#ifndef MuonDetId_CSCIndexerOldPostls1_h
#define MuonDetId_CSCIndexerOldPostls1_h

/** \class CSCIndexerOldPostls1
 * Creates a linear index for various sublevels of the endcap muon CSC system.
 *
 * It supplies a linear index for:
 * 1. Each chamber of the CSC system: range 1-468 (CSC system as installed 2008)
 * 469-540 for ME42 <br>
 * 2. Each layer of the CSC system: range 1-2808 (CSCs 2008) 2809-3240 for ME42
 * <br>
 * 3. Each strip channel of the CSC system: range 1-217728 (CSCs 2008)
 * 217729-252288 for ME42 <br>
 * 4. Each Buckeye chip (1 for each layer in each CFEB)of the CSC system: range
 * 1-13608 (CSCs 2008) 13609-15768 for ME42 <br>
 * 5. Each Gas Gain Sector (1 for each [CFEB*HV segment] combination in each
 * layer): range 1-45144 (CSCs 2008) 45145-55944 for ME42 <br>
 * 6. Extended for unganged ME1a, appended to the standard list: only in the
 * strip list 252289-273024 (i.e. an extra 2 x 36 x 6 x 48 = 20736 channels)
 *
 * The chamber and layer may be specified by CSCDetId or labels for endcap,
 * station, ring, chamber, layer. The strip channel is a value 1-80 (or 64: ME13
 * chambers have only 64 channels.) The chip number is a value 1-30 (or 24: ME13
 * chambers have only 24 chips.)
 *
 * The main user interface is the set of functions <br>
 *   chamberIndex(.) <br>
 *   layerIndex(.) <br>
 *   stripChannelIndex(.) <br>
 *   chipIndex(.) <br>
 * But the other functions are public since they may be useful in contexts other
 * than for Conditions Data for which the above functions are intended.
 *
 * \warning This class is hard-wired for the CSC system at start-up of CMS in
 * 2008. with rings ME11, ME12, ME13, ME21, ME22, ME31, ME32, ME41 totalling 234
 * chambers per endcap. But ME42 is appended (to permit simulation studies), so
 * the chamber order is <br> +z ME11, ME12, ME13, ME21, ME22, ME31, ME32, ME41,
 * <br> -z ME11, ME12, ME13, ME21, ME22, ME31, ME32, ME41, <br> +z ME42, -z ME42
 * <br>
 *
 * Further it is extended for hypothetical unganged ME1a strip channels.
 * The strip list then appends
 * +z ME1a, -z ME1a <br>
 *
 * \warning This intentionally has "magic numbers galore" which, supposedly, is
 * for better performance.
 *
 * \warning EVERY LABEL COUNTS FROM ONE NOT ZERO.
 *
 */

#include <DataFormats/MuonDetId/interface/CSCDetId.h>
#include <iosfwd>
#include <tuple>
#include <utility>  // for pair
#include <vector>

class CSCIndexerOldPostls1 {
public:
  typedef uint16_t IndexType;
  typedef uint32_t LongIndexType;

  typedef std::tuple<CSCDetId,   // id
                     IndexType,  // HV segment
                     IndexType   // chip
                     >
      GasGainTuple;

  static const IndexType MAX_CHAMBER_INDEX = 540;
  static const IndexType MAX_LAYER_INDEX = 3240;
  static const LongIndexType MAX_STRIP_CHANNEL_INDEX = 273024;
  static const IndexType MAX_CHIP_INDEX = 17064;
  static const IndexType MAX_GAS_GAIN_INDEX = 57240;

  CSCIndexerOldPostls1() {}
  ~CSCIndexerOldPostls1() {}

  /**
   * Starting index for first chamber in ring 'ir' of station 'is' in endcap
   * 'ie', in range 1-468 (CSCs 2008) or 469-540 (ME42).
   *
   * WARNING: Considers both ME1a and ME1b to be part of one ME11 chamber
   *          (result would be the same for is=1 and ir=1 or 4).
   */
  IndexType startChamberIndexInEndcap(IndexType ie, IndexType is, IndexType ir) const {
    const IndexType nschin[32] = {1,   37,  73,  1,   109, 127, 0, 0, 163, 181, 0, 0, 217, 469, 0, 0,
                                  235, 271, 307, 235, 343, 361, 0, 0, 397, 415, 0, 0, 451, 505, 0, 0};
    return nschin[(ie - 1) * 16 + (is - 1) * 4 + ir - 1];
  }

