"use client";

import { useMemo } from "react";
import type { CoursePlanResult } from "./learnAnythingTypes";

interface CoursePlanCardProps {
  coursePlan: CoursePlanResult;
}

/**
 * Display the backend-generated course plan.
 * Must show all available fields from CoursePlanResult.
 * Must respect truth rules: no fake claims, honest source labels.
 */
export function CoursePlanCard({ coursePlan }: CoursePlanCardProps) {
  const hasUploadedSource = coursePlan.data_source_label === "Uploaded source";
  const contextItems = [
    ["Class", coursePlan.student_context.class_level],
    ["Syllabus", coursePlan.student_context.syllabus],
    ["Subject", coursePlan.student_context.subject],
    ["Chapter", coursePlan.student_context.chapter],
    ["Exam", coursePlan.student_context.exam_date],
    ["Daily time", coursePlan.student_context.daily_study_time],
    ["Goal", coursePlan.student_context.goal],
  ].filter(([, value]) => value);

  // Format duration
  const formatDuration = (minutes: number) => {
    if (minutes < 60) return `${minutes} min`;
    const hours = Math.floor(minutes / 60);
    const remainingMinutes = minutes % 60;
    if (remainingMinutes === 0) return hours === 1 ? "1 hour" : `${hours} hours`;
    return hours === 1 ? `1 hour ${remainingMinutes} min` : `${hours} hours ${remainingMinutes} min`;
  };

  // Format course type label
  const courseTypeLabel = useMemo(() => {
    if (coursePlan.source_basis === "source_upload") return "Source-backed course";
    if (coursePlan.source_basis === "catalog_seed") return "Catalog-based course";
    if (coursePlan.source_basis === "syllabus") return "Syllabus-based course";
    return "Starter course plan";
  }, [coursePlan.source_basis]);

  return (
    <div className="w-full rounded-2xl border border-white/15 bg-white/[0.03] overflow-hidden">
      {/* Header */}
      <div className="border-b border-white/10 p-6">
        <div className="flex items-start justify-between gap-4">
          <div className="flex-1">
            <div className="flex items-center gap-3 mb-2">
              <h2 className="text-xl font-semibold text-white line-clamp-2">{coursePlan.title}</h2>
              {/* Source Badge */}
              <span className={`text-xs font-medium px-2 py-0.5 rounded-full ${
                hasUploadedSource
                  ? "bg-green-500/10 text-green-400 border border-green-500/20"
                  : "bg-white/10 text-white/40 border border-white/15"
              }`}>
                {coursePlan.data_source_label}
              </span>
            </div>

            <div className="flex flex-wrap items-center gap-4 text-sm">
              <span className="text-white/70">
                Level: <span className="text-white">{coursePlan.learner_level || "General"}</span>
              </span>
              <span className="text-white/70">
                Subject: <span className="text-white">{coursePlan.subject_area || "General"}</span>
              </span>
              <span className="text-white/70">
                Total: <span className="text-white">{coursePlan.lessons_total} lessons</span> / {formatDuration(coursePlan.estimated_total_minutes)}
              </span>
              {coursePlan.estimated_study_time && (
                <span className="text-white/70">
                  Study time: <span className="text-white">{coursePlan.estimated_study_time}</span>
                </span>
              )}
            </div>

            {/* Trust Notes - always visible if present */}
            {coursePlan.trust_notes && coursePlan.trust_notes.length > 0 && (
              <div className="mt-4 flex flex-wrap gap-2">
                {coursePlan.trust_notes.map((note, index) => (
                  <span
                    key={index}
                    className="text-xs text-white/50 bg-white/5 px-2 py-1 rounded-lg border border-white/10"
                  >
                    {note}
                  </span>
                ))}
              </div>
            )}
          </div>
        </div>
      </div>

      {/* Main Content */}
      <div className="p-6 space-y-6">
        {/* Confidence */}
        {coursePlan.confidence > 0 && (
          <div className="flex items-center gap-2 text-sm">
            <span className="text-white/60">Confidence:</span>
            <div className="flex items-center gap-1">
              <div className="w-20 h-2 bg-white/10 rounded-full overflow-hidden">
                <div
                  className="h-full bg-white/30 rounded-full transition-all"
                  style={{ width: `${Math.min(coursePlan.confidence * 100, 100)}%` }}
                />
              </div>
              <span className="text-white/70 text-xs">{(coursePlan.confidence * 100).toFixed(0)}%</span>
            </div>
          </div>
        )}

