Prompt Input

*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  background: #f9fafb;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 32px 16px;
}

.demo {
  width: 100%;
  max-width: 620px;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.pi-card {
  background: #fff;
  border: 1.5px solid #e5e7eb;
  border-radius: 16px;
  overflow: hidden;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.06);
  transition: border-color 0.15s, box-shadow 0.15s;
}
.pi-card:focus-within {
  border-color: #6366f1;
  box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.12);
}

.pi-top {
  padding: 12px 14px 0;
}

.model-pill {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: #f3f4f6;
  border: none;
  border-radius: 20px;
  padding: 5px 12px;
  font-size: 12px;
  font-weight: 600;
  color: #374151;
  cursor: pointer;
  transition: background 0.15s;
}
.model-pill:hover {
  background: #e5e7eb;
}

.model-dot {
  width: 7px;
  height: 7px;
  background: #16a34a;
  border-radius: 50%;
}

.pi-textarea {
  width: 100%;
  padding: 12px 16px;
  border: none;
  outline: none;
  font-size: 15px;
  color: #111827;
  background: transparent;
  resize: none;
  font-family: inherit;
  line-height: 1.6;
  min-height: 80px;
  max-height: 260px;
  overflow-y: auto;
}
.pi-textarea::placeholder {
  color: #9ca3af;
}

.pi-footer {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 10px 14px 12px;
  border-top: 1px solid #f3f4f6;
}

.pi-limit {
  display: flex;
  align-items: center;
  gap: 8px;
  flex: 1;
}

.pi-limit-bar {
  flex: 1;
  height: 3px;
  background: #f3f4f6;
  border-radius: 2px;
  overflow: hidden;
}

.pi-limit-fill {
  height: 100%;
  background: #6366f1;
  border-radius: 2px;
  width: 0%;
  transition: width 0.1s, background 0.15s;
}
.pi-limit-fill.warn {
  background: #d97706;
}
.pi-limit-fill.over {
  background: #dc2626;
}

.pi-token-count {
  font-size: 11px;
  color: #9ca3af;
  white-space: nowrap;
}
.pi-token-count.warn {
  color: #d97706;
}
.pi-token-count.over {
  color: #dc2626;
  font-weight: 700;
}

.pi-actions {
  display: flex;
  align-items: center;
  gap: 6px;
}

.pi-icon-btn {
  width: 32px;
  height: 32px;
  background: none;
  border: 1px solid #e5e7eb;
  border-radius: 8px;
  color: #9ca3af;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: color 0.15s, border-color 0.15s;
}
.pi-icon-btn:hover {
  color: #374151;
  border-color: #d1d5db;
}

.pi-send-btn {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 8px 14px;
  background: #6366f1;
  color: #fff;
  border: none;
  border-radius: 8px;
  font-size: 13px;
  font-weight: 700;
  cursor: pointer;
  transition: opacity 0.15s;
}
.pi-send-btn:disabled {
  opacity: 0.4;
  cursor: not-allowed;
}
.pi-send-btn:not(:disabled):hover {
  opacity: 0.85;
}

.pi-hint {
  text-align: center;
  font-size: 12px;
  color: #9ca3af;
}
.pi-hint kbd {
  background: #f3f4f6;
  border: 1px solid #d1d5db;
  border-radius: 4px;
  padding: 1px 5px;
  font-size: 11px;
  color: #374151;
}

