aether-shards/src/systems/MissionGenerator.js

/**
 * MissionGenerator.js
 * Factory that produces temporary Mission objects for Side Ops (procedural missions).
 *
 * @typedef {import("../managers/types.js").MissionDefinition} MissionDefinition
 */

/**
 * MissionGenerator
 * Generates procedural side missions based on campaign tier and unlocked regions.
 */
export class MissionGenerator {
  /**
   * Adjectives for mission naming (general flavor)
   */
  static ADJECTIVES = [
    "Silent",
    "Broken",
    "Red",
    "Crimson",
    "Shattered",
    "Frozen",
    "Burning",
    "Dark",
    "Blind",
    "Hidden",
    "Lost",
    "Ancient",
    "Hollow",
    "Swift",
  ];

  /**
   * Nouns for Skirmish (Combat) missions
   */
  static NOUNS_SKIRMISH = [
    "Thunder",
    "Storm",
    "Iron",
    "Fury",
    "Shield",
    "Hammer",
    "Wrath",
    "Wall",
    "Strike",
    "Anvil",
  ];

  /**
   * Nouns for Salvage (Loot) missions
   */
  static NOUNS_SALVAGE = [
    "Cache",
    "Vault",
    "Echo",
    "Spark",
    "Core",
    "Grip",
    "Harvest",
    "Trove",
    "Fragment",
    "Salvage",
  ];

  /**
   * Nouns for Eliminate Unit missions
   */
  static NOUNS_ELIMINATE_UNIT = [
    "Viper",
    "Dagger",
    "Fang",
    "Night",
    "Shadow",
    "End",
    "Hunt",
    "Razor",
    "Ghost",
    "Sting",
  ];

  /**
   * Nouns for Recon (Explore) missions
   */
  static NOUNS_RECON = [
    "Eye",
    "Watch",
    "Path",
    "Horizon",
    "Whisper",
    "Dawn",
    "Light",
    "Step",
    "Vision",
    "Scope",
  ];

  /**
   * Tier configuration: [Name, Enemy Level Range, Reward Multiplier]
   */
  static TIER_CONFIG = {
    1: { name: "Recon", enemyLevel: [1, 2], multiplier: 1.0 },
    2: { name: "Patrol", enemyLevel: [3, 4], multiplier: 1.5 },
    3: { name: "Conflict", enemyLevel: [5, 6], multiplier: 2.5 },
    4: { name: "War", enemyLevel: [7, 8], multiplier: 4.0 },
    5: { name: "Suicide", enemyLevel: [9, 10], multiplier: 6.0 },
  };

  /**
   * Maps biome types to faction IDs for reputation rewards
   */
  static BIOME_TO_FACTION = {
    BIOME_FUNGAL_CAVES: "ARCANE_DOMINION",
    BIOME_RUSTING_WASTES: "COGWORK_CONCORD",
    BIOME_CRYSTAL_SPIRES: "ARCANE_DOMINION",
    BIOME_VOID_SEEP: "SHADOW_COVENANT",
    BIOME_CONTESTED_FRONTIER: "IRON_LEGION",
  };

  /**
   * Templates for dynamic narrative generation
   */
  static NARRATIVE_TEMPLATES = {
    INTRO: {
      IRON_LEGION: {
        speaker: "General Kael",
        portrait: "assets/images/portraits/vanguard.png",
        text: "Commander, Iron Legion scouts report {enemy} activity in {biome}. We need you to {verb} them immediately.",
      },
      ARCANE_DOMINION: {
        speaker: "Magister Varen",
        portrait: "assets/images/portraits/arcanist.png",
        text: "Readings indicate {enemy} disturbances in {biome}. Eliminate the threat before it destabilizes the region.",
      },
      COGWORK_CONCORD: {
        speaker: "Chief Engineer Rix",
        portrait: "assets/images/portraits/engineer.png",
        text: "We've got a situation in {biome}. {enemy} units are interfering with our operations. Shut them down.",
      },
      SHADOW_COVENANT: {
        speaker: "Whisper",
        portrait: "assets/images/portraits/rogue.png",
        text: "A target of interest has appeared in {biome}. {enemy} forces are guarding it. Remove them.",
      },
    },
    OUTRO: {
      IRON_LEGION: {
        speaker: "General Kael",
        portrait: "assets/images/portraits/vanguard.png",
        text: "Target neutralized. Funds transferred. Good hunting, Explorer.",
      },
      ARCANE_DOMINION: {
        speaker: "Magister Varen",
        portrait: "assets/images/portraits/arcanist.png",
        text: "The anomaly has been corrected. Payment has been sent.",
      },
      COGWORK_CONCORD: {
        speaker: "Chief Engineer Rix",
        portrait: "assets/images/portraits/engineer.png",
        text: "Efficiency restored. Your compensation is in the account.",
      },
      SHADOW_COVENANT: {
        speaker: "Whisper",
        portrait: "assets/images/portraits/rogue.png",
        text: "Done and dusted. The Covenant remembers your service.",
      },
    },
  };

