import { useEffect, useMemo, useState } from 'react';
import ReactECharts from 'echarts-for-react';
import { FontAwesomeIcon } from '@fortawesome/react-fontawesome';
import {
    faUsers, faPhoneVolume, faCalendarCheck, faPhoneMissed,
    faPercent, faTriangleExclamation,
} from '@fortawesome/pro-duotone-svg-icons';
import { TopBar } from '@/components/layout/top-bar';
import { Badge } from '@/components/base/badges/badges';
import { Table } from '@/components/application/table/table';
import { apiClient } from '@/lib/api-client';
import { cx } from '@/utils/cx';

type DateRange = 'today' | 'week' | 'month' | 'year';

const getDateRange = (range: DateRange): { gte: string; lte: string } => {
    const now = new Date();
    const lte = now.toISOString();
    const start = new Date(now);
    if (range === 'today') start.setHours(0, 0, 0, 0);
    else if (range === 'week') { start.setDate(start.getDate() - start.getDay() + 1); start.setHours(0, 0, 0, 0); }
    else if (range === 'month') { start.setDate(1); start.setHours(0, 0, 0, 0); }
    else if (range === 'year') { start.setMonth(0, 1); start.setHours(0, 0, 0, 0); }
    return { gte: start.toISOString(), lte };
};

const parseTime = (timeStr: string): number => {
    if (!timeStr) return 0;
    const parts = timeStr.split(':').map(Number);
    if (parts.length === 3) return parts[0] * 3600 + parts[1] * 60 + parts[2];
    return 0;
};

type AgentPerf = {
    name: string;
    ozonetelagentid: string;
    npsscore: number | null;
    maxidleminutes: number | null;
    minnpsthreshold: number | null;
    minconversionpercent: number | null;
    calls: number;
    inbound: number;
    missed: number;
    followUps: number;
    leads: number;
    appointments: number;
    convPercent: number;
    idleMinutes: number;
    activeMinutes: number;
    wrapMinutes: number;
    breakMinutes: number;
    timeBreakdown: any;
};

const DateFilter = ({ value, onChange }: { value: DateRange; onChange: (v: DateRange) => void }) => (
    <div className="flex rounded-lg border border-secondary overflow-hidden">
        {(['today', 'week', 'month', 'year'] as DateRange[]).map(r => (
            <button key={r} onClick={() => onChange(r)} className={cx(
                'px-3 py-1 text-xs font-medium capitalize transition duration-100 ease-linear',
                value === r ? 'bg-brand-solid text-white' : 'bg-primary text-secondary hover:bg-secondary',
            )}>{r}</button>
        ))}
    </div>
);

const KpiCard = ({ icon, value, label, color }: { icon: any; value: string | number; label: string; color?: string }) => (
    <div className="flex items-center gap-3 rounded-xl border border-secondary bg-primary p-4 min-w-0">
        <div className={cx('flex size-10 items-center justify-center rounded-lg', color ?? 'bg-brand-secondary')}>
            <FontAwesomeIcon icon={icon} className="size-4 text-fg-white" />
        </div>
        <div>
            <p className="text-xl font-bold text-primary">{value}</p>
            <p className="text-xs text-tertiary">{label}</p>
        </div>
    </div>
);

export const TeamPerformancePage = () => {
    const [range, setRange] = useState<DateRange>('week');
    const [agents, setAgents] = useState<AgentPerf[]>([]);
    const [allCalls, setAllCalls] = useState<any[]>([]);
    const [allAppointments, setAllAppointments] = useState<any[]>([]);
    const [loading, setLoading] = useState(true);

    useEffect(() => {
        const load = async () => {
            setLoading(true);
            const { gte, lte } = getDateRange(range);
            const dateStr = new Date().toISOString().split('T')[0];

