import { useState, useRef, useEffect } from 'react';
import { useSetupData, SetupData } from "@/context/SetupDataContext";
import EditIcon from '@mui/icons-material/Edit';
import AddIcon from '@mui/icons-material/Add';
import RefreshIcon from '@mui/icons-material/Refresh';
import CancelIcon from '@mui/icons-material/Cancel';
import { List, Card, CardContent, Typography, Box, useTheme, useMediaQuery, CircularProgress, IconButton } from '@mui/material';
import { DataGrid, GridColDef, GridRenderCellParams, GridRowModel, GridToolbarContainer, GridToolbarQuickFilter, GridToolbarExport, GridToolbarDensitySelector, GridToolbarColumnsButton } from '@mui/x-data-grid';
import Mailing from '@/types/mailing';
//import Template from '@/types/template';
import MailingEdit from "@/components/modals/MailingEdit";
import ConfirmationDialog from "@/components/modals/ConfirmationDialog";
import { useCustomFetch } from "@/utils/customFetch";

function NewMailings() {
    const customFetch = useCustomFetch();
    const theme = useTheme();
    const setupData: SetupData = useSetupData();
    const isMobile = useMediaQuery(theme.breakpoints.down("sm"));

    const gridContainerRef = useRef<HTMLDivElement | null>(null);
    const [mailingsLoading, setMailingsLoading] = useState<boolean>(false);
    const [mailings, setMailings] = useState<Mailing[]>([]);
    const [selectedRow, setSelectedRow] = useState<Mailing | null>(null);
    const [open, setOpen] = useState<boolean>(false);
    const [confirmDialogOpen, setConfirmDialogOpen] = useState<boolean>(false);
    const [mailingToCancel, setMailingToCancel] = useState<Mailing | null>(null);

    const columns: GridColDef<Mailing>[] = [
        {
            field: "actions",
            headerName: "",
            sortable: false,
            width: 100,
            renderCell: (params: GridRenderCellParams<Mailing>) => (
                <>
                    <IconButton color="primary" onClick={(e) => { e.stopPropagation(); handleEdit(params.row); }}>
                        <EditIcon />
                    </IconButton>
                    <IconButton color="secondary" onClick={(e) => { e.stopPropagation(); handleCancelClick(params.row); }}>
                        <CancelIcon />
                    </IconButton>
                </>
            ),
        },
        { field: "id", headerName: "ID", width: 80 },
        { field: "name", headerName: "Name", flex: 1, minWidth: 160 },
        { field: "description", headerName: "Description", flex: 1, minWidth: 200 },
        {
            field: "templateId",
            headerName: "Subject",
            flex: 1,
            minWidth: 160,
            valueGetter: (_: number, row: Mailing) => setupData.templates.find(t => t.id === row.templateId)?.subject || 'Unknown',
        },
    ];

    const reloadMailings = async () => {
        setMailingsLoading(true);

        const mailingsResponse = await customFetch("/api/mailings/status/ed");
        const mailingsData = await mailingsResponse.json();
        if (mailingsData) {
            setMailings(mailingsData);
            setMailingsLoading(false);
        }
        else {
            console.error("Failed to fetch mailings");
            setMailingsLoading(false);
        }
    }

    const handleNew = () => {
        setSelectedRow(null);
        setOpen(true);
    };

    const handleEdit = (row: GridRowModel<Mailing>) => {
        setSelectedRow(row);
        setOpen(true);
    };

    const handleUpdateRow = (updatedRow: Mailing) => {
        if (updatedRow.statusCode.toUpperCase() !== "ED")
            removeMailing(updatedRow);
        else
            updateMailings(updatedRow);
    };

    const handleCancelClick = (row: Mailing) => {
        setMailingToCancel(row);
        setConfirmDialogOpen(true);
    };

    const handleCancelConfirm = async () => {
        if (!mailingToCancel) return;

        try {
            const response = await customFetch(`/api/mailings/${mailingToCancel.id}/cancel`, { method: 'POST' });
            if (response.ok) {
                setMailings((prev) => prev.filter(m => m.id !== mailingToCancel.id));
            } else {
                console.error("Failed to cancel mailing");
            }
        } catch (error) {
            console.error("Error cancelling mailing:", error);
        } finally {
            setConfirmDialogOpen(false);
            setMailingToCancel(null);
        }
    };

    const handleCancelDialogClose = () => {
        setConfirmDialogOpen(false);
        setMailingToCancel(null);
    };

