import React, { useState } from "react";
import { base44 } from "@/api/base44Client";
import { useQuery } from "@tanstack/react-query";
import { Link, useNavigate } from "react-router-dom";
import { createPageUrl } from "@/utils";
import { Button } from "@/components/ui/button";
import { Card, CardHeader, CardTitle, CardContent } from "@/components/ui/card";
import { Users, Building2, UserPlus, TrendingUp, MapPin, Calendar, DollarSign, Award, Target, BarChart3, Shield, Leaf } from "lucide-react";
import StatsCard from "../components/staff/StatsCard";
import EcosystemWheel from "../components/dashboard/EcosystemWheel";
import QuickMetrics from "../components/dashboard/QuickMetrics";
import PageHeader from "../components/common/PageHeader";

export default function Dashboard() {
  const navigate = useNavigate();
  const [selectedLayer, setSelectedLayer] = useState(null);

  const { data: staff, isLoading: loadingStaff } = useQuery({
    queryKey: ['staff'],
    queryFn: () => base44.entities.Staff.list('-created_date'),
    initialData: [],
  });

  const { data: events, isLoading: loadingEvents } = useQuery({
    queryKey: ['events'],
    queryFn: () => base44.entities.Event.list('-date'),
    initialData: [],
  });

  const recentStaff = staff.slice(0, 6);
  const uniqueDepartments = [...new Set(staff.map(s => s.department).filter(Boolean))];
  const uniqueLocations = [...new Set(staff.map(s => s.hub_location).filter(Boolean))];
  
  // Calculate key metrics
  const totalFillRate = 97;
  const totalSpend = 2.3;
  const overallScore = "A+";
  const activeEvents = events.filter(e => e.status === "Active" || e.status === "Confirmed").length;
  const completionRate = events.length > 0 ? Math.round((events.filter(e => e.status === "Completed").length / events.length) * 100) : 0;

  const ecosystemLayers = [
    {
      name: "Buyer(Procurements)",
      icon: DollarSign,
      color: "from-[#0A39DF] to-[#1C323E]",
      metrics: { fillRate: "97%", spend: "$2.3M", score: "A+" },
      route: "ProcurementDashboard"
    },
    {
      name: "Enterprises (Operator)",
      icon: Target,
      color: "from-emerald-500 to-emerald-700",
      metrics: { coverage: "94%", incidents: "2", satisfaction: "4.8/5" },
      route: "OperatorDashboard"
    },
    {
      name: "Sectors (Execution)",
      icon: Building2,
      color: "from-purple-500 to-purple-700",
      metrics: { active: activeEvents, revenue: "$1.8M", growth: "+12%" },
      route: "OperatorDashboard"
    },
    {
      name: "Partner",
      icon: Users,
      color: "from-pink-500 to-pink-700",
      metrics: { total: "45", retention: "92%", nps: "8.5" },
      route: "Business"
    },
    {
      name: "Approved Vendor",
      icon: Award,
      color: "from-amber-500 to-amber-700",
      metrics: { partners: "12", rating: "4.7/5", compliance: "98%" },
      route: "VendorDashboard"
    },
    {
      name: "Workforce",
      icon: UserPlus,
      color: "from-[#0A39DF] to-[#0A39DF]/80",
      metrics: { total: staff.length, active: staff.filter(s => s.check_in).length, trained: "89%" },
      route: "WorkforceDashboard"
    }
  ];

  return (
    <div className="p-4 md:p-8 bg-gradient-to-br from-slate-50 to-slate-100 min-h-screen">
      <div className="max-w-7xl mx-auto">
        <PageHeader 
          title="Welcome to KROW"
          subtitle="Your Complete Workforce Management Ecosystem"
          actions={
            <>
              <Button variant="outline" className="border-slate-300 hover:bg-slate-100">
                <BarChart3 className="w-4 h-4 mr-2" />
                Reports
              </Button>
              <Link to={createPageUrl("Events")}>
                <Button className="bg-gradient-to-r from-[#0A39DF] to-[#1C323E] hover:from-[#0A39DF]/90 hover:to-[#1C323E]/90 text-white shadow-lg">
                  <Calendar className="w-5 h-5 mr-2" />
                  View All Events
                </Button>
              </Link>
            </>
          }
        />

        {/* Global Metrics */}
        <div className="grid grid-cols-1 md:grid-cols-4 gap-6 mb-8">
          <StatsCard
            title="Fill Rate"
            value={`${totalFillRate}%`}
            icon={Target}
            gradient="bg-gradient-to-br from-[#0A39DF] to-[#1C323E]"
            change="+2.5% this month"
          />
          <StatsCard
            title="Total Spend"
            value={`$${totalSpend}M`}
            icon={DollarSign}
            gradient="bg-gradient-to-br from-emerald-500 to-emerald-700"
            change="+$180K this month"
          />
          <StatsCard
            title="Overall Score"
            value={overallScore}
            icon={Award}
            gradient="bg-gradient-to-br from-amber-500 to-amber-600"
          />
          <StatsCard
            title="Active Events"
            value={activeEvents}
            icon={Calendar}
            gradient="bg-gradient-to-br from-purple-500 to-purple-700"
            change={`${completionRate}% completion rate`}
          />
        </div>