            try {
                const [callsData, apptsData, leadsData, followUpsData, teamData] = await Promise.all([
                    apiClient.graphql<any>(`{ calls(first: 500, filter: { startedAt: { gte: "${gte}", lte: "${lte}" } }) { edges { node { id direction callStatus agentName startedAt } } } }`, undefined, { silent: true }),
                    apiClient.graphql<any>(`{ appointments(first: 200, filter: { scheduledAt: { gte: "${gte}", lte: "${lte}" } }) { edges { node { id status } } } }`, undefined, { silent: true }),
                    apiClient.graphql<any>(`{ leads(first: 200) { edges { node { id assignedAgent status } } } }`, undefined, { silent: true }),
                    apiClient.graphql<any>(`{ followUps(first: 200) { edges { node { id assignedAgent } } } }`, undefined, { silent: true }),
                    apiClient.get<any>(`/api/supervisor/team-performance?date=${dateStr}`, { silent: true }).catch(() => ({ agents: [] })),
                ]);

                const calls = callsData?.calls?.edges?.map((e: any) => e.node) ?? [];
                const appts = apptsData?.appointments?.edges?.map((e: any) => e.node) ?? [];
                const leads = leadsData?.leads?.edges?.map((e: any) => e.node) ?? [];
                const followUps = followUpsData?.followUps?.edges?.map((e: any) => e.node) ?? [];
                const teamAgents = teamData?.agents ?? [];

                setAllCalls(calls);
                setAllAppointments(appts);

                // Build per-agent metrics
                let agentPerfs: AgentPerf[];

                if (teamAgents.length > 0) {
                    // Real Ozonetel data available
                    agentPerfs = teamAgents.map((agent: any) => {
                        const agentCalls = calls.filter((c: any) => c.agentName === agent.name || c.agentName === agent.ozonetelagentid);
                        const agentLeads = leads.filter((l: any) => l.assignedAgent === agent.name);
                        const agentFollowUps = followUps.filter((f: any) => f.assignedAgent === agent.name);
                        const agentAppts = agentCalls.filter((c: any) => c.callStatus === 'COMPLETED').length;
                        const totalCalls = agentCalls.length;
                        const inbound = agentCalls.filter((c: any) => c.direction === 'INBOUND').length;
                        const missed = agentCalls.filter((c: any) => c.callStatus === 'MISSED').length;

                        const tb = agent.timeBreakdown;
                        const idleSec = tb ? parseTime(tb.totalIdleTime ?? '0:0:0') : 0;
                        const activeSec = tb ? parseTime(tb.totalBusyTime ?? '0:0:0') : 0;
                        const wrapSec = tb ? parseTime(tb.totalWrapupTime ?? '0:0:0') : 0;
                        const breakSec = tb ? parseTime(tb.totalPauseTime ?? '0:0:0') : 0;

                        return {
                            name: agent.name ?? agent.ozonetelagentid,
                            ozonetelagentid: agent.ozonetelagentid,
                            npsscore: agent.npsscore,
                            maxidleminutes: agent.maxidleminutes,
                            minnpsthreshold: agent.minnpsthreshold,
                            minconversionpercent: agent.minconversionpercent,
                            calls: totalCalls,
                            inbound,
                            missed,
                            followUps: agentFollowUps.length,
                            leads: agentLeads.length,
                            appointments: agentAppts,
                            convPercent: totalCalls > 0 ? Math.round((agentAppts / totalCalls) * 100) : 0,
                            idleMinutes: Math.round(idleSec / 60),
                            activeMinutes: Math.round(activeSec / 60),
                            wrapMinutes: Math.round(wrapSec / 60),
                            breakMinutes: Math.round(breakSec / 60),
                            timeBreakdown: tb,
                        };
                    });
                } else {
                    // Fallback: build agent list from call records
                    const agentNames = [...new Set(calls.map((c: any) => c.agentName).filter(Boolean))] as string[];
                    agentPerfs = agentNames.map((name) => {
                        const agentCalls = calls.filter((c: any) => c.agentName === name);
                        const agentLeads = leads.filter((l: any) => l.assignedAgent === name);
                        const agentFollowUps = followUps.filter((f: any) => f.assignedAgent === name);
                        const completed = agentCalls.filter((c: any) => c.callStatus === 'COMPLETED').length;
                        const totalCalls = agentCalls.length;

