import React, { useState } from 'react';
import { Project, Award, Milestone, Activity, Evidence } from '../../services/api/models';
import { encodeHashIdSync } from '../../services/toolsService';
import { BorderGlow } from '../common/BorderGlow';
import { EvidenceUploadModal } from './EvidenceUploadModal';
import { 
  FolderKanban, 
  ChevronDown, 
  ChevronUp, 
  Calendar, 
  Landmark, 
  Award as AwardIcon, 
  Layers, 
  CheckCircle2, 
  Clock, 
  FileText, 
  UploadCloud, 
  ExternalLink,
  ShieldCheck,
  AlertCircle
} from 'lucide-react';

interface ProjectCardProps {
  project: Project;
  awards: Award[];
  milestones: Milestone[];
  activities: Activity[];
  evidenceList: Evidence[];
  onEvidenceUploaded: () => void;
}

export const ProjectCard: React.FC<ProjectCardProps> = ({
  project,
  awards,
  milestones,
  activities,
  evidenceList,
  onEvidenceUploaded,
}) => {
  const [isExpanded, setIsExpanded] = useState(false);
  const [activeTab, setActiveTab] = useState<'milestones' | 'awards'>('milestones');
  
  // Evidence upload state
  const [uploadTarget, setUploadTarget] = useState<{
    activity: Activity;
    milestone?: Milestone;
  } | null>(null);

  const hashedProjectId = encodeHashIdSync(project.id);

  // Group activities and evidence by milestone
  const getActivitiesForMilestone = (milestoneId?: string | number) => {
    if (!milestoneId) return activities.filter((a) => !a.milestoneId);
    return activities.filter((a) => String(a.milestoneId) === String(milestoneId));
  };

  const getEvidenceForActivity = (activityId?: string | number) => {
    if (!activityId) return [];
    return evidenceList.filter((e) => String(e.activityId) === String(activityId));
  };

  const getEvidenceForMilestone = (milestoneId?: string | number) => {
    if (!milestoneId) return [];
    return evidenceList.filter((e) => String(e.milestoneId) === String(milestoneId));
  };

  // Helper to check if an activity has >= 1 evidence file
  const isActivityDoneWithEvidence = (activityId?: string | number) => {
    const ev = getEvidenceForActivity(activityId);
    return ev.length > 0;
  };

  // Helper to format currency
  const formatCurrency = (amount?: number | string | null) => {
    if (amount === undefined || amount === null || amount === '') return 'R 0.00';
    const num = typeof amount === 'number' ? amount : parseFloat(String(amount));
    if (isNaN(num)) return 'R 0.00';
    return `R ${num.toLocaleString('en-ZA', { minimumFractionDigits: 2, maximumFractionDigits: 2 })}`;
  };

  // Helper for status badge rendering
  const renderStatusBadge = (status?: any, fallback = 'Active') => {
    const str = String(status || fallback).toLowerCase();
    if (str.includes('approved') || str.includes('executed') || str === '2' || str === 'active' || str === 'completed') {
      return (
        <span className="inline-flex items-center gap-1 px-2.5 py-0.5 rounded-full text-[11px] font-semibold bg-emerald-950/80 border border-emerald-500/30 text-emerald-300">
          <CheckCircle2 className="w-3 h-3 text-emerald-400" />
          <span>{status === 2 || status === '2' ? 'Approved' : String(status || fallback)}</span>
        </span>
      );
    }
    if (str.includes('review') || str.includes('pending') || str === '1') {
      return (
        <span className="inline-flex items-center gap-1 px-2.5 py-0.5 rounded-full text-[11px] font-semibold bg-amber-950/80 border border-amber-500/30 text-amber-300">
          <Clock className="w-3 h-3 text-amber-400" />
          <span>{status === 1 || status === '1' ? 'Pending Approval' : String(status || fallback)}</span>
        </span>
      );
    }
    return (
      <span className="inline-flex items-center gap-1 px-2.5 py-0.5 rounded-full text-[11px] font-semibold bg-slate-800/80 border border-slate-700 text-slate-300">
        <span>{String(status || fallback)}</span>
      </span>
    );
  };