  /**
   * Map of biomes to potential hazards
   */
  static BIOME_HAZARDS = {
    BIOME_FUNGAL_CAVES: ["HAZARD_POISON_SPORES", "HAZARD_ACID_POOLS"],
    BIOME_RUSTING_WASTES: ["HAZARD_RADIATION_ZONES", "HAZARD_MAGNETIC_STORM"],
    BIOME_CRYSTAL_SPIRES: ["HAZARD_MANA_STORM", "HAZARD_CRYSTAL_RESONANCE"],
    BIOME_VOID_SEEP: ["HAZARD_VOID_POCKETS", "HAZARD_GRAVITY_FLUX"],
    BIOME_CONTESTED_FRONTIER: ["HAZARD_ARTILLERY_STRIKE", "HAZARD_MINEFIELD"],
  };

  /**
   * Converts a number to Roman numeral
   * @param {number} num - Number to convert (2-4)
   * @returns {string} Roman numeral
   */
  static toRomanNumeral(num) {
    const roman = ["", "I", "II", "III", "IV", "V"];
    return roman[num] || "";
  }

  /**
   * Extracts the base name (adjective + noun) from a mission title
   * @param {string} title - Mission title (e.g., "Operation: Silent Viper II")
   * @returns {string} Base name (e.g., "Silent Viper")
   */
  static extractBaseName(title) {
    // Remove "Operation: " prefix and any Roman numeral suffix
    const match = title.match(/Operation:\s*(.+?)(?:\s+[IVX]+)?$/);
    if (match) {
      return match[1].trim();
    }
    return title
      .replace(/Operation:\s*/, "")
      .replace(/\s+[IVX]+$/, "")
      .trim();
  }

  /**
   * Finds the highest Roman numeral in history for a given base name
   * @param {string} baseName - Base name (e.g., "Silent Viper")
   * @param {Array<string>} history - Array of completed mission titles or IDs
   * @returns {number} Highest numeral found (0 if none)
   */
  static findHighestNumeral(baseName, history) {
    let highest = 0;
    const pattern = new RegExp(
      `Operation:\\s*${baseName.replace(
        /[.*+?^${}()|[\]\\]/g,
        "\\$&"
      )}\\s+([IVX]+)`,
      "i"
    );

    for (const entry of history) {
      const match = entry.match(pattern);
      if (match) {
        const roman = match[1];
        const num = this.romanToNumber(roman);
        if (num > highest) {
          highest = num;
        }
      }
    }

    return highest;
  }

  /**
   * Converts Roman numeral to number
   * @param {string} roman - Roman numeral string
   * @returns {number} Number value
   */
  static romanToNumber(roman) {
    const map = { I: 1, II: 2, III: 3, IV: 4, V: 5 };
    return map[roman] || 0;
  }

  /**
   * Selects a random element from an array
   * @param {Array<T>} array - Array to select from
   * @returns {T} Random element
   * @template T
   */
  static randomChoice(array) {
    return array[Math.floor(Math.random() * array.length)];
  }

  /**
   * Generates a random number between min and max (inclusive)
   * @param {number} min - Minimum value
   * @param {number} max - Maximum value
   * @returns {number} Random number
   */
  static randomRange(min, max) {
    return Math.floor(Math.random() * (max - min + 1)) + min;
  }

  /**
   * Generates a random float between min and max
   * @param {number} min - Minimum value
   * @param {number} max - Maximum value
   * @returns {number} Random float
   */
  static randomFloat(min, max) {
    return Math.random() * (max - min) + min;
  }