                        return {
                            name,
                            ozonetelagentid: name,
                            npsscore: null,
                            maxidleminutes: null,
                            minnpsthreshold: null,
                            minconversionpercent: null,
                            calls: totalCalls,
                            inbound: agentCalls.filter((c: any) => c.direction === 'INBOUND').length,
                            missed: agentCalls.filter((c: any) => c.callStatus === 'MISSED').length,
                            followUps: agentFollowUps.length,
                            leads: agentLeads.length,
                            appointments: completed,
                            convPercent: totalCalls > 0 ? Math.round((completed / totalCalls) * 100) : 0,
                            idleMinutes: 0,
                            activeMinutes: 0,
                            wrapMinutes: 0,
                            breakMinutes: 0,
                            timeBreakdown: null,
                        };
                    });
                }

                setAgents(agentPerfs);
            } catch (err) {
                console.error('Failed to load team performance:', err);
            } finally {
                setLoading(false);
            }
        };
        load();
    }, [range]);

    // Aggregate KPIs
    const totalCalls = allCalls.length;
    const totalMissed = allCalls.filter(c => c.callStatus === 'MISSED').length;
    const totalAppts = allAppointments.length;
    const convRate = totalCalls > 0 ? Math.round((totalAppts / totalCalls) * 100) : 0;
    const activeAgents = agents.length;

    // Call trend by day
    const callTrendOption = useMemo(() => {
        const dayMap: Record<string, { inbound: number; outbound: number }> = {};
        for (const c of allCalls) {
            if (!c.startedAt) continue;
            const day = new Date(c.startedAt).toLocaleDateString('en-IN', { weekday: 'short' });
            if (!dayMap[day]) dayMap[day] = { inbound: 0, outbound: 0 };
            if (c.direction === 'INBOUND') dayMap[day].inbound++;
            else dayMap[day].outbound++;
        }
        const days = Object.keys(dayMap);
        return {
            tooltip: { trigger: 'axis' },
            legend: { data: ['Inbound', 'Outbound'], bottom: 0, textStyle: { fontSize: 11 } },
            grid: { top: 10, right: 10, bottom: 50, left: 40 },
            xAxis: { type: 'category', data: days },
            yAxis: { type: 'value' },
            series: [
                { name: 'Inbound', type: 'line', data: days.map(d => dayMap[d].inbound), smooth: true, color: '#2060A0' },
                { name: 'Outbound', type: 'line', data: days.map(d => dayMap[d].outbound), smooth: true, color: '#E88C30' },
            ],
        };
    }, [allCalls]);

    // NPS
    const avgNps = useMemo(() => {
        const withNps = agents.filter(a => a.npsscore != null);
        if (withNps.length === 0) return 0;
        return Math.round(withNps.reduce((sum, a) => sum + (a.npsscore ?? 0), 0) / withNps.length);
    }, [agents]);

    const npsOption = useMemo(() => ({
        tooltip: { trigger: 'item' },
        series: [{
            type: 'gauge', startAngle: 180, endAngle: 0,
            min: 0, max: 100,
            pointer: { show: false },
            progress: { show: true, width: 18, roundCap: true, itemStyle: { color: avgNps >= 70 ? '#22C55E' : avgNps >= 50 ? '#F59E0B' : '#EF4444' } },
            axisLine: { lineStyle: { width: 18, color: [[1, '#E5E7EB']] } },
            axisTick: { show: false }, splitLine: { show: false }, axisLabel: { show: false },
            detail: { valueAnimation: true, fontSize: 28, fontWeight: 'bold', offsetCenter: [0, '-10%'], formatter: '{value}' },
            data: [{ value: avgNps }],
        }],
    }), [avgNps]);

    // Performance alerts
    const alerts = useMemo(() => {
        const list: { agent: string; type: string; value: string; severity: 'error' | 'warning' }[] = [];
        for (const a of agents) {
            if (a.maxidleminutes && a.idleMinutes > a.maxidleminutes) {
                list.push({ agent: a.name, type: 'Excessive Idle Time', value: `${a.idleMinutes}m`, severity: 'error' });
            }
            if (a.minnpsthreshold && (a.npsscore ?? 100) < a.minnpsthreshold) {
                list.push({ agent: a.name, type: 'Low NPS', value: String(a.npsscore ?? 0), severity: 'warning' });
            }
            if (a.minconversionpercent && a.convPercent < a.minconversionpercent) {
                list.push({ agent: a.name, type: 'Low Conversion', value: `${a.convPercent}%`, severity: 'warning' });
            }
        }
        return list;
    }, [agents]);

