import { IconDatabase } from "@tabler/icons-react";
import { useState } from "react";
import { Badge, Button, Card, Col, Container, Nav, Row, Table } from "react-bootstrap";
import CodeEditor from "@uiw/react-textarea-code-editor";
import { useQuery } from "@tanstack/react-query";
import { executeQuery, getTables, getTableData } from "src/api/backend";
import { HasPermission, Loading } from "src/components";
import { showError, showSuccess } from "src/notifications";
import { ADMIN, VIEW } from "src/modules/Permissions";

export default function DatabaseManager() {
	const [activeTab, setActiveTab] = useState<"tables" | "query">("tables");
	const [activeTable, setActiveTable] = useState<string | null>(null);
	const [query, setQuery] = useState("SELECT * FROM user LIMIT 10;");
	const [queryResult, setQueryResult] = useState<any>(null);
	const [queryLoading, setQueryLoading] = useState(false);

	const { data: tables, isLoading: tablesLoading } = useQuery({
		queryKey: ["database-tables"],
		queryFn: getTables,
	});

	const { data: tableData, isLoading: tableDataLoading } = useQuery({
		queryKey: ["database-table", activeTable, 0, 50],
		queryFn: () => getTableData(activeTable as string, 0, 50),
		enabled: !!activeTable && activeTab === "tables",
	});

	// Select the first table by default when tables are loaded
	if (tables && tables.length > 0 && !activeTable) {
		setActiveTable(tables[0]);
	}

	const handleExecuteQuery = async () => {
		try {
			setQueryLoading(true);
			const res = await executeQuery(query);
			setQueryResult(res.result);
			showSuccess("Query executed successfully");
		} catch (err: any) {
			showError(err.message || "Failed to execute query");
		} finally {
			setQueryLoading(false);
		}
	};

	const renderTableData = (data: any[], schema?: any[]) => {
		if (!data || data.length === 0) return <div className="text-muted p-3">No data</div>;
		
		const columns = schema ? schema.map((s: any) => s.name || s.Field) : Object.keys(data[0]);

		return (
			<div className="table-responsive">
				<Table striped bordered hover size="sm" className="mb-0 text-nowrap">
					<thead>
						<tr>
							{columns.map((col: string) => (
								<th key={col}>{col}</th>
							))}
						</tr>
					</thead>
					<tbody>
						{data.map((row: any, i: number) => (
							<tr key={i}>
								{columns.map((col: string) => (
									<td key={`${i}-${col}`}>
										{row[col] === null ? (
											<span className="text-muted">NULL</span>
										) : typeof row[col] === "object" ? (
											JSON.stringify(row[col])
										) : (
											String(row[col])
										)}
									</td>
								))}
							</tr>
						))}
					</tbody>
				</Table>
			</div>
		);
	};

	return (
		<HasPermission section={ADMIN} permission={VIEW}>
			<Container className="my-4" fluid>
				<div className="d-flex align-items-center mb-4">
					<IconDatabase size={28} className="me-2 text-primary" />
					<h2 className="mb-0">Database Manager</h2>
					<Badge bg="danger" className="ms-3 rounded-pill text-uppercase" style={{ letterSpacing: "1px" }}>
						Super Admin Only
					</Badge>
				</div>

				<Nav variant="pills" className="mb-4">
					<Nav.Item>
						<Nav.Link 
							active={activeTab === "tables"} 
							onClick={() => setActiveTab("tables")}
							className="rounded-pill px-4"
							style={{ cursor: "pointer" }}
						>
							Data Viewer
						</Nav.Link>
					</Nav.Item>
					<Nav.Item>
						<Nav.Link 
							active={activeTab === "query"} 
							onClick={() => setActiveTab("query")}
							className="rounded-pill px-4"
							style={{ cursor: "pointer" }}
						>
							SQL Editor
						</Nav.Link>
					</Nav.Item>
				</Nav>

				{activeTab === "tables" && (
					<Row>
						<Col md={3}>
							<Card className="shadow-sm">
								<Card.Header className="bg-light fw-bold">Tables</Card.Header>
								<div className="list-group list-group-flush" style={{ maxHeight: "70vh", overflowY: "auto" }}>
									{tablesLoading && <div className="p-3"><Loading /></div>}
									{tables?.map((table: string) => (
										<button
											key={table}
											className={`list-group-item list-group-item-action ${activeTable === table ? "active" : ""}`}
											onClick={() => setActiveTable(table)}
										>
											{table}
										</button>
									))}
								</div>
							</Card>
						</Col>
						<Col md={9}>
							<Card className="shadow-sm">
								<Card.Header className="bg-light d-flex justify-content-between align-items-center">
									<h5 className="mb-0 fw-bold">{activeTable || "Select a table"}</h5>
									{tableData && <Badge bg="secondary">{tableData.total} rows</Badge>}
								</Card.Header>
								<Card.Body className="p-0" style={{ maxHeight: "70vh", overflowY: "auto" }}>
									{tableDataLoading ? (
										<div className="p-5 d-flex justify-content-center"><Loading /></div>
									) : (
										tableData && renderTableData(tableData.rows, tableData.schema)
									)}
								</Card.Body>
							</Card>
						</Col>
					</Row>
				)}

				{activeTab === "query" && (
					<Card className="shadow-sm">
						<Card.Header className="bg-light fw-bold">Execute SQL Query</Card.Header>
						<Card.Body>
							<div className="mb-3 border rounded">
								<CodeEditor
									value={query}
									language="sql"
									placeholder="Please enter SQL code."
									onChange={(ev) => setQuery(ev.target.value)}
									padding={15}
									style={{
										fontSize: 14,
										backgroundColor: "#f8f9fa",
										fontFamily: "ui-monospace,SFMono-Regular,SF Mono,Consolas,Liberation Mono,Menlo,monospace",
										minHeight: "200px"
									}}
								/>
							</div>
							<div className="d-flex justify-content-end mb-4">
								<Button 
									variant="primary" 
									onClick={handleExecuteQuery} 
									disabled={queryLoading || !query.trim()}
								>
									{queryLoading ? <span className="me-2"><Loading /></span> : null}
									Execute Query
								</Button>
							</div>

							{queryResult && (
								<div className="mt-4">
									<h5 className="mb-3 border-bottom pb-2">Results</h5>
									{Array.isArray(queryResult) ? renderTableData(queryResult) : (
										<pre className="p-3 bg-light rounded border">
											{JSON.stringify(queryResult, null, 2)}
										</pre>
									)}
								</div>
							)}
						</Card.Body>
					</Card>
				)}
			</Container>
		</HasPermission>
	);
}