        {contextItems.length > 0 && (
          <section>
            <h3 className="text-sm font-medium text-white/70 mb-2 uppercase tracking-wider">
              Student Context
            </h3>
            <div className="grid grid-cols-1 sm:grid-cols-2 gap-2">
              {contextItems.map(([label, value]) => (
                <div key={label} className="rounded-lg border border-white/10 bg-white/[0.02] px-3 py-2">
                  <p className="text-[11px] uppercase tracking-wider text-white/35">{label}</p>
                  <p className="text-sm text-white/80">{value}</p>
                </div>
              ))}
            </div>
          </section>
        )}

        {coursePlan.lesson_outline.length > 0 && (
          <section>
            <h3 className="text-sm font-medium text-white/70 mb-2 uppercase tracking-wider">
              Lesson Outline
            </h3>
            <div className="space-y-2">
              {coursePlan.lesson_outline.map((item, index) => (
                <div key={`${item}-${index}`} className="flex items-start gap-3 rounded-lg border border-white/10 bg-white/[0.02] p-3">
                  <span className="mt-0.5 flex h-6 w-6 shrink-0 items-center justify-center rounded-full border border-white/15 text-xs text-white/50">
                    {index + 1}
                  </span>
                  <p className="text-sm text-white/78">{item}</p>
                </div>
              ))}
            </div>
          </section>
        )}

        {coursePlan.prerequisite_check.length > 0 && (
          <section>
            <h3 className="text-sm font-medium text-white/70 mb-2 uppercase tracking-wider">
              Prerequisite Check
            </h3>
            <ul className="space-y-2">
              {coursePlan.prerequisite_check.map((item, index) => (
                <li key={`${item}-${index}`} className="rounded-lg border border-white/10 bg-white/[0.02] px-3 py-2 text-sm text-white/78">
                  {item}
                </li>
              ))}
            </ul>
          </section>
        )}

        {coursePlan.concept_explanation && (
          <section>
            <h3 className="text-sm font-medium text-white/70 mb-2 uppercase tracking-wider">
              Concept Explanation
            </h3>
            <div className="rounded-xl border border-white/10 bg-white/[0.02] p-4">
              <p className="text-base font-semibold text-white">{coursePlan.concept_explanation.title}</p>
              <p className="mt-2 text-sm leading-6 text-white/78">{coursePlan.concept_explanation.explanation}</p>
              {coursePlan.concept_explanation.board_exam_focus && (
                <p className="mt-3 rounded-lg bg-white/[0.04] px-3 py-2 text-xs leading-5 text-white/60">
                  {coursePlan.concept_explanation.board_exam_focus}
                </p>
              )}
            </div>
          </section>
        )}

        {coursePlan.derivation_or_problem_steps.length > 0 && (
          <section>
            <h3 className="text-sm font-medium text-white/70 mb-2 uppercase tracking-wider">
              Derivation / Problem Steps
            </h3>
            <div className="space-y-3">
              {coursePlan.derivation_or_problem_steps.map((item) => (
                <div key={item.title} className="rounded-xl border border-white/10 bg-white/[0.02] p-4">
                  <p className="text-sm font-semibold text-white">{item.title}</p>
                  <ol className="mt-3 space-y-2">
                    {item.steps.map((step, index) => (
                      <li key={step} className="flex gap-3 text-sm text-white/78">
                        <span className="text-white/35">{index + 1}.</span>
                        <span>{step}</span>
                      </li>
                    ))}
                  </ol>
                  {item.common_mistake && (
                    <p className="mt-3 text-xs text-white/45">Common mark loss: {item.common_mistake}</p>
                  )}
                </div>
              ))}
            </div>
          </section>
        )}

        {/* Prerequisites */}
        {coursePlan.prerequisites && coursePlan.prerequisites.length > 0 && (
          <section>
            <h3 className="text-sm font-medium text-white/70 mb-2 uppercase tracking-wider">
              Prerequisites
            </h3>
            <div className="flex flex-wrap gap-2">
              {coursePlan.prerequisites.map((prereq, index) => (
                <span
                  key={index}
                  className="text-sm text-white/80 bg-white/5 px-3 py-1 rounded-lg border border-white/10"
                >
                  {prereq}
                </span>
              ))}
            </div>
          </section>
        )}

        {/* Final Outcome */}
        {coursePlan.final_outcome && (
          <section>
            <h3 className="text-sm font-medium text-white/70 mb-2 uppercase tracking-wider">
              Final Outcome
            </h3>
            <p className="text-sm text-white/80">{coursePlan.final_outcome}</p>
          </section>
        )}