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

    const removeMailing = (mailing: Mailing) => {
        setMailings((prevMailings) => {
            return prevMailings.filter(el => el.id !== mailing.id);
        });
    }
    const updateMailings = (updatedMailing: Mailing) => {
        setMailings((prev) => {
            const exists = prev.some((e) => e.id === updatedMailing.id);

            return exists
                ? prev.map((server) => (server.id === updatedMailing.id ? updatedMailing : server))
                : [...prev, updatedMailing];
        });
    };
    return (
        <Box ref={gridContainerRef} sx={{
            position: 'relative', left: 0, right: 0, height: "calc(100vh - 124px)", overflow: "hidden",
            transition: theme.transitions.create(['width', 'height'], {
                easing: theme.transitions.easing.easeInOut,
                duration: theme.transitions.duration.standard,
            })
        }}>
            <Box sx={{ position: 'absolute', inset: 0 }}>
                {isMobile ? (
                    <List>
                        {mailings.map((row) => (
                            <Card key={row.id} sx={{ marginBottom: 2 }}>
                                <Box sx={{ display: 'flex', justifyContent: 'space-between', alignItems: 'center' }}>
                                    <CardContent>
                                        <Typography variant="h6">{row.name}</Typography>
                                        <Typography variant="body2">ID: {row.id}</Typography>
                                        <Typography variant="body2">Description: {row.description}</Typography>
                                        <Typography variant="body2">Subject: {setupData.templates.find(t => t.id === row.templateId)?.subject || 'Unknown'}</Typography>
                                    </CardContent>
                                    <IconButton onClick={(e) => { e.stopPropagation(); handleEdit(row); }}>
                                        <EditIcon />
                                    </IconButton>
                                    <IconButton color="secondary" onClick={() => handleCancelClick(row)}>
                                        <CancelIcon />
                                    </IconButton>
                                </Box>
                            </Card>
                        ))}
                    </List>
                ) : (
                    <DataGrid
                        rows={mailings}
                        columns={columns}
                        autoPageSize
                        sx={{ minWidth: "600px" }}
                        slots={{
                            toolbar: () => (
                                <GridToolbarContainer sx={{ display: "flex", alignItems: "center" }}>
                                    <IconButton size="small" color="primary" onClick={handleNew} sx={{ marginLeft: 1 }}>
                                        <AddIcon />
                                    </IconButton>
                                    <IconButton size="small" color="primary" onClick={() => reloadMailings()} sx={{ marginLeft: 1 }}>
                                        {mailingsLoading ? <CircularProgress size={24} color="inherit" /> : <RefreshIcon />}
                                    </IconButton>
                                    <GridToolbarColumnsButton />
                                    <GridToolbarDensitySelector />
                                    <GridToolbarExport />
                                    <GridToolbarQuickFilter sx={{ ml: "auto" }} />
                                </GridToolbarContainer>
                            ),
                        }}
                        slotProps={{
                            toolbar: {
                                showQuickFilter: true,
                            },
                        }}
                        initialState={{
                            pagination: {
                                paginationModel: {
                                    pageSize: 20,
                                },
                            },
                            sorting: {
                                sortModel: [{ field: 'id', sort: 'asc' }], 
                            },
                        }}
                        pageSizeOptions={[10, 20, 50, 100]}
                    />
                )}
            </Box>

            {open && (
                <MailingEdit
                    open={open}
                    mailing={selectedRow}
                    onClose={(reason) => { if (reason !== 'backdropClick') setOpen(false) }}
                    onSave={handleUpdateRow}
                />
            )}
            {confirmDialogOpen && (
                <ConfirmationDialog
                    open={confirmDialogOpen}
                    title="Cancel Mailing"
                    message={`Are you sure you want to cancel the mailing "${mailingToCancel?.name}"? This action cannot be undone.`}
                    onConfirm={handleCancelConfirm}
                    onCancel={handleCancelDialogClose}
                />
            )}
        </Box>
    );
}

export default NewMailings;