import { memo, useState, useCallback } from "react";
import { marked } from "marked";
import type { ChatTurn as ChatTurnType, ChatTurnBlockTool } from "../lib/api";
import ToolCallDisplay from "./ToolCallDisplay";

interface ChatTurnProps {
  turn: ChatTurnType;
}

// Configure marked with breaks enabled
marked.use({
  breaks: true,
});

const ChatTurn = memo(function ChatTurn({ turn }: ChatTurnProps) {
  const formatDuration = (ms: number): string => {
    if (ms < 1000) return `${ms}ms`;
    const seconds = (ms / 1000).toFixed(1);
    return `${seconds}s`;
  };

  const formatTokenCount = (count: number): string => {
    if (count >= 1000) {
      return `${(count / 1000).toFixed(1)}k`;
    }
    return count.toString();
  };

  const modelId = turn.llm || "Unknown";
  const modeLabel =
    turn.mode?.charAt(0).toUpperCase() + turn.mode?.slice(1) || "Unknown";
  const statusLabel =
    turn.status?.charAt(0).toUpperCase() + turn.status?.slice(1) || "Unknown";
  const startedAt = new Date(turn.createdAt);

  return (
    <div id={`turn-${turn._id}`} className="border-b border-border-subtle pb-4 last:border-b-0">
      {/* Turn Header */}
      <div className="flex items-center gap-4 text-xs text-text-muted mb-3 px-4">
        <div>{startedAt.toLocaleTimeString()}</div>
        <div className="flex items-center gap-2">
          <span className="font-mono">{modelId}</span>
        </div>
        <div className="w-px h-3 bg-border-subtle" />
        <div>{modeLabel}</div>
        <div className="w-px h-3 bg-border-subtle" />
        <div
          className={
            turn.status === "finished"
              ? "text-green-500"
              : turn.status === "error"
                ? "text-red-500"
                : turn.status === "aborted"
                  ? "text-yellow-500"
                  : "text-yellow-500"
          }
        >
          {statusLabel}
        </div>
        <div className="w-px h-3 bg-border-subtle" />
        {turn.stats && (
          <>
            <div className="w-px h-3 bg-border-subtle" />
            <div>{formatDuration(turn.stats.durationMs)}</div>
            <div className="w-px h-3 bg-border-subtle" />
            <div>
              {turn.stats.inputTokens
                ? formatTokenCount(turn.stats.inputTokens)
                : "0"}{" "}
              in /{" "}
              {turn.stats.responseTokens
                ? formatTokenCount(turn.stats.responseTokens)
                : "0"}{" "}
              out
            </div>
          </>
        )}
      </div>

      {/* Error Alert */}
      {turn.errorMessage && turn.status === "error" && (
        <div className="max-w-[80%] ml-0 mb-2">
          <div className="bg-red-600 text-white rounded p-3 border-2 border-red-400">
            <div className="text-xs font-semibold mb-1 flex items-center gap-2">
              <span>⚠️</span> Error
            </div>
            <div className="whitespace-pre-wrap text-sm">
              {turn.errorMessage}
            </div>
          </div>
        </div>
      )}

      {/* Aborted notice */}
      {turn.status === "aborted" && (
        <div className="max-w-[80%] ml-0 mb-2">
          <div className="bg-bg-tertiary border border-border-default rounded p-3">
            <div className="whitespace-pre-wrap text-sm text-text-secondary">
              The turn was aborted by you.
            </div>
          </div>
        </div>
      )}

      {/* User Prompt */}
      <div className="max-w-[80%] ml-0 mb-4">
        <div className="bg-[#4a0000] text-white rounded p-4">
          <div className="text-xs font-semibold mb-2">You</div>
          <div className="whitespace-pre-wrap text-sm">
            {turn.prompts?.user || ""}
          </div>
        </div>
      </div>

      {/* Agent Response */}
      {turn.blocks && turn.blocks.length > 0 && (
        <div className="max-w-[80%] ml-auto mb-4 overflow-x-hidden">
          <div className="bg-bg-tertiary border border-border-default rounded p-3 overflow-x-auto">
            <div className="text-xs font-semibold mb-4 text-text-secondary">
              Gadget
            </div>