  /**
   * Selects a biome from unlocked regions with weighting
   * @param {Array<string>} unlockedRegions - Array of biome type IDs
   * @returns {string} Selected biome type
   */
  static selectBiome(unlockedRegions) {
    if (unlockedRegions.length === 0) {
      // Default fallback
      return "BIOME_RUSTING_WASTES";
    }

    // 40% chance for the most recently unlocked region (last in array)
    if (Math.random() < 0.4 && unlockedRegions.length > 0) {
      return unlockedRegions[unlockedRegions.length - 1];
    }

    // Otherwise random selection
    return this.randomChoice(unlockedRegions);
  }

  /**
   * Generates a Side Op mission
   * @param {number} tier - Campaign tier (1-5)
   * @param {Array<string>} unlockedRegions - Array of biome type IDs
   * @param {Array<string>} history - Array of completed mission titles or IDs
   * @returns {MissionDefinition} Generated mission object
   */
  static generateSideOp(tier, unlockedRegions, history = []) {
    // Validate tier
    const validTier = Math.max(1, Math.min(5, tier));
    const tierConfig = this.TIER_CONFIG[validTier];

    // Select archetype
    const archetypes = ["SKIRMISH", "SALVAGE", "ELIMINATE_UNIT", "RECON"];
    const archetype = this.randomChoice(archetypes);

    // Select noun based on archetype
    let noun;
    switch (archetype) {
      case "SKIRMISH":
        noun = this.randomChoice(this.NOUNS_SKIRMISH);
        break;
      case "SALVAGE":
        noun = this.randomChoice(this.NOUNS_SALVAGE);
        break;
      case "ELIMINATE_UNIT":
        noun = this.randomChoice(this.NOUNS_ELIMINATE_UNIT);
        break;
      case "RECON":
        noun = this.randomChoice(this.NOUNS_RECON);
        break;
      default:
        noun = this.randomChoice(this.NOUNS_SKIRMISH);
    }

    // Select adjective
    const adjective = this.randomChoice(this.ADJECTIVES);

    // Check history for series
    const baseName = `${adjective} ${noun}`;
    const highestNumeral = this.findHighestNumeral(baseName, history);
    const nextNumeral = highestNumeral + 1;
    const romanSuffix =
      nextNumeral > 1 ? ` ${this.toRomanNumeral(nextNumeral)}` : "";

    // Build title
    const title = `Operation: ${baseName}${romanSuffix}`;

    // Select biome
    const biomeType = this.selectBiome(unlockedRegions);

    // Generate objectives based on archetype
    const objectives = this.generateObjectives(archetype, validTier);

    // Generate biome config based on archetype
    const biomeConfig = this.generateBiomeConfig(archetype, biomeType);

    // Generate enemy spawns based on archetype (especially for ASSASSINATION)
    const enemySpawns = this.generateEnemySpawns(
      archetype,
      objectives,
      validTier
    );

    // Calculate rewards
    const rewards = this.calculateRewards(validTier, archetype, biomeType);

    // Determine Faction ID for narrative
    const factionId = this.BIOME_TO_FACTION[biomeType] || "IRON_LEGION";

    // Generate unique ID (timestamp + random to ensure uniqueness)
    const missionId = `SIDE_OP_${Date.now()}_${Math.random()
      .toString(36)
      .substring(2, 9)}`;

    // Generate Narrative
    const narrative = this.generateNarrative(
      missionId,
      archetype,
      biomeType,
      factionId
    );

    // Build mission object
    const mission = {
      id: missionId,
      type: "SIDE_QUEST",
      config: {
        title: title,
        description: this.generateDescription(archetype, biomeType),
        difficulty_tier: validTier,
        recommended_level: tierConfig.enemyLevel[1], // Use max enemy level as recommended
      },
      biome: biomeConfig,
      deployment: {
        squad_size_limit: 4,
      },
      narrative: narrative,
      objectives: objectives,
      enemy_spawns: enemySpawns,
      rewards: rewards,
      expiresIn: 3, // Expires in 3 campaign days
    };

