/******************************************************************************
 *
 *  Copyright 2009-2012 Broadcom Corporation
 *
 *  Licensed under the Apache License, Version 2.0 (the "License");
 *  you may not use this file except in compliance with the License.
 *  You may obtain a copy of the License at:
 *
 *  http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 *
 ******************************************************************************/

/******************************************************************************
 *
 *  This is the implementation file for the MCAP Control Channel Action
 *  Functions.
 *
 ******************************************************************************/
#include <log/log.h>
#include <string.h>
#include "bt_common.h"
#include "bt_target.h"
#include "bt_utils.h"
#include "btm_api.h"
#include "mca_api.h"
#include "mca_defs.h"
#include "mca_int.h"
#include "osi/include/osi.h"

#include "btu.h"

/*****************************************************************************
 * constants
 ****************************************************************************/
/*******************************************************************************
 *
 * Function         mca_ccb_rsp_tout
 *
 * Description      This function processes the response timeout.
 *
 * Returns          void.
 *
 ******************************************************************************/
void mca_ccb_rsp_tout(tMCA_CCB* p_ccb, UNUSED_ATTR tMCA_CCB_EVT* p_data) {
  tMCA_CTRL evt_data;

  mca_ccb_report_event(p_ccb, MCA_RSP_TOUT_IND_EVT, &evt_data);
}

/*******************************************************************************
 *
 * Function         mca_ccb_report_event
 *
 * Description      This function reports the given event.
 *
 * Returns          void.
 *
 ******************************************************************************/
void mca_ccb_report_event(tMCA_CCB* p_ccb, uint8_t event, tMCA_CTRL* p_data) {
  if (p_ccb && p_ccb->p_rcb && p_ccb->p_rcb->p_cback)
    (*p_ccb->p_rcb->p_cback)(mca_rcb_to_handle(p_ccb->p_rcb),
                             mca_ccb_to_hdl(p_ccb), event, p_data);
}

/*******************************************************************************
 *
 * Function         mca_ccb_free_msg
 *
 * Description      This function frees the received message.
 *
 * Returns          void.
 *
 ******************************************************************************/
void mca_ccb_free_msg(UNUSED_ATTR tMCA_CCB* p_ccb, tMCA_CCB_EVT* p_data) {
  osi_free(p_data);
}

/*******************************************************************************
 *
 * Function         mca_ccb_snd_req
 *
 * Description      This function builds a request and sends it to the peer.
 *
 * Returns          void.
 *
 ******************************************************************************/
void mca_ccb_snd_req(tMCA_CCB* p_ccb, tMCA_CCB_EVT* p_data) {
  tMCA_CCB_MSG* p_msg = (tMCA_CCB_MSG*)p_data;
  uint8_t *p, *p_start;
  bool is_abort = false;
  tMCA_DCB* p_dcb;

  MCA_TRACE_DEBUG("mca_ccb_snd_req cong=%d req=%d", p_ccb->cong,
                  p_msg->op_code);
  /* check for abort request */
  if ((p_ccb->status == MCA_CCB_STAT_PENDING) &&
      (p_msg->op_code == MCA_OP_MDL_ABORT_REQ)) {
    p_dcb = mca_dcb_by_hdl(p_ccb->p_tx_req->dcb_idx);
    /* the Abort API does not have the associated mdl_id.
     * Get the mdl_id in dcb to compose the request */
    p_msg->mdl_id = p_dcb->mdl_id;
    mca_dcb_event(p_dcb, MCA_DCB_API_CLOSE_EVT, NULL);
    osi_free_and_reset((void**)&p_ccb->p_tx_req);
    p_ccb->status = MCA_CCB_STAT_NORM;
    is_abort = true;
  }

