"use client";

import {
  BookOpen,
  Calculator,
  ChevronDown,
  ChevronUp,
  Lightbulb,
  Target,
  Zap,
} from "lucide-react";
import { useState } from "react";
import type { DeepChapterOutput, VisualLessonOutput } from "@/lib/api/types";

export function DeepChapterCard({ data, topic }: { data: DeepChapterOutput; topic: string }) {
  const [expandedSections, setExpandedSections] = useState<Set<string>>(new Set(["concepts"]));
  const toggle = (key: string) => {
    setExpandedSections((prev) => {
      const next = new Set(prev);
      if (next.has(key)) next.delete(key);
      else next.add(key);
      return next;
    });
  };

  const dataLabel = data.data_source_label;
  const pyqPatterns = data.pyq_patterns ?? [];
  const hasRealPyq = pyqPatterns.some((p) => p.question && p.source === "Seen in uploaded PYQs");

  return (
    <article className="animate-msg-assistant w-full rounded-xl border border-white/[0.06] bg-[#080809] p-5">
      {/* Header */}
      <div className="mb-4 flex items-center gap-2.5">
        <BookOpen className="size-4 shrink-0 text-blue-400/70" />
        <div>
          <span className="text-[10px] font-medium uppercase tracking-[0.08em] text-white/22">Deep Chapter Teaching</span>
          <p className="text-[15px] font-semibold tracking-[-0.01em] text-white/95">{data.chapter_title || topic}</p>
        </div>
      </div>

      {/* Data source label */}
      {dataLabel && (
        <div className="mb-2 inline-flex items-center gap-1.5 rounded-md border border-white/[0.06] bg-white/[0.03] px-2 py-1">
          <span className="size-1.5 rounded-full bg-emerald-400/60" />
          <span className="text-[10px] text-white/40">{dataLabel}</span>
        </div>
      )}

      {/* Syllabus position */}
      <p className="mb-3 text-[11px] text-white/35">{data.syllabus_position}</p>

      {/* What this chapter is about */}
      {data.what_this_chapter_is_about && (
        <div className="mb-3 rounded-lg border border-white/[0.06] bg-white/[0.02] px-3 py-2.5">
          <p className="text-[13px] leading-[1.7] text-white/75">{data.what_this_chapter_is_about}</p>
        </div>
      )}

      {/* Prerequisites */}
      {data.prerequisite_topics?.length > 0 && (
        <CollapsibleSection
          title="Prerequisites"
          icon={<Target className="size-3" />}
          expanded={expandedSections.has("prereqs")}
          onToggle={() => toggle("prereqs")}
          count={data.prerequisite_topics.length}
        >
          <ul className="space-y-1">
            {data.prerequisite_topics.map((p, i) => (
              <li key={i} className="flex items-start gap-2 text-[12px] text-white/60">
                <span className="mt-1 size-1 shrink-0 rounded-full bg-blue-400/50" />
                {p}
              </li>
            ))}
          </ul>
        </CollapsibleSection>
      )}

      {/* Deep concept sections */}
      {data.deep_concept_sections?.length > 0 && (
        <CollapsibleSection
          title="Deep Teaching"
          icon={<Lightbulb className="size-3" />}
          expanded={expandedSections.has("concepts")}
          onToggle={() => toggle("concepts")}
          count={data.deep_concept_sections.length}
        >
          <div className="space-y-3">
            {data.deep_concept_sections.map((concept, i) => (
              <div key={i} className="rounded-lg border border-white/[0.04] bg-white/[0.01] p-3">
                <p className="text-[13px] font-semibold text-white/85">{concept.name}</p>
                <p className="mt-1 text-[12px] leading-[1.6] text-white/60">{concept.simple_explanation}</p>
                {concept.deep_explanation && (
                  <p className="mt-1 text-[12px] leading-[1.6] text-white/50">{concept.deep_explanation}</p>
                )}
                {concept.equation && (
                  <p className="mt-1 rounded bg-black/30 px-2 py-1 text-[12px] font-mono text-emerald-400/80">{concept.equation}</p>
                )}
                {concept.real_example && (
                  <p className="mt-1 text-[11px] text-white/40">Example: {concept.real_example}</p>
                )}
                {concept.common_mistake && (
                  <p className="mt-1 text-[11px] text-amber-400/60">Mistake: {concept.common_mistake}</p>
                )}
                {concept.practice_question && (
                  <p className="mt-1 text-[11px] text-white/55">Try: {concept.practice_question}</p>
                )}
              </div>
            ))}
          </div>
        </CollapsibleSection>
      )}