  /**
   * Linear index for chamber 'ic' in ring 'ir' of station 'is' in endcap 'ie',
   * in range 1-468 (CSCs 2008) or 469-540 (ME42)
   *
   * WARNING: Considers both ME1a and ME1b to be part of one ME11 chamber
   *          (result would be the same for is=1 and ir=1 or 4).
   */
  IndexType chamberIndex(IndexType ie, IndexType is, IndexType ir, IndexType ic) const {
    return startChamberIndexInEndcap(ie, is, ir) + ic - 1;  // -1 so start index _is_ ic=1
  }

  /**
   * Linear index to label each CSC in CSC system.
   * Argument is the CSCDetId of some CSCChamber.
   *
   * Output is 1-468 (CSCs 2008) 469-540 (with ME42)
   *
   * WARNING: Considers both ME1a and ME1b to be part of one ME11 chamber
   *          (result would be the same for is=1 and ir=1 or 4).
   */
  IndexType chamberIndex(const CSCDetId &id) const {
    return chamberIndex(id.endcap(), id.station(), id.ring(), id.chamber());
  }

  /**
   * Linear index to label each hardware layer in CSC system.
   * Argument is the CSCDetId of some CSCLayer.
   *
   * Output is 1-2808 (CSCs 2008) 2809-3240 (ME42)
   *
   * WARNING: Considers both ME1a and ME1b to share layers of single ME11
   * chamber (result would be the same for is=1 and ir=1 or 4).
   */
  IndexType layerIndex(const CSCDetId &id) const {
    return layerIndex(id.endcap(), id.station(), id.ring(), id.chamber(), id.layer());
  }

  /**
   * Linear index for layer 'il' of chamber 'ic' in ring 'ir' of station 'is' in
   * endcap 'ie', in range 1-2808 (CSCs 2008) or 2809-3240 (ME42).
   *
   * WARNING: Considers both ME1a and ME1b to share layers of single ME11
   * chamber (result would be the same for is=1 and ir=1 or 4).
   */
  IndexType layerIndex(IndexType ie, IndexType is, IndexType ir, IndexType ic, IndexType il) const {
    return (chamberIndex(ie, is, ir, ic) - 1) * 6 + il;
  }

  /**
   * How many (physical hardware) rings are there in station is=1, 2, 3, 4 ?
   *
   * WARNING:
   * - ME1 has only 3 physical rings (the hardware) not 4 (virtual ring 4 is
   * used offline for ME1a).
   * - Includes ME42 so claims 2 rings in station 4.
   */
  IndexType ringsInStation(IndexType is) const {
    const IndexType nrings[5] = {0, 3, 2, 2, 2};  // rings per station
    return nrings[is];
  }

  /**
   * How many offline rings are there in station is=1, 2, 3, 4 ?
   *
   * WARNING:
   * - ME1 has 4 rings in the offline notation (virtual ring 4 is used for
   * ME1a).
   * - Includes ME42 so claims 2 rings in station 4.
   */
  IndexType offlineRingsInStation(IndexType is) const {
    const IndexType nrings[5] = {0, 4, 2, 2, 2};  // rings per station
    return nrings[is];
  }

  /**
   * How many chambers are there in ring ir of station is?
   *
   * Works for ME1a (virtual ring 4 of ME1) too.
   */
  IndexType chambersInRingOfStation(IndexType is, IndexType ir) const {
    const IndexType nCinR[16] = {36, 36, 36, 36, 18, 36, 0, 0, 18, 36, 0, 0, 18, 36, 0, 0};  // chambers in ring
    return nCinR[(is - 1) * 4 + ir - 1];
  }