.pi-sent {
  text-align: center;
  font-size: 14px;
  font-weight: 600;
  color: #16a34a;
  padding: 8px;
  animation: fadeIn 0.2s ease;
}
@keyframes fadeIn {
  from {
    opacity: 0;
  }
  to {
    opacity: 1;
  }
}

const textarea = document.getElementById("piInput");
const limitFill = document.getElementById("limitFill");
const tokenCount = document.getElementById("tokenCount");
const sendBtn = document.getElementById("piSend");
const piSent = document.getElementById("piSent");
const MAX_TOKENS = 4096;

function estimateTokens(text) {
  return Math.ceil(text.length / 4);
}

textarea.addEventListener("input", () => {
  // Auto-resize
  textarea.style.height = "auto";
  textarea.style.height = Math.min(textarea.scrollHeight, 260) + "px";

  const tokens = estimateTokens(textarea.value);
  const pct = Math.min((tokens / MAX_TOKENS) * 100, 100);

  limitFill.style.width = pct + "%";
  limitFill.className = "pi-limit-fill" + (pct >= 100 ? " over" : pct >= 75 ? " warn" : "");

  tokenCount.textContent = `~${tokens} / ${MAX_TOKENS}`;
  tokenCount.className = "pi-token-count" + (pct >= 100 ? " over" : pct >= 75 ? " warn" : "");

  sendBtn.disabled = !textarea.value.trim() || tokens > MAX_TOKENS;
  piSent.hidden = true;
});

function doSend() {
  if (sendBtn.disabled) return;
  piSent.hidden = false;
  textarea.value = "";
  textarea.style.height = "auto";
  limitFill.style.width = "0%";
  tokenCount.textContent = "0 / 4096";
  sendBtn.disabled = true;
}

sendBtn.addEventListener("click", doSend);

textarea.addEventListener("keydown", (e) => {
  if ((e.metaKey || e.ctrlKey) && e.key === "Enter") {
    e.preventDefault();
    doSend();
  }
});

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8" />
  <meta name="viewport" content="width=device-width, initial-scale=1.0" />
  <title>Prompt Input</title>
  <link rel="stylesheet" href="style.css" />
</head>
<body>
<div class="demo">
  <div class="pi-card">
    <div class="pi-top">
      <button class="model-pill" id="modelPill">
        <span class="model-dot"></span>
        <span id="modelName">Claude Sonnet</span>
        <svg width="10" height="10" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2.5"><polyline points="6 9 12 15 18 9"/></svg>
      </button>
    </div>

    <textarea class="pi-textarea" id="piInput" placeholder="Ask anything… (⌘+Enter to send)" rows="3"></textarea>

    <div class="pi-footer">
      <div class="pi-limit">
        <div class="pi-limit-bar" id="limitBar">
          <div class="pi-limit-fill" id="limitFill"></div>
        </div>
        <span class="pi-token-count" id="tokenCount">0 / 4096</span>
      </div>
      <div class="pi-actions">
        <button class="pi-icon-btn" id="attachBtn" title="Attach file">
          <svg width="16" height="16" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2"><path d="M21.44 11.05l-9.19 9.19a6 6 0 0 1-8.49-8.49l9.19-9.19a4 4 0 0 1 5.66 5.66l-9.2 9.19a2 2 0 0 1-2.83-2.83l8.49-8.48"/></svg>
        </button>
        <button class="pi-send-btn" id="piSend" disabled>
          <svg width="14" height="14" viewBox="0 0 24 24" fill="currentColor"><path d="M2.01 21L23 12 2.01 3 2 10l15 2-15 2z"/></svg>
          <span>Send</span>
        </button>
      </div>
    </div>
  </div>

  <div class="pi-hint">Press <kbd>⌘</kbd><kbd>Enter</kbd> to send · <kbd>Shift</kbd><kbd>Enter</kbd> for newline</div>

  <div class="pi-sent" id="piSent" hidden>
    <span>✓ Sent!</span>
  </div>
</div>
<script src="script.js"></script>
</body>
</html>

import { useState, useRef, useEffect } from "react";

const MODELS = ["claude-opus-4", "claude-sonnet-4", "gpt-4o", "gemini-2.0"];
const MAX_TOKENS = 4096;
const CHARS_PER_TOKEN = 4;

function estimateTokens(text: string) {
  return Math.ceil(text.length / CHARS_PER_TOKEN);
}

