import { useMemo } from "react";
import { type QueryClient, useMutation, useQueryClient } from "@tanstack/react-query";
import { toast } from "react-toastify";
import { workOrdersApi } from "@/domain/work-orders/api/work-orders-api";
import {
  boardPatchErrorMessage,
  BoardPatchConflictError,
  BoardPatchPartialSaveError,
  BoardPatchValidationError,
  NO_PERSISTABLE_FIELDS_MESSAGE,
} from "@/domain/work-orders/errors/board-patch-errors";
import { mapApiStatusToWizard } from "@/domain/work-orders/mappers/wizard-draft-mapper";
import {
  buildBoardPatchPayload,
  expandTablePatchToBoardFieldOps,
  isLocalOnlyTablePatch,
  type BoardOp,
} from "@/domain/work-orders/mappers/work-order-board-patch-mapper";
import { mapWorkOrderTableRow } from "@/domain/work-orders/mappers/work-order-mapper";
import type { WorkOrderBoardDetail } from "@/domain/work-orders/types/work-order-board-detail";
import type {
  WorkOrderTablePatch,
  WorkOrderTableRow,
} from "@/domain/work-orders/types/work-order-table-row";
import { deriveDayFields } from "@/domain/work-orders/utils/table-day-utils";
import { enrichTableRow } from "@/domain/work-orders/utils/table-filter-utils";
import {
  maybeAutoSchedulePatch,
  mergeAutoSchedulePatch,
} from "@/domain/work-orders/utils/wo-lifecycle-transitions";
import { createWorkOrderPatchQueue } from "@/domain/work-orders/utils/work-order-patch-queue";
import { queryKeys } from "@/infra/query-key/query-key";

export { maybeAutoSchedulePatch };

export type { WorkOrderTablePatch };

export type WorkOrderTablePatchOptions = {
  onSuccess?: () => void;
  onError?: (error: Error) => void;
  /** Patch base when the loaded list no longer holds the work order (e.g. moved to another week). */
  fallbackRow?: WorkOrderTableRow;
};

export type WorkOrderTablePatchFn = (
  id: string | number,
  patch: WorkOrderTablePatch,
  options?: WorkOrderTablePatchOptions,
) => void;

export type WorkOrderTablePatchHandlers = {
  onPatch: (id: string | number, patch: WorkOrderTablePatch) => void;
  clearPatch: (id: string | number) => void;
  getRow?: (id: string | number) => WorkOrderTableRow | undefined;
};

type PatchResult =
  { kind: "local"; patch: WorkOrderTablePatch } | { kind: "board"; row: WorkOrderTableRow };

function isPocOp(op: BoardOp): op is Extract<BoardOp, { kind: "poc" }> {
  return "kind" in op && op.kind === "poc";
}

async function applyBoardOp(
  id: string | number,
  op: BoardOp,
  row: WorkOrderTableRow,
): Promise<WorkOrderTableRow> {
  if (isPocOp(op)) {
    if (!row.rowVersion) {
      throw new Error("workOrderVersion is required for board patch");
    }
    return workOrdersApi.updatePoc(id, {
      pocName: op.pocName ?? row.pocName,
      pocPhone: op.pocPhone ?? row.pocPhone,
      pocNotes: op.pocNotes ?? row.pocNotes,
      workOrderVersion: row.rowVersion,
    });
  }

  return workOrdersApi.patchBoardField(id, buildBoardPatchPayload(op, row));
}

async function applyBoardFieldOps(
  id: string | number,
  patch: WorkOrderTablePatch,
  getRow: ((id: string | number) => WorkOrderTableRow | undefined) | undefined,
): Promise<WorkOrderTableRow> {
  const current = getRow?.(id);
  const ops = expandTablePatchToBoardFieldOps(patch, current);
  if (ops.length === 0) {
    throw new BoardPatchValidationError("NoPersistableFields", NO_PERSISTABLE_FIELDS_MESSAGE);
  }

  if (!current?.rowVersion) {
    throw new Error("Missing work order version for board patch. Refresh and retry.");
  }