    // Team time averages
    const teamAvg = useMemo(() => {
        if (agents.length === 0) return { active: 0, wrap: 0, idle: 0, break_: 0 };
        return {
            active: Math.round(agents.reduce((s, a) => s + a.activeMinutes, 0) / agents.length),
            wrap: Math.round(agents.reduce((s, a) => s + a.wrapMinutes, 0) / agents.length),
            idle: Math.round(agents.reduce((s, a) => s + a.idleMinutes, 0) / agents.length),
            break_: Math.round(agents.reduce((s, a) => s + a.breakMinutes, 0) / agents.length),
        };
    }, [agents]);

    if (loading) {
        return (
            <>
                <TopBar title="Team Performance" />
                <div className="flex flex-1 items-center justify-center">
                    <p className="text-sm text-tertiary">Loading team performance...</p>
                </div>
            </>
        );
    }

    return (
        <>
            <TopBar title="Team Performance" subtitle="Aggregated metrics across all agents" />

            <div className="flex flex-1 flex-col overflow-y-auto">
                {/* Section 1: Key Metrics */}
                <div className="px-6 pt-5">
                    <div className="flex items-center justify-between mb-4">
                        <h3 className="text-sm font-semibold text-secondary">Key Metrics</h3>
                        <DateFilter value={range} onChange={setRange} />
                    </div>
                    <div className="grid grid-cols-5 gap-3">
                        <KpiCard icon={faUsers} value={activeAgents} label="Active Agents" color="bg-brand-secondary" />
                        <KpiCard icon={faPhoneVolume} value={totalCalls} label="Total Calls" color="bg-brand-solid" />
                        <KpiCard icon={faCalendarCheck} value={totalAppts} label="Appointments" color="bg-success-solid" />
                        <KpiCard icon={faPhoneMissed} value={totalMissed} label="Missed Calls" color="bg-error-solid" />
                        <KpiCard icon={faPercent} value={`${convRate}%`} label="Conversion Rate" color="bg-warning-solid" />
                    </div>
                </div>

                {/* Section 2: Call Breakdown Trends */}
                <div className="px-6 pt-6">
                    <div className="rounded-xl border border-secondary bg-primary p-4">
                        <h3 className="text-sm font-semibold text-secondary mb-3">Call Breakdown Trends</h3>
                        <div className="flex gap-4">
                            <div className="flex-1">
                                <p className="text-xs text-tertiary mb-2">Inbound vs Outbound</p>
                                <ReactECharts option={callTrendOption} style={{ height: 200 }} />
                            </div>
                        </div>
                    </div>
                </div>

                {/* Section 3: Agent Performance Table */}
                <div className="px-6 pt-6">
                    <div className="rounded-xl border border-secondary bg-primary p-4">
                        <h3 className="text-sm font-semibold text-secondary mb-3">Agent Performance</h3>
                        <Table size="sm">
                            <Table.Header>
                                <Table.Head label="Agent" isRowHeader />
                                <Table.Head label="Calls" className="w-16" />
                                <Table.Head label="Inbound" className="w-20" />
                                <Table.Head label="Missed" className="w-16" />
                                <Table.Head label="Follow-ups" className="w-24" />
                                <Table.Head label="Leads" className="w-16" />
                                <Table.Head label="Conv%" className="w-16" />
                                <Table.Head label="NPS" className="w-16" />
                                <Table.Head label="Idle" className="w-16" />
                            </Table.Header>
                            <Table.Body items={agents}>
                                {(agent) => (
                                    <Table.Row id={agent.ozonetelagentid || agent.name}>
                                        <Table.Cell><span className="text-sm font-medium text-primary">{agent.name}</span></Table.Cell>
                                        <Table.Cell><span className="text-sm text-primary">{agent.calls}</span></Table.Cell>
                                        <Table.Cell><span className="text-sm text-primary">{agent.inbound}</span></Table.Cell>
                                        <Table.Cell><span className="text-sm text-primary">{agent.missed}</span></Table.Cell>
                                        <Table.Cell><span className="text-sm text-primary">{agent.followUps}</span></Table.Cell>
                                        <Table.Cell><span className="text-sm text-primary">{agent.leads}</span></Table.Cell>
                                        <Table.Cell>
                                            <span className={cx('text-sm font-medium', agent.convPercent >= 25 ? 'text-success-primary' : 'text-error-primary')}>
                                                {agent.convPercent}%
                                            </span>
                                        </Table.Cell>
                                        <Table.Cell>
                                            <span className={cx('text-sm font-bold', (agent.npsscore ?? 0) >= 70 ? 'text-success-primary' : (agent.npsscore ?? 0) >= 50 ? 'text-warning-primary' : 'text-error-primary')}>
                                                {agent.npsscore ?? '—'}
                                            </span>
                                        </Table.Cell>
                                        <Table.Cell>
                                            <span className={cx('text-sm', agent.maxidleminutes && agent.idleMinutes > agent.maxidleminutes ? 'text-error-primary font-bold' : 'text-primary')}>
                                                {agent.idleMinutes}m
                                            </span>
                                        </Table.Cell>
                                    </Table.Row>
                                )}
                            </Table.Body>
                        </Table>
                    </div>
                </div>