interface Attachment {
  id: number;
  name: string;
  size: string;
}

let fileId = 0;
const DEMO_FILES = [
  { name: "context.pdf", size: "128 KB" },
  { name: "data.csv", size: "42 KB" },
  { name: "screenshot.png", size: "1.1 MB" },
  { name: "schema.json", size: "8 KB" },
];

export default function PromptInputRC() {
  const [text, setText] = useState("");
  const [model, setModel] = useState(MODELS[0]);
  const [showModelMenu, setShowModelMenu] = useState(false);
  const [attachments, setAttachments] = useState<Attachment[]>([]);
  const [submitted, setSubmitted] = useState<string | null>(null);
  const taRef = useRef<HTMLTextAreaElement>(null);
  const demoIdx = useRef(0);

  const tokens = estimateTokens(text);
  const pct = Math.min((tokens / MAX_TOKENS) * 100, 100);
  const atLimit = tokens >= MAX_TOKENS;

  // Auto-resize textarea
  useEffect(() => {
    const ta = taRef.current;
    if (!ta) return;
    ta.style.height = "auto";
    ta.style.height = Math.min(ta.scrollHeight, 240) + "px";
  }, [text]);

  const handleKey = (e: React.KeyboardEvent) => {
    if ((e.metaKey || e.ctrlKey) && e.key === "Enter") {
      e.preventDefault();
      submit();
    }
  };

  const submit = () => {
    if (!text.trim() || atLimit) return;
    setSubmitted(text.trim());
    setText("");
    setAttachments([]);
    setTimeout(() => setSubmitted(null), 3000);
  };

  const addFile = () => {
    const demo = DEMO_FILES[demoIdx.current % DEMO_FILES.length];
    demoIdx.current++;
    setAttachments((prev) => [...prev, { id: ++fileId, ...demo }]);
  };

  const barColor = pct > 90 ? "bg-red-500" : pct > 70 ? "bg-yellow-400" : "bg-[#58a6ff]";

  return (
    <div className="min-h-screen bg-[#0d1117] p-6 flex justify-center items-center">
      <div className="w-full max-w-[680px] space-y-4">
        {submitted && (
          <div className="flex items-center gap-2 px-4 py-3 bg-green-500/10 border border-green-500/30 rounded-xl text-[12px] text-green-400">
            <svg
              width="14"
              height="14"
              viewBox="0 0 24 24"
              fill="none"
              stroke="currentColor"
              strokeWidth="2.5"
            >
              <polyline points="20 6 9 17 4 12" />
            </svg>
            Prompt submitted: "{submitted.slice(0, 60)}
            {submitted.length > 60 ? "…" : ""}"
          </div>
        )}

        <div className="bg-[#161b22] border border-[#30363d] rounded-2xl overflow-hidden focus-within:border-[#58a6ff] transition-colors">
          {/* Attachments */}
          {attachments.length > 0 && (
            <div className="flex flex-wrap gap-2 px-4 pt-3">
              {attachments.map((f) => (
                <div
                  key={f.id}
                  className="flex items-center gap-1.5 px-2.5 py-1 bg-[#21262d] border border-[#30363d] rounded-lg text-[11px] text-[#8b949e]"
                >
                  <svg
                    width="11"
                    height="11"
                    viewBox="0 0 24 24"
                    fill="none"
                    stroke="currentColor"
                    strokeWidth="2"
                  >
                    <path d="M14 2H6a2 2 0 0 0-2 2v16a2 2 0 0 0 2 2h12a2 2 0 0 0 2-2V8z" />
                    <polyline points="14 2 14 8 20 8" />
                  </svg>
                  <span>{f.name}</span>
                  <span className="text-[#484f58]">{f.size}</span>
                  <button
                    onClick={() => setAttachments((p) => p.filter((x) => x.id !== f.id))}
                    className="text-[#484f58] hover:text-[#e6edf3] ml-0.5 transition-colors"
                  >
                    ×
                  </button>
                </div>
              ))}
            </div>
          )}