    // Add boss config for Eliminate Unit missions
    if (archetype === "ELIMINATE_UNIT") {
      // Find target ID from objectives
      const targetObj = objectives.primary.find(
        (o) => o.type === "ELIMINATE_UNIT"
      );
      if (targetObj?.target_def_id) {
        mission.config.boss_config = {
          target_def_id: targetObj.target_def_id,
          name: `${this.randomChoice([
            "Krag",
            "Vorak",
            "Xol",
            "Zea",
          ])} the ${this.randomChoice(["Breaker", "Rot", "Vile", "Ender"])}`,
          stats: {
            hp_multiplier: 2.0,
            attack_multiplier: 1.5,
          },
        };
      }
    }

    return mission;
  }

  /**
   * Generates dynamic narrative for the mission
   * @param {string} missionId - The unique ID of the mission
   * @param {string} archetype - Mission archetype
   * @param {string} biomeType - Biome type
   * @param {string} factionId - Faction ID requesting the mission
   * @returns {Object} Narrative object with intro/outro and dynamic data
   */
  static generateNarrative(missionId, archetype, biomeType, factionId) {
    const introId = `NARRATIVE_${missionId}_INTRO`;
    const outroId = `NARRATIVE_${missionId}_OUTRO`;

    // Get templates (fallback to Iron Legion if missing)
    const introTemplate =
      this.NARRATIVE_TEMPLATES.INTRO[factionId] ||
      this.NARRATIVE_TEMPLATES.INTRO["IRON_LEGION"];
    const outroTemplate =
      this.NARRATIVE_TEMPLATES.OUTRO[factionId] ||
      this.NARRATIVE_TEMPLATES.OUTRO["IRON_LEGION"];

    // Format Strings
    const biomeName = biomeType.replace("BIOME_", "").replace("_", " ");
    let verb = "eliminate";
    switch (archetype) {
      case "SALVAGE":
        verb = "recover";
        break;
      case "RECON":
        verb = "scout";
        break;
      case "ELIMINATE_UNIT":
        verb = "assassinate";
        break;
    }

    const introText = introTemplate.text
      .replace("{enemy}", "hostile")
      .replace("{biome}", biomeName.toLowerCase())
      .replace("{verb}", verb);

    return {
      intro_sequence: introId,
      outro_success: outroId,
      _dynamic_data: {
        [introId]: {
          id: introId,
          nodes: [
            {
              id: "1",
              type: "DIALOGUE",
              speaker: introTemplate.speaker,
              portrait: introTemplate.portrait,
              text: introText,
              next: "END",
            },
          ],
        },
        [outroId]: {
          id: outroId,
          nodes: [
            {
              id: "1",
              type: "DIALOGUE",
              speaker: outroTemplate.speaker,
              portrait: outroTemplate.portrait,
              text: outroTemplate.text,
              next: "END",
            },
          ],
        },
      },
    };
  }

  /**
   * Generates objectives based on archetype
   * @param {string} archetype - Mission archetype
   * @param {number} tier - Difficulty tier
   * @returns {Object} Objectives object
   */
  static generateObjectives(archetype, tier) {
    switch (archetype) {
      case "SKIRMISH":
        return {
          primary: [
            {
              id: "OBJ_ELIMINATE_ALL",
              type: "ELIMINATE_ALL",
              description: "Clear the sector of hostile forces.",
            },
          ],
          failure_conditions: [{ type: "SQUAD_WIPE" }],
        };

      case "SALVAGE":
        const crateCount = this.randomRange(3, 5);
        return {
          primary: [
            {
              id: "OBJ_SALVAGE",
              type: "INTERACT",
              target_object_id: "OBJ_SUPPLY_CRATE",
              target_count: crateCount,
              description: `Recover ${crateCount} supply crates before the enemy secures them.`,
            },
          ],
          failure_conditions: [{ type: "SQUAD_WIPE" }],
        };

      case "ELIMINATE_UNIT":
        // Generate a random elite enemy ID
        const eliteEnemies = [
          "ENEMY_ELITE_ECHO",
          "ENEMY_ELITE_BREAKER",
          "ENEMY_ELITE_STALKER",
          "ENEMY_ELITE_WARDEN",
        ];
        const targetId = this.randomChoice(eliteEnemies);
        return {
          primary: [
            {
              id: "OBJ_HUNT",
              type: "ELIMINATE_UNIT",
              target_def_id: targetId,
              target_count: 1, // Explicitly set to 1 for single target elimination
              description:
                "A High-Value Target has been spotted. Eliminate them.",
            },
          ],
          failure_conditions: [{ type: "SQUAD_WIPE" }],
        };