  /* no pending outgoing messages or it's an abort request for a pending data
   * channel */
  if ((!p_ccb->p_tx_req) || is_abort) {
    p_ccb->p_tx_req = p_msg;
    if (!p_ccb->cong) {
      BT_HDR* p_pkt = (BT_HDR*)osi_malloc(MCA_CTRL_MTU + sizeof(BT_HDR));

      p_pkt->offset = L2CAP_MIN_OFFSET;
      p = p_start = (uint8_t*)(p_pkt + 1) + L2CAP_MIN_OFFSET;
      *p++ = p_msg->op_code;
      UINT16_TO_BE_STREAM(p, p_msg->mdl_id);
      if (p_msg->op_code == MCA_OP_MDL_CREATE_REQ) {
        *p++ = p_msg->mdep_id;
        *p++ = p_msg->param;
      }
      p_msg->hdr.layer_specific = true; /* mark this message as sent */
      p_pkt->len = p - p_start;
      L2CA_DataWrite(p_ccb->lcid, p_pkt);
      uint64_t interval_ms = p_ccb->p_rcb->reg.rsp_tout * 1000;
      alarm_set_on_mloop(p_ccb->mca_ccb_timer, interval_ms,
                         mca_ccb_timer_timeout, p_ccb);
    }
    /* else the L2CAP channel is congested. keep the message to be sent later */
  } else {
    MCA_TRACE_WARNING("dropping api req");
    osi_free(p_data);
  }
}

/*******************************************************************************
 *
 * Function         mca_ccb_snd_rsp
 *
 * Description      This function builds a response and sends it to
 *                  the peer.
 *
 * Returns          void.
 *
 ******************************************************************************/
void mca_ccb_snd_rsp(tMCA_CCB* p_ccb, tMCA_CCB_EVT* p_data) {
  tMCA_CCB_MSG* p_msg = (tMCA_CCB_MSG*)p_data;
  uint8_t *p, *p_start;
  BT_HDR* p_pkt = (BT_HDR*)osi_malloc(MCA_CTRL_MTU + sizeof(BT_HDR));

  MCA_TRACE_DEBUG("%s cong=%d req=%d", __func__, p_ccb->cong, p_msg->op_code);
  /* assume that API functions verified the parameters */

  p_pkt->offset = L2CAP_MIN_OFFSET;
  p = p_start = (uint8_t*)(p_pkt + 1) + L2CAP_MIN_OFFSET;
  *p++ = p_msg->op_code;
  *p++ = p_msg->rsp_code;
  UINT16_TO_BE_STREAM(p, p_msg->mdl_id);
  // Only add extra parameters for MCA_RSP_SUCCESS message
  if (p_msg->rsp_code == MCA_RSP_SUCCESS) {
    // Append MDL configuration parameters
    if (p_msg->op_code == MCA_OP_MDL_CREATE_RSP) {
      *p++ = p_msg->param;
    }
    // Check MDL
    if (p_msg->op_code == MCA_OP_MDL_CREATE_RSP ||
        p_msg->op_code == MCA_OP_MDL_RECONNECT_RSP) {
      mca_dcb_by_hdl(p_msg->dcb_idx);
      BTM_SetSecurityLevel(false, "", BTM_SEC_SERVICE_MCAP_DATA,
                           p_ccb->sec_mask, p_ccb->p_rcb->reg.data_psm,
                           BTM_SEC_PROTO_MCA, p_msg->dcb_idx);
      p_ccb->status = MCA_CCB_STAT_PENDING;
      /* set p_tx_req to block API_REQ/API_RSP before DL is up */
      osi_free_and_reset((void**)&p_ccb->p_tx_req);
      p_ccb->p_tx_req = p_ccb->p_rx_msg;
      p_ccb->p_rx_msg = NULL;
      p_ccb->p_tx_req->dcb_idx = p_msg->dcb_idx;
    }
  }

  osi_free_and_reset((void**)&p_ccb->p_rx_msg);
  p_pkt->len = p - p_start;
  L2CA_DataWrite(p_ccb->lcid, p_pkt);
}

/*******************************************************************************
 *
 * Function         mca_ccb_do_disconn
 *
 * Description      This function closes a control channel.
 *
 * Returns          void.
 *
 ******************************************************************************/
void mca_ccb_do_disconn(tMCA_CCB* p_ccb, UNUSED_ATTR tMCA_CCB_EVT* p_data) {
  mca_dcb_close_by_mdl_id(p_ccb, MCA_ALL_MDL_ID);
  L2CA_DisconnectReq(p_ccb->lcid);
}