  // Calculate project progress across all milestones and activities
  const totalActivities = activities.length;
  const completedActivitiesCount = activities.filter((a) => isActivityDoneWithEvidence(a.id)).length;
  const progressPercent = totalActivities > 0 ? Math.round((completedActivitiesCount / totalActivities) * 100) : (milestones.length > 0 ? 0 : 100);

  const totalAwardsAmount = awards.reduce((sum, a) => sum + (Number(a.amount) || 0), 0);

  return (
    <div className="w-full">
      <BorderGlow
        edgeSensitivity={30}
        glowColor="160 85 70"
        backgroundColor="#090f20"
        borderRadius={24}
        glowRadius={36}
        glowIntensity={1.0}
        coneSpread={26}
        colors={['#10b981', '#14b8a6', '#06b6d4']}
        fillOpacity={0.2}
        className="w-full transition-all backdrop-blur-xl shadow-2xl"
      >
        <div className="p-6 sm:p-7 flex flex-col space-y-6">
          {/* Card Top Header */}
          <div className="flex flex-col md:flex-row md:items-center justify-between gap-4 pb-4 border-b border-white/10">
            <div className="space-y-1.5 flex-1">
              <div className="flex items-center gap-2.5 flex-wrap">
                <div className="p-2 rounded-xl bg-emerald-500/10 border border-emerald-500/20 text-emerald-400 shadow-inner">
                  <FolderKanban className="w-4 h-4" />
                </div>
                {hashedProjectId && (
                  <span className="font-mono text-xs font-bold text-emerald-300 bg-emerald-950/70 border border-emerald-500/30 px-2 py-0.5 rounded-md shadow-sm">
                    #{hashedProjectId}
                  </span>
                )}
                {project.code && (
                  <span className="font-mono text-xs text-slate-300 bg-white/5 border border-white/10 px-2 py-0.5 rounded-md">
                    {project.code}
                  </span>
                )}
                {renderStatusBadge(project.status, 'In Progress')}
              </div>

              <h3 className="text-xl font-extrabold tracking-tight text-white mt-1">
                {project.name || `Project #${hashedProjectId}`}
              </h3>

              {project.description && (
                <p className="text-xs text-slate-300 line-clamp-2 leading-relaxed max-w-3xl">
                  {project.description}
                </p>
              )}
            </div>

            {/* Key Stats Pill */}
            <div className="flex items-center gap-3 shrink-0 flex-wrap sm:flex-nowrap">
              <div className="bg-slate-950/60 border border-white/10 px-4 py-2 rounded-2xl">
                <div className="text-[10px] text-slate-400 uppercase tracking-wider font-semibold">Total Budget</div>
                <div className="text-sm font-bold text-emerald-300 font-mono">
                  {formatCurrency(project.budget || totalAwardsAmount)}
                </div>
              </div>

              <div className="bg-slate-950/60 border border-white/10 px-4 py-2 rounded-2xl">
                <div className="text-[10px] text-slate-400 uppercase tracking-wider font-semibold">Linked Awards</div>
                <div className="text-sm font-bold text-cyan-300 font-mono">
                  {awards.length} Award{awards.length !== 1 ? 's' : ''}
                </div>
              </div>
            </div>
          </div>

          {/* Meta Bar: Dates & Milestone Progress */}
          <div className="grid grid-cols-1 sm:grid-cols-3 gap-4 text-xs">
            {/* Timeline */}
            <div className="flex items-center gap-2 text-slate-300">
              <Calendar className="w-4 h-4 text-slate-400 shrink-0" />
              <div>
                <span className="text-slate-500 block text-[10px] uppercase font-bold">Timeline</span>
                <span>
                  {project.startedAt ? new Date(project.startedAt).toLocaleDateString() : 'Start Pending'} —{' '}
                  {project.endedAt ? new Date(project.endedAt).toLocaleDateString() : 'Open'}
                </span>
              </div>
            </div>

            {/* Milestones & Activities count */}
            <div className="flex items-center gap-2 text-slate-300">
              <Layers className="w-4 h-4 text-teal-400 shrink-0" />
              <div>
                <span className="text-slate-500 block text-[10px] uppercase font-bold">Deliverables</span>
                <span>
                  {milestones.length} Milestone{milestones.length !== 1 ? 's' : ''} • {totalActivities} Activit{totalActivities !== 1 ? 'ies' : 'y'}
                </span>
              </div>
            </div>

