#!/usr/bin/env bash
# Headless-Chrome smoke test for frontend.html.
#
# Two kinds of checks:
#   • STATIC  — markup that's in the file regardless of rendering (buttons,
#     controls). Grepped straight from frontend.html → 100% reliable.
#   • DYNAMIC — proof the page actually rendered: CodeMirror mounted (its CDN/ESM
#     imports ran), the editor wrap was revealed and the textarea fallback hidden.
#     These need a real browser, so we render with headless Chrome.
#
# Only the dynamic half can flake (CDN timing), so the headless dump is retried
# until it's complete. Static checks never touch the browser.
#
# Usage: ./smoke-test.sh   (exit 0 = pass, 1 = fail)
set -euo pipefail
cd "$(dirname "$0")"

FILE="frontend.html"
src="$(cat "$FILE")"

CHROME="${CHROME:-/Applications/Google Chrome.app/Contents/MacOS/Google Chrome}"
[ -x "$CHROME" ] || { echo "✗ Chrome not found at: $CHROME (set \$CHROME)"; exit 1; }

# Retry the dump until it's a COMPLETE render (has </html> AND the CodeMirror
# mount), up to 5 attempts — guards against partial/pre-render dumps.
dom=""
for attempt in 1 2 3 4 5; do
    dom="$("$CHROME" --headless --disable-gpu --no-sandbox \
            --virtual-time-budget=25000 \
            --dump-dom "file://$PWD/$FILE" 2>/dev/null)"
    if grep -q '</html>' <<<"$dom" && grep -q 'class="cm-editor' <<<"$dom"; then
        break
    fi
    [ "$attempt" -lt 5 ] && { echo "… incomplete render (attempt $attempt), retrying"; sleep 1; }
done

fail=0
chk() { # chk "<haystack>" "<label>" "<grep -E pattern>" "<want: yes|no>"
    # here-string (not echo|grep): with `set -o pipefail`, grep -q matching closes
    # the pipe early → echo gets SIGPIPE → the pipeline falsely reports failure.
    if grep -qE "$3" <<<"$1"; then found=yes; else found=no; fi
    if [ "$found" = "$4" ]; then echo "✓ $2"; else echo "✗ $2 (wanted match=$4, got=$found)"; fail=1; fi
}
static() { chk "$src" "$1" "$2" "$3"; }   # grep the source file
dynamic(){ chk "$dom" "$1" "$2" "$3"; }   # grep the rendered DOM

echo "— dynamic (needs a real render) —"
dynamic "editor mounted (.cm-editor present)"      'class="cm-editor'                            yes
dynamic "line-number gutter rendered"              'class="cm-gutterElement'                     yes
dynamic "editor-wrap revealed by JS (not hidden)"  '<div id="editor-wrap" class="editor-wrap">' yes
dynamic "textarea fallback hidden by JS"           '<textarea id="code-fallback"[^>]*hidden'    yes

echo "— static (markup in the file) —"
static "language selector present"                 'id="lang-select"'                            yes
static "Copy / Clear buttons present"              'id="copy-btn".*|id="clear-btn"'              yes
static "Generate is compact (in action bar)"       '<button id="submit-btn" class="btn-primary"' yes
static "output toolbar present (Copy Mermaid)"     'id="copy-mmd-btn"'                            yes
static "SVG / PNG export buttons present"          'id="svg-btn".*|id="png-btn"'                 yes
static "export buttons disabled until a render"    '<button id="svg-btn"[^>]*disabled'           yes
static "theme toggle present"                      'id="theme-toggle"'                           yes
static "zoom controls present"                     'id="zoom-ctrl"'                              yes
static "flow-arrow cue present"                    'class="flow-arrow"'                          yes

echo
[ "$fail" -eq 0 ] && echo "PASS" || echo "FAIL"
exit "$fail"