/*******************************************************************************
 *
 * Function         mca_ccb_cong
 *
 * Description      This function sets the congestion state for the CCB.
 *
 * Returns          void.
 *
 ******************************************************************************/
void mca_ccb_cong(tMCA_CCB* p_ccb, tMCA_CCB_EVT* p_data) {
  MCA_TRACE_DEBUG("mca_ccb_cong cong=%d/%d", p_ccb->cong, p_data->llcong);
  p_ccb->cong = p_data->llcong;
  if (!p_ccb->cong) {
    /* if there's a held packet, send it now */
    if (p_ccb->p_tx_req && !p_ccb->p_tx_req->hdr.layer_specific) {
      p_data = (tMCA_CCB_EVT*)p_ccb->p_tx_req;
      p_ccb->p_tx_req = NULL;
      mca_ccb_snd_req(p_ccb, p_data);
    }
  }
}

/*******************************************************************************
 *
 * Function         mca_ccb_hdl_req
 *
 * Description      This function is called when a MCAP request is received from
 *                  the peer. It calls the application callback function to
 *                  report the event.
 *
 * Returns          void.
 *
 ******************************************************************************/
void mca_ccb_hdl_req(tMCA_CCB* p_ccb, tMCA_CCB_EVT* p_data) {
  BT_HDR* p_pkt = &p_data->hdr;
  uint8_t *p, *p_start;
  tMCA_DCB* p_dcb;
  tMCA_CTRL evt_data;
  tMCA_CCB_MSG* p_rx_msg = NULL;
  uint8_t reject_code = MCA_RSP_NO_RESOURCE;
  bool send_rsp = false;
  bool check_req = false;
  uint8_t reject_opcode;

  MCA_TRACE_DEBUG("mca_ccb_hdl_req status:%d", p_ccb->status);
  p_rx_msg = (tMCA_CCB_MSG*)p_pkt;
  p = (uint8_t*)(p_pkt + 1) + p_pkt->offset;
  evt_data.hdr.op_code = *p++;
  reject_opcode = evt_data.hdr.op_code + 1;

  if (p_pkt->len >= 3) {
    BE_STREAM_TO_UINT16(evt_data.hdr.mdl_id, p);
  } else {
    android_errorWriteLog(0x534e4554, "110791536");
    evt_data.hdr.mdl_id = 0;
  }

  MCA_TRACE_DEBUG("received mdl id: %d ", evt_data.hdr.mdl_id);
  if (p_ccb->status == MCA_CCB_STAT_PENDING) {
    MCA_TRACE_DEBUG("received req inpending state");
    /* allow abort in pending state */
    if ((p_ccb->status == MCA_CCB_STAT_PENDING) &&
        (evt_data.hdr.op_code == MCA_OP_MDL_ABORT_REQ)) {
      reject_code = MCA_RSP_SUCCESS;
      send_rsp = true;
      /* clear the pending status */
      p_ccb->status = MCA_CCB_STAT_NORM;
      if (p_ccb->p_tx_req &&
          ((p_dcb = mca_dcb_by_hdl(p_ccb->p_tx_req->dcb_idx)) != NULL)) {
        mca_dcb_dealloc(p_dcb, NULL);
        osi_free_and_reset((void**)&p_ccb->p_tx_req);
      }
    } else
      reject_code = MCA_RSP_BAD_OP;
  } else if (p_ccb->p_rx_msg) {
    MCA_TRACE_DEBUG("still handling prev req");
    /* still holding previous message, reject this new one ?? */