          {/* Textarea */}
          <textarea
            ref={taRef}
            value={text}
            onChange={(e) => setText(e.target.value)}
            onKeyDown={handleKey}
            placeholder="Ask anything… (⌘+Enter to send)"
            className="w-full bg-transparent px-4 pt-3 pb-2 text-[14px] text-[#e6edf3] placeholder-[#484f58] resize-none outline-none leading-relaxed min-h-[80px]"
            style={{ height: "80px" }}
          />

          {/* Token bar */}
          <div className="h-0.5 mx-4 mb-0 bg-[#21262d] rounded-full overflow-hidden">
            <div
              className={`h-full ${barColor} transition-all duration-200 rounded-full`}
              style={{ width: `${pct}%` }}
            />
          </div>

          {/* Footer */}
          <div className="flex items-center justify-between px-4 py-2.5">
            <div className="flex items-center gap-2">
              {/* Attach */}
              <button
                onClick={addFile}
                title="Attach file"
                className="p-1.5 rounded-lg text-[#8b949e] hover:text-[#e6edf3] hover:bg-white/[0.04] transition-colors"
              >
                <svg
                  width="15"
                  height="15"
                  viewBox="0 0 24 24"
                  fill="none"
                  stroke="currentColor"
                  strokeWidth="2"
                >
                  <path d="M21.44 11.05l-9.19 9.19a6 6 0 0 1-8.49-8.49l9.19-9.19a4 4 0 0 1 5.66 5.66l-9.2 9.19a2 2 0 0 1-2.83-2.83l8.49-8.48" />
                </svg>
              </button>

              {/* Model selector */}
              <div className="relative">
                <button
                  onClick={() => setShowModelMenu((v) => !v)}
                  className="flex items-center gap-1.5 px-2.5 py-1 bg-[#21262d] border border-[#30363d] rounded-lg text-[11px] font-semibold text-[#8b949e] hover:text-[#e6edf3] hover:border-[#8b949e] transition-colors"
                >
                  <span className="w-1.5 h-1.5 rounded-full bg-[#58a6ff]" />
                  {model}
                  <svg
                    width="10"
                    height="10"
                    viewBox="0 0 24 24"
                    fill="none"
                    stroke="currentColor"
                    strokeWidth="2"
                  >
                    <polyline points="6 9 12 15 18 9" />
                  </svg>
                </button>
                {showModelMenu && (
                  <div className="absolute bottom-full mb-1 left-0 bg-[#21262d] border border-[#30363d] rounded-xl py-1 z-10 min-w-[170px] shadow-xl">
                    {MODELS.map((m) => (
                      <button
                        key={m}
                        onClick={() => {
                          setModel(m);
                          setShowModelMenu(false);
                        }}
                        className={`w-full text-left px-3 py-1.5 text-[12px] transition-colors flex items-center gap-2 ${
                          m === model
                            ? "text-[#58a6ff]"
                            : "text-[#8b949e] hover:text-[#e6edf3] hover:bg-white/[0.04]"
                        }`}
                      >
                        {m === model && (
                          <svg
                            width="10"
                            height="10"
                            viewBox="0 0 24 24"
                            fill="none"
                            stroke="currentColor"
                            strokeWidth="2.5"
                          >
                            <polyline points="20 6 9 17 4 12" />
                          </svg>
                        )}
                        {m !== model && <span className="w-2.5" />}
                        {m}
                      </button>
                    ))}
                  </div>
                )}
              </div>
            </div>

            <div className="flex items-center gap-3">
              {/* Token count */}
              <span
                className={`text-[11px] font-mono ${atLimit ? "text-red-400" : "text-[#484f58]"}`}
              >
                {tokens.toLocaleString()} / {MAX_TOKENS.toLocaleString()}
              </span>