  let latest = current;
  let completedOps = 0;
  for (const op of ops) {
    try {
      latest = await applyBoardOp(id, op, latest);
      completedOps += 1;
    } catch (error) {
      if (completedOps > 0) {
        throw new BoardPatchPartialSaveError(latest, error);
      }
      throw error;
    }
  }

  return latest;
}

/** Board fields (including completedDate) use PATCH …/board — never legacy EditWorkorder. */
export async function runWorkOrderTablePatch(
  id: string | number,
  patch: WorkOrderTablePatch,
  getRow: ((id: string | number) => WorkOrderTableRow | undefined) | undefined,
): Promise<PatchResult> {
  if (isLocalOnlyTablePatch(patch)) {
    return { kind: "local", patch };
  }

  const boardRow = await applyBoardFieldOps(id, patch, getRow);
  return { kind: "board", row: boardRow };
}

function readDetailRow(
  queryClient: QueryClient,
  id: string | number,
): WorkOrderTableRow | undefined {
  return queryClient.getQueryData<WorkOrderBoardDetail>(queryKeys.workOrders.boardDetail(id))?.info;
}

/** Carry a saved row's version into the open panel's detail before the next queued patch runs. */
function syncDetailRowVersion(
  queryClient: QueryClient,
  id: string | number,
  row: WorkOrderTableRow,
) {
  queryClient.setQueryData<WorkOrderBoardDetail>(queryKeys.workOrders.boardDetail(id), (detail) =>
    detail && row.rowVersion
      ? {
          ...detail,
          info: {
            ...detail.info,
            rowVersion: row.rowVersion,
            dispatchRowVersion: row.dispatchRowVersion || detail.info.dispatchRowVersion,
          },
        }
      : detail,
  );
}

type SavedRowSync = {
  queryClient: QueryClient;
  /** Last server row each patch returned, for panels whose detail query never cached data. */
  savedRows: Map<string, WorkOrderTableRow>;
};

function recordSavedRow(
  { queryClient, savedRows }: SavedRowSync,
  id: string | number,
  row: WorkOrderTableRow,
) {
  savedRows.set(String(id), row);
  syncDetailRowVersion(queryClient, id, row);
}

async function runPatchAndSyncDetail(
  sync: SavedRowSync,
  id: string | number,
  patch: WorkOrderTablePatch,
  readBase: (id: string | number) => WorkOrderTableRow | undefined,
): Promise<PatchResult> {
  try {
    const result = await runWorkOrderTablePatch(id, patch, readBase);
    if (result.kind === "board") recordSavedRow(sync, id, result.row);
    return result;
  } catch (error) {
    if (error instanceof BoardPatchPartialSaveError) {
      recordSavedRow(sync, id, error.partialRow);
    }
    throw error;
  }
}

export function useWorkOrderTableMutations(
  onPatchOrHandlers:
    ((id: string | number, patch: WorkOrderTablePatch) => void) | WorkOrderTablePatchHandlers,
  getRowArg?: (id: string | number) => WorkOrderTableRow | undefined,
) {
  const handlers: WorkOrderTablePatchHandlers =
    typeof onPatchOrHandlers === "function"
      ? {
          onPatch: onPatchOrHandlers,
          clearPatch: () => undefined,
          getRow: getRowArg,
        }
      : onPatchOrHandlers;

  const { onPatch, clearPatch, getRow } = handlers;
  const queryClient = useQueryClient();
  const enqueuePatch = useMemo(() => createWorkOrderPatchQueue(), []);
  const savedRows = useMemo(() => new Map<string, WorkOrderTableRow>(), []);

  const invalidate = () => {
    void queryClient.invalidateQueries({ queryKey: queryKeys.workOrders.all });
  };