        {/* Next Action */}
        {coursePlan.next_action && (
          <section>
            <h3 className="text-sm font-medium text-white/70 mb-2 uppercase tracking-wider">
              Next Action
            </h3>
            <p className="text-sm text-white/80">{coursePlan.next_action}</p>
          </section>
        )}

        {/* Key Concepts */}
        {coursePlan.key_concepts && coursePlan.key_concepts.length > 0 && (
          <section>
            <h3 className="text-sm font-medium text-white/70 mb-2 uppercase tracking-wider">
              Key Concepts
            </h3>
            <div className="grid grid-cols-1 sm:grid-cols-2 gap-2">
              {coursePlan.key_concepts.map((concept, index) => (
                <span
                  key={index}
                  className="text-sm text-white/80 bg-white/5 px-3 py-2 rounded-lg border border-white/10"
                >
                  {concept}
                </span>
              ))}
            </div>
          </section>
        )}

        {coursePlan.practice_questions.length > 0 && (
          <QuestionSection title="Practice Questions" questions={coursePlan.practice_questions} />
        )}

        {coursePlan.pyq_style_questions.length > 0 && (
          <QuestionSection title="PYQ-Style Questions" questions={coursePlan.pyq_style_questions} />
        )}

        {coursePlan.weak_topic_repairs.length > 0 && (
          <section>
            <h3 className="text-sm font-medium text-white/70 mb-2 uppercase tracking-wider">
              Weak Topic Repair
            </h3>
            <div className="grid grid-cols-1 sm:grid-cols-2 gap-3">
              {coursePlan.weak_topic_repairs.map((repair) => (
                <div key={repair.topic} className="rounded-lg border border-white/10 bg-white/[0.02] p-3">
                  <p className="text-sm font-medium text-white">{repair.topic}</p>
                  <p className="mt-1 text-xs leading-5 text-white/50">{repair.symptom}</p>
                  <p className="mt-2 text-xs leading-5 text-white/70">{repair.repair_task}</p>
                </div>
              ))}
            </div>
          </section>
        )}

        {coursePlan.revision_plan.length > 0 && (
          <section>
            <h3 className="text-sm font-medium text-white/70 mb-2 uppercase tracking-wider">
              Revision Plan
            </h3>
            <div className="space-y-2">
              {coursePlan.revision_plan.map((item) => (
                <div key={`${item.timing}-${item.task}`} className="rounded-lg border border-white/10 bg-white/[0.02] p-3">
                  <div className="flex flex-wrap items-center justify-between gap-2">
                    <p className="text-sm font-medium text-white">{item.timing}</p>
                    <span className="text-xs text-white/45">{item.estimated_minutes} min</span>
                  </div>
                  <p className="mt-1 text-sm text-white/78">{item.task}</p>
                  <p className="mt-1 text-xs text-white/45">{item.purpose}</p>
                </div>
              ))}
            </div>
          </section>
        )}

        {/* Modules - Main Content */}
        {coursePlan.modules && coursePlan.modules.length > 0 && (
          <section>
            <h3 className="text-sm font-medium text-white mb-2 uppercase tracking-wider">
              Course Modules
            </h3>
            <div className="space-y-4">
              {coursePlan.modules.map((module, moduleIndex) => (
                <div
                  key={moduleIndex}
                  className="rounded-xl border border-white/10 bg-white/[0.02] p-4"
                >
                  <div className="flex items-start gap-3 mb-3">
                    <span className="flex-shrink-0 w-8 h-8 flex items-center justify-center rounded-full border border-white/15 bg-white/[0.05] text-sm text-white/50 font-medium">
                      {moduleIndex + 1}
                    </span>
                    <div className="flex-1">
                      <h4 className="text-lg font-semibold text-white">{module.title}</h4>
                      {module.estimated_minutes > 0 && (
                        <p className="text-sm text-white/50">
                          ~{formatDuration(module.estimated_minutes)}
                        </p>
                      )}
                      <p className="text-xs text-white/40 mt-1">
                        Source: {module.source_basis}
                      </p>
                    </div>
                  </div>

                  {/* Module Lessons */}
                  <div className="space-y-2 ml-11">
                    {module.lessons.map((lesson, lessonIndex) => (
                      <div
                        key={lessonIndex}
                        className="flex items-center gap-3 text-sm"
                      >
                        <span className="w-2 h-2 rounded-full bg-white/20 flex-shrink-0" />
                        <div className="flex-1">
                          <p className="text-white/90">{lesson.title}</p>
                          <p className="text-xs text-white/40 line-clamp-1">{lesson.task}</p>
                        </div>
                        <span className="text-xs text-white/50 flex-shrink-0">
                          {lesson.duration_minutes} min
                        </span>
                      </div>
                    ))}
                  </div>
                </div>
              ))}
            </div>
          </section>
        )}

