npctalk: add support for generic CONDITION trials

Add a new type of trial, "CONDITION" which always succeeds or fails based
on the value of a condition object.

data/json/npcs/TALK_TEST.json

@@ -319,6 +319,28 @@
       }
     ]
   },
+  {
+    "type": "talk_topic",
+    "id": "TALK_TEST_TRUE_FALSE_CONDITIONAL",
+    "dynamic_line": "This is a test conversation that shouldn't appear in the game.",
+    "responses": [
+      { "text": "This is a basic test response.", "topic": "TALK_DONE" },
+      {
+        "truefalsetext": {
+          "condition": { "u_has_cash": 500 },
+          "true": "This is a true/false true response.",
+          "false": "This is a true/false false response."
+        },
+        "topic": "TALK_DONE"
+      },
+      {
+        "text": "This is a conditional trial response.",
+        "trial": { "type": "CONDITION", "condition": { "u_has_cash": 500 } },
+        "success": { "topic": "TALK_TEST_TRUE_CONDITION_NEXT" },
+        "failure": { "topic": "TALK_TEST_FALSE_CONDITION_NEXT" }
+      }
+    ]
+  },
   {
     "type": "talk_topic",
     "id": "TALK_TEST_EFFECTS",

doc/NPCs.md

@@ -396,10 +396,13 @@ The player will have one response text if a condition is true, and another if it
 Will be shown to the user, no further meaning.
 
 ### trial
-Optional, if not defined, "NONE" is used. Otherwise one of "NONE", "LIE", "PERSUADE" or "INTIMIDATE". If "NONE" is used, the `failure` object is not read, otherwise it's mandatory.
-The `difficulty` is only required if type is not "NONE" and specifies the success chance in percent (it is however modified by various things like mutations).
+Optional, if not defined, "NONE" is used. Otherwise one of "NONE", "LIE", "PERSUADE" "INTIMIDATE", or "CONDITION". If "NONE" is used, the `failure` object is not read, otherwise it's mandatory.
 
-An optional `mod` array takes any of the following modifiers and increases the difficulty by the NPC's opinion of your character or personality trait for that modifier multiplied by the value: "ANGER", "FEAR", "TRUST", "VALUE", "AGRESSION", "ALTRUISM", "BRAVERY", "COLLECTOR". The special "POS_FEAR" modifier treats NPC's fear of your character below 0 as though it were 0.
+The `difficulty` is only required if type is not "NONE" or "CONDITION" and specifies the success chance in percent (it is however modified by various things like mutations).  Higher difficulties are easier to pass.
+
+An optional `mod` array takes any of the following modifiers and increases the difficulty by the NPC's opinion of your character or personality trait for that modifier multiplied by the value: "ANGER", "FEAR", "TRUST", "VALUE", "AGRESSION", "ALTRUISM", "BRAVERY", "COLLECTOR". The special "POS_FEAR" modifier treats NPC's fear of your character below 0 as though it were 0.  The special "TOTAL" modifier sums all previous modifiers and then multiplies the result by its value and is used when setting the owed value.
+
+"CONDITION" trials take a mandatory `condition` instead of `difficulty`.  The `success` object is chosen if the `condition` is true and the `failure` is chosen otherwise.
 
 ### success and failure
 Both objects have the same structure. `topic` defines which topic the dialogue will switch to. `opinion` is optional, if given it defines how the opinion of the NPC will change. The given values are *added* to the opinion of the NPC, they are all optional and default to 0. `effect` is a function that is executed after choosing the response, see below.
@@ -559,8 +562,8 @@ The NPC will train your character in a skill or martial art.
 #### companion_mission: role_string
 The NPC will offer you a list of missions for your allied NPCs, depending on the NPC's role.
 
-#### u_add_effect: effect_string, (optional duration: duration_string)
-#### npc_add_effect: effect_string, (optional duration: duration_string)
+#### u_add_effect: effect_string, duration_string: "duration"
+#### npc_add_effect: effect_string, duration_string: "duration"
 Your character or the NPC will gain the effect for `duration_string` turns.  `duration_string` can also be "PERMANENT" to indicate a permanent duration, or duration can be specified as an integer.
 
 #### u_add_trait: trait_string

src/dialogue.h

@@ -28,6 +28,7 @@ enum talk_trial_type : unsigned char {
     TALK_TRIAL_LIE, // Straight up lying
     TALK_TRIAL_PERSUADE, // Convince them
     TALK_TRIAL_INTIMIDATE, // Physical intimidation
+    TALK_TRIAL_CONDITION, // Some other condition
     NUM_TALK_TRIALS
 };
 
