/**
 * The assistant widget is a package-owned shared fragment. Its chrome ships
 * with soma-ai beside that fragment; Hosts only install this published asset.
 *
 * This is deliberately separate from the generated-page Tailwind sheet:
 * generated pages use a closed vocabulary, while the assistant owns a stable
 * interactive DOM contract and must remain usable when that sheet changes.
 */
export const SOMA_AI_ASSISTANT_WIDGET_STYLESHEET_ID = 'soma-ai-assistant-widget-stylesheet';

export const SOMA_AI_ASSISTANT_WIDGET_CSS = `
#ai-assistant-widget {
  position: fixed;
  right: 1rem;
  bottom: 1rem;
  /* Stay above the shared sticky navbar (z-index 80) while remaining below
     modal/toast layers owned by soma-ui. */
  z-index: 90;
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  gap: .75rem;
  color: var(--soma-text-primary, #1f2937);
  font-family: var(--soma-font-family, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif);
  /* Keep the widget on the active SOMA typography axis.  A fixed 14px body
     follows the shared SOMA typography axis without depending on generated page CSS. */
  font-size: var(--soma-font-size-md, 1rem);
  line-height: var(--soma-line-height, 1.5715);
  isolation: isolate;
}

#ai-assistant-widget,
#ai-assistant-widget * {
  box-sizing: border-box;
}

#ai-assistant-widget:not([data-mounted="true"]) {
  display: none;
}

#ai-assistant-widget [hidden] {
  display: none !important;
}

#ai-assistant-panel {
  position: relative;
  display: flex;
  flex-direction: column;
  width: min(420px, calc(100vw - 1.5rem));
  /* dvh: the panel is sized to fit what is visible right now, so it must
     follow the toolbar instead of the toolbar-collapsed viewport. */
  height: min(720px, calc(100dvh - 6.5rem));
  min-height: 0;
  overflow: hidden;
  border: 1px solid var(--soma-border, #e5e7eb);
  border-radius: 1rem;
  background: var(--soma-bg-container, #fff);
  color: var(--soma-text-primary, #1f2937);
  box-shadow: 0 12px 40px rgb(15 23 42 / 16%);
}

#ai-assistant-panel > header {
  display: flex;
  flex: 0 0 auto;
  align-items: center;
  justify-content: space-between;
  min-height: 3.25rem;
  padding: .75rem 1rem;
  border-bottom: 1px solid var(--soma-divider, #eef2f7);
}

#ai-assistant-panel > header > div:first-child,
#ai-assistant-panel > header > div:last-child {
  display: flex;
  align-items: center;
}

#ai-assistant-panel > header > div:first-child {
  min-width: 0;
  gap: .5rem;
}

#ai-assistant-panel > header > div:last-child {
  gap: .125rem;
}

#ai-assistant-panel button {
  /* The host may ship a button reset with a stronger selector.  Set only the
     family here; size/weight belong to each control below so a button's
     typography cannot silently win over the assistant's text scale. */
  font-family: inherit;
  cursor: pointer;
}

#ai-assistant-panel button:disabled {
  cursor: not-allowed;
  opacity: .5;
}

#ai-assistant-panel > header button,
#ai-assistant-history-close {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 2rem;
  height: 2rem;
  padding: 0;
  border: 0;
  border-radius: .5rem;
  background: transparent;
  color: #6b7280;
}

#ai-assistant-panel > header button:hover,
#ai-assistant-history-close:hover {
  background: #f3f4f6;
  color: #111827;
}

#ai-assistant-panel > header img {
  display: block;
  width: var(--soma-ui-icon-xl, 1.5rem);
  height: var(--soma-ui-icon-xl, 1.5rem);
  object-fit: contain;
}

#ai-assistant-panel > header > div:first-child > span:first-child {
  display: flex;
  flex: 0 0 auto;
  align-items: center;
  justify-content: center;
  width: 2rem;
  height: 2rem;
  overflow: hidden;
  border-radius: 999px;
  background: #eff6ff;
  box-shadow: 0 0 0 1px #bfdbfe;
}

