#!/usr/bin/env bash
# conved – file conversion via conved.com from the command line (Linux, macOS; needs only bash and curl).
# Documentation: https://www.conved.com/docs
#
#   conved login                      store the API token (account at https://www.conved.com/account)
#   conved convert <file|URL> -t <format> [-o <output>]
#   conved formats [<format>]         conved status <id>   conved get <id> [-o <output>]   conved me
#
# Token: env CONVED_TOKEN, otherwise the file ${XDG_CONFIG_HOME:-~/.config}/conved/token (CONVED_TOKEN_FILE).
# stdout gets only the path of the result (for scripts), messages go to stderr. Exit codes:
#   0 done, 1 usage, 2 conversion failed / unsupported, 3 limit reached, 4 bad token, 5 network / server, 6 timeout
set -u -o pipefail

VERSION="1.0.8"
API="${CONVED_API:-https://www.conved.com/api/v1}"
TOKEN_FILE="${CONVED_TOKEN_FILE:-${XDG_CONFIG_HOME:-$HOME/.config}/conved/token}"
QUIET=0

say()  { [ "$QUIET" = 1 ] || printf '%s\n' "$*" >&2; }
die()  { printf 'conved: %s\n' "$2" >&2; exit "$1"; }

usage() {
	cat >&2 <<HELP
conved $VERSION – file conversion via conved.com

Usage:
  conved login                               store API token (asks for it, or reads it from stdin)
  conved logout                              remove stored token
  conved convert <file|url> -t <format> [-o <output>] [--no-wait] [--timeout <s>] [-q]
                                             convert and download the result (prints its path)
  conved status <id> [--wait <s>]            job status
  conved get <id> [-o <output>]              download result of a finished job
  conved formats [<format>]                  supported conversions (all, or targets for <format>)
  conved me                                  account and limits
  conved version | help

Examples:
  conved convert slides.ppt -t pdf
  conved convert report.docx -t pdf -o /var/www/report.pdf
  conved convert 'https://www.youtube.com/watch?v=3RmQTYLD398' -t mp3

Token: env CONVED_TOKEN, or file $TOKEN_FILE
Exit codes: 0 done, 1 usage, 2 conversion failed/unsupported, 3 limit reached, 4 bad token, 5 network/server, 6 timeout
HELP
}

command -v curl >/dev/null 2>&1 || die 5 "curl is required"

token() {
	if [ -n "${CONVED_TOKEN:-}" ]; then printf '%s' "$CONVED_TOKEN"; return; fi
	[ -r "$TOKEN_FILE" ] || die 4 "no API token – run 'conved login' (create a token at https://www.conved.com/account)"
	tr -d ' \r\n' < "$TOKEN_FILE"
}

# value from a flat JSON API response (string or number); no jq/python needed
json() {
	local v
	v=$(printf '%s' "$1" | sed -nE 's/.*"'"$2"'":"((\\.|[^"\\])*)".*/\1/p' | head -n1)
	[ -z "$v" ] && v=$(printf '%s' "$1" | sed -nE 's/.*"'"$2"'":(-?[0-9]+|true|false|null).*/\1/p' | head -n1)
	printf '%s' "$v" | sed -e 's#\\/#/#g' -e 's/\\"/"/g' -e 's/\\\\/\\/g'
}

# API call: api METHOD PATH [curl arguments…] → sets BODY and CODE
api() {
	local method=$1 path=$2 out
	shift 2
	# token goes to curl on stdin (printf is a shell builtin) – never on the command line, where `ps` would show it
	out=$(printf 'Authorization: Bearer %s\n' "$(token)" | curl -sS --proto =https,http --connect-timeout 15 -X "$method" -H @- \
		-H "Accept: application/json" -H "User-Agent: conved-cli/$VERSION" -w $'\n%{http_code}' "$@" "$API$path") || die 5 "cannot reach $API"
	CODE=${out##*$'\n'}
	BODY=${out%$'\n'*}
}

# API error → message and exit code by error type
api_fail() {
	local err msg
	err=$(json "$BODY" error); msg=$(json "$BODY" message)
	case "$err" in
		unauthorized) die 4 "${msg:-invalid token}" ;;
		limit_reached) die 3 "${msg:-limit reached}" ;;
		unsupported_format|unsupported_target|file_too_large|download_failed) die 2 "${msg:-$err}" ;;
		bad_request|method_not_allowed|not_found|upload_failed) die 1 "${msg:-$err}" ;;
		*)
			# not an API JSON response → rejected by the web server / firewall before reaching the application
			[ -z "$err" ] && [ "$CODE" = 403 -o "$CODE" = 500 -o "$CODE" = 413 ] && die 5 "rejected by the server firewall (HTTP $CODE) – contact info@conved.com"
			die 5 "server error (HTTP $CODE)${msg:+: $msg}" ;;
	esac
}

download() {   # download <id> <output>
	local url out=$2
	api GET "/jobs/$1"
	[ "$CODE" = 200 ] || api_fail
	url=$(json "$BODY" download_url)
	[ -n "$url" ] || die 2 "job $1 is not finished (status: $(json "$BODY" status))"
	if [ -z "$out" ]; then   # name from the server: no directories, no leading dot or dash
		out=$(json "$BODY" name); out=${out##*/}; out=${out#[.-]}
	fi
	out=${out:-conved-$1}
	curl -fsS --proto =https --connect-timeout 15 -o "$out.part" "$url" || { rm -f "$out.part"; die 5 "download failed"; }
	mv -f "$out.part" "$out"
	say "saved $out"
	printf '%s\n' "$out"
}