  /**
   * Number of strip channels per layer in a chamber in ring ir of station is.
   *
   * Station label range 1-4, Ring label range 1-4.
   * Works for ME1a input as is=1, ir=4.
   *
   * WARNING:
   * - ME1a channels are considered to be unganged i.e. 48 not the standard 16.
   * - ME1b keeps 80 channels for the indexing purposes, however channels 65-80
   * are ignored in the unganged case.
   */
  IndexType stripChannelsPerLayer(IndexType is, IndexType ir) const {
    const IndexType nSCinC[16] = {80, 80, 64, 48, 80, 80, 0, 0, 80, 80, 0, 0, 80, 80, 0, 0};
    return nSCinC[(is - 1) * 4 + ir - 1];
  }

  /**
   * Linear index for 1st strip channel in ring 'ir' of station 'is' in endcap
   * 'ie'.
   *
   * Endcap label range 1-2, Station label range 1-4, Ring label range 1-3.
   *
   * WARNING: ME1a channels are  NOT  considered the last 16 of the 80 total in
   * each layer of an ME11 chamber!
   */
  LongIndexType stripChannelStart(IndexType ie, IndexType is, IndexType ir) const {
    // These are in the ranges 1-217728 (CSCs 2008), 217729-252288 (ME42), and
    // 252289-273024 (unganged ME1a) There are 1-108884 channels per endcap
    // (CSCs 2008), 17280 channels per endcap (ME42), and 10368 channels per
    // endcap (unganged ME1a) Start of -z channels (CSCs 2008) is 108864 + 1 =
    // 108865 Start of +z (ME42) is 217728 + 1                  = 217729 Start
    // of -z (ME42) is 217728 + 1 + 17280          = 235009 Start of +z
    // (unganged ME1a) is 252288 + 1         = 252289 Start of -z (unganged
    // ME1a) is 252288 + 1 + 10368 = 262657
    const LongIndexType nStart[32] = {1, 17281,  34561,  252289, 48385, 57025,  0,      0,      74305,  82945,  0,
                                      0, 100225, 217729, 0,      0,     108865, 126145, 143425, 262657, 157249, 165889,
                                      0, 0,      183169, 191809, 0,     0,      209089, 235009, 0,      0};
    return nStart[(ie - 1) * 16 + (is - 1) * 4 + ir - 1];
  }

  /**
   * Linear index for strip channel istrip in layer 'il' of chamber 'ic' of ring
   * 'ir' in station 'is' of endcap 'ie'.
   *
   * Output is 1-217728 (CSCs 2008) or 217729-252288 (ME42) or 252289-273024
   * (unganged ME1a) WARNING: Supplying ME1a values returns index for unganged
   * ME1a channels, not for channels 65-80 of ME11.
   *
   * WARNING: Use at your own risk! You must input labels within hardware
   * ranges. No trapping on out-of-range values!
   */
  LongIndexType stripChannelIndex(
      IndexType ie, IndexType is, IndexType ir, IndexType ic, IndexType il, IndexType istrip) const {
    return stripChannelStart(ie, is, ir) + ((ic - 1) * 6 + il - 1) * stripChannelsPerLayer(is, ir) + (istrip - 1);
  }

  /**
   * Linear index for strip channel 'istrip' in layer labelled by CSCDetId 'id'.
   *
   * Output is 1-217728 (CSCs 2008) or 217729-252288 (ME42) or 252289-273024
   * (unganged ME1a)
   *
   * WARNING: Use at your own risk! The supplied CSCDetId must be a layer id.
   * No trapping on out-of-range values!
   */
  LongIndexType stripChannelIndex(const CSCDetId &id, IndexType istrip) const {
    return stripChannelIndex(id.endcap(), id.station(), id.ring(), id.chamber(), id.layer(), istrip);
  }

