From d85e302143a3b2797815716866a135c0944ec783 Mon Sep 17 00:00:00 2001
From: Dave Horton <daveh@beachdognet.com>
Date: Sun, 17 Nov 2024 11:06:14 -0500
Subject: [PATCH] initial changes to change media routing during call

---
 lib/session/call-session.js | 22 +++++++++++++++++++
 lib/tasks/dial.js           | 43 +++++++++++++++++++++++++++++++------
 lib/utils/constants.json    |  5 +++++
 3 files changed, 64 insertions(+), 6 deletions(-)

diff --git a/lib/session/call-session.js b/lib/session/call-session.js
index 1785eaa4..503f28dd 100644
--- a/lib/session/call-session.js
+++ b/lib/session/call-session.js
@@ -1589,6 +1589,18 @@ Duration=${duration} `
     this.logger.info({response}, '_lccBoostAudioSignal: response from freeswitch');
   }
 
+  async _lccMediaPath(opts, callSid) {
+    const {type} = opts;
+
+    // only valid in a Dial verb
+    const task = this.currentTask;
+    if (!task || task.name !== TaskName.Dial) {
+      return this.logger.info('CallSession:_lccMediaPath - invalid command since we are not in a dial verb');
+    }
+    task.updateMediaPath(type)
+      .catch((err) => this.logger.error(err, 'CallSession:_lccMediaPath'));
+  }
+
   _lccToolOutput(tool_call_id, opts, callSid) {
     // only valid if we are in an LLM verb
     const task = this.currentTask;
@@ -1672,6 +1684,9 @@ Duration=${duration} `
     else if (opts.boostAudioSignal) {
       return this._lccBoostAudioSignal(opts, callSid);
     }
+    else if (opts.media_path) {
+      return this._lccMediaPath(opts.media_path, callSid);
+    }
     else if (opts.llm_tool_output) {
       return this._lccToolOutput(opts.tool_call_id, opts.llm_tool_output, callSid);
     }
@@ -1975,6 +1990,13 @@ Duration=${duration} `
           });
         break;
 
+      case 'media-path':
+        this._lccMediaPath(data, call_sid)
+          .catch((err) => {
+            this.logger.info({err, data}, 'CallSession:_onCommand - error setting media path');
+          });
+        break;
+
       case 'llm:tool-output':
         this._lccToolOutput(tool_call_id, data, call_sid);
         break;
diff --git a/lib/tasks/dial.js b/lib/tasks/dial.js
index 9356e5ca..c9e93c18 100644
--- a/lib/tasks/dial.js
+++ b/lib/tasks/dial.js
@@ -6,6 +6,7 @@ const {
   TaskName,
   TaskPreconditions,
   MAX_SIMRINGS,
+  MediaPath,
   KillReason
 } = require('../utils/constants');
 const assert = require('assert');
@@ -108,6 +109,7 @@ class TaskDial extends Task {
     this.proxy = this.data.proxy;
     this.tag = this.data.tag;
     this.boostAudioSignal = this.data.boostAudioSignal;
+    this._mediaPath = MediaPath.FullMedia;
 
     if (this.dtmfHook) {
       const {parentDtmfCollector, childDtmfCollector} = parseDtmfOptions(logger, this.data.dtmfCapture || {});
@@ -167,7 +169,7 @@ class TaskDial extends Task {
   }
 
   get shouldExitMediaPathEntirely() {
-    return this.canReleaseMedia && this.data.exitMediaPath;
+    return this.data.exitMediaPath;
   }
 
   get summary() {
@@ -307,7 +309,7 @@ class TaskDial extends Task {
       if (!cs.callGone && this.epOther) {
 