#ai-assistant-title {
  min-width: 0;
  overflow: hidden;
  color: #111827;
  font-size: var(--soma-font-size-md, 1rem);
  font-weight: var(--soma-font-weight-bold, 600);
  line-height: var(--soma-line-height-tight, 1.25);
  text-overflow: ellipsis;
  white-space: nowrap;
}

#ai-assistant-history-panel {
  position: absolute;
  inset-inline: 0;
  top: 3.25rem;
  bottom: 0;
  z-index: 10;
  display: flex;
  flex-direction: column;
  border-top: 1px solid var(--soma-divider, #eef2f7);
  background: var(--soma-bg-container, #fff);
}

#ai-assistant-history-panel > div:first-child {
  display: flex;
  flex: 0 0 auto;
  align-items: center;
  justify-content: space-between;
  padding: .625rem 1rem;
  border-bottom: 1px solid var(--soma-divider, #eef2f7);
}

#ai-assistant-history-panel > div:first-child > span {
  color: #111827;
  font-size: var(--soma-font-size-sm, .875rem);
  font-weight: var(--soma-font-weight-medium, 500);
  line-height: var(--soma-line-height-tight, 1.25);
}

#ai-assistant-history-list {
  min-height: 0;
  flex: 1 1 auto;
  overflow-y: auto;
  padding: .75rem;
}

#ai-assistant-history-list > div {
  display: flex;
  align-items: center;
  gap: .25rem;
  padding: .375rem .5rem;
  border-radius: .75rem;
}

#ai-assistant-history-list > div:hover {
  background: #f9fafb;
}

#ai-assistant-history-list > div > button {
  border: 0;
  background: transparent;
  color: #9ca3af;
}

#ai-assistant-history-list > div > button:first-child {
  min-width: 0;
  flex: 1 1 auto;
  padding: .25rem;
  color: var(--soma-text-primary, #374151);
  font-size: var(--soma-font-size-sm, .875rem);
  line-height: var(--soma-line-height, 1.5715);
  text-align: left;
}

#ai-assistant-history-list > div > button:last-child {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 1.75rem;
  height: 1.75rem;
  padding: 0;
  border-radius: .375rem;
}

#ai-assistant-history-list > div > button:last-child:hover {
  background: #fee2e2;
  color: #dc2626;
}

#ai-assistant-messages {
  min-height: 0;
  display: flex;
  flex: 1 1 auto;
  flex-direction: column;
  gap: .625rem;
  overflow-y: auto;
  padding: .75rem 1rem;
  background: var(--soma-bg-container, #fff);
}

#ai-assistant-messages [data-role="welcome"] {
  display: flex;
  flex-direction: column;
  gap: .75rem;
  padding-top: .25rem;
}

#ai-assistant-messages [data-role="welcome"] p {
  margin: 0;
}

#ai-assistant-messages [data-role="welcome"] > div:first-child > p:first-child {
  color: #111827;
  font-size: var(--soma-font-size-lg, 1.125rem);
  font-weight: var(--soma-font-weight-bold, 600);
  line-height: var(--soma-line-height-tight, 1.25);
}

#ai-assistant-messages [data-role="welcome"] > div:first-child > p:nth-child(2),
#ai-assistant-messages [data-role="suggested-prompts"] > p {
  color: #6b7280;
  font-size: var(--soma-font-size-sm, .875rem);
  line-height: var(--soma-line-height, 1.5715);
}

#ai-assistant-messages [data-role="suggested-prompts"] {
  display: flex;
  flex-direction: column;
  gap: .5rem;
}

#ai-assistant-messages [data-role="quick-prompt"] {
  padding: .625rem .75rem;
  border: 1px solid #e5e7eb;
  border-radius: .75rem;
  background: #f9fafb;
  color: #374151;
  font-size: var(--soma-font-size-sm, .875rem);
  font-weight: var(--soma-font-weight-normal, 400);
  line-height: var(--soma-line-height, 1.5715);
  text-align: left;
  transition: border-color .15s ease, background-color .15s ease, color .15s ease;
}

#ai-assistant-messages [data-role="quick-prompt"]:hover {
  border-color: #bfdbfe;
  background: #eff6ff;
  color: #1d4ed8;
}