  /**
   * Number of Buckeye chips per layer in a chamber in ring ir of station is.
   *
   * Station label range 1-4, Ring label range 1-3.
   *
   * Works for ME1a input as is=1, ir=4
   * Considers ME42 as standard 5 chip per layer chambers.
   *
   * WARNING:
   * - ME1a channels are considered to be unganged and have their own 3 chips
   * (ME1b has 4 chips).
   * - ME1b keeps 5 chips for the indexing purposes, however indices for the
   * chip #5 are ignored in the unganged case.
   */
  IndexType chipsPerLayer(IndexType is, IndexType ir) const {
    const IndexType nCinL[16] = {5, 5, 4, 3, 5, 5, 0, 0, 5, 5, 0, 0, 5, 5, 0, 0};
    return nCinL[(is - 1) * 4 + ir - 1];
  }

  /**
   * Linear index for 1st Buckey chip in ring 'ir' of station 'is' in endcap
   * 'ie'.
   *
   * Endcap label range 1-2, Station label range 1-4, Ring label range 1-3.
   *
   * Works for ME1a input as is=1, ir=4
   * WARNING: ME1a channels are the last 3 of the 7 chips total in each layer of
   * an ME11 chamber,
   */
  IndexType chipStart(IndexType ie, IndexType is, IndexType ir) const {
    // These are in the ranges 1-13608 (CSCs 2008) and 13609-15768 (ME42) and
    // 15769-17064 (ME1a). There are 1-6804 chips per endcap (CSCs 2008) and
    // 1080 chips per endcap (ME42) and 648 chips per endcap (ME1a). Start of -z
    // channels (CSCs 2008) is 6804 + 1 = 6805 Start of +z (ME42) is 13608 + 1 =
    // 13609 Start of -z (ME42) is 13608 + 1 + 1080 = 14689 Start of +z (ME1a)
    // is 15768 + 1 = 15769 Start of -z (ME1a) is 15768 + 1 + 648 = 16417
    const IndexType nStart[32] = {1,    1081, 2161, 15769, 3025, 3565,  0, 0, 4645,  5185,  0, 0, 6265,  13609, 0, 0,
                                  6805, 7885, 8965, 16417, 9829, 10369, 0, 0, 11449, 11989, 0, 0, 13069, 14689, 0, 0};
    return nStart[(ie - 1) * 16 + (is - 1) * 4 + ir - 1];
  }

  /**
   * Linear index for Buckeye chip 'ichip' in layer 'il' of chamber 'ic' of ring
   * 'ir' in station 'is' of endcap 'ie'.
   *
   * Output is 1-13608 (CSCs 2008) or 13609-15768 (ME42) or 15769-17064 (ME1a).
   *
   * WARNING: Use at your own risk! You must input labels within hardware
   * ranges. No trapping on out-of-range values!
   */
  IndexType chipIndex(IndexType ie, IndexType is, IndexType ir, IndexType ic, IndexType il, IndexType ichip) const {
    // printf("ME%d/%d/%d/%d layer %d  chip %d chipindex
    // %d\n",ie,is,ir,ic,il,ichip,chipStart(ie,is,ir)+( (ic-1)*6 + il - 1
    // )*chipsPerLayer(is,ir) + (ichip-1));
    return chipStart(ie, is, ir) + ((ic - 1) * 6 + il - 1) * chipsPerLayer(is, ir) + (ichip - 1);
  }

  /**
   * Linear index for Buckeye chip 'ichip' in layer labelled by CSCDetId 'id'.
   *
   * Output is 1-13608 (CSCs 2008) or 13609-15768 (ME42) or 15769-17064 (ME1a).
   *
   * WARNING: Use at your own risk! The supplied CSCDetId must be a layer id.
   * No trapping on out-of-range values!
   */
  IndexType chipIndex(const CSCDetId &id, IndexType ichip) const {
    return chipIndex(id.endcap(), id.station(), id.ring(), id.chamber(), id.layer(), ichip);
  }

  /**
   * Linear index inside of a chamber for Buckeye chip processing strip
   * 'istrip'.
   *
   * Output is 1-5.
   *
   * WARNING: Use at your own risk! The supplied CSCDetId must be a strip id
   * 1-80 ME1/1b strips must be 1-64 ME1/1a strips must be 1-48 No trapping on
   * out-of-range values!
   */