cmd_login() {
	local t=${1:-}
	if [ -z "$t" ] && [ -t 0 ]; then
		printf 'API token (https://www.conved.com/account): ' >&2
		read -rs t; echo >&2
	elif [ -z "$t" ] || [ "$t" = - ]; then   # from stdin (scripts): echo "$TOKEN" | conved login
		read -r t
	else
		say "note: a token on the command line is visible to other users (ps) – prefer 'conved login' or stdin"
	fi
	t=$(printf '%s' "$t" | tr -d ' \r\n')
	case "$t" in cvd_*) ;; *) die 1 "a token starts with cvd_" ;; esac
	CONVED_TOKEN=$t api GET /me
	[ "$CODE" = 200 ] || api_fail
	mkdir -p "$(dirname "$TOKEN_FILE")"
	( umask 077; printf '%s\n' "$t" > "$TOKEN_FILE" )
	say "signed in as $(json "$BODY" email), token saved to $TOKEN_FILE"
}

cmd_convert() {
	local src="" to="" out="" wait=1 timeout=900 id status started
	while [ $# -gt 0 ]; do
		case "$1" in
			-t|--to) to=${2:-}; shift ;;
			-o|--output) out=${2:-}; shift ;;
			--no-wait) wait=0 ;;
			--timeout) timeout=${2:-900}; shift ;;
			-q|--quiet) QUIET=1 ;;
			-*) die 1 "unknown option $1" ;;
			*) [ -z "$src" ] && src=$1 || die 1 "only one input file" ;;
		esac
		shift
	done
	[ -n "$src" ] && [ -n "$to" ] || { usage; exit 1; }
	to=$(printf '%s' "$to" | tr '[:upper:]' '[:lower:]')

	case "$src" in
		http://*|https://*) say "converting $src → $to"; api POST /convert --form-string "url=$src" --form-string "to=$to" -F "wait=40" ;;
		*)
			[ -f "$src" ] && [ -r "$src" ] || die 1 "file not found: $src"
			say "uploading $src → $to"
			api POST /convert -F "file=@\"$src\"" --form-string "to=$to" -F wait=40
			[ -n "$out" ] || out="$(dirname "$src")/$(basename "${src%.*}").$to"
			;;
	esac
	[ "$CODE" = 200 ] || [ "$CODE" = 202 ] || api_fail
	id=$(json "$BODY" id); status=$(json "$BODY" status)
	[ -n "$id" ] || die 5 "unexpected server response"
	if [ "$wait" = 0 ]; then printf '%s\n' "$id"; return; fi

	started=$(date +%s)
	while [ "$status" = waiting ]; do
		[ $(( $(date +%s) - started )) -lt "$timeout" ] || die 6 "timeout – the job $id is still running (conved status $id)"
		say "converting… (job $id)"
		api GET "/jobs/$id?wait=30"
		[ "$CODE" = 200 ] || api_fail
		status=$(json "$BODY" status)
	done
	[ "$status" = done ] || die 2 "conversion failed: $(json "$BODY" error)"
	download "$id" "$out"
}

cmd_status() {
	local id=${1:-} w=0
	[ -n "$id" ] || die 1 "usage: conved status <id> [--wait <s>]"
	[ "${2:-}" = "--wait" ] && w=${3:-30}
	api GET "/jobs/$id?wait=$w"
	[ "$CODE" = 200 ] || api_fail
	printf '%s\n' "$(json "$BODY" status)"
}

cmd_formats() {
	local list
	if [ -n "${1:-}" ]; then
		api GET "/formats?from=$1"
		[ "$CODE" = 200 ] || api_fail
		list=$(printf '%s' "$BODY" | sed -nE 's/.*:\[([^]]*)\].*/\1/p' | tr -d '"' | tr ',' ' ')
		[ -n "$list" ] || die 2 "format '$1' is not supported"
		printf '%s\n' "$list"
	else
		api GET /formats
		[ "$CODE" = 200 ] || api_fail
		printf '%s' "$BODY" | sed -E 's/^\{"formats":\{//; s/\}\}$//; s/\],"/]\n"/g' | sed -E 's/"([^"]+)":\[(.*)\]/\1: \2/; s/"//g; s/,/ /g'
		echo
	fi
}

case "${1:-help}" in
	login) shift; cmd_login "$@" ;;
	logout) rm -f "$TOKEN_FILE"; say "token removed" ;;
	convert|c) shift; cmd_convert "$@" ;;
	status) shift; cmd_status "$@" ;;
	get) shift; id=${1:-}; [ -n "$id" ] || die 1 "usage: conved get <id> [-o <output>]"; [ "${2:-}" = "-o" ] && o=${3:-} || o=""; download "$id" "$o" ;;
	formats) shift; cmd_formats "$@" ;;
	me) api GET /me; [ "$CODE" = 200 ] || api_fail; printf '%s\n' "$BODY" ;;
	version|-v|--version) echo "conved $VERSION" ;;
	help|-h|--help) usage ;;
	*) usage; exit 1 ;;
esac