import type { Request, Response } from "express";
import { ProjectHistoryOperationUnavailableError } from "../../domain/errors/project-history-operation-unavailable.error.js";
import { ProjectRevisionConflictError } from "../../domain/errors/project-revision-conflict.error.js";
import {
  executeProjectCommandSchema,
  executeProjectHistoryCommandSchema,
} from "../../shared/validation/project-command.schemas.js";
import { projectCommandService } from "../composition/project-command-stores.js";

export function executeProjectCommand(req: Request, res: Response) {
  const projectId = getProjectId(req, res);
  if (!projectId) {
    return;
  }
  const parsed = executeProjectCommandSchema.safeParse(req.body);
  if (!parsed.success) {
    return res.status(400).json({ error: parsed.error.flatten() });
  }

  try {
    return res.json(
      projectCommandService.executeUser({
        projectId,
        ...parsed.data,
      })
    );
  } catch (error) {
    return respondWithProjectCommandError(error, res);
  }
}

export function undoProjectCommand(req: Request, res: Response) {
  return executeHistoryCommand(req, res, "undo");
}

export function redoProjectCommand(req: Request, res: Response) {
  return executeHistoryCommand(req, res, "redo");
}

function executeHistoryCommand(
  req: Request,
  res: Response,
  direction: "undo" | "redo"
) {
  const projectId = getProjectId(req, res);
  if (!projectId) {
    return;
  }
  const parsed = executeProjectHistoryCommandSchema.safeParse(req.body);
  if (!parsed.success) {
    return res.status(400).json({ error: parsed.error.flatten() });
  }

  try {
    const result = projectCommandService[direction]({
      projectId,
      ...parsed.data,
    });
    return res.json(result);
  } catch (error) {
    return respondWithProjectCommandError(error, res);
  }
}

function getProjectId(req: Request, res: Response) {
  const { projectId } = req.params;
  if (typeof projectId !== "string" || !projectId.trim()) {
    res.status(400).json({ error: "Invalid projectId" });
    return null;
  }
  return projectId;
}

export function respondWithProjectCommandError(
  error: unknown,
  res: Response
) {
  if (error instanceof ProjectRevisionConflictError) {
    return res.status(409).json({
      error: error.message,
      code: "PROJECT_REVISION_CONFLICT",
      expectedRevision: error.expectedRevision,
      currentRevision: error.actualRevision,
    });
  }
  if (error instanceof ProjectHistoryOperationUnavailableError) {
    return res.status(409).json({
      error: error.message,
      code: "PROJECT_HISTORY_OPERATION_UNAVAILABLE",
      direction: error.direction,
    });
  }
  return res.status(400).json({
    error:
      error instanceof Error
        ? error.message
        : "Project command could not be executed.",
  });
}