      {/* Derivations */}
      {data.derivations?.length > 0 && (
        <CollapsibleSection
          title="Derivations"
          icon={<Calculator className="size-3" />}
          expanded={expandedSections.has("derivations")}
          onToggle={() => toggle("derivations")}
          count={data.derivations.length}
        >
          <div className="space-y-3">
            {data.derivations.map((d, i) => (
              <div key={i} className="rounded-lg border border-emerald-500/10 bg-emerald-500/[0.03] p-3">
                <p className="text-[13px] font-semibold text-white/85">{d.name}</p>
                {d.symbols?.length > 0 && (
                  <p className="mt-1 text-[11px] text-white/40">Symbols: {d.symbols.join(", ")}</p>
                )}
                {d.steps?.length > 0 && (
                  <ol className="mt-2 space-y-1">
                    {d.steps.map((step, j) => (
                      <li key={j} className="flex items-start gap-2 text-[12px] text-white/60">
                        <span className="mt-0.5 text-[10px] text-white/30">{j + 1}.</span>
                        {step}
                      </li>
                    ))}
                  </ol>
                )}
                {d.final_formula && (
                  <p className="mt-2 rounded bg-black/30 px-2 py-1 text-[12px] font-mono text-emerald-400/80">{d.final_formula}</p>
                )}
                {d.unit_check && <p className="mt-1 text-[11px] text-white/40">{d.unit_check}</p>}
              </div>
            ))}
          </div>
        </CollapsibleSection>
      )}

      {/* Formulas */}
      {data.formulas?.length > 0 && (
        <CollapsibleSection
          title="Formulas"
          icon={<Zap className="size-3" />}
          expanded={expandedSections.has("formulas")}
          onToggle={() => toggle("formulas")}
          count={data.formulas.length}
        >
          <div className="space-y-1.5">
            {data.formulas.map((f, i) => (
              <div key={i} className="flex items-start gap-2 rounded-lg border border-white/[0.04] bg-white/[0.01] px-3 py-2">
                <span className="min-w-0 flex-1 text-[12px] text-white/70">{f.name}</span>
                <span className="shrink-0 font-mono text-[11px] text-emerald-400/70">{f.formula}</span>
                <span className="shrink-0 text-[10px] text-white/30">[{f.unit}]</span>
              </div>
            ))}
          </div>
        </CollapsibleSection>
      )}

      {/* Common mistakes */}
      {data.common_mistakes?.length > 0 && (
        <CollapsibleSection
          title="Common Mistakes"
          expanded={expandedSections.has("mistakes")}
          onToggle={() => toggle("mistakes")}
          count={data.common_mistakes.length}
        >
          <ul className="space-y-1">
            {data.common_mistakes.map((m, i) => (
              <li key={i} className="flex items-start gap-2 text-[12px] text-amber-400/60">
                <span className="mt-1 size-1 shrink-0 rounded-full bg-amber-400/50" />
                {m}
              </li>
            ))}
          </ul>
        </CollapsibleSection>
      )}

      {/* Important questions */}
      {data.important_questions?.length > 0 && (
        <CollapsibleSection
          title="Important Questions"
          expanded={expandedSections.has("important")}
          onToggle={() => toggle("important")}
          count={data.important_questions.length}
        >
          <ul className="space-y-1">
            {data.important_questions.map((q, i) => (
              <li key={i} className="flex items-start gap-2 text-[12px] text-white/60">
                <span className="mt-1 size-1 shrink-0 rounded-full bg-white/45" />
                {q}
              </li>
            ))}
          </ul>
        </CollapsibleSection>
      )}

      {/* PYQ */}
      {hasRealPyq ? (
        <CollapsibleSection
          title="PYQ Patterns (Uploaded Papers)"
          expanded={expandedSections.has("pyq")}
          onToggle={() => toggle("pyq")}
          count={pyqPatterns.filter((p) => p.question).length}
        >
          <div className="space-y-1.5">
            {pyqPatterns.filter((p) => p.question).map((p, i) => (
              <div key={i} className="rounded-lg border border-white/[0.04] bg-white/[0.01] px-3 py-2">
                <p className="text-[12px] text-white/70">{p.question}</p>
                <div className="mt-0.5 flex items-center gap-2">
                  <span className="text-[10px] text-white/35">{p.marks} marks — {p.year}</span>
                  {p.source === "Seen in uploaded PYQs" && (
                    <span className="rounded bg-emerald-500/10 px-1.5 py-0.5 text-[9px] text-emerald-400/70">Uploaded PYQ</span>
                  )}
                </div>
              </div>
            ))}
          </div>
        </CollapsibleSection>
      ) : (
        <div className="mt-3 rounded-lg border border-amber-500/10 bg-amber-500/[0.03] px-3 py-2.5">
          <p className="text-[11px] font-medium text-amber-400/70">Upload previous year papers to unlock pattern analysis across them.</p>
          <p className="mt-1 text-[10px] text-amber-400/50">Upload previous year question papers to see repeated topics, marks distribution, and evidence-backed insights.</p>
        </div>
      )}