                {/* Section 4: Time Breakdown */}
                <div className="px-6 pt-6">
                    <div className="rounded-xl border border-secondary bg-primary p-4">
                        <h3 className="text-sm font-semibold text-secondary mb-3">Time Breakdown</h3>
                        {teamAvg.active === 0 && teamAvg.idle === 0 && teamAvg.wrap === 0 && teamAvg.break_ === 0 && (
                            <p className="text-xs text-tertiary mb-3">Time utilisation data unavailable — requires Ozonetel agent session data.</p>
                        )}
                        <div className="flex gap-6 mb-4 px-2">
                            <div className="flex items-center gap-2">
                                <div className="size-3 rounded-sm bg-success-solid" />
                                <span className="text-xs text-secondary">{teamAvg.active}m Active</span>
                            </div>
                            <div className="flex items-center gap-2">
                                <div className="size-3 rounded-sm bg-brand-solid" />
                                <span className="text-xs text-secondary">{teamAvg.wrap}m Wrap</span>
                            </div>
                            <div className="flex items-center gap-2">
                                <div className="size-3 rounded-sm bg-warning-solid" />
                                <span className="text-xs text-secondary">{teamAvg.idle}m Idle</span>
                            </div>
                            <div className="flex items-center gap-2">
                                <div className="size-3 rounded-sm bg-tertiary" />
                                <span className="text-xs text-secondary">{teamAvg.break_}m Break</span>
                            </div>
                        </div>
                        <div className="grid grid-cols-2 lg:grid-cols-3 gap-3">
                            {agents.map(agent => {
                                const total = agent.activeMinutes + agent.wrapMinutes + agent.idleMinutes + agent.breakMinutes || 1;
                                const isHighIdle = agent.maxidleminutes && agent.idleMinutes > agent.maxidleminutes;
                                return (
                                    <div key={agent.name} className={cx('rounded-lg border p-3', isHighIdle ? 'border-error bg-error-secondary' : 'border-secondary')}>
                                        <p className="text-xs font-semibold text-primary mb-2">{agent.name}</p>
                                        <div className="flex h-3 rounded-full overflow-hidden">
                                            <div className="bg-success-solid" style={{ width: `${(agent.activeMinutes / total) * 100}%` }} />
                                            <div className="bg-brand-solid" style={{ width: `${(agent.wrapMinutes / total) * 100}%` }} />
                                            <div className="bg-warning-solid" style={{ width: `${(agent.idleMinutes / total) * 100}%` }} />
                                            <div className="bg-tertiary" style={{ width: `${(agent.breakMinutes / total) * 100}%` }} />
                                        </div>
                                        <div className="flex gap-2 mt-1.5 text-[10px] text-quaternary">
                                            <span>Active {agent.activeMinutes}m</span>
                                            <span>Wrap {agent.wrapMinutes}m</span>
                                            <span>Idle {agent.idleMinutes}m</span>
                                            <span>Break {agent.breakMinutes}m</span>
                                        </div>
                                    </div>
                                );
                            })}
                        </div>
                    </div>
                </div>