  const patchMutation = useMutation({
    meta: { suppressErrorToast: true },
    mutationFn: ({
      id,
      persistPatch,
      baseRow,
      fallbackRow,
    }: {
      id: string | number;
      patch: WorkOrderTablePatch;
      persistPatch: WorkOrderTablePatch;
      /** Server row from a just-settled patch; its rowVersion is fresher than the table snapshot. */
      baseRow?: WorkOrderTableRow;
      /** Used when neither the table nor the detail cache holds the work order. */
      fallbackRow?: WorkOrderTableRow;
    }) =>
      enqueuePatch(id, () =>
        runPatchAndSyncDetail(
          { queryClient, savedRows },
          id,
          persistPatch,
          baseRow
            ? () => baseRow
            : (rowId) =>
                getRow?.(rowId) ??
                readDetailRow(queryClient, rowId) ??
                savedRows.get(String(rowId)) ??
                fallbackRow,
        ),
      ),
    onMutate: async ({ id, persistPatch }) => {
      onPatch(id, persistPatch);
    },
    onSuccess: (result, { id }) => {
      if (result.kind === "board") {
        onPatch(id, result.row);
      }
      invalidate();
    },
    onError: (error: Error, { id }) => {
      if (error instanceof BoardPatchPartialSaveError) {
        onPatch(id, error.partialRow);
        toast.error(error.message);
        invalidate();
        return;
      }

      if (error instanceof BoardPatchConflictError && error.currentState) {
        onPatch(id, error.currentState);
        toast.error(boardPatchErrorMessage(error));
      } else {
        clearPatch(id);
        toast.error(boardPatchErrorMessage(error));
      }
      invalidate();
    },
  });

  const patchField: WorkOrderTablePatchFn = (id, patch, options) => {
    const fallbackRow = options?.fallbackRow;
    const persistPatch = mergeAutoSchedulePatch(getRow?.(id) ?? fallbackRow, patch);
    void patchMutation.mutateAsync({ id, patch, persistPatch, fallbackRow }).then(
      () => options?.onSuccess?.(),
      (error: Error) => options?.onError?.(error),
    );
  };

  const patchFieldAsync = (
    id: string | number,
    patch: WorkOrderTablePatch,
    baseRow?: WorkOrderTableRow,
    fallbackRow?: WorkOrderTableRow,
  ) => {
    const persistPatch = mergeAutoSchedulePatch(baseRow ?? getRow?.(id) ?? fallbackRow, patch);
    return patchMutation.mutateAsync({ id, patch, persistPatch, baseRow, fallbackRow });
  };

  return {
    patchField,
    patchFieldAsync,
    isPending: patchMutation.isPending,
  };
}

export function tableRowFromDetail(detail: Awaited<ReturnType<typeof workOrdersApi.getById>>) {
  return enrichTableRow(
    mapWorkOrderTableRow({
      ...detail,
      status: mapApiStatusToWizard(detail.status),
      scheduledOn: detail.scheduledDate,
      woNumber: detail.internalWONumber || detail.workOrderNumber,
      dispatcherName: detail.assignedTo,
      pm: detail.problem,
      type: detail.source,
    }),
  );
}

/**
 * Build a schedule table patch. Clearing the schedule optimistically clears
 * `isAddOn`; day/week moves leave `isAddOn` for the board PATCH response.
 */
export function applySchedulePatch(
  scheduledOn: string,
  scheduleWeekOnly: boolean,
): WorkOrderTablePatch {
  if (scheduleWeekOnly) {
    return {
      scheduledOn: "",
      targetWeek: scheduledOn,
      scheduleWeekOnly: true,
      scheduleEnd: "",
      schedMode: "week",
      ...deriveDayFields(""),
    };
  }
  const trimmed = scheduledOn.trim();
  if (!trimmed) {
    return {
      scheduledOn: "",
      scheduleWeekOnly: false,
      targetWeek: "",
      scheduleEnd: "",
      schedMode: undefined,
      isAddOn: false,
      ...deriveDayFields(""),
    };
  }
  return {
    scheduledOn: trimmed,
    scheduleWeekOnly: false,
    targetWeek: "",
    scheduleEnd: "",
    schedMode: "date",
    ...deriveDayFields(trimmed),
  };
}

/** Range lands on the first day; end/mode stay optimistic (no board API field). */
export function applyScheduleRangePatch(start: string, end: string): WorkOrderTablePatch {
  return {
    ...applySchedulePatch(start, false),
    scheduleEnd: end,
    schedMode: "range",
  };
}