              {/* Submit */}
              <button
                onClick={submit}
                disabled={!text.trim() || atLimit}
                className="flex items-center gap-1.5 px-3 py-1.5 bg-[#58a6ff] rounded-lg text-[12px] font-semibold text-white disabled:opacity-30 disabled:cursor-not-allowed hover:bg-[#79b8ff] transition-colors"
              >
                Send
                <svg
                  width="11"
                  height="11"
                  viewBox="0 0 24 24"
                  fill="none"
                  stroke="currentColor"
                  strokeWidth="2.5"
                  strokeLinecap="round"
                >
                  <line x1="22" y1="2" x2="11" y2="13" />
                  <polygon points="22 2 15 22 11 13 2 9 22 2" />
                </svg>
              </button>
            </div>
          </div>
        </div>
      </div>
    </div>
  );
}

<script setup>
import { ref, computed, watch, nextTick } from "vue";

const MODELS = ["claude-opus-4", "claude-sonnet-4", "gpt-4o", "gemini-2.0"];
const MAX_TOKENS = 4096;
const CHARS_PER_TOKEN = 4;
const DEMO_FILES = [
  { name: "context.pdf", size: "128 KB" },
  { name: "data.csv", size: "42 KB" },
  { name: "screenshot.png", size: "1.1 MB" },
  { name: "schema.json", size: "8 KB" },
];

const text = ref("");
const model = ref(MODELS[0]);
const showModelMenu = ref(false);
const attachments = ref([]);
const submitted = ref(null);
const taRef = ref(null);
let demoIdx = 0;
let fileId = 0;

function estimateTokens(t) {
  return Math.ceil(t.length / CHARS_PER_TOKEN);
}

const tokens = computed(() => estimateTokens(text.value));
const pct = computed(() => Math.min((tokens.value / MAX_TOKENS) * 100, 100));
const atLimit = computed(() => tokens.value >= MAX_TOKENS);
const barColor = computed(() =>
  pct.value > 90 ? "bg-red-500" : pct.value > 70 ? "bg-yellow-400" : "bg-[#58a6ff]"
);

watch(text, () => {
  nextTick(() => {
    const ta = taRef.value;
    if (!ta) return;
    ta.style.height = "auto";
    ta.style.height = Math.min(ta.scrollHeight, 240) + "px";
  });
});

function handleKey(e) {
  if ((e.metaKey || e.ctrlKey) && e.key === "Enter") {
    e.preventDefault();
    submit();
  }
}

function submit() {
  if (!text.value.trim() || atLimit.value) return;
  submitted.value = text.value.trim();
  text.value = "";
  attachments.value = [];
  setTimeout(() => (submitted.value = null), 3000);
}

function addFile() {
  const demo = DEMO_FILES[demoIdx % DEMO_FILES.length];
  demoIdx++;
  fileId++;
  attachments.value = [...attachments.value, { id: fileId, ...demo }];
}

function removeFile(id) {
  attachments.value = attachments.value.filter((x) => x.id !== id);
}

function selectModel(m) {
  model.value = m;
  showModelMenu.value = false;
}
</script>

<template>
  <div class="min-h-screen bg-[#0d1117] p-6 flex justify-center items-center">
    <div class="w-full max-w-[680px] space-y-4">
      <div
        v-if="submitted"
        class="flex items-center gap-2 px-4 py-3 bg-green-500/10 border border-green-500/30 rounded-xl text-[12px] text-green-400"
      >
        <svg width="14" height="14" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2.5"><polyline points="20 6 9 17 4 12"/></svg>
        Prompt submitted: "{{ submitted.slice(0, 60) }}{{ submitted.length > 60 ? '...' : '' }}"
      </div>