  IndexType chipIndex(IndexType istrip) const { return (istrip - 1) / 16 + 1; }

  /**
   * Number of HV segments per layer in a chamber in ring ir of station is.
   *
   * Station label range 1-4, Ring label range 1-4.
   *
   * WARNING: ME1a (ir=4), ME1b(ir=1) and whole ME11 are all assumed to have the
   * same single HV segment
   */
  IndexType hvSegmentsPerLayer(IndexType is, IndexType ir) const {
    const IndexType nSinL[16] = {1, 3, 3, 1, 3, 5, 0, 0, 3, 5, 0, 0, 3, 5, 0, 0};
    return nSinL[(is - 1) * 4 + ir - 1];
  }

  /**
   * Number of Gas Gain sectors per layer in a chamber in ring ir of station is.
   *
   * Station label range 1-4, Ring label range 1-4.
   */
  IndexType sectorsPerLayer(IndexType is, IndexType ir) const {
    return chipsPerLayer(is, ir) * hvSegmentsPerLayer(is, ir);
  }

  /**
   * Linear index inside of a chamber for HV segment
   *
   * Output is 1-5.
   *
   * WARNING: Use at your own risk! The supplied CSCDetId must be chamber
   * station, ring, and wire. No trapping on out-of-range values!
   */
  IndexType hvSegmentIndex(IndexType is, IndexType ir, IndexType iwire) const;

  /**
   * Linear index for 1st Gas gain sector in ring 'ir' of station 'is' in endcap
   * 'ie'.
   *
   * Endcap label range 1-2, Station label range 1-4, Ring label range 1-3.
   *
   * WARNING:
   *   current: ME1a channels are the last 1 of the 5 chips total in each layer
   * of an ME11 chamber, and an input ir=4 is invalid and will give nonsense.
   *   upgraded:
   */
  IndexType sectorStart(IndexType ie, IndexType is, IndexType ir) const {
    // There are 36 chambers * 6 layers * 5 CFEB's * 1 HV segment = 1080
    // gas-gain sectors in ME1/1 (non-upgraded) There are 36 chambers * 6 layers
    // * 3 CFEB's * 1 HV segment = 648 gas-gain sectors in ME1/1a (upgraded)
    // There are 36*6*5*3 = 3240 gas-gain sectors in ME1/2
    // There are 36*6*4*3 = 2592 gas-gain sectors in ME1/3
    // There are 18*6*5*3 = 1620 gas-gain sectors in ME[2-4]/1
    // There are 36*6*5*5 = 5400 gas-gain sectors in ME[2-4]/2
    // Start of -z channels (CSCs 2008) is 22572 + 1 = 22573
    // Start of +z (ME42) is 45144 + 1 = 45145
    // Start of -z (ME42) is 45144 + 1 + 5400 = 50545
    // Start of +z (ME1a) is 45144 + 1 + 2*5400 = 55945
    // Start of -z (ME42) is 45144 + 1 + 2*5400 + 648 = 56593
    const IndexType nStart[32] = {1,     1081,  4321,  55945,  // ME+1/1,ME+1/2,ME+1/3,ME+1/a
                                  6913,  8533,  0,     0,      // ME+2/1,ME+2/2
                                  13933, 15553, 0,     0,      // ME+3/1,ME+3/2
                                  20953, 45145, 0,     0,      // ME+4/1,ME+4/2 (note, ME+4/2 index follows ME-4/1...)
                                  22573, 23653, 26893, 56593,  // ME-1/1,ME-1/2,ME-1/3,ME+1/a
                                  29485, 31105, 0,     0,      // ME-2/1,ME-2/2
                                  36505, 38125, 0,     0,      // ME-3/1,ME-3/2
                                  43525, 50545, 0,     0};     // ME-4/1,ME-4/2 (note, ME-4/2 index follows ME+4/2...)
    return nStart[(ie - 1) * 16 + (is - 1) * 4 + ir - 1];
  }