        {/* Practice Tasks */}
        {coursePlan.practice_tasks && coursePlan.practice_tasks.length > 0 && (
          <section>
            <h3 className="text-sm font-medium text-white/70 mb-2 uppercase tracking-wider">
              Practice Tasks
            </h3>
            <div className="grid grid-cols-1 sm:grid-cols-2 gap-3">
              {coursePlan.practice_tasks.map((task, index) => (
                <div
                  key={index}
                  className="rounded-lg border border-white/10 bg-white/[0.02] p-3"
                >
                  <p className="text-sm font-medium text-white">{task.title}</p>
                  <p className="text-xs text-white/50 mt-1">{task.description || task.task_type}</p>
                  <p className="text-xs text-white/40 mt-1">Type: {task.task_type}</p>
                </div>
              ))}
            </div>
          </section>
        )}

        {/* Quizzes */}
        {coursePlan.quizzes && coursePlan.quizzes.length > 0 && (
          <section>
            <h3 className="text-sm font-medium text-white/70 mb-2 uppercase tracking-wider">
              Quizzes
            </h3>
            <div className="grid grid-cols-1 sm:grid-cols-2 gap-3">
              {coursePlan.quizzes.map((quiz, index) => (
                <div
                  key={index}
                  className="rounded-lg border border-white/10 bg-white/[0.02] p-3"
                >
                  <p className="text-sm font-medium text-white">{quiz.title}</p>
                  <p className="text-xs text-white/50 mt-1">
                    {quiz.question_count} questions
                  </p>
                  {quiz.focus_areas && quiz.focus_areas.length > 0 && (
                    <p className="text-xs text-white/40 mt-1 line-clamp-1">
                      Focus: {quiz.focus_areas.join(", ")}
                    </p>
                  )}
                </div>
              ))}
            </div>
          </section>
        )}

        {/* Revision Checkpoints */}
        {coursePlan.revision_checkpoints && coursePlan.revision_checkpoints.length > 0 && (
          <section>
            <h3 className="text-sm font-medium text-white/70 mb-2 uppercase tracking-wider">
              Revision Checkpoints
            </h3>
            <div className="grid grid-cols-1 sm:grid-cols-2 gap-3">
              {coursePlan.revision_checkpoints.map((checkpoint, index) => (
                <div
                  key={index}
                  className="rounded-lg border border-white/10 bg-white/[0.02] p-3"
                >
                  <p className="text-sm font-medium text-white">{checkpoint.title}</p>
                  <p className="text-xs text-white/50 mt-1">
                    {checkpoint.estimated_minutes} minutes
                  </p>
                  {checkpoint.focus_areas && checkpoint.focus_areas.length > 0 && (
                    <p className="text-xs text-white/40 mt-1 line-clamp-1">
                      Focus: {checkpoint.focus_areas.join(", ")}
                    </p>
                  )}
                </div>
              ))}
            </div>
          </section>
        )}
      </div>

      {/* Footer */}
      <div className="border-t border-white/10 p-4">
        <p className="text-xs text-white/40 text-center">
          Generated by DocDoe AI | {courseTypeLabel}
          {!hasUploadedSource && " | No uploaded source used"}
        </p>
      </div>
    </div>
  );
}

function QuestionSection({
  title,
  questions,
}: {
  title: string;
  questions: CoursePlanResult["practice_questions"];
}) {
  return (
    <section>
      <h3 className="text-sm font-medium text-white/70 mb-2 uppercase tracking-wider">
        {title}
      </h3>
      <div className="grid grid-cols-1 sm:grid-cols-2 gap-3">
        {questions.map((question) => (
          <div key={`${question.question}-${question.marks}`} className="rounded-lg border border-white/10 bg-white/[0.02] p-3">
            <div className="mb-2 flex items-center justify-between gap-2">
              <span className="rounded-full border border-white/10 px-2 py-0.5 text-[11px] text-white/45">
                {question.marks} marks
              </span>
              <span className="text-[11px] uppercase tracking-wider text-white/35">
                {question.question_type.replaceAll("_", " ")}
              </span>
            </div>
            <p className="text-sm font-medium leading-5 text-white">{question.question}</p>
            {question.answer_hint && (
              <p className="mt-2 text-xs leading-5 text-white/50">{question.answer_hint}</p>
            )}
          </div>
        ))}
      </div>
    </section>
  );
}