      <div class="bg-[#161b22] border border-[#30363d] rounded-2xl overflow-hidden focus-within:border-[#58a6ff] transition-colors">
        <!-- Attachments -->
        <div v-if="attachments.length > 0" class="flex flex-wrap gap-2 px-4 pt-3">
          <div
            v-for="f in attachments"
            :key="f.id"
            class="flex items-center gap-1.5 px-2.5 py-1 bg-[#21262d] border border-[#30363d] rounded-lg text-[11px] text-[#8b949e]"
          >
            <svg width="11" height="11" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2"><path d="M14 2H6a2 2 0 0 0-2 2v16a2 2 0 0 0 2 2h12a2 2 0 0 0 2-2V8z"/><polyline points="14 2 14 8 20 8"/></svg>
            <span>{{ f.name }}</span>
            <span class="text-[#484f58]">{{ f.size }}</span>
            <button @click="removeFile(f.id)" class="text-[#484f58] hover:text-[#e6edf3] ml-0.5 transition-colors">
              x
            </button>
          </div>
        </div>

        <!-- Textarea -->
        <textarea
          ref="taRef"
          v-model="text"
          @keydown="handleKey"
          placeholder="Ask anything... (Cmd+Enter to send)"
          class="w-full bg-transparent px-4 pt-3 pb-2 text-[14px] text-[#e6edf3] placeholder-[#484f58] resize-none outline-none leading-relaxed min-h-[80px]"
          style="height: 80px"
        />

        <!-- Token bar -->
        <div class="h-0.5 mx-4 mb-0 bg-[#21262d] rounded-full overflow-hidden">
          <div
            :class="['h-full transition-all duration-200 rounded-full', barColor]"
            :style="{ width: pct + '%' }"
          />
        </div>

        <!-- Footer -->
        <div class="flex items-center justify-between px-4 py-2.5">
          <div class="flex items-center gap-2">
            <!-- Attach -->
            <button
              @click="addFile"
              title="Attach file"
              class="p-1.5 rounded-lg text-[#8b949e] hover:text-[#e6edf3] hover:bg-white/[0.04] transition-colors"
            >
              <svg width="15" height="15" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2">
                <path d="M21.44 11.05l-9.19 9.19a6 6 0 0 1-8.49-8.49l9.19-9.19a4 4 0 0 1 5.66 5.66l-9.2 9.19a2 2 0 0 1-2.83-2.83l8.49-8.48"/>
              </svg>
            </button>

            <!-- Model selector -->
            <div class="relative">
              <button
                @click="showModelMenu = !showModelMenu"
                class="flex items-center gap-1.5 px-2.5 py-1 bg-[#21262d] border border-[#30363d] rounded-lg text-[11px] font-semibold text-[#8b949e] hover:text-[#e6edf3] hover:border-[#8b949e] transition-colors"
              >
                <span class="w-1.5 h-1.5 rounded-full bg-[#58a6ff]" />
                {{ model }}
                <svg width="10" height="10" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2"><polyline points="6 9 12 15 18 9"/></svg>
              </button>
              <div v-if="showModelMenu" class="absolute bottom-full mb-1 left-0 bg-[#21262d] border border-[#30363d] rounded-xl py-1 z-10 min-w-[170px] shadow-xl">
                <button
                  v-for="m in MODELS"
                  :key="m"
                  @click="selectModel(m)"
                  :class="['w-full text-left px-3 py-1.5 text-[12px] transition-colors flex items-center gap-2', m === model ? 'text-[#58a6ff]' : 'text-[#8b949e] hover:text-[#e6edf3] hover:bg-white/[0.04]']"
                >
                  <svg v-if="m === model" width="10" height="10" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2.5"><polyline points="20 6 9 17 4 12"/></svg>
                  <span v-else class="w-2.5" />
                  {{ m }}
                </button>
              </div>
            </div>
          </div>

          <div class="flex items-center gap-3">
            <!-- Token count -->
            <span :class="['text-[11px] font-mono', atLimit ? 'text-red-400' : 'text-[#484f58]']">
              {{ tokens.toLocaleString() }} / {{ MAX_TOKENS.toLocaleString() }}
            </span>