@@ -52,6 +53,7 @@ using trial_mod = std::pair<std::string, int>;
 struct talk_trial {
     talk_trial_type type = TALK_TRIAL_NONE;
     int difficulty = 0;
+    std::function<bool( const dialogue & )> condition;
 
     int calc_chance( const dialogue &d ) const;
     /**

src/npctalk.cpp

@@ -108,7 +108,7 @@ void bulk_trade_accept( npc &, const itype_id &it );
 const std::string &talk_trial::name() const
 {
     static const std::array<std::string, NUM_TALK_TRIALS> texts = { {
-            "", _( "LIE" ), _( "PERSUADE" ), _( "INTIMIDATE" )
+            "", _( "LIE" ), _( "PERSUADE" ), _( "INTIMIDATE" ), ""
         }
     };
     if( static_cast<size_t>( type ) >= texts.size() ) {
@@ -1329,7 +1329,6 @@ int talk_trial::calc_chance( const dialogue &d ) const
     npc &p = *d.beta;
     int chance = difficulty;
     switch( type ) {
-        case TALK_TRIAL_NONE:
         case NUM_TALK_TRIALS:
             dbg( D_ERROR ) << "called calc_chance with invalid talk_trial value: " << type;
             break;
@@ -1378,6 +1377,12 @@ int talk_trial::calc_chance( const dialogue &d ) const
                 chance += 20;
             }
             break;
+        case TALK_TRIAL_NONE:
+            chance = 100;
+            break;
+         case TALK_TRIAL_CONDITION:
+            chance = condition( d ) ? 100 : 0;
+            break;
     }
     for( auto this_mod: modifiers ) {
         chance += parse_mod( d, this_mod.first, this_mod.second );
@@ -1668,18 +1673,16 @@ talk_data talk_response::create_option_line( const dialogue &d, const char lette
 {
     std::string ftext;
     text = truefalse_condition( d ) ? truetext : falsetext;
-    if( trial != TALK_TRIAL_NONE ) { // dialogue w/ a % chance to work
-        ftext = string_format( pgettext( "talk option", "%1$c: [%2$s %3$d%%] %4$s" ),
-                               letter,                         // option letter
-                               trial.name(),     // trial type
-                               trial.calc_chance( d ), // trial % chance
-                               text                // response
-                             );
-    } else { // regular dialogue
-        ftext = string_format( pgettext( "talk option", "%1$c: %2$s" ),
-                               letter,          // option letter
-                               text // response
-                             );
+     // dialogue w/ a % chance to work
+    if( trial.type == TALK_TRIAL_NONE || trial.type == TALK_TRIAL_CONDITION ) {
+        // regular dialogue
+        //~ %1$c is an option letter and shouldn't be translated, %2$s is translated response text
+        ftext = string_format( pgettext( "talk option", "%1$c: %2$s" ), letter, text );
+    } else {
+         // dialogue w/ a % chance to work
+        //~ %1$c is an option letter and shouldn't be translated, %2$s is translated trial type, %3$d is a number, and %4$s is the translated response text
+        ftext = string_format( pgettext( "talk option", "%1$c: [%2$s %3$d%%] %4$s" ), letter,
+                               trial.name(), trial.calc_chance( d ), text );
     }
     parse_tags( ftext, *d.alpha, *d.beta );
 
@@ -1841,7 +1844,8 @@ talk_trial::talk_trial( JsonObject jo )
             WRAP( NONE ),
             WRAP( LIE ),
             WRAP( PERSUADE ),
-            WRAP( INTIMIDATE )
+            WRAP( INTIMIDATE ),
+            WRAP( CONDITION )
 #undef WRAP
         }
     };
@@ -1850,9 +1854,12 @@ talk_trial::talk_trial( JsonObject jo )
         jo.throw_error( "invalid talk trial type", "type" );
     }
     type = iter->second;
-    if( type != TALK_TRIAL_NONE ) {
+    if( !( type == TALK_TRIAL_NONE || type == TALK_TRIAL_CONDITION )  ) {
         difficulty = jo.get_int( "difficulty" );
     }
+
+    read_dialogue_condition( jo, condition, false );
+
     if( jo.has_array( "mod" ) ) {
         JsonArray ja = jo.get_array( "mod" );
         while( ja.has_more() ) {
@@ -2112,7 +2119,7 @@ void talk_effect_t::parse_sub_effect( JsonObject jo )
             const std::string dur_string = jo.get_string( "duration" );
             if( dur_string == "PERMANENT" ) {
                 subeffect_fun.set_u_add_permanent_effect( new_effect );
-            } else {
+            } else if( !dur_string.empty() && std::stoi( dur_string ) > 0 ) {
                 int duration = std::stoi( dur_string );
                 subeffect_fun.set_u_add_effect( new_effect, time_duration::from_turns( duration ) );
             }
@@ -2126,7 +2133,7 @@ void talk_effect_t::parse_sub_effect( JsonObject jo )
             const std::string dur_string = jo.get_string( "duration" );
             if( dur_string == "PERMANENT" ) {
                 subeffect_fun.set_npc_add_permanent_effect( new_effect );
-            } else {
+            } else if( !dur_string.empty() && std::stoi( dur_string ) > 0 ) {
                 int duration = std::stoi( dur_string );
                 subeffect_fun.set_npc_add_effect( new_effect,
                                                   time_duration::from_turns( duration ) );