      {/* Quick revision */}
      {data.quick_revision_box?.length > 0 && (
        <div className="mt-3 rounded-lg border border-blue-500/10 bg-blue-500/[0.03] px-3 py-2.5">
          <p className="mb-1.5 text-[10px] font-medium uppercase tracking-[0.08em] text-blue-400/50">Quick Revision</p>
          <ul className="space-y-1">
            {data.quick_revision_box.map((r, i) => (
              <li key={i} className="text-[12px] text-white/60">{r}</li>
            ))}
          </ul>
        </div>
      )}

      {/* Practice */}
      {data.practice_questions?.length > 0 && (
        <div className="mt-3 rounded-lg border border-white/[0.1] bg-white/[0.03] px-3 py-2.5">
          <p className="mb-1.5 text-[10px] font-medium uppercase tracking-[0.08em] text-white/50">Practice</p>
          <ul className="space-y-1">
            {data.practice_questions.map((q, i) => (
              <li key={i} className="text-[12px] text-white/60">{q}</li>
            ))}
          </ul>
        </div>
      )}

      {/* Next action */}
      {data.next_best_action && (
        <div className="mt-3 rounded-lg border border-emerald-500/10 bg-emerald-500/[0.03] px-3 py-2.5">
          <p className="text-[12px] text-emerald-400/70">{data.next_best_action}</p>
        </div>
      )}

      {/* Source */}
      {data.source_used && (
        <p className="mt-3 text-[10px] text-white/25">Source: {data.source_used}</p>
      )}
    </article>
  );
}

export function VisualLessonCard({ data, topic }: { data: VisualLessonOutput; topic: string }) {
  const [expandedFrames, setExpandedFrames] = useState<Set<string>>(new Set(["derivation"]));
  const toggle = (key: string) => {
    setExpandedFrames((prev) => {
      const next = new Set(prev);
      if (next.has(key)) next.delete(key);
      else next.add(key);
      return next;
    });
  };

  const dataLabel = data.data_source_label;

  return (
    <article className="animate-msg-assistant w-full rounded-xl border border-white/[0.06] bg-[#080809] p-5">
      <div className="mb-4 flex items-center gap-2.5">
        <BookOpen className="size-4 shrink-0 text-white/70" />
        <div>
          <span className="text-[10px] font-medium uppercase tracking-[0.08em] text-white/22">Visual Lesson Plan</span>
          <p className="text-[15px] font-semibold tracking-[-0.01em] text-white/95">{data.lesson_title || topic}</p>
        </div>
      </div>

      {/* Data source label */}
      {dataLabel && (
        <div className="mb-2 inline-flex items-center gap-1.5 rounded-md border border-white/[0.06] bg-white/[0.03] px-2 py-1">
          <span className="size-1.5 rounded-full bg-emerald-400/60" />
          <span className="text-[10px] text-white/40">{dataLabel}</span>
        </div>
      )}

      <p className="mb-2 text-[11px] text-white/35">{data.syllabus_position}</p>
      <p className="mb-3 text-[12px] text-white/50">{data.learning_goal}</p>

      {/* Stats */}
      <div className="mb-4 flex gap-3">
        <span className="rounded bg-white/[0.04] px-2 py-1 text-[11px] text-white/50">{data.total_frames} frames</span>
        <span className="rounded bg-white/[0.04] px-2 py-1 text-[11px] text-white/50">{Math.round(data.total_estimated_seconds / 60)} min</span>
        <span className="rounded bg-white/[0.04] px-2 py-1 text-[11px] text-white/50">{data.visual_style}</span>
      </div>

      {/* Concept flow */}
      {data.concept_flow?.length > 0 && (
        <div className="mb-4">
          <p className="mb-1.5 text-[10px] font-medium uppercase tracking-[0.08em] text-white/22">Concept Flow</p>
          <div className="flex flex-wrap gap-1.5">
            {data.concept_flow.map((step, i) => (
              <span key={i} className="rounded-md border border-white/[0.06] bg-white/[0.02] px-2 py-1 text-[11px] text-white/50">
                {i + 1}. {step}
              </span>
            ))}
          </div>
        </div>
      )}