            <!-- Submit -->
            <button
              @click="submit"
              :disabled="!text.trim() || atLimit"
              class="flex items-center gap-1.5 px-3 py-1.5 bg-[#58a6ff] rounded-lg text-[12px] font-semibold text-white disabled:opacity-30 disabled:cursor-not-allowed hover:bg-[#79b8ff] transition-colors"
            >
              Send
              <svg width="11" height="11" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2.5" stroke-linecap="round">
                <line x1="22" y1="2" x2="11" y2="13"/><polygon points="22 2 15 22 11 13 2 9 22 2"/>
              </svg>
            </button>
          </div>
        </div>
      </div>
    </div>
  </div>
</template>

<style scoped>
</style>

<script>
import { afterUpdate } from "svelte";

const MODELS = ["claude-opus-4", "claude-sonnet-4", "gpt-4o", "gemini-2.0"];
const MAX_TOKENS = 4096;
const CHARS_PER_TOKEN = 4;
const DEMO_FILES = [
  { name: "context.pdf", size: "128 KB" },
  { name: "data.csv", size: "42 KB" },
  { name: "screenshot.png", size: "1.1 MB" },
  { name: "schema.json", size: "8 KB" },
];

let text = "";
let model = MODELS[0];
let showModelMenu = false;
let attachments = [];
let submitted = null;
let taEl;
let demoIdx = 0;
let fileId = 0;

function estimateTokens(t) {
  return Math.ceil(t.length / CHARS_PER_TOKEN);
}

$: tokens = estimateTokens(text);
$: pct = Math.min((tokens / MAX_TOKENS) * 100, 100);
$: atLimit = tokens >= MAX_TOKENS;
$: barColor = pct > 90 ? "bg-red-500" : pct > 70 ? "bg-yellow-400" : "bg-[#58a6ff]";

afterUpdate(() => {
  if (taEl) {
    taEl.style.height = "auto";
    taEl.style.height = Math.min(taEl.scrollHeight, 240) + "px";
  }
});

function handleKey(e) {
  if ((e.metaKey || e.ctrlKey) && e.key === "Enter") {
    e.preventDefault();
    submit();
  }
}

function submit() {
  if (!text.trim() || atLimit) return;
  submitted = text.trim();
  text = "";
  attachments = [];
  setTimeout(() => (submitted = null), 3000);
}

function addFile() {
  const demo = DEMO_FILES[demoIdx % DEMO_FILES.length];
  demoIdx++;
  fileId++;
  attachments = [...attachments, { id: fileId, ...demo }];
}

function removeFile(id) {
  attachments = attachments.filter((x) => x.id !== id);
}

function selectModel(m) {
  model = m;
  showModelMenu = false;
}
</script>

<div class="min-h-screen bg-[#0d1117] p-6 flex justify-center items-center">
  <div class="w-full max-w-[680px] space-y-4">
    {#if submitted}
      <div class="flex items-center gap-2 px-4 py-3 bg-green-500/10 border border-green-500/30 rounded-xl text-[12px] text-green-400">
        <svg width="14" height="14" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2.5"><polyline points="20 6 9 17 4 12"/></svg>
        Prompt submitted: "{submitted.slice(0, 60)}{submitted.length > 60 ? '...' : ''}"
      </div>
    {/if}

    <div class="bg-[#161b22] border border-[#30363d] rounded-2xl overflow-hidden focus-within:border-[#58a6ff] transition-colors">
      <!-- Attachments -->
      {#if attachments.length > 0}
        <div class="flex flex-wrap gap-2 px-4 pt-3">
          {#each attachments as f (f.id)}
            <div class="flex items-center gap-1.5 px-2.5 py-1 bg-[#21262d] border border-[#30363d] rounded-lg text-[11px] text-[#8b949e]">
              <svg width="11" height="11" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2"><path d="M14 2H6a2 2 0 0 0-2 2v16a2 2 0 0 0 2 2h12a2 2 0 0 0 2-2V8z"/><polyline points="14 2 14 8 20 8"/></svg>
              <span>{f.name}</span>
              <span class="text-[#484f58]">{f.size}</span>
              <button on:click={() => removeFile(f.id)} class="text-[#484f58] hover:text-[#e6edf3] ml-0.5 transition-colors">
                x
              </button>
            </div>
          {/each}
        </div>
      {/if}