  /**
   * Linear index for Gas gain sector, based on CSCDetId 'id', cathode strip
   * 'istrip' and anode wire 'iwire'
   *
   * Output is 1-45144 (CSCs 2008) and 45145-55944 (ME42) and 55945-57240 (ME1a)
   *
   * WARNING: Use at your own risk!  You must input labels within hardware
   * ranges (e.g., 'id' must correspond to a specific layer 1-6). No trapping on
   * out-of-range values!
   */
  IndexType gasGainIndex(const CSCDetId &id, IndexType istrip, IndexType iwire) const {
    return gasGainIndex(id.endcap(),
                        id.station(),
                        id.ring(),
                        id.chamber(),
                        id.layer(),
                        hvSegmentIndex(id.station(), id.ring(), iwire),
                        chipIndex(istrip));
  }

  /**
   * Linear index for Gas gain sector, based on CSCDetId 'id', the HV segment#
   * and the chip#. Note: to allow method overloading, the parameters order is
   * reversed comparing to the (id,strip,wire) method
   *
   * Output is 1-45144 (CSCs 2008) and 45145-55944 (ME42) and 55945-57240 (ME1a)
   *
   * WARNING: Use at your own risk! You must input labels within hardware
   * ranges. No trapping on out-of-range values!
   */
  IndexType gasGainIndex(IndexType ihvsegment, IndexType ichip, const CSCDetId &id) const {
    return gasGainIndex(id.endcap(), id.station(), id.ring(), id.chamber(), id.layer(), ihvsegment, ichip);
  }

  /**
   * Linear index for Gas gain sector, based on the HV segment# and the chip#
   * located in layer 'il' of chamber 'ic' of ring 'ir' in station 'is' of
   * endcap 'ie'.
   *
   * Output is 1-45144 (CSCs 2008) and 45145-55944 (ME42) and 55945-57240 (ME1a)
   *
   * WARNING: Use at your own risk! You must input labels within hardware
   * ranges. No trapping on out-of-range values!
   */
  IndexType gasGainIndex(IndexType ie,
                         IndexType is,
                         IndexType ir,
                         IndexType ic,
                         IndexType il,
                         IndexType ihvsegment,
                         IndexType ichip) const {
    return sectorStart(ie, is, ir) + ((ic - 1) * 6 + il - 1) * sectorsPerLayer(is, ir) +
           (ihvsegment - 1) * chipsPerLayer(is, ir) + (ichip - 1);
  }

  /**
   *  Decode CSCDetId from various indexes and labels
   */
  CSCDetId detIdFromLayerIndex(IndexType ili) const;
  CSCDetId detIdFromChamberIndex(IndexType ici) const;
  CSCDetId detIdFromChamberIndex_OLD(IndexType ici) const;
  CSCDetId detIdFromChamberLabel(IndexType ie, IndexType icl) const;
  std::pair<CSCDetId, IndexType> detIdFromStripChannelIndex(LongIndexType ichi) const;
  std::pair<CSCDetId, IndexType> detIdFromChipIndex(IndexType ichi) const;
  GasGainTuple detIdFromGasGainIndex(IndexType igg) const;

  IndexType chamberLabelFromChamberIndex(IndexType) const;  // just for cross-checks

  /**
   * Build index used internally in online CSC conditions databases (the 'Igor
   * Index')
   *
   * This is the decimal integer ie*100000 + is*10000 + ir*1000 + ic*10 + il
   * <br> (ie=1-2, is=1-4, ir=1-4, ic=1-36, il=1-6) <br> Channels 1-16 in ME1A
   * (is=1, ir=4) are NOT reset to channels 65-80 of ME11. WARNING: This is now
   * ADOPTED to unganged ME1a channels (we expect that the online conditions DB
   * will adopt it too).
   */
  int dbIndex(const CSCDetId &id, int &channel);

private:
  void fillChamberLabel() const;  // const so it can be called in const function
                                  // detIdFromChamberIndex

  mutable std::vector<IndexType> chamberLabel;  // mutable so can be filled by fillChamberLabel
};

#endif