      case "RECON":
        // Generate 3 zone coordinates (simplified - actual zones would be set during mission generation)
        // Turn limit: 15 + (tier * 5) turns for RECON missions
        const turnLimit = 15 + tier * 5;
        return {
          primary: [
            {
              id: "OBJ_RECON",
              type: "REACH_ZONE",
              target_count: 3,
              description: "Survey the designated coordinates.",
            },
          ],
          failure_conditions: [
            { type: "SQUAD_WIPE" },
            { type: "TURN_LIMIT_EXCEEDED", turn_limit: turnLimit },
          ],
        };

      default:
        return {
          primary: [
            {
              id: "OBJ_DEFAULT",
              type: "ELIMINATE_ALL",
              description: "Complete the mission objectives.",
            },
          ],
          failure_conditions: [{ type: "SQUAD_WIPE" }],
        };
    }
  }

  /**
   * Generates enemy spawns based on archetype and objectives
   * @param {string} archetype - Mission archetype
   * @param {Object} objectives - Generated objectives
   * @param {number} tier - Difficulty tier
   * @returns {Array<EnemySpawn>} Array of enemy spawn definitions
   */
  static generateEnemySpawns(archetype, objectives, tier) {
    const spawns = [];

    switch (archetype) {
      case "ELIMINATE_UNIT":
        // For ELIMINATE_UNIT, spawn the target enemy from the ELIMINATE_UNIT objective
        const eliminateUnitObj = objectives.primary?.find(
          (obj) => obj.type === "ELIMINATE_UNIT"
        );
        if (eliminateUnitObj?.target_def_id) {
          spawns.push({
            enemy_def_id: eliminateUnitObj.target_def_id,
            count: 1,
          });
        }
        // Also spawn some regular enemies for support
        const regularEnemies = [
          "ENEMY_SHARDBORN_SENTINEL",
          "ENEMY_GOBLIN_RAIDER",
          "ENEMY_CRYSTAL_SHARD",
        ];
        const supportEnemy = this.randomChoice(regularEnemies);
        spawns.push({
          enemy_def_id: supportEnemy,
          count: Math.max(1, Math.floor(tier / 2)), // 1-2 support enemies based on tier
        });
        break;

      case "SKIRMISH":
        // Skirmish missions spawn a mix of enemies
        const skirmishEnemies = [
          "ENEMY_SHARDBORN_SENTINEL",
          "ENEMY_GOBLIN_RAIDER",
          "ENEMY_CRYSTAL_SHARD",
        ];
        const totalSkirmish = 3 + tier; // 4-8 enemies based on tier
        for (let i = 0; i < totalSkirmish; i++) {
          const enemyType = this.randomChoice(skirmishEnemies);
          const existingSpawn = spawns.find(
            (s) => s.enemy_def_id === enemyType
          );
          if (existingSpawn) {
            existingSpawn.count++;
          } else {
            spawns.push({ enemy_def_id: enemyType, count: 1 });
          }
        }
        break;

      case "SALVAGE":
      case "RECON":
        // These missions have fewer enemies (lower density)
        const lightEnemies = [
          "ENEMY_SHARDBORN_SENTINEL",
          "ENEMY_GOBLIN_RAIDER",
        ];
        const totalLight = Math.max(1, tier); // 1-5 enemies based on tier
        for (let i = 0; i < totalLight; i++) {
          const enemyType = this.randomChoice(lightEnemies);
          const existingSpawn = spawns.find(
            (s) => s.enemy_def_id === enemyType
          );
          if (existingSpawn) {
            existingSpawn.count++;
          } else {
            spawns.push({ enemy_def_id: enemyType, count: 1 });
          }
        }
        break;

      default:
        // Default: spawn a few basic enemies
        spawns.push({
          enemy_def_id: "ENEMY_SHARDBORN_SENTINEL",
          count: Math.max(1, tier),
        });
    }

    return spawns;
  }

  /**
   * Generates biome configuration based on archetype
   * @param {string} archetype - Mission archetype
   * @param {string} biomeType - Biome type ID
   * @returns {Object} Biome configuration
   */
  static generateBiomeConfig(archetype, biomeType) {
    let size, roomCount, density;

