import { httpProxy } from "utils/proxy/http";
import { formatApiCall } from "utils/proxy/api-helpers";
import getServiceWidget from "utils/config/service-helpers";
import createLogger from "utils/logger";
import widgets from "widgets/widgets";

const proxyName = "suwayomiProxyHandler";
const logger = createLogger(proxyName);

const countsToExtract = {
  download: {
    condition: (c) => c.isDownloaded,
    gqlCondition: "isDownloaded: true",
  },
  nondownload: {
    condition: (c) => !c.isDownloaded,
    gqlCondition: "isDownloaded: false",
  },
  read: {
    condition: (c) => c.isRead,
    gqlCondition: "isRead: true",
  },
  unread: {
    condition: (c) => !c.isRead,
    gqlCondition: "isRead: false",
  },
  downloadedread: {
    condition: (c) => c.isDownloaded && c.isRead,
    gqlCondition: "isDownloaded: true, isRead: true",
  },
  downloadedunread: {
    condition: (c) => c.isDownloaded && !c.isRead,
    gqlCondition: "isDownloaded: true, isRead: false",
  },
  nondownloadedread: {
    condition: (c) => !c.isDownloaded && c.isRead,
    gqlCondition: "isDownloaded: false, isRead: true",
  },
  nondownloadedunread: {
    condition: (c) => !c.isDownloaded && !c.isRead,
    gqlCondition: "isDownloaded: false, isRead: false",
  },
};

function makeBody(fields, category = "all") {
  if (Number.isNaN(Number(category))) {
    let query = "";
    fields.forEach((field) => {
      query += `
      ${field}: chapters(
        condition: {${countsToExtract[field].gqlCondition}}
        filter: {inLibrary: {equalTo: true}}
      ) {
        totalCount
      }`;
    });
    return JSON.stringify({
      operationName: "Counts",
      query: `
      query Counts {
        ${query}
      }`,
    });
  }

  return JSON.stringify({
    operationName: "category",
    query: `
    query category($id: Int!) {
      category(id: $id) {
        # name
        mangas {
          nodes {
            chapters {
              nodes {
                isRead
                isDownloaded
              }
            }
          }
        }
      }
    }`,
    variables: {
      id: Number(category),
    },
  });
}

function extractCounts(responseJSON, fields) {
  if (!("category" in responseJSON.data)) {
    return fields.map((field) => ({
      count: responseJSON.data[field].totalCount,
      label: `suwayomi.${field}`,
    }));
  }
  const tmp = responseJSON.data.category.mangas.nodes.reduce(
    (accumulator, manga) => {
      manga.chapters.nodes.forEach((chapter) => {
        fields.forEach((field, i) => {
          if (countsToExtract[field].condition(chapter)) {
            accumulator[i] += 1;
          }
        });
      });
      return accumulator;
    },
    [0, 0, 0, 0],
  );
  return fields.map((field, i) => ({
    count: tmp[i],
    label: `suwayomi.${field}`,
  }));
}

export default async function suwayomiProxyHandler(req, res) {
  const { group, service, endpoint } = req.query;

  if (!group || !service) {
    logger.debug("Invalid or missing service '%s' or group '%s'", service, group);
    return res.status(400).json({ error: "Invalid proxy service type" });
  }

  const widget = await getServiceWidget(group, service);

  if (!widget) {
    logger.debug("Invalid or missing widget for service '%s' in group '%s'", service, group);
    return res.status(400).json({ error: "Invalid proxy service type" });
  }

  if (!widget.fields || widget.fields.length === 0) {
    widget.fields = ["download", "nondownload", "read", "unread"];
  } else if (widget.fields.length > 4) {
    widget.fields = widget.fields.slice(0, 4);
  }

  const url = new URL(formatApiCall(widgets[widget.type].api, { endpoint, ...widget }));

  const body = makeBody(widget.fields, widget.category);

  const headers = {
    "Content-Type": "application/json",
  };

  if (widget.username && widget.password) {
    headers.Authorization = `Basic ${Buffer.from(`${widget.username}:${widget.password}`).toString("base64")}`;
  }

  const [status, contentType, data] = await httpProxy(url, {
    method: "POST",
    body,
    headers,
  });

  if (status === 401) {
    logger.error("Invalid or missing username or password for service '%s' in group '%s'", service, group);
    return res.status(status).send({ error: { message: "401: unauthorized, username or password is incorrect." } });
  }

  if (status !== 200) {
    logger.error(
      "Error getting data from Suwayomi for service '%s' in group '%s': %d.  Data: %s",
      service,
      group,
      status,
      data,
    );
    return res.status(status).send({ error: { message: "Error getting data. body: %s, data: %s", body, data } });
  }

  const returnData = extractCounts(JSON.parse(data), widget.fields);

  if (contentType) res.setHeader("Content-Type", contentType);
  return res.status(status).send(returnData);
}