         /* if we can release the media back to the SBC, do so now */
-        if (this.canReleaseMedia) this._releaseMedia(cs, this.sd);
+        if (this.canReleaseMedia) this._releaseMedia(cs, this.sd, this.shouldExitMediaPathEntirely);
         else this.epOther.bridge(this.ep);
       }
     } catch (err) {
@@ -756,7 +758,7 @@ class TaskDial extends Task {
             // Offhold, time to release media
             const newSdp = await this.ep.modify(req.body);
             await res.send(200, {body: newSdp});
-            await this._releaseMedia(this.cs, this.sd);
+            await this._releaseMedia(this.cs, this.sd, this.shouldExitMediaPathEntirely);
             this.isOutgoingLegHold = false;
           } else {
             this.logger.debug('Dial: _onReinvite receive unhold Request, update media server');
@@ -865,7 +867,7 @@ class TaskDial extends Task {
     }
 
     /* if we can release the media back to the SBC, do so now */
-    if (this.canReleaseMedia) setTimeout(this._releaseMedia.bind(this, cs, sd), 200);
+    if (this.canReleaseMedia) setTimeout(this._releaseMedia.bind(this, cs, sd, this.shouldExitMediaPathEntirely), 200);
   }
 
   _bridgeEarlyMedia(sd) {
@@ -877,12 +879,40 @@ class TaskDial extends Task {
     }
   }
 
+  /* public api */
+  async updateMediaPath(type) {
+    switch (type) {
+      case 'no-media':
+        assert(this._mediaPath !== MediaPath.NoMedia, 'updateMediaPath: already no-media');
+        await this._releaseMedia(this.cs, this.sd, true);
+        this._mediaPath = MediaPath.NoMedia;
+        break;
+      case 'partial-media':
+        assert(this._mediaPath !== MediaPath.PartialMedia, 'updateMediaPath: already partial-media');
+        if (this._mediaPath === MediaPath.FullMedia) {
+          await this._releaseMedia(this.cs, this.sd, false);
+        }
+        else {
+          await this.reAnchorMedia(this.cs, this.sd);
+        }
+        this._mediaPath = MediaPath.PartialMedia;
+        break;
+      case 'full-media':
+        assert(this._mediaPath !== MediaPath.FullMedia, 'updateMediaPath: already full-media');
+        await this.reAnchorMedia(this.cs, this.sd);
+        this._mediaPath = MediaPath.FullMedia;
+        break;
+      default:
+        assert(false, `updateMediaPath: invalid type ${type}`);
+    }
+  }
+
   /**
    * Release the media from freeswitch
    * @param {*} cs
    * @param {*} sd
    */
-  async _releaseMedia(cs, sd) {
+  async _releaseMedia(cs, sd, releaseEntirely = false) {
     assert(cs.ep && sd.ep);
 
     try {
@@ -893,6 +923,7 @@ class TaskDial extends Task {
       await cs.releaseMediaToSBC(bLegSdp, this.shouldExitMediaPathEntirely);
       this.epOther = null;
       this.logger.info('Dial:_releaseMedia - successfully released media from freewitch');
+      this._mediaPath = this.shouldExitMediaPathEntirely ? MediaPath.NoMedia : MediaPath.PartialMedia;
     } catch (err) {
       this.logger.info({err}, 'Dial:_releaseMedia error');
     }
@@ -926,7 +957,7 @@ class TaskDial extends Task {
           // Offhold, time to release media
           const newSdp = await this.epOther.modify(req.body);
           await res.send(200, {body: newSdp});
-          await this._releaseMedia(this.cs, this.sd);
+          await this._releaseMedia(this.cs, this.sd, this.shouldExitMediaPathEntirely);
           isHandled = true;
         }
         this.isIncomingLegHold = false;
diff --git a/lib/utils/constants.json b/lib/utils/constants.json
index 996e6819..090a7285 100644
--- a/lib/utils/constants.json
+++ b/lib/utils/constants.json
@@ -221,6 +221,11 @@
     "ToneTimeout": "amd_tone_timeout",
     "Stopped": "amd_stopped"
   },
+  "MediaPath": {
+    "NoMedia": "no-media",
+    "PartialMedia": "partial-media",
+    "FullMedia": "full-media"
+  },
   "MAX_SIMRINGS": 10,
   "BONG_TONE": "tone_stream://v=-7;%(100,0,941.0,1477.0);v=-7;>=2;+=.1;%(1400,0,350,440)",
   "FS_UUID_SET_NAME": "fsUUIDs"