("${cmd[@]}")"; then
    			log_status "The follwing command just failed:"
    			log_status "${cmd[@]}"
    			read -rp "Rerun with --show-trace (y/N): " diagnose
			[[ "$diagnose" == "y" ]] && "${cmd[@]}" --show-trace
			exit 1
		fi

		export STD_DIRENV=1
		eval "$(<"$enter")"
		# this is not true
		unset IN_NIX_SHELL STD_DIRENV
	}

	_set_watchers() {
		local input="$1"
		read -r cell block target <<<"${input//\// }"
		local BLOCK_PATH="$cellsFrom/$cell/$block"
		local watchableFile=
		local watchableDir=

		if [[ -f "$BLOCK_PATH/$target.nix" ]]; then
			watchableFile="$BLOCK_PATH/$target.nix"
		elif [[ -f "$BLOCK_PATH/default.nix" ]]; then
			watchableFile="$BLOCK_PATH/default.nix"
		elif [[ -f "$BLOCK_PATH.nix" ]]; then
			watchableFile="$BLOCK_PATH.nix"
		fi

		if [[ -d "$BLOCK_PATH/$target" ]]; then
			watchableDir="$BLOCK_PATH/$target"
		fi

		if [[ -n $watchableFile ]]; then
			log_status "Watching: ${watchableFile}"
			watch_file "$watchableFile"
    		fi
		if [[ -n $watchableDir ]]; then
			log_status "Watching: ${watchableDir} (recursively)"
			watch_dir "$watchableDir"
    		fi

	}

	use_envreload() {
		for target in "${@}"; do
			_set_watchers "$target"
		done
		use_env "$1"
	}
}