import Prisma from "@prisma/client";
const prisma = new Prisma.PrismaClient();

import {
  applyKey,
  hasPermission,
  listPermissions,
  revokeKey,
} from "./permission.js";

// Get info API endpoint (/api/info)
// Returns information about the requesting session
export async function getInfo(req, res) {
  // If server has auth disabled
  if (!req.locals.session) {
    res.send({
      authenticated: true,
      appliedKeys: [],
      permissions: [],
    });
    return;
  }

  const session = await prisma.session.findUnique({
    where: {
      token: req.locals.session,
    },
    include: {
      appliedKeys: {
        select: {
          key: true,
          permissions: true,
          validUntil: true,
        },
      },
    },
  });

  res.send({
    authenticated: true,
    appliedKeys: session.appliedKeys,
    permissions: await listPermissions(session.token),
  });
}

// Put and Delete key API endpoints (/api/key)
// Applies or revokes a key from the requesting user's session
export async function putKey(req, res) {
  if (await applyKey(req.locals.session, req.query.key)) {
    res.status(200).send();
  } else {
    res.status(400).send({
      success: false,
      error: "invalid_key",
      message: "This key does not exist",
    });
  }
}

export async function deleteKey(req, res) {
  if (await revokeKey(req.locals.session, req.query.key)) {
    res.status(200).send();
  } else {
    res.status(400).send();
  }
}

// Get timetable API endpoint (/api/timetable)
// Returns timetable data for requested class if available
export async function getTimetable(req, res) {
  if (!req.query.class) {
    res.status(400).send({
      success: false,
      error: "missing_parameter",
      message: "No class parameter provided",
    });
    return;
  }
  const requestedClass = req.query.class.toLowerCase();
  const timetables = await prisma.timetable.findMany({
    where: {
      class: requestedClass,
    },
    orderBy: {
      updatedAt: "desc",
    },
  });
  const times = await prisma.time.findMany();
  res.send({
    timetables,
    times,
  });
}

// Edit timetable API endpoint (/api/timetable)
// Updates a remote timetable with the requested data
export async function putTimetable(req, res) {
  const timetableId = parseInt(req.query.id);
  const data = req.body.data;
  if (
    !(await hasPermission(req.locals.session, "timetable.update", timetableId))
  ) {
    res.status(401).send({
      success: false,
      error: "missing_permission",
      message: "You don't have permission to update this timetable!",
    });
    return;
  }

  await prisma.timetable.update({
    where: {
      id: timetableId,
    },
    data: {
      data,
      title: req.body.title,
    },
  });
  res.status(201).send();
}

// Helper function for converting a date string
// (eg. "2022-06-02" or "1654128000000") to a
// unix timestamp
function convertToDate(dateQuery) {
  var date;
  if (dateQuery.match(/^[0-9]+$/) != null) date = parseInt(dateQuery);
  else date = dateQuery;
  date = new Date(date).setUTCHours(0, 0, 0, 0);
  return new Date(date);
}

// Get substitutions API endpoint (/api/substitutions)
// Returns all known substitutions for requested date / class
// If no class is supplied, all substitutions are returned
export async function getSubstitutions(req, res) {
  const requestedClass = (req.query.class || "").toLowerCase();
  var from, to, date;
  // Check if from or to date is set in request
  if (req.query.from && req.query.to) {
    from = convertToDate(req.query.from);
    to = convertToDate(req.query.to);
  } else if (req.query.date) {
    date = convertToDate(req.query.date);
  }

  const prismaOptions = {
    where: {
      removed: false,
    },
    orderBy: {
      lesson: "asc",
    },
  };
  if (requestedClass) {
    prismaOptions.where.class = { has: requestedClass };
  }
  // Choose which date to use in database query
  if (from && to) {
    prismaOptions.where.date = {
      gte: from,
      lte: to,
    };
  } else if (date) {
    prismaOptions.where.date = date;
  } else {
    // Default to all substitutions for today and in the future
    prismaOptions.where.date = {
      gte: new Date(new Date().setUTCHours(0, 0, 0, 0)),
    };
  }

  const rawSubstitutions = await prisma.substitution.findMany(prismaOptions);
  const substitutions = rawSubstitutions.map((element) => {
    const substitution = {
      id: element.id,
      class: element.class,
      type: element.type,
      rawType: element.rawType,
      lesson: element.lesson,
      date: new Date(element.date).getTime(),
      notes: element.notes,
      teacher: element.teacher,
      change: {},
    };
    if (element.changedRoom) substitution.change.room = element.changedRoom;
    if (element.changedTeacher)
      substitution.change.teacher = element.changedTeacher;
    if (element.changedSubject)
      substitution.change.subject = element.changedSubject;
    return substitution;
  });
  res.send(substitutions);
}

// Get history API endpoint (/api/history)
// Returns history of changes for all substituions in the date range
// for the requested class if supplied
export async function getHistory(req, res) {
  const requestedClass = (req.query.class || "").toLowerCase();
  var from, to, date;
  // Check if from or to date is set in request
  if (req.query.from && req.query.to) {
    from = convertToDate(req.query.from);
    to = convertToDate(req.query.to);
  } else if (req.query.date) {
    date = convertToDate(req.query.date);
  }

  const prismaOptions = {
    where: {
      substitution: {},
    },
    include: {
      substitution: true,
    },
    orderBy: {
      createdAt: "desc",
    },
  };
  if (requestedClass) {
    prismaOptions.where.substitution.class = { has: requestedClass };
  }
  // Choose which date to use in database query
  if (from && to) {
    prismaOptions.where.substitution.date = {
      gte: from,
      lte: to,
    };
  } else if (date) {
    prismaOptions.where.substitution.date = date;
  } else {
    // Default to history of all substitutions for today and in the future
    prismaOptions.where.substitution.date = {
      gte: new Date(new Date().setUTCHours(0, 0, 0, 0)),
    };
  }

  const rawChanges = await prisma.substitutionChange.findMany(prismaOptions);
  const changes = rawChanges.map((element) => {
    return {
      id: element.id,
      type: element.type,
      class: element.substitution.class,
      substitutionId: element.substitutionId,
      lesson: element.substitution.lesson,
      updatedAt: new Date(element.createdAt).getTime(),
      date: new Date(element.substitution.date).getTime(),
      teacher: element.teacher,
      change: element.changes,
      notes: element.notes,
      parseEventId: element.parseEventId,
    };
  });
  res.send(changes);
}

// Get classes API endpoints (/api/classes)
// Get all available classes where timetable and
// substitutions can be requested for
export async function getClasses(_req, res) {
  const classes = await prisma.class.findMany({
    select: {
      name: true,
      regex: false,
    },
    orderBy: {
      name: "asc",
    },
  });
  // Only return the name of the class
  const classList = classes.map((element) => element.name);
  res.send(classList);
}