            {/* Render blocks in order */}
            {turn.blocks.map((block, idx) => {
              if (block.mode === "thinking") {
                return (
                  <div key={idx} className="mb-4">
                    <div className="text-xs text-text-muted mb-1 font-mono">
                      Thinking
                    </div>
                    <div
                      className="gadget-markdown bg-bg-secondary rounded p-2 text-xs text-text-muted font-mono"
                      dangerouslySetInnerHTML={{
                        __html: marked.parse(block.content) as string,
                      }}
                    />
                  </div>
                );
              } else if (block.mode === "responding") {
                return (
                  <div key={idx} className="mb-4 overflow-x-auto">
                    <div
                      className="gadget-markdown text-[13px]"
                      dangerouslySetInnerHTML={{
                        __html: marked.parse(block.content) as string,
                      }}
                    />
                  </div>
                );
              } else if (block.mode === "tool") {
                const toolCall = block.content;
                const subagent = toolCall.subagent;
                return (
                  <div key={idx} className="tool-call">
                    <ToolCallDisplay
                      callId={toolCall.callId}
                      name={toolCall.name}
                      parameters={toolCall.parameters}
                      response={toolCall.response}
                      createdAt={block.createdAt}
                    />
                    {subagent && <SubagentDisplay subagent={subagent} />}
                  </div>
                );
              }
              return null;
            })}

            <div className="mt-1 text-xs text-text-muted">
              {startedAt.toLocaleTimeString()}
            </div>
          </div>
        </div>
      )}
    </div>
  );
});

function SubagentDisplay({
  subagent,
}: {
  subagent: NonNullable<ChatTurnBlockTool["content"]["subagent"]>;
}) {
  const [expanded, setExpanded] = useState(true);
  const toggle = useCallback(() => setExpanded((p) => !p), []);

  const formatDuration = (ms: number): string => {
    if (ms < 1000) return `${ms}ms`;
    const seconds = (ms / 1000).toFixed(1);
    return `${seconds}s`;
  };

  const formatTokenCount = (count: number): string => {
    if (count >= 1000) return `${(count / 1000).toFixed(1)}k`;
    return count.toString();
  };

  return (
    <div className="ml-3 border-l-2 border-brand/20 pl-1.5 mt-1">
      <button
        onClick={toggle}
        className="flex items-center gap-1.5 text-xs font-mono text-text-muted hover:text-text-primary transition-colors w-full text-left"
      >
        <span className="text-brand">▾</span>
        <span>Subagent</span>
        {subagent.stats && (
          <span className="text-text-muted">
            ({subagent.toolCalls.length} calls ·{" "}
            {formatDuration(subagent.stats.durationMs)})
          </span>
        )}
      </button>

      {expanded && (
        <div className="space-y-1">
          {/* Thinking */}
          {subagent.thinking && (
            <div>
              <div className="text-xs text-text-muted font-mono mb-0.5">
                Thinking
              </div>
              <div
                className="gadget-markdown bg-bg-secondary rounded p-1.5 text-xs text-text-muted font-mono"
                dangerouslySetInnerHTML={{
                  __html: marked.parse(subagent.thinking) as string,
                }}
              />
            </div>
          )}

          {/* Subagent Tool Calls */}
          {subagent.toolCalls.length > 0 && (
            <div>
              <div className="text-xs text-text-muted font-mono mb-0.5">
                Tool Calls ({subagent.toolCalls.length})
              </div>
              <div className="space-y-0.5">
                {subagent.toolCalls.map((tc, i) => (
                  <ToolCallDisplay
                    key={tc.callId || i}
                    callId={tc.callId}
                    name={tc.name}
                    parameters={tc.parameters}
                    response={tc.response}
                    defaultExpanded={false}
                  />
                ))}
              </div>
            </div>
          )}

          {/* Response */}
          {subagent.response && (
            <div>
              <div className="text-xs text-text-muted font-mono mb-0.5">
                Response
              </div>
              <div
                className="gadget-markdown text-xs"
                dangerouslySetInnerHTML={{
                  __html: marked.parse(subagent.response) as string,
                }}
              />
            </div>
          )}

          {/* Stats */}
          {subagent.stats && (
            <div className="flex gap-3 text-xs text-text-muted font-mono pt-1 border-t border-border-subtle">
              <span>{formatDuration(subagent.stats.durationMs)}</span>
              <span>{formatTokenCount(subagent.stats.inputTokens)} in</span>
              <span>{formatTokenCount(subagent.stats.responseTokens)} out</span>
              {subagent.stats.thinkingTokenCount > 0 && (
                <span>
                  {formatTokenCount(subagent.stats.thinkingTokenCount)} thinking
                </span>
              )}
            </div>
          )}
        </div>
      )}
    </div>
  );
}

export default ChatTurn;