  } else if (p_ccb->p_tx_req) {
    MCA_TRACE_DEBUG("still waiting for a response ctrl_vpsm:0x%x",
                    p_ccb->ctrl_vpsm);
    /* sent a request; waiting for response */
    if (p_ccb->ctrl_vpsm == 0) {
      MCA_TRACE_DEBUG("local is ACP. accept the cmd from INT");
      /* local is acceptor, need to handle the request */
      check_req = true;
      reject_code = MCA_RSP_SUCCESS;
      /* drop the previous request */
      if ((p_ccb->p_tx_req->op_code == MCA_OP_MDL_CREATE_REQ) &&
          ((p_dcb = mca_dcb_by_hdl(p_ccb->p_tx_req->dcb_idx)) != NULL)) {
        mca_dcb_dealloc(p_dcb, NULL);
      }
      osi_free_and_reset((void**)&p_ccb->p_tx_req);
      mca_stop_timer(p_ccb);
    } else {
      /*  local is initiator, ignore the req */
      osi_free(p_pkt);
      return;
    }
  } else if (p_pkt->layer_specific != MCA_RSP_SUCCESS) {
    reject_code = (uint8_t)p_pkt->layer_specific;
    if (((evt_data.hdr.op_code >= MCA_NUM_STANDARD_OPCODE) &&
         (evt_data.hdr.op_code < MCA_FIRST_SYNC_OP)) ||
        (evt_data.hdr.op_code > MCA_LAST_SYNC_OP)) {
      /* invalid op code */
      reject_opcode = MCA_OP_ERROR_RSP;
      evt_data.hdr.mdl_id = 0;
    }
  } else {
    check_req = true;
    reject_code = MCA_RSP_SUCCESS;
  }

  if (check_req) {
    if (reject_code == MCA_RSP_SUCCESS) {
      reject_code = MCA_RSP_BAD_MDL;
      if (MCA_IS_VALID_MDL_ID(evt_data.hdr.mdl_id) ||
          ((evt_data.hdr.mdl_id == MCA_ALL_MDL_ID) &&
           (evt_data.hdr.op_code == MCA_OP_MDL_DELETE_REQ))) {
        reject_code = MCA_RSP_SUCCESS;
        /* mdl_id is valid according to the spec */
        switch (evt_data.hdr.op_code) {
          case MCA_OP_MDL_CREATE_REQ:
            evt_data.create_ind.dep_id = *p++;
            evt_data.create_ind.cfg = *p++;
            p_rx_msg->mdep_id = evt_data.create_ind.dep_id;
            if (!mca_is_valid_dep_id(p_ccb->p_rcb, p_rx_msg->mdep_id)) {
              MCA_TRACE_ERROR("%s: Invalid local MDEP ID %d", __func__,
                              p_rx_msg->mdep_id);
              reject_code = MCA_RSP_BAD_MDEP;
            } else if (mca_ccb_uses_mdl_id(p_ccb, evt_data.hdr.mdl_id)) {
              MCA_TRACE_DEBUG("the mdl_id is currently used in the CL(create)");
              mca_dcb_close_by_mdl_id(p_ccb, evt_data.hdr.mdl_id);
            } else {
              /* check if this dep still have MDL available */
              if (mca_dep_free_mdl(p_ccb, evt_data.create_ind.dep_id) == 0) {
                MCA_TRACE_ERROR("%s: MAX_MDL is used by MDEP %d", __func__,
                                evt_data.create_ind.dep_id);
                reject_code = MCA_RSP_MDEP_BUSY;
              }
            }
            break;

          case MCA_OP_MDL_RECONNECT_REQ:
            if (mca_ccb_uses_mdl_id(p_ccb, evt_data.hdr.mdl_id)) {
              MCA_TRACE_ERROR("%s: MDL_ID %d busy, in CL(reconn)", __func__,
                              evt_data.hdr.mdl_id);
              reject_code = MCA_RSP_MDL_BUSY;
            }
            break;

          case MCA_OP_MDL_ABORT_REQ:
            reject_code = MCA_RSP_BAD_OP;
            break;

          case MCA_OP_MDL_DELETE_REQ:
            /* delete the associated mdl */
            mca_dcb_close_by_mdl_id(p_ccb, evt_data.hdr.mdl_id);
            send_rsp = true;
            break;
        }
      }
    }
  }