                {/* Section 5: NPS + Conversion */}
                <div className="px-6 pt-6">
                    <div className="flex gap-4">
                        <div className="flex-1 rounded-xl border border-secondary bg-primary p-4">
                            <h3 className="text-sm font-semibold text-secondary mb-2">Overall NPS</h3>
                            {agents.every(a => a.npsscore == null) ? (
                                <div className="flex items-center justify-center py-8">
                                    <p className="text-xs text-tertiary">NPS data unavailable — configure NPS scores on agent profiles.</p>
                                </div>
                            ) : (
                            <>
                            <ReactECharts option={npsOption} style={{ height: 150 }} />
                            <div className="space-y-1 mt-2">
                                {agents.filter(a => a.npsscore != null).map(a => (
                                    <div key={a.name} className="flex items-center gap-2">
                                        <span className="text-xs text-secondary w-28 truncate">{a.name}</span>
                                        <div className="flex-1 h-2 rounded-full bg-tertiary overflow-hidden">
                                            <div className={cx('h-full rounded-full', (a.npsscore ?? 0) >= 70 ? 'bg-success-solid' : (a.npsscore ?? 0) >= 50 ? 'bg-warning-solid' : 'bg-error-solid')} style={{ width: `${a.npsscore ?? 0}%` }} />
                                        </div>
                                        <span className="text-xs font-bold text-primary w-8 text-right">{a.npsscore}</span>
                                    </div>
                                ))}
                            </div>
                            </>
                            )}
                        </div>
                        <div className="flex-1 rounded-xl border border-secondary bg-primary p-4">
                            <h3 className="text-sm font-semibold text-secondary mb-3">Conversion Metrics</h3>
                            <div className="flex gap-3 mb-4">
                                <div className="flex-1 rounded-lg bg-secondary p-4 text-center">
                                    <p className="text-2xl font-bold text-brand-secondary">{convRate}%</p>
                                    <p className="text-xs text-tertiary">Call → Appointment</p>
                                </div>
                                <div className="flex-1 rounded-lg bg-secondary p-4 text-center">
                                    <p className="text-2xl font-bold text-brand-secondary">
                                        {agents.length > 0 ? Math.round(agents.reduce((s, a) => s + (a.leads > 0 ? 1 : 0), 0) / agents.length * 100) : 0}%
                                    </p>
                                    <p className="text-xs text-tertiary">Lead → Contact</p>
                                </div>
                            </div>
                            <div className="space-y-1">
                                {agents.map(a => (
                                    <div key={a.name} className="flex items-center gap-2 text-xs">
                                        <span className="text-secondary w-28 truncate">{a.name}</span>
                                        <Badge size="sm" color={a.convPercent >= 25 ? 'success' : 'error'}>{a.convPercent}%</Badge>
                                    </div>
                                ))}
                            </div>
                        </div>
                    </div>
                </div>

                {/* Section 6: Performance Alerts */}
                {alerts.length > 0 && (
                    <div className="px-6 pt-6 pb-8">
                        <div className="rounded-xl border border-secondary bg-primary p-4">
                            <h3 className="text-sm font-semibold text-error-primary mb-3">
                                <FontAwesomeIcon icon={faTriangleExclamation} className="size-3.5 mr-1.5" />
                                Performance Alerts ({alerts.length})
                            </h3>
                            <div className="space-y-2">
                                {alerts.map((alert, i) => (
                                    <div key={i} className={cx(
                                        'flex items-center justify-between rounded-lg px-4 py-3',
                                        alert.severity === 'error' ? 'bg-error-secondary' : 'bg-warning-secondary',
                                    )}>
                                        <div className="flex items-center gap-2">
                                            <FontAwesomeIcon icon={faTriangleExclamation} className={cx('size-3.5', alert.severity === 'error' ? 'text-fg-error-primary' : 'text-fg-warning-primary')} />
                                            <span className="text-sm font-medium text-primary">{alert.agent}</span>
                                            <span className="text-sm text-secondary">— {alert.type}</span>
                                        </div>
                                        <Badge size="sm" color={alert.severity}>{alert.value}</Badge>
                                    </div>
                                ))}
                            </div>
                        </div>
                    </div>
                )}
            </div>
        </>
    );
};