      <!-- Textarea -->
      <textarea
        bind:this={taEl}
        bind:value={text}
        on:keydown={handleKey}
        placeholder="Ask anything... (Cmd+Enter to send)"
        class="w-full bg-transparent px-4 pt-3 pb-2 text-[14px] text-[#e6edf3] placeholder-[#484f58] resize-none outline-none leading-relaxed min-h-[80px]"
        style="height: 80px;"
      />

      <!-- Token bar -->
      <div class="h-0.5 mx-4 mb-0 bg-[#21262d] rounded-full overflow-hidden">
        <div
          class="h-full {barColor} transition-all duration-200 rounded-full"
          style="width: {pct}%;"
        />
      </div>

      <!-- Footer -->
      <div class="flex items-center justify-between px-4 py-2.5">
        <div class="flex items-center gap-2">
          <!-- Attach -->
          <button
            on:click={addFile}
            title="Attach file"
            class="p-1.5 rounded-lg text-[#8b949e] hover:text-[#e6edf3] hover:bg-white/[0.04] transition-colors"
          >
            <svg width="15" height="15" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2">
              <path d="M21.44 11.05l-9.19 9.19a6 6 0 0 1-8.49-8.49l9.19-9.19a4 4 0 0 1 5.66 5.66l-9.2 9.19a2 2 0 0 1-2.83-2.83l8.49-8.48"/>
            </svg>
          </button>

          <!-- Model selector -->
          <div class="relative">
            <button
              on:click={() => (showModelMenu = !showModelMenu)}
              class="flex items-center gap-1.5 px-2.5 py-1 bg-[#21262d] border border-[#30363d] rounded-lg text-[11px] font-semibold text-[#8b949e] hover:text-[#e6edf3] hover:border-[#8b949e] transition-colors"
            >
              <span class="w-1.5 h-1.5 rounded-full bg-[#58a6ff]" />
              {model}
              <svg width="10" height="10" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2"><polyline points="6 9 12 15 18 9"/></svg>
            </button>
            {#if showModelMenu}
              <div class="absolute bottom-full mb-1 left-0 bg-[#21262d] border border-[#30363d] rounded-xl py-1 z-10 min-w-[170px] shadow-xl">
                {#each MODELS as m}
                  <button
                    on:click={() => selectModel(m)}
                    class="w-full text-left px-3 py-1.5 text-[12px] transition-colors flex items-center gap-2 {m === model ? 'text-[#58a6ff]' : 'text-[#8b949e] hover:text-[#e6edf3] hover:bg-white/[0.04]'}"
                  >
                    {#if m === model}
                      <svg width="10" height="10" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2.5"><polyline points="20 6 9 17 4 12"/></svg>
                    {:else}
                      <span class="w-2.5" />
                    {/if}
                    {m}
                  </button>
                {/each}
              </div>
            {/if}
          </div>
        </div>

        <div class="flex items-center gap-3">
          <!-- Token count -->
          <span class="text-[11px] font-mono {atLimit ? 'text-red-400' : 'text-[#484f58]'}">
            {tokens.toLocaleString()} / {MAX_TOKENS.toLocaleString()}
          </span>

          <!-- Submit -->
          <button
            on:click={submit}
            disabled={!text.trim() || atLimit}
            class="flex items-center gap-1.5 px-3 py-1.5 bg-[#58a6ff] rounded-lg text-[12px] font-semibold text-white disabled:opacity-30 disabled:cursor-not-allowed hover:bg-[#79b8ff] transition-colors"
          >
            Send
            <svg width="11" height="11" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2.5" stroke-linecap="round">
              <line x1="22" y1="2" x2="11" y2="13"/><polygon points="22 2 15 22 11 13 2 9 22 2"/>
            </svg>
          </button>
        </div>
      </div>
    </div>
  </div>
</div>