copilot-powerline 0.3.2

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

readonly FEATURES_URL="https://github.com/settings/copilot/features"
readonly SESSION_PREFIX="copilot-powerline-github-usage-"

# Prints a token identifying a process by its start time, or nothing if the
# process is gone. Paired with the PID, it survives PID reuse.
run_token() {
    local started
    started="$(ps -o lstart= -p "$1" 2>/dev/null)" || return 0
    printf '%s' "$started" | cksum | cut -d' ' -f1
}

readonly SESSION_NAME="${SESSION_PREFIX}$$-$(run_token $$)"

profile="${COPILOT_USAGE_BROWSER_PROFILE:-${HOME}/.copilot/github-usage-profile}"
cache_file="${COPILOT_USAGE_CACHE_FILE:-${HOME}/.copilot/github-usage.json}"
history_file="${COPILOT_USAGE_HISTORY_FILE:-${HOME}/.copilot/github-usage-history.jsonl}"
html_file=""
login=false
write_cache=true
write_history=true

usage() {
    cat <<'EOF'
Usage: fetch-github-copilot-usage [--login] [--html-file FILE] [--no-cache] [--no-history]

Fetch the signed-in user's GitHub Copilot usage counter and print JSON.

  --login             Open a persistent browser profile for one-time GitHub login.
  --html-file FILE    Parse a saved page text fixture instead of opening a browser.
  --no-cache          Do not write the result to ~/.copilot/github-usage.json.
  --no-history        Do not append the result to ~/.copilot/github-usage-history.jsonl.

Environment:
  COPILOT_USAGE_BROWSER_PROFILE  Persistent browser profile location.
  COPILOT_USAGE_CACHE_FILE       Output cache location.
  COPILOT_USAGE_HISTORY_FILE     Append-only run history location (JSON Lines).
EOF
}

while (($#)); do
    case "$1" in
        --login)
            login=true
            ;;
        --html-file)
            shift
            html_file="${1:-}"
            [[ -n "$html_file" ]] || {
                echo "--html-file requires a path" >&2
                exit 2
            }
            ;;
        --no-cache)
            write_cache=false
            ;;
        --no-history)
            write_history=false
            ;;
        -h|--help)
            usage
            exit 0
            ;;
        *)
            echo "Unknown option: $1" >&2
            usage >&2
            exit 2
            ;;
    esac
    shift
done

# Session names end with the PID and start-time token of the run that opened
# them. A session whose run has exited was leaked and may still hold the
# browser profile lock.
close_stale_browser_sessions() {
    local session pid token
    for session in $(agent-browser session list 2>/dev/null |
        grep -Eo "${SESSION_PREFIX}[0-9]+-[0-9]+" || true); do
        token="${session##*-}"
        pid="${session#"$SESSION_PREFIX"}"
        pid="${pid%-*}"
        [[ "$(run_token "$pid")" == "$token" ]] && continue
        agent-browser --session "$session" close >/dev/null 2>&1 || true
    done
}

if "$login"; then
    command -v agent-browser >/dev/null || {
        echo "agent-browser is required. Install it before running --login." >&2
        exit 1
    }

    close_stale_browser_sessions
    # A successful login session stays open for the user; only a failed open is closed.
    agent-browser --session "$SESSION_NAME" --profile "$profile" --headed open "$FEATURES_URL" || {
        status=$?
        agent-browser --session "$SESSION_NAME" close >/dev/null 2>&1 || true
        exit "$status"
    }
    cat <<'EOF'
Sign in to GitHub in the browser window, including SSO or two-factor authentication if required.
Close the window when finished, then run this command again without --login.
EOF
    exit 0
fi

if [[ -n "$html_file" ]]; then
    [[ -r "$html_file" ]] || {
        echo "Cannot read page text: $html_file" >&2
        exit 1
    }
    page_text="$(<"$html_file")"
else
    command -v agent-browser >/dev/null || {
        echo "agent-browser is required. Run this script with --login after installing it." >&2
        exit 1
    }

    close_stale_browser_sessions
    cleanup_browser_session() {
        agent-browser --session "$SESSION_NAME" close >/dev/null 2>&1 || true
    }
    trap cleanup_browser_session EXIT
    agent-browser --session "$SESSION_NAME" --profile "$profile" open "$FEATURES_URL" >/dev/null
    page_text="$(agent-browser --session "$SESSION_NAME" read)"
    agent-browser --session "$SESSION_NAME" close >/dev/null
    trap - EXIT
fi

if [[ "$page_text" == *"Sign in to GitHub"* ]]; then
    echo "GitHub login is required. Run: $0 --login" >&2
    exit 1
fi

if ! credits="$(printf '%s\n' "$page_text" |
    grep -Em1 -o '[0-9][0-9,]* AI credits used' |
    tr -cd '0-9')"; then
    credits=""
fi

if ! cycle="$(printf '%s\n' "$page_text" |
    grep -Em1 -o '[A-Z][a-z]+ [0-9]{1,2}-[0-9]{1,2}, [0-9]{4}')"; then
    cycle=""
fi

[[ -n "$credits" && -n "$cycle" ]] || {
    echo "Could not find Copilot usage on the features page. GitHub may have changed the page." >&2
    exit 1
}

usd="$(awk -v credits="$credits" 'BEGIN { printf "%.2f", credits / 100 }')"
result="$(printf '{"ai_credits_used":%s,"usd":"%s","cycle":"%s"}' "$credits" "$usd" "$cycle")"

if "$write_cache"; then
    umask 077
    mkdir -p "$(dirname "$cache_file")"
    temporary_cache="$(mktemp "${cache_file}.tmp.XXXXXX")"
    printf '%s\n' "$result" >"$temporary_cache"
    mv "$temporary_cache" "$cache_file"
fi

if "$write_history"; then
    umask 077
    mkdir -p "$(dirname "$history_file")"
    timestamp="$(date -u +%Y-%m-%dT%H:%M:%SZ)"
    printf '{"ts":"%s","ai_credits_used":%s,"usd":"%s","cycle":"%s"}\n' \
        "$timestamp" "$credits" "$usd" "$cycle" >>"$history_file"
fi

printf '%s\n' "$result"