            {/* Evidence Verification Progress */}
            <div className="space-y-1 sm:text-right">
              <div className="flex items-center sm:justify-end gap-2 text-[11px]">
                <span className="text-slate-400">Evidence Completion:</span>
                <span className="font-mono font-bold text-emerald-300">{progressPercent}%</span>
              </div>
              <div className="w-full bg-slate-950/80 rounded-full h-2 overflow-hidden border border-white/5">
                <div
                  className="bg-gradient-to-r from-emerald-500 to-teal-400 h-full rounded-full transition-all duration-500"
                  style={{ width: `${progressPercent}%` }}
                />
              </div>
            </div>
          </div>

          {/* Expand / Collapse Button */}
          <div className="pt-2 flex justify-between items-center border-t border-white/5">
            <div className="flex items-center gap-2">
              <button
                onClick={() => {
                  setIsExpanded(true);
                  setActiveTab('milestones');
                }}
                className={`px-3 py-1.5 rounded-xl text-xs font-semibold transition-all cursor-pointer ${
                  isExpanded && activeTab === 'milestones'
                    ? 'bg-emerald-500/20 text-emerald-300 border border-emerald-500/30'
                    : 'text-slate-400 hover:text-slate-200 bg-white/[0.02] hover:bg-white/[0.06] border border-white/10'
                }`}
              >
                Milestones & Activities ({milestones.length})
              </button>
              <button
                onClick={() => {
                  setIsExpanded(true);
                  setActiveTab('awards');
                }}
                className={`px-3 py-1.5 rounded-xl text-xs font-semibold transition-all cursor-pointer ${
                  isExpanded && activeTab === 'awards'
                    ? 'bg-cyan-500/20 text-cyan-300 border border-cyan-500/30'
                    : 'text-slate-400 hover:text-slate-200 bg-white/[0.02] hover:bg-white/[0.06] border border-white/10'
                }`}
              >
                Historic & Current Awards ({awards.length})
              </button>
            </div>

            <button
              onClick={() => setIsExpanded(!isExpanded)}
              className="flex items-center gap-1.5 px-3.5 py-1.5 rounded-xl bg-white/[0.04] hover:bg-white/[0.08] border border-white/10 text-xs font-semibold text-slate-300 hover:text-white transition-all cursor-pointer shadow-sm"
            >
              <span>{isExpanded ? 'Collapse Details' : 'Expand Project Details'}</span>
              {isExpanded ? <ChevronUp className="w-3.5 h-3.5" /> : <ChevronDown className="w-3.5 h-3.5" />}
            </button>
          </div>

          {/* Expanded Section */}
          {isExpanded && (
            <div className="pt-4 border-t border-white/10 animate-in fade-in slide-in-from-top-2 duration-300 space-y-6">
              {/* TAB 1: MILESTONES & ACTIVITIES */}
              {activeTab === 'milestones' && (
                <div className="space-y-4">
                  <div className="flex items-center justify-between">
                    <div>
                      <h4 className="text-sm font-bold text-white flex items-center gap-2">
                        <Layers className="w-4 h-4 text-emerald-400" />
                        Milestone Deliverables & Activity Verification
                      </h4>
                      <p className="text-[11px] text-slate-400 mt-0.5">
                        Upload 1 or more evidence files against each activity. A milestone is verified when all its activities have evidence.
                      </p>
                    </div>
                  </div>

                  {milestones.length === 0 ? (
                    <div className="p-6 rounded-2xl bg-slate-950/40 border border-white/5 text-center text-xs text-slate-400">
                      No milestones recorded for this project yet.
                    </div>
                  ) : (
                    <div className="space-y-4">
                      {milestones.map((milestone) => {
                        const milestoneActs = getActivitiesForMilestone(milestone.id);
                        const milestoneEvidence = getEvidenceForMilestone(milestone.id);
                        const actsWithEvidence = milestoneActs.filter((a) => isActivityDoneWithEvidence(a.id));
                        const isMilestoneFullyEvidenced = milestoneActs.length > 0 && actsWithEvidence.length === milestoneActs.length;

