import { useEffect } from "react";
import { Controller, useForm } from "react-hook-form";
import { zodResolver } from "@hookform/resolvers/zod";
import { useNavigate, useParams } from "react-router";
import {
  Alert,
  Box,
  Button,
  CircularProgress,
  FormControl,
  FormControlLabel,
  InputLabel,
  MenuItem,
  Paper,
  Select,
  Stack,
  Switch,
  TextField,
  Typography,
} from "@mui/material";
import {
  pmScheduleDefaultValues,
  pmScheduleSchema,
  type PmScheduleFormValues,
} from "@/domain/pm-schedules/schemas/pm-schedule-schema";
import { usePmScheduleDetail } from "@/domain/pm-schedules/use-cases/use-pm-schedule-detail";
import { usePmScheduleFormOptions } from "@/domain/pm-schedules/use-cases/use-pm-schedule-form-options";
import { useSavePmSchedule } from "@/domain/pm-schedules/use-cases/use-save-pm-schedule";
import { toDateInputValue } from "@/lib/time-utils";

export default function PmScheduleFormPage() {
  const { id } = useParams();
  const navigate = useNavigate();
  const isEdit = Boolean(id);

  const { data: schedule, isLoading, error } = usePmScheduleDetail(id);
  const {
    assets,
    locations,
    isLoading: optionsLoading,
    error: optionsError,
  } = usePmScheduleFormOptions();
  const savePmSchedule = useSavePmSchedule(id);

  const {
    register,
    handleSubmit,
    reset,
    control,
    formState: { errors },
  } = useForm<PmScheduleFormValues>({
    resolver: zodResolver(pmScheduleSchema),
    defaultValues: pmScheduleDefaultValues,
  });

  useEffect(() => {
    if (schedule && isEdit) {
      reset({
        name: schedule.name,
        frequency: schedule.frequency as PmScheduleFormValues["frequency"],
        startDate: toDateInputValue(schedule.startDate),
        isActive: schedule.isActive,
        assetId: schedule.assetId,
        locationId: schedule.locationId,
      });
    }
  }, [schedule, isEdit, reset]);

  if ((isEdit && isLoading) || optionsLoading) {
    return (
      <Box className="flex justify-center p-10">
        <CircularProgress />
      </Box>
    );
  }

  return (
    <Box className="mx-auto max-w-3xl p-4">
      <Paper variant="outlined" className="p-6">
        <Stack spacing={3}>
          <Typography variant="h5">{isEdit ? "Edit PM Schedule" : "Create PM Schedule"}</Typography>

          {Boolean(error) && <Alert severity="error">Failed to load PM schedule</Alert>}
          {Boolean(optionsError) && (
            <Alert severity="error">
              {optionsError instanceof Error ? optionsError.message : "Failed to load form options"}
            </Alert>
          )}

          <Box component="form" onSubmit={handleSubmit((values) => savePmSchedule.mutate(values))}>
            <Stack spacing={3}>
              <TextField
                label="Name"
                required
                fullWidth
                error={Boolean(errors.name)}
                helperText={errors.name?.message}
                {...register("name")}
              />

              <Controller
                name="frequency"
                control={control}
                render={({ field }) => (
                  <FormControl fullWidth>
                    <InputLabel>Frequency</InputLabel>
                    <Select label="Frequency" value={field.value} onChange={field.onChange}>
                      {["Daily", "Weekly", "Monthly", "Quarterly", "Semi-Annual", "Annual"].map(
                        (value) => (
                          <MenuItem key={value} value={value}>
                            {value}
                          </MenuItem>
                        ),
                      )}
                    </Select>
                  </FormControl>
                )}
              />

              <TextField
                label="Start Date"
                type="date"
                required
                fullWidth
                slotProps={{ inputLabel: { shrink: true } }}
                error={Boolean(errors.startDate)}
                helperText={errors.startDate?.message}
                {...register("startDate")}
              />

              <Controller
                name="assetId"
                control={control}
                render={({ field }) => (
                  <FormControl fullWidth>
                    <InputLabel>Asset</InputLabel>
                    <Select
                      label="Asset"
                      value={field.value ?? ""}
                      onChange={(event) => {
                        const value = String(event.target.value);
                        field.onChange(value === "" ? null : Number(value));
                      }}
                    >
                      <MenuItem value="">
                        <em>None</em>
                      </MenuItem>
                      {assets.map((asset) => (
                        <MenuItem key={String(asset.id)} value={asset.id}>
                          {asset.name || asset.assetCode}
                        </MenuItem>
                      ))}
                    </Select>
                  </FormControl>
                )}
              />

              <Controller
                name="locationId"
                control={control}
                render={({ field }) => (
                  <FormControl fullWidth>
                    <InputLabel>Location</InputLabel>
                    <Select
                      label="Location"
                      value={field.value ?? ""}
                      onChange={(event) => {
                        const value = String(event.target.value);
                        field.onChange(value === "" ? null : Number(value));
                      }}
                    >
                      <MenuItem value="">
                        <em>None</em>
                      </MenuItem>
                      {locations.map((location) => (
                        <MenuItem key={String(location.id)} value={location.id}>
                          {location.name}
                        </MenuItem>
                      ))}
                    </Select>
                  </FormControl>
                )}
              />

              <Controller
                name="isActive"
                control={control}
                render={({ field }) => (
                  <FormControlLabel
                    control={<Switch checked={field.value} onChange={field.onChange} />}
                    label="Active"
                  />
                )}
              />

              <Stack
                direction="row"
                spacing={2}
                sx={{
                  justifyContent: "flex-end",
                }}
              >
                <Button variant="outlined" onClick={() => navigate("/pmschedules")}>
                  Cancel
                </Button>
                <Button type="submit" variant="contained" disabled={savePmSchedule.isPending}>
                  {savePmSchedule.isPending ? "Saving..." : isEdit ? "Update" : "Create"}
                </Button>
              </Stack>
            </Stack>
          </Box>
        </Stack>
      </Paper>
    </Box>
  );
}