      {/* Derivation frames */}
      {data.derivation_frames?.length > 0 && (
        <CollapsibleSection
          title="Derivation Frames"
          icon={<Calculator className="size-3" />}
          expanded={expandedFrames.has("derivation")}
          onToggle={() => toggle("derivation")}
          count={data.derivation_frames.length}
        >
          <div className="space-y-3">
            {data.derivation_frames.map((frame) => (
              <FrameCard key={frame.frame_number} frame={frame} />
            ))}
          </div>
        </CollapsibleSection>
      )}

      {/* Diagram frames */}
      {data.diagram_frames?.length > 0 && (
        <CollapsibleSection
          title="Diagram Frames"
          expanded={expandedFrames.has("diagram")}
          onToggle={() => toggle("diagram")}
          count={data.diagram_frames.length}
        >
          <div className="space-y-3">
            {data.diagram_frames.map((frame) => (
              <FrameCard key={frame.frame_number} frame={frame} />
            ))}
          </div>
        </CollapsibleSection>
      )}

      {/* Numerical frames */}
      {data.numerical_frames?.length > 0 && (
        <CollapsibleSection
          title="Numerical Frames"
          icon={<Calculator className="size-3" />}
          expanded={expandedFrames.has("numerical")}
          onToggle={() => toggle("numerical")}
          count={data.numerical_frames.length}
        >
          <div className="space-y-3">
            {data.numerical_frames.map((frame) => (
              <FrameCard key={frame.frame_number} frame={frame} />
            ))}
          </div>
        </CollapsibleSection>
      )}

      {/* Narration script */}
      {data.narration_script && (
        <div className="mt-3 rounded-lg border border-white/[0.04] bg-white/[0.01] px-3 py-2.5">
          <p className="mb-1 text-[10px] font-medium uppercase tracking-[0.08em] text-white/20">Narration Script</p>
          <p className="text-[12px] leading-[1.6] text-white/50 whitespace-pre-wrap">{data.narration_script.substring(0, 500)}{data.narration_script.length > 500 ? "..." : ""}</p>
        </div>
      )}
    </article>
  );
}

function FrameCard({ frame }: { frame: { frame_number: number; teaching_purpose: string; visual_type: string; on_screen_text: string; narration: string; why_this_helps: string; exam_connection: string; duration_seconds: number; common_misunderstanding_fixed?: string } }) {
  return (
    <div className="rounded-lg border border-white/[0.04] bg-white/[0.01] p-3">
      <div className="flex items-center justify-between gap-2">
        <span className="text-[11px] font-medium text-white/50">Frame {frame.frame_number}</span>
        <span className="rounded bg-white/[0.04] px-1.5 py-0.5 text-[10px] text-white/35">{frame.visual_type}</span>
        <span className="text-[10px] text-white/25">{frame.duration_seconds}s</span>
      </div>
      <p className="mt-1 text-[12px] font-medium text-white/70">{frame.teaching_purpose}</p>
      <p className="mt-1 rounded bg-black/30 px-2 py-1 text-[11px] font-mono text-emerald-400/70 whitespace-pre-wrap">{frame.on_screen_text}</p>
      <p className="mt-1 text-[11px] text-white/45">{frame.narration}</p>
      {frame.common_misunderstanding_fixed && (
        <p className="mt-1 text-[10px] text-amber-400/50">Fixes: {frame.common_misunderstanding_fixed}</p>
      )}
      <p className="mt-1 text-[10px] text-white/50">Exam: {frame.exam_connection}</p>
    </div>
  );
}

function CollapsibleSection({
  title,
  icon,
  expanded,
  onToggle,
  count,
  children,
}: {
  title: string;
  icon?: React.ReactNode;
  expanded: boolean;
  onToggle: () => void;
  count: number;
  children: React.ReactNode;
}) {
  return (
    <div className="mt-3">
      <button
        type="button"
        onClick={onToggle}
        className="flex w-full items-center justify-between gap-2 rounded-lg border border-white/[0.06] bg-white/[0.02] px-3 py-2 transition hover:bg-white/[0.04]"
      >
        <span className="flex items-center gap-1.5 text-[11px] font-medium text-white/50">
          {icon}
          {title}
          <span className="text-[10px] text-white/25">({count})</span>
        </span>
        {expanded ? <ChevronUp className="size-3 text-white/30" /> : <ChevronDown className="size-3 text-white/30" />}
      </button>
      {expanded && <div className="mt-2 pl-1">{children}</div>}
    </div>
  );
}