                        return (
                          <div
                            key={milestone.id}
                            className="rounded-2xl border border-white/10 bg-slate-950/60 p-4 sm:p-5 space-y-3 shadow-inner"
                          >
                            {/* Milestone Header */}
                            <div className="flex flex-col sm:flex-row sm:items-center justify-between gap-2 pb-2.5 border-b border-white/5">
                              <div className="space-y-1">
                                <div className="flex items-center gap-2 flex-wrap">
                                  <span className="font-mono text-xs text-emerald-300 font-bold">
                                    Milestone #{encodeHashIdSync(milestone.id)}
                                  </span>
                                  {renderStatusBadge(milestone.status, 'In Progress')}
                                  {isMilestoneFullyEvidenced && (
                                    <span className="inline-flex items-center gap-1 px-2 py-0.5 rounded-full text-[10px] font-bold bg-emerald-500/20 text-emerald-300 border border-emerald-500/40">
                                      <ShieldCheck className="w-3 h-3" />
                                      Evidence Complete
                                    </span>
                                  )}
                                </div>
                                <h5 className="text-sm font-bold text-slate-100">{milestone.name || 'Milestone Target'}</h5>
                              </div>

                              <div className="text-xs text-slate-400 flex items-center gap-4">
                                {milestone.dueAt && (
                                  <span>
                                    Due: <span className="text-slate-200 font-mono">{new Date(milestone.dueAt).toLocaleDateString()}</span>
                                  </span>
                                )}
                                <span className="font-mono text-[11px] text-teal-300 bg-teal-950/60 border border-teal-500/20 px-2 py-0.5 rounded-md">
                                  {actsWithEvidence.length} / {milestoneActs.length} Activities Verified
                                </span>
                              </div>
                            </div>

                            {/* Nested Activities */}
                            <div className="space-y-2 pt-1">
                              <div className="text-[11px] font-semibold uppercase tracking-wider text-slate-400">
                                Activities & Uploaded Evidence
                              </div>

                              {milestoneActs.length === 0 ? (
                                <div className="py-2 text-xs text-slate-500 italic">
                                  No individual activities defined under this milestone.
                                </div>
                              ) : (
                                <div className="space-y-2.5">
                                  {milestoneActs.map((act) => {
                                    const actEvidence = getEvidenceForActivity(act.id);
                                    const isDone = actEvidence.length > 0;

                                    return (
                                      <div
                                        key={act.id}
                                        className="p-3.5 rounded-xl bg-white/[0.02] border border-white/5 hover:border-white/10 transition-colors space-y-2.5"
                                      >
                                        <div className="flex flex-col sm:flex-row sm:items-center justify-between gap-2">
                                          <div className="space-y-1">
                                            <div className="flex items-center gap-2">
                                              <span className="font-semibold text-xs text-slate-200">
                                                {act.title || `Activity #${encodeHashIdSync(act.id)}`}
                                              </span>
                                              {isDone ? (
                                                <span className="inline-flex items-center gap-1 px-2 py-0.5 rounded-md text-[10px] font-bold bg-emerald-950/80 border border-emerald-500/30 text-emerald-300">
                                                  <CheckCircle2 className="w-3 h-3 text-emerald-400" />
                                                  Done ({actEvidence.length} Evidence)
                                                </span>
                                              ) : (
                                                <span className="inline-flex items-center gap-1 px-2 py-0.5 rounded-md text-[10px] font-medium bg-amber-950/60 border border-amber-500/20 text-amber-300">
                                                  <Clock className="w-3 h-3 text-amber-400" />
                                                  Pending Evidence
                                                </span>
                                              )}
                                            </div>

                                            {act.description && (
                                              <p className="text-[11px] text-slate-400">{act.description}</p>
                                            )}
                                          </div>

                                          {/* Upload Evidence Button */}
                                          <button
                                            onClick={() => setUploadTarget({ activity: act, milestone })}
                                            className="inline-flex items-center gap-1.5 px-3 py-1.5 rounded-xl bg-emerald-500/10 hover:bg-emerald-500/20 border border-emerald-500/30 text-emerald-300 hover:text-emerald-200 text-xs font-semibold transition-all shrink-0 cursor-pointer shadow-sm hover:shadow-[0_0_12px_rgba(16,185,129,0.2)]"
                                          >
                                            <UploadCloud className="w-3.5 h-3.5" />
                                            <span>Upload Evidence</span>
                                          </button>
                                        </div>