#ai-assistant-messages .ai-msg {
  flex: 0 0 auto;
  padding: .5rem .875rem;
  border-radius: 1rem;
  font-size: var(--soma-font-size-sm, .875rem);
  line-height: var(--soma-line-height, 1.5715);
  overflow-wrap: break-word;
}

#ai-assistant-messages .ai-msg[data-role="user"] {
  align-self: flex-end;
  max-width: calc(100% - 2.5rem);
  margin-left: 2.5rem;
  background: #2563eb;
  color: #fff;
  box-shadow: 0 1px 2px rgb(15 23 42 / 8%);
}

#ai-assistant-messages .ai-msg[data-role="assistant"] {
  align-self: flex-start;
  max-width: calc(100% - 1.5rem);
  margin-right: 1.5rem;
  border: 1px solid #eef2f7;
  background: #f8fafc;
  color: #1f2937;
}

#ai-assistant-messages .ai-msg-text p {
  margin: 0 0 .5rem;
}

#ai-assistant-messages .ai-msg-text p:last-child {
  margin-bottom: 0;
}

#ai-assistant-messages .ai-msg-text pre {
  max-width: 100%;
  margin: .5rem 0;
  overflow-x: auto;
  padding: .625rem .75rem;
  border-radius: .5rem;
  background: #111827;
  color: #f9fafb;
  font-size: .75rem;
  line-height: 1.25rem;
  white-space: pre-wrap;
}

#ai-assistant-messages .ai-msg-text code {
  padding: .125rem .25rem;
  border-radius: .25rem;
  background: rgb(15 23 42 / 8%);
  font-size: .875em;
}

#ai-assistant-messages .ai-msg-text pre code {
  padding: 0;
  background: transparent;
}

#ai-assistant-messages .ai-msg-text ul,
#ai-assistant-messages .ai-msg-text ol {
  margin: .5rem 0;
  padding-inline-start: 1.25rem;
}

#ai-assistant-messages .ai-msg-text a {
  color: #1d4ed8;
  text-decoration: underline;
}

#ai-assistant-messages .ai-msg-tools {
  margin-top: .375rem;
}

#ai-assistant-messages .ai-tool {
  border: 1px solid #e5e7eb;
  border-radius: .5rem;
  background: #f9fafb;
  color: #4b5563;
  font-size: var(--soma-font-size-xs, .75rem);
  line-height: var(--soma-line-height-tight, 1.25);
}

#ai-assistant-messages .ai-tool summary {
  padding: .25rem .5rem;
  cursor: pointer;
}

#ai-assistant-status {
  flex: 0 0 auto;
  padding: .5rem 1rem;
  border-top: 1px solid #fff7ed;
  background: #fff7ed;
  color: #9a3412;
  font-size: var(--soma-font-size-xs, .75rem);
  line-height: var(--soma-line-height, 1.5715);
}

#ai-assistant-form {
  flex: 0 0 auto;
  padding: .75rem;
  border-top: 1px solid var(--soma-divider, #eef2f7);
  background: var(--soma-bg-container, #fff);
}

#ai-assistant-form > div {
  padding: .5rem .75rem;
  border: 1px solid #e5e7eb;
  border-radius: 1rem;
  background: #fafafa;
}

#ai-assistant-form > div:focus-within {
  border-color: #93c5fd;
  background: #fff;
  box-shadow: 0 0 0 2px #dbeafe;
}

#ai-assistant-input {
  display: block;
  width: 100%;
  min-height: 2.5rem;
  max-height: 7rem;
  padding: 0;
  resize: none;
  border: 0;
  outline: 0;
  background: transparent;
  color: #111827;
  font-size: var(--soma-font-size-sm, .875rem);
  line-height: var(--soma-line-height, 1.5715);
}

#ai-assistant-input::placeholder {
  color: #9ca3af;
}

#ai-assistant-form > div > div {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: .5rem;
  margin-top: .25rem;
}

#ai-assistant-form > div > div > span {
  color: var(--soma-text-secondary, #4b5563);
  font-size: var(--soma-font-size-xs, .75rem);
  line-height: var(--soma-line-height-tight, 1.25);
}

#ai-assistant-form > div > div > div {
  display: flex;
  align-items: center;
  gap: .5rem;
}