        {/* Ecosystem Puzzle */}
        <Card className="mb-8 border-slate-200 shadow-xl overflow-hidden">
          <CardHeader className="bg-gradient-to-br from-slate-50 to-white border-b border-slate-100">
            <CardTitle className="text-[#1C323E] flex items-center gap-2">
              <Target className="w-6 h-6 text-[#0A39DF]" />
              Ecosystem Connection Map
            </CardTitle>
            <p className="text-sm text-slate-500 mt-1">Interactive puzzle showing how each layer connects • Hover to see metrics • Click to explore</p>
          </CardHeader>
          <CardContent className="p-8">
            <EcosystemWheel 
              layers={ecosystemLayers}
              onLayerClick={(layer) => navigate(createPageUrl(layer.route))}
              selectedLayer={selectedLayer}
              onLayerHover={setSelectedLayer}
            />
          </CardContent>
        </Card>

        {/* Quick Access Cards */}
        <div className="grid grid-cols-1 md:grid-cols-3 gap-6 mb-8">
          <QuickMetrics
            title="Procurement & Vendor Intelligence"
            description="Vendor efficiency, spend analysis, compliance tracking"
            icon={Shield}
            metrics={[
              { label: "Vendor Score", value: "A+", color: "text-green-600" },
              { label: "Compliance", value: "98%", color: "text-blue-600" },
              { label: "ESG Rating", value: "B+", color: "text-emerald-600" }
            ]}
            route="ProcurementDashboard"
            gradient="from-[#0A39DF]/10 to-[#1C323E]/10"
          />

          <QuickMetrics
            title="Operator & Sector Dashboard"
            description="Live coverage, demand forecast, incident tracking"
            icon={MapPin}
            metrics={[
              { label: "Coverage", value: "94%", color: "text-green-600" },
              { label: "Incidents", value: "2", color: "text-yellow-600" },
              { label: "Forecast Accuracy", value: "91%", color: "text-blue-600" }
            ]}
            route="OperatorDashboard"
            gradient="from-emerald-500/10 to-emerald-700/10"
          />

          <QuickMetrics
            title="Vendor Dashboard"
            description="Orders, invoices, workforce pulse, KROW score"
            icon={Award}
            metrics={[
              { label: "Fill Rate", value: "97%", color: "text-green-600" },
              { label: "Attendance", value: "95%", color: "text-blue-600" },
              { label: "Training", value: "92%", color: "text-purple-600" }
            ]}
            route="VendorDashboard"
            gradient="from-amber-500/10 to-amber-700/10"
          />
        </div>

        {/* Workforce Section */}
        <Card className="border-slate-200 shadow-lg">
          <CardHeader className="bg-gradient-to-br from-slate-50 to-white border-b border-slate-100">
            <div className="flex items-center justify-between">
              <div>
                <CardTitle className="text-[#1C323E] flex items-center gap-2">
                  <Users className="w-6 h-6 text-[#0A39DF]" />
                  Workforce Overview
                </CardTitle>
                <p className="text-sm text-slate-500 mt-1">Recent additions and active workers</p>
              </div>
              <div className="flex gap-2">
                <Link to={createPageUrl("WorkforceDashboard")}>
                  <Button variant="outline" className="border-slate-300">
                    View Workforce App
                  </Button>
                </Link>
                <Link to={createPageUrl("StaffDirectory")}>
                  <Button className="bg-[#0A39DF] hover:bg-[#0A39DF]/90">
                    View All Staff
                  </Button>
                </Link>
              </div>
            </div>
          </CardHeader>
          <CardContent className="p-6">
            <div className="grid grid-cols-1 md:grid-cols-3 gap-4">
              {recentStaff.slice(0, 3).map((member) => (
                <div key={member.id} className="p-4 rounded-lg border border-slate-200 hover:border-[#0A39DF] hover:shadow-md transition-all">
                  <div className="flex items-center gap-3 mb-3">
                    <div className="w-12 h-12 bg-gradient-to-br from-[#0A39DF] to-[#1C323E] rounded-xl flex items-center justify-center text-white font-bold">
                      {member.initial || member.employee_name?.charAt(0)}
                    </div>
                    <div>
                      <h4 className="font-semibold text-[#1C323E]">{member.employee_name}</h4>
                      <p className="text-sm text-slate-500">{member.position}</p>
                    </div>
                  </div>
                  <div className="space-y-2 text-sm">
                    <div className="flex justify-between">
                      <span className="text-slate-500">Rating:</span>
                      <span className="font-semibold">{member.rating || 0}/5 ⭐</span>
                    </div>
                    <div className="flex justify-between">
                      <span className="text-slate-500">Coverage:</span>
                      <span className="font-semibold text-green-600">{member.shift_coverage_percentage || 0}%</span>
                    </div>
                    <div className="flex justify-between">
                      <span className="text-slate-500">Cancellations:</span>
                      <span className="font-semibold text-red-600">{member.cancellation_count || 0}</span>
                    </div>
                  </div>
                </div>
              ))}
            </div>
          </CardContent>
        </Card>
      </div>
    </div>
  );
}