"use client";

import { Suspense, useCallback, useEffect, useState } from "react";
import { JM, JV } from "@/components/project-creation/modal-theme";
import { AtlasChat } from "@/components/AtlasChat";
import {
  BuildLivePlanPanel,
  addSectionContextRef,
} from "@/components/project-main/BuildLivePlanPanel";
import {
  type ChatContextRef,
  contextRefKey,
} from "@/lib/chat-context-refs";

export function MvpSetupDescribeView({ projectId, workspace }: { projectId: string; workspace: string }) {
  const [chatContextRefs, setChatContextRefs] = useState<ChatContextRef[]>([]);
  const [tab, setTab] = useState<"chat" | "plan">("chat");
  const [narrow, setNarrow] = useState(false);

  useEffect(() => {
    const mq = window.matchMedia("(max-width: 900px)");
    const apply = () => setNarrow(mq.matches);
    apply();
    mq.addEventListener("change", apply);
    return () => mq.removeEventListener("change", apply);
  }, []);

  const removeChatContextRef = useCallback((key: string) => {
    setChatContextRefs(prev => prev.filter(r => contextRefKey(r) !== key));
  }, []);

  const addPlanSectionToChat = useCallback((label: string, phaseId: string | null) => {
    setChatContextRefs(prev => addSectionContextRef(prev, label, phaseId));
  }, []);

  return (
    <div style={{ flex: 1, display: "flex", flexDirection: "column", minHeight: 0, background: JV.chatColumnBg }}>
      <div
        style={{
          padding: "18px 28px 14px",
          background: "#fff",
          borderBottom: `1px solid ${JM.border}`,
          flexShrink: 0,
        }}
      >
        <div style={{ fontSize: 17, fontWeight: 700, color: JM.ink, marginBottom: 3, fontFamily: JM.fontDisplay }}>
          Describe
        </div>
        <div style={{ fontSize: 12.5, color: JM.muted }}>
          Tell Vibn about your idea — your plan fills in on the right as you go.
        </div>
      </div>

      {narrow && (
        <div
          style={{
            display: "flex",
            borderBottom: `1px solid ${JM.border}`,
            background: "#EEF0FF",
            flexShrink: 0,
          }}
        >
          {(["chat", "plan"] as const).map(id => (
            <button
              key={id}
              type="button"
              onClick={() => setTab(id)}
              style={{
                flex: 1,
                padding: "11px 8px",
                border: "none",
                background: "transparent",
                fontSize: 13,
                fontWeight: tab === id ? 600 : 500,
                color: tab === id ? JM.indigo : JM.muted,
                borderBottom: tab === id ? `2px solid ${JM.indigo}` : "2px solid transparent",
                cursor: "pointer",
                fontFamily: JM.fontSans,
              }}
            >
              {id === "chat" ? "Chat" : "Your plan"}
            </button>
          ))}
        </div>
      )}

      <div style={{ flex: 1, display: "flex", minHeight: 0, overflow: "hidden" }}>
        <div
          style={{
            flex: 1,
            minWidth: 0,
            display: narrow && tab !== "chat" ? "none" : "flex",
            flexDirection: "column",
          }}
        >
          <AtlasChat
            projectId={projectId}
            conversationScope="overview"
            contextEmptyLabel="Plan"
            emptyStateHint="Answer Vibn’s questions — each phase you complete updates your plan."
            chatContextRefs={chatContextRefs}
            onRemoveChatContextRef={removeChatContextRef}
          />
        </div>
        <div
          style={{
            width: narrow ? undefined : 308,
            flex: narrow && tab === "plan" ? 1 : undefined,
            flexShrink: 0,
            minWidth: 0,
            display: narrow && tab !== "plan" ? "none" : "flex",
            flexDirection: "column",
            overflow: "hidden",
          }}
        >
          <Suspense fallback={<div style={{ flex: 1, background: JV.prdPanelBg }} />}>
            <BuildLivePlanPanel
              projectId={projectId}
              workspace={workspace}
              chatContextRefs={chatContextRefs}
              onAddSectionRef={addPlanSectionToChat}
              compactHeader={narrow}
            />
          </Suspense>
        </div>
      </div>
    </div>
  );
}