#ai-assistant-panel #ai-assistant-send,
#ai-assistant-panel #ai-assistant-stop {
  height: var(--soma-ui-control-h-sm, 2rem);
  min-height: var(--soma-ui-control-h-sm, 2rem);
  padding: 0 var(--soma-ui-control-pad-sm, .625rem);
  border-radius: 999px;
  font-size: var(--soma-ui-control-font-sm, .75rem);
  font-weight: var(--soma-font-weight-medium, 500);
  line-height: var(--soma-line-height-tight, 1.25);
}

#ai-assistant-send {
  display: inline-flex;
  align-items: center;
  gap: .25rem;
  border: 0;
  background: #2563eb;
  color: #fff;
}

#ai-assistant-send:hover {
  background: #1d4ed8;
}

#ai-assistant-stop {
  border: 1px solid #fecaca;
  background: #fff;
  color: #dc2626;
}

#ai-assistant-stop:hover {
  background: #fef2f2;
}

#ai-assistant-send svg {
  width: var(--soma-ui-icon-sm, .875rem);
  height: var(--soma-ui-icon-sm, .875rem);
}

#ai-assistant-fab {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  width: 3.5rem;
  height: 3.5rem;
  padding: 0;
  overflow: hidden;
  border: 0;
  border-radius: 999px;
  background: #fff;
  box-shadow: 0 8px 24px rgb(37 99 235 / 28%);
  cursor: pointer;
  outline: 0;
  transition: filter .15s ease, transform .15s ease, box-shadow .15s ease;
}

#ai-assistant-fab:hover {
  filter: brightness(1.05);
}

#ai-assistant-fab:active {
  transform: scale(.9);
  box-shadow: 0 4px 12px rgb(37 99 235 / 22%);
}

#ai-assistant-fab:focus-visible {
  box-shadow: 0 0 0 2px #fff, 0 0 0 4px #93c5fd, 0 8px 24px rgb(37 99 235 / 28%);
}

#ai-assistant-fab > span:first-child {
  display: flex;
  align-items: center;
  justify-content: center;
}

#ai-assistant-fab img {
  display: block;
  width: 2.75rem;
  height: 2.75rem;
  object-fit: contain;
}

#ai-assistant-badge:not([hidden]) {
  position: absolute;
  top: -.125rem;
  right: -.125rem;
  display: block;
  width: .75rem;
  height: .75rem;
  border: 2px solid #fff;
  border-radius: 999px;
  background: #ef4444;
}

#ai-assistant-widget .sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

@media (max-width: 640px) {
  #ai-assistant-widget {
    right: .75rem;
    bottom: .75rem;
  }

  #ai-assistant-panel {
    position: fixed;
    inset-inline: .5rem;
    top: 3.5rem;
    bottom: 4.5rem;
    width: auto;
    height: auto;
    border-radius: 1rem;
  }

  #ai-assistant-fab {
    width: 3rem;
    height: 3rem;
  }

  #ai-assistant-fab img {
    width: 2.25rem;
    height: 2.25rem;
  }
}
`;

export function ensureSomaAiAssistantWidgetStylesheet(
  doc: Document = document,
): HTMLStyleElement {
  const existing = doc.getElementById(SOMA_AI_ASSISTANT_WIDGET_STYLESHEET_ID);
  if (existing && existing.tagName !== 'STYLE') {
    existing.remove();
  }

  const style = existing?.tagName === 'STYLE'
    ? existing as HTMLStyleElement
    : doc.createElement('style');
  style.id = SOMA_AI_ASSISTANT_WIDGET_STYLESHEET_ID;
  style.dataset.somaAiAssistantWidget = 'package';
  style.removeAttribute('media');
  const nonce = doc.querySelector('meta[name="csp-nonce"]')?.getAttribute('content')?.trim();
  if (nonce && style.nonce !== nonce) {
    style.setAttribute('nonce', nonce);
    style.nonce = nonce;
  }
  if (style.textContent !== SOMA_AI_ASSISTANT_WIDGET_CSS) {
    style.textContent = SOMA_AI_ASSISTANT_WIDGET_CSS;
  }

  if (!style.isConnected) doc.head.appendChild(style);
  return style;
}