import { useState, useRef, useEffect } from 'react';
import VisibilityIcon from '@mui/icons-material/Visibility';
import ContentCopyIcon from '@mui/icons-material/ContentCopy';
import CancelIcon from '@mui/icons-material/Cancel';
import RefreshIcon from '@mui/icons-material/Refresh';
import { Box, useTheme, useMediaQuery, CircularProgress, IconButton, List, Card, CardContent, Typography } from '@mui/material';
import { DataGrid, GridColDef, GridRenderCellParams, GridToolbarContainer, GridToolbarQuickFilter, GridToolbarExport, GridToolbarDensitySelector, GridToolbarColumnsButton } from '@mui/x-data-grid';
import Mailing from '@/types/mailing';
import MailingEdit from "@/components/modals/MailingEdit";
import MailingView from "@/components/modals/MailingView"; // Assume this is a new read-only view component
import ConfirmationDialog from "@/components/modals/ConfirmationDialog";

function ScheduleMailings() {
    const theme = useTheme();
    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 [viewOpen, setViewOpen] = useState<boolean>(false);
    const [editOpen, setEditOpen] = useState<boolean>(false);
    const [confirmDialogOpen, setConfirmDialogOpen] = useState<boolean>(false); 
    const [mailingToCancel, setMailingToCancel] = useState<Mailing | null>(null);
    const [forceRender, setForceRender] = useState(false);

    const formatRecurringString = (typeCode: string, startDate: string): string => {
        const date = new Date(startDate);
        switch (typeCode.toUpperCase()) {
            case 'D':
                return `Daily at ${date.toLocaleTimeString([], { hour: '2-digit', minute: '2-digit' })}`;
            case 'W':
                return `Weekly on ${date.toLocaleDateString('en-US', { weekday: 'long' })} at ${date.toLocaleTimeString([], { hour: '2-digit', minute: '2-digit' })}`;
            case 'M':
                return `Monthly on day ${date.getDate()} at ${date.toLocaleTimeString([], { hour: '2-digit', minute: '2-digit' })}`;
            default:
                return 'Custom recurring schedule';
        }
    };

    const columns: GridColDef<Mailing>[] = [
        {
            field: "actions",
            headerName: "",
            sortable: false,
            width: 140,
            renderCell: (params: GridRenderCellParams<Mailing>) => (
                <>
                    <IconButton color="primary" onClick={(e) => { e.stopPropagation(); handleView(params.row); }}>
                        <VisibilityIcon />
                    </IconButton>
                    <IconButton color="primary" onClick={(e) => { e.stopPropagation(); handleCopy(params.row); }}>
                        <ContentCopyIcon />
                    </IconButton>
                    <IconButton color="secondary" onClick={(e) => { e.stopPropagation(); handleCancelClick(params.row); }}>
                        <CancelIcon />
                    </IconButton>
                </>
            ),
        },
        { field: "name", headerName: "Name", flex: 1, minWidth: 160 },
        {
            field: "scheduleDate",
            headerName: "Schedule Date",
            flex: 1,
            minWidth: 200,
            valueGetter: (_: any, row: Mailing) => row.scheduleDate ? new Date(row.scheduleDate).toLocaleString() : 'N/A'
        },
        {
            field: "recurring",
            headerName: "Recurring",
            flex: 1,
            minWidth: 200,
            valueGetter: (_: any, mailing: Mailing) => mailing.recurringTypeCode && mailing.recurringStartDate
                ? formatRecurringString(mailing.recurringTypeCode, mailing.recurringStartDate)
                : ''
        },
    ];

    const reloadMailings = async () => {
        setMailingsLoading(true);
        const mailingsResponse = await fetch("/api/mailings/status/sc"); // Adjust endpoint as needed
        const mailingsData = await mailingsResponse.json();
        if (mailingsData) {
            setMailings(mailingsData);
            setMailingsLoading(false);
            setForceRender(true);
        } else {
            console.error("Failed to fetch scheduled mailings");
            setMailingsLoading(false);
        }
    };

    const handleView = (row: Mailing) => {
        setSelectedRow(row);
        setViewOpen(true);
    };

    const handleCopy = (row: Mailing) => {
        const newMailing = { ...row, id: 0 }; // Copy all fields except ID
        setSelectedRow(newMailing);
        setEditOpen(true);
    };

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

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

        try {
            const response = await fetch(`/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);
    };

    const handleUpdateRow = (updatedRow: Mailing) => {
        setMailings((prev) => [...prev, updatedRow]);
    };

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

    useEffect(() => {
        if (forceRender) {
            setForceRender(false);
        }
    }, [forceRender]);

    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 ? (
                    mailingsLoading ? (
                        <Box sx={{ display: 'flex', justifyContent: 'center', alignItems: 'center', height: '100%' }}>
                            <CircularProgress />
                        </Box>
                    ) : (
                <List>
                    {mailings.map((mailing) => (
                        <Card key={mailing.id} sx={{ marginBottom: 2 }}>
                            <Box sx={{ display: 'flex', justifyContent: 'space-between', alignItems: 'center' }}>
                                <CardContent>
                                    <Typography variant="h6">{mailing.name}</Typography>
                                    <Typography variant="body2">
                                        Schedule Date: {mailing.scheduleDate ? new Date(mailing.scheduleDate).toLocaleString() : 'N/A'}
                                    </Typography>
                                    <Typography variant="body2">
                                        Recurring: {mailing.recurringTypeCode && mailing.recurringStartDate
                                            ? formatRecurringString(mailing.recurringTypeCode, mailing.recurringStartDate)
                                            : 'None'}
                                    </Typography>
                                </CardContent>
                                <Box>
                                    <IconButton onClick={() => handleView(mailing)}>
                                        <VisibilityIcon />
                                    </IconButton>
                                    <IconButton onClick={() => handleCopy(mailing)}>
                                        <ContentCopyIcon />
                                    </IconButton>
                                    <IconButton color="secondary" onClick={() => handleCancelClick(mailing)}>
                                        <CancelIcon />
                                    </IconButton>
                                </Box>
                            </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={() => 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: 'scheduleDate', sort: 'asc' }], // Default sort by scheduleDate, descending
                        },
                    }}
                    pageSizeOptions={[10, 20, 50, 100]}
                />
            )}
            </Box>
            {viewOpen && (
                <MailingView
                    open={viewOpen}
                    mailing={selectedRow}
                    onClose={() => setViewOpen(false)}
                />
            )}

            {editOpen && (
                <MailingEdit
                    open={editOpen}
                    mailing={selectedRow}
                    onClose={(reason) => { if (reason !== 'backdropClick') setEditOpen(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 ScheduleMailings;