import { useEffect, useState } from 'react';
import { useNavigate } from 'react-router-dom';
import { Card, CardContent, CardHeader, CardTitle, CardDescription } from "@/components/ui/card";
import { Table, TableBody, TableCell, TableHead, TableHeader, TableRow } from "@/components/ui/table";
import { Badge } from "@/components/ui/badge";
import { Button } from "@/components/ui/button";
import { Loader2, ArrowRight, History, RefreshCw, Trash2 } from "lucide-react";
import { WorkflowHistorySummaryDto } from '@/api/schema.gen';
import { z } from 'zod';
import { client } from '@/api/client';
import { useAnalysisTemplates } from "@/hooks/useConfig";

type WorkflowHistorySummary = z.infer<typeof WorkflowHistorySummaryDto>;

export function RecentWorkflowsList() {
    const [history, setHistory] = useState<WorkflowHistorySummary[]>([]);
    const [loading, setLoading] = useState(false);
    const navigate = useNavigate();
    const { data: templates } = useAnalysisTemplates();

    const fetchHistory = async () => {
        setLoading(true);
        try {
            // Using generated client to fetch history
            const data = await client.get_workflow_histories({ queries: { limit: 5 } });
            setHistory(data);
        } catch (err) {
            console.error("Failed to fetch history:", err);
        } finally {
            setLoading(false);
        }
    };

    const handleClearHistory = async () => {
        if (confirm("Are you sure you want to clear ALL history? This cannot be undone.")) {
            try {
                const res = await fetch('/api/v1/system/history', { method: 'DELETE' });
                if (res.ok) {
                    fetchHistory();
                } else {
                    console.error("Failed to clear history");
                    alert("Failed to clear history");
                }
            } catch (e) {
                console.error(e);
                alert("Error clearing history");
            }
        }
    };

    useEffect(() => {
        fetchHistory();
    }, []);

    if (!loading && history.length === 0) {
        return null;
    }

    return (
        <Card className="w-full max-w-4xl mx-auto shadow-md mt-8">
            <CardHeader className="flex flex-row items-center justify-between pb-2">
                <div className="space-y-1">
                    <CardTitle className="text-xl flex items-center gap-2">
                        <History className="h-5 w-5" />
                        Recent Analysis Reports
                    </CardTitle>
                    <CardDescription>
                        Your recently generated fundamental analysis reports.
                    </CardDescription>
                </div>
                <div className="flex gap-2">
                    <Button variant="ghost" size="icon" onClick={handleClearHistory} title="Clear All History">
                        <Trash2 className="h-4 w-4 text-muted-foreground hover:text-destructive" />
                    </Button>
                    <Button variant="ghost" size="icon" onClick={fetchHistory} disabled={loading}>
                        <RefreshCw className={`h-4 w-4 ${loading ? 'animate-spin' : ''}`} />
                    </Button>
                </div>
            </CardHeader>
            <CardContent>
                <Table>
                    <TableHeader>
                        <TableRow>
                            <TableHead>Symbol</TableHead>
                            <TableHead>Market</TableHead>
                            <TableHead>Template</TableHead>
                            <TableHead>Status</TableHead>
                            <TableHead>Date</TableHead>
                            <TableHead className="text-right">Action</TableHead>
                        </TableRow>
                    </TableHeader>
                    <TableBody>
                        {loading && history.length === 0 ? (
                            <TableRow>
                                <TableCell colSpan={6} className="h-24 text-center">
                                    <Loader2 className="h-6 w-6 animate-spin mx-auto" />
                                </TableCell>
                            </TableRow>
                        ) : (
                            history.map((item) => (
                                <TableRow key={item.request_id} className="group cursor-pointer hover:bg-muted/50" onClick={() => navigate(`/history/${item.request_id}`)}>
                                    <TableCell className="font-medium">{item.symbol}</TableCell>
                                    <TableCell>{item.market}</TableCell>
                                    <TableCell className="text-muted-foreground">{templates?.find(t => t.id === item.template_id)?.name || item.template_id || 'Default'}</TableCell>
                                    <TableCell>
                                        <StatusBadge status={item.status} />
                                    </TableCell>
                                    <TableCell className="text-muted-foreground">
                                        {new Date(item.start_time).toLocaleString()}
                                    </TableCell>
                                    <TableCell className="text-right">
                                        <Button variant="ghost" size="sm" className="opacity-0 group-hover:opacity-100 transition-opacity">
                                            View <ArrowRight className="ml-2 h-4 w-4" />
                                        </Button>
                                    </TableCell>
                                </TableRow>
                            ))
                        )}
                    </TableBody>
                </Table>
            </CardContent>
        </Card>
    );
}

function StatusBadge({ status }: { status: string }) {
    let variant: "default" | "destructive" | "outline" | "secondary" = "outline";
    let className = "";
    
    switch (status.toLowerCase()) {
        case 'completed':
            variant = "default";
            className = "bg-green-600 hover:bg-green-700";
            break;
        case 'failed':
            variant = "destructive";
            break;
        case 'running':
        case 'pending':
            variant = "secondary";
            className = "text-blue-600 bg-blue-100";
            break;
        default:
            variant = "outline";
    }

    return (
        <Badge variant={variant} className={className}>
            {status}
        </Badge>
    );
}