                                        {/* List of uploaded evidence records against this activity */}
                                        {actEvidence.length > 0 && (
                                          <div className="pt-2 border-t border-white/5 space-y-1.5">
                                            <div className="text-[10px] uppercase font-bold tracking-wider text-slate-500">
                                              Attached Deliverables ({actEvidence.length}):
                                            </div>
                                            <div className="grid grid-cols-1 sm:grid-cols-2 gap-2">
                                              {actEvidence.map((ev) => (
                                                <div
                                                  key={ev.id}
                                                  className="flex items-center justify-between p-2 rounded-lg bg-slate-900/80 border border-white/5 text-[11px]"
                                                >
                                                  <div className="flex items-center gap-2 truncate">
                                                    <FileText className="w-3.5 h-3.5 text-emerald-400 shrink-0" />
                                                    <span className="text-slate-200 font-medium truncate">
                                                      {ev.title || ev.fileName || `Evidence #${encodeHashIdSync(ev.id)}`}
                                                    </span>
                                                  </div>
                                                  {ev.documentUrl && (
                                                    <a
                                                      href={ev.documentUrl}
                                                      target="_blank"
                                                      rel="noreferrer"
                                                      className="text-emerald-400 hover:text-emerald-300 p-1 hover:bg-white/5 rounded shrink-0"
                                                      title="View Document"
                                                    >
                                                      <ExternalLink className="w-3 h-3" />
                                                    </a>
                                                  )}
                                                </div>
                                              ))}
                                            </div>
                                          </div>
                                        )}
                                      </div>
                                    );
                                  })}
                                </div>
                              )}
                            </div>
                          </div>
                        );
                      })}
                    </div>
                  )}
                </div>
              )}

              {/* TAB 2: AWARDS */}
              {activeTab === 'awards' && (
                <div className="space-y-4">
                  <div className="flex items-center justify-between">
                    <div>
                      <h4 className="text-sm font-bold text-white flex items-center gap-2">
                        <AwardIcon className="w-4 h-4 text-cyan-400" />
                        Grantee Awards (Historic & Current)
                      </h4>
                      <p className="text-[11px] text-slate-400 mt-0.5">
                        Official grant award commitments linked to this project portfolio.
                      </p>
                    </div>
                  </div>

                  {awards.length === 0 ? (
                    <div className="p-6 rounded-2xl bg-slate-950/40 border border-white/5 text-center text-xs text-slate-400">
                      No grant awards linked to this project.
                    </div>
                  ) : (
                    <div className="grid grid-cols-1 md:grid-cols-2 gap-3">
                      {awards.map((award) => (
                        <div
                          key={award.id}
                          className="p-4 rounded-2xl bg-slate-950/60 border border-white/10 space-y-2.5 shadow-inner"
                        >
                          <div className="flex items-center justify-between">
                            <span className="font-mono text-xs font-bold text-cyan-300">
                              Award #{encodeHashIdSync(award.id)}
                            </span>
                            {renderStatusBadge(award.status, 'Active')}
                          </div>

                          <div className="space-y-1">
                            <div className="text-[10px] text-slate-400 uppercase font-semibold">Award Amount</div>
                            <div className="text-lg font-bold text-white font-mono">
                              {formatCurrency(award.amount)}
                            </div>
                          </div>

                          <div className="pt-2 border-t border-white/5 flex items-center justify-between text-[11px] text-slate-400">
                            <span>
                              Created: <span className="text-slate-300">{award.createdAt ? new Date(award.createdAt).toLocaleDateString() : 'N/A'}</span>
                            </span>
                            {award.programmeId && (
                              <span className="font-mono text-[10px] text-slate-400">
                                Prog #{encodeHashIdSync(award.programmeId)}
                              </span>
                            )}
                          </div>
                        </div>
                      ))}
                    </div>
                  )}
                </div>
              )}
            </div>
          )}
        </div>
      </BorderGlow>

      {/* Modal for Evidence Upload */}
      {uploadTarget && (
        <EvidenceUploadModal
          isOpen={true}
          onClose={() => setUploadTarget(null)}
          project={project}
          milestone={uploadTarget.milestone}
          activity={uploadTarget.activity}
          onEvidenceUploaded={() => {
            onEvidenceUploaded();
            setUploadTarget(null);
          }}
        />
      )}
    </div>
  );
};