  if (((reject_code != MCA_RSP_SUCCESS) &&
       (evt_data.hdr.op_code != MCA_OP_SYNC_INFO_IND)) ||
      send_rsp) {
    BT_HDR* p_buf = (BT_HDR*)osi_malloc(MCA_CTRL_MTU + sizeof(BT_HDR));
    p_buf->offset = L2CAP_MIN_OFFSET;
    p = p_start = (uint8_t*)(p_buf + 1) + L2CAP_MIN_OFFSET;
    *p++ = reject_opcode;
    *p++ = reject_code;
    bool valid_response = true;
    switch (reject_opcode) {
      // Fill in the rest of standard opcode response packet with mdl_id
      case MCA_OP_ERROR_RSP:
      case MCA_OP_MDL_CREATE_RSP:
      case MCA_OP_MDL_RECONNECT_RSP:
      case MCA_OP_MDL_ABORT_RSP:
      case MCA_OP_MDL_DELETE_RSP:
        UINT16_TO_BE_STREAM(p, evt_data.hdr.mdl_id);
        break;
      // Fill in the rest of clock sync opcode response packet with 0
      case MCA_OP_SYNC_CAP_RSP:
        // Page 37/58 MCAP V1.0 Spec: Total length (9) - 2 = 7
        memset(p, 0, 7);
        p += 7;
        break;
      case MCA_OP_SYNC_SET_RSP:
        // Page 39/58 MCAP V1.0 Spec: Total length (16) - 2 = 14
        memset(p, 0, 14);
        p += 14;
        break;
      default:
        MCA_TRACE_ERROR("%s: reject_opcode 0x%02x not recognized", __func__,
                        reject_opcode);
        valid_response = false;
        break;
    }
    if (valid_response) {
      p_buf->len = p - p_start;
      MCA_TRACE_ERROR("%s: reject_opcode=0x%02x, reject_code=0x%02x, length=%d",
                      __func__, reject_opcode, reject_code, p_buf->len);
      L2CA_DataWrite(p_ccb->lcid, p_buf);
    } else {
      osi_free(p_buf);
    }
  }

  if (reject_code == MCA_RSP_SUCCESS) {
    /* use the received GKI buffer to store information to double check response
     * API */
    p_rx_msg->op_code = evt_data.hdr.op_code;
    p_rx_msg->mdl_id = evt_data.hdr.mdl_id;
    p_ccb->p_rx_msg = p_rx_msg;
    if (send_rsp) {
      osi_free(p_pkt);
      p_ccb->p_rx_msg = NULL;
    }
    mca_ccb_report_event(p_ccb, evt_data.hdr.op_code, &evt_data);
  } else
    osi_free(p_pkt);
}

/*******************************************************************************
 *
 * Function         mca_ccb_hdl_rsp
 *
 * Description      This function is called when a MCAP response is received
 *                  from the peer.  It calls the application callback function
 *                  with the results.
 *
 * Returns          void.
 *
 ******************************************************************************/
void mca_ccb_hdl_rsp(tMCA_CCB* p_ccb, tMCA_CCB_EVT* p_data) {
  BT_HDR* p_pkt = &p_data->hdr;
  uint8_t* p;
  tMCA_CTRL evt_data;
  bool chk_mdl = false;
  tMCA_DCB* p_dcb;
  tMCA_RESULT result = MCA_BAD_HANDLE;
  tMCA_TC_TBL* p_tbl;

  if (p_pkt->len < sizeof(evt_data.hdr.op_code) +
                       sizeof(evt_data.rsp.rsp_code) +
                       sizeof(evt_data.hdr.mdl_id)) {
    android_errorWriteLog(0x534e4554, "116319076");
    MCA_TRACE_ERROR("%s: Response packet is too short", __func__);
  } else if (p_ccb->p_tx_req) {
    /* verify that the received response matches the sent request */
    p = (uint8_t*)(p_pkt + 1) + p_pkt->offset;
    evt_data.hdr.op_code = *p++;
    if ((evt_data.hdr.op_code == MCA_OP_MDL_CREATE_RSP) &&
        (p_pkt->len <
         sizeof(evt_data.hdr.op_code) + sizeof(evt_data.rsp.rsp_code) +
             sizeof(evt_data.hdr.mdl_id) + sizeof(evt_data.create_cfm.cfg))) {
      android_errorWriteLog(0x534e4554, "116319076");
      MCA_TRACE_ERROR("%s: MDL Create Response packet is too short", __func__);
    } else if ((evt_data.hdr.op_code == 0) ||
               ((p_ccb->p_tx_req->op_code + 1) == evt_data.hdr.op_code)) {
      evt_data.rsp.rsp_code = *p++;
      mca_stop_timer(p_ccb);
      BE_STREAM_TO_UINT16(evt_data.hdr.mdl_id, p);
      if (evt_data.hdr.op_code == MCA_OP_MDL_CREATE_RSP) {
        evt_data.create_cfm.cfg = *p++;
        chk_mdl = true;
      } else if (evt_data.hdr.op_code == MCA_OP_MDL_RECONNECT_RSP)
        chk_mdl = true;

      if (chk_mdl) {
        p_dcb = mca_dcb_by_hdl(p_ccb->p_tx_req->dcb_idx);
        if (evt_data.rsp.rsp_code == MCA_RSP_SUCCESS) {
          if (evt_data.hdr.mdl_id != p_dcb->mdl_id) {
            MCA_TRACE_ERROR("peer's mdl_id=%d != our mdl_id=%d",
                            evt_data.hdr.mdl_id, p_dcb->mdl_id);
            /* change the response code to be an error */
            if (evt_data.rsp.rsp_code == MCA_RSP_SUCCESS) {
              evt_data.rsp.rsp_code = MCA_RSP_BAD_MDL;
              /* send Abort */
              p_ccb->status = MCA_CCB_STAT_PENDING;
              MCA_Abort(mca_ccb_to_hdl(p_ccb));
            }
          } else if (p_dcb->p_chnl_cfg) {
            /* the data channel configuration is known. Proceed with data
             * channel initiation */
            BTM_SetSecurityLevel(true, "", BTM_SEC_SERVICE_MCAP_DATA,
                                 p_ccb->sec_mask, p_ccb->data_vpsm,
                                 BTM_SEC_PROTO_MCA, p_ccb->p_tx_req->dcb_idx);
            p_dcb->lcid = mca_l2c_open_req(p_ccb->peer_addr, p_ccb->data_vpsm,
                                           p_dcb->p_chnl_cfg);
            if (p_dcb->lcid) {
              p_tbl = mca_tc_tbl_dalloc(p_dcb);
              if (p_tbl) {
                p_tbl->state = MCA_TC_ST_CONN;
                p_ccb->status = MCA_CCB_STAT_PENDING;
                result = MCA_SUCCESS;
              }
            }
          } else {
            /* mark this MCL as pending and wait for MCA_DataChnlCfg */
            p_ccb->status = MCA_CCB_STAT_PENDING;
            result = MCA_SUCCESS;
          }
        }

        if (result != MCA_SUCCESS && p_dcb) {
          mca_dcb_dealloc(p_dcb, NULL);
        }
      } /* end of chk_mdl */

      if (p_ccb->status != MCA_CCB_STAT_PENDING)
        osi_free_and_reset((void**)&p_ccb->p_tx_req);
      mca_ccb_report_event(p_ccb, evt_data.hdr.op_code, &evt_data);
    }
    /* else a bad response is received */
  } else {
    /* not expecting any response. drop it */
    MCA_TRACE_WARNING("dropping received rsp (not expecting a response)");
  }
  osi_free(p_data);
}

/*******************************************************************************
 *
 * Function         mca_ccb_ll_open
 *
 * Description      This function is called to report MCA_CONNECT_IND_EVT event.
 *                  It also clears the congestion flag (ccb.cong).
 *
 * Returns          void.
 *
 ******************************************************************************/
void mca_ccb_ll_open(tMCA_CCB* p_ccb, tMCA_CCB_EVT* p_data) {
  tMCA_CTRL evt_data;
  p_ccb->cong = false;
  evt_data.connect_ind.mtu = p_data->open.peer_mtu;
  evt_data.connect_ind.bd_addr = p_ccb->peer_addr;
  mca_ccb_report_event(p_ccb, MCA_CONNECT_IND_EVT, &evt_data);
}

/*******************************************************************************
 *
 * Function         mca_ccb_dl_open
 *
 * Description      This function is called when data channel is open. It clears
 *                  p_tx_req to allow other message exchage on this CL.
 *
 * Returns          void.
 *
 ******************************************************************************/
void mca_ccb_dl_open(tMCA_CCB* p_ccb, UNUSED_ATTR tMCA_CCB_EVT* p_data) {
  osi_free_and_reset((void**)&p_ccb->p_tx_req);
  osi_free_and_reset((void**)&p_ccb->p_rx_msg);
  p_ccb->status = MCA_CCB_STAT_NORM;
}