    switch (archetype) {
      case "SKIRMISH":
        size = { x: 20, y: 12, z: 20 };
        roomCount = 6;
        density = "MEDIUM";
        break;

      case "SALVAGE":
        size = { x: 18, y: 12, z: 18 };
        roomCount = 5;
        density = "HIGH"; // High density for obstacles/cover
        break;

      case "ELIMINATE_UNIT":
        size = { x: 22, y: 12, z: 22 };
        roomCount = 7;
        density = "MEDIUM";
        break;

      case "RECON":
        size = { x: 24, y: 12, z: 24 }; // Large map
        roomCount = 8;
        density = "LOW"; // Low enemy density
        break;

      default:
        size = { x: 20, y: 12, z: 20 };
        roomCount = 6;
        density = "MEDIUM";
    }

    // Roll for Hazards (30% chance)
    const hazards = [];
    const allowedHazards = this.BIOME_HAZARDS[biomeType];
    if (allowedHazards && Math.random() < 0.3) {
      hazards.push(this.randomChoice(allowedHazards));
    }

    return {
      type: biomeType,
      hazards: hazards,
      generator_config: {
        seed_type: "RANDOM",
        size: size,
        room_count: roomCount,
        density: density,
      },
    };
  }

  /**
   * Generates mission description based on archetype and biome
   * @param {string} archetype - Mission archetype
   * @param {string} biomeType - Biome type ID
   * @returns {string} Description text
   */
  static generateDescription(archetype, biomeType) {
    const biomeNames = {
      BIOME_FUNGAL_CAVES: "Fungal Caves",
      BIOME_RUSTING_WASTES: "Rusting Wastes",
      BIOME_CRYSTAL_SPIRES: "Crystal Spires",
      BIOME_VOID_SEEP: "Void Seep",
      BIOME_CONTESTED_FRONTIER: "Contested Frontier",
    };
    const biomeName = biomeNames[biomeType] || "the region";

    switch (archetype) {
      case "SKIRMISH":
        return `Clear the sector of hostile forces in ${biomeName}.`;
      case "SALVAGE":
        return `Recover lost supplies before the enemy secures them in ${biomeName}.`;
      case "ELIMINATE_UNIT":
        return `A High-Value Target has been spotted in ${biomeName}. Eliminate them.`;
      case "RECON":
        return `Survey the designated coordinates in ${biomeName}.`;
      default:
        return `Complete the mission objectives in ${biomeName}.`;
    }
  }

  /**
   * Calculates rewards based on tier and archetype
   * @param {number} tier - Difficulty tier
   * @param {string} archetype - Mission archetype
   * @param {string} biomeType - Biome type ID
   * @returns {Object} Rewards object
   */
  static calculateRewards(tier, archetype, biomeType) {
    const tierConfig = this.TIER_CONFIG[tier];
    const multiplier = tierConfig.multiplier;

    // Base currency calculation: Base (50) * TierMultiplier * Random(0.8, 1.2)
    const baseCurrency = 50;
    const randomFactor = this.randomFloat(0.8, 1.2);
    const currencyAmount = Math.round(baseCurrency * multiplier * randomFactor);

    // XP calculation (base 100 * multiplier)
    const baseXP = 100;
    const xpAmount = Math.round(
      baseXP * multiplier * this.randomFloat(0.9, 1.1)
    );

    // Eliminate Unit missions get bonus currency
    let finalCurrency = currencyAmount;
    if (archetype === "ELIMINATE_UNIT") {
      finalCurrency = Math.round(finalCurrency * 1.5);
    }

    // Items: 20% chance per Tier to drop a Chest Key or Item
    const items = [];
    const itemChance = tier * 0.2;
    if (Math.random() < itemChance) {
      // Randomly choose between chest key or item
      if (Math.random() < 0.5) {
        items.push("ITEM_CHEST_KEY");
      } else {
        // Generic item - would need item registry in real implementation
        items.push("ITEM_MATERIAL_SCRAP");
      }
    }

    // Reputation: +10 with the Region's owner
    const factionId = this.BIOME_TO_FACTION[biomeType] || "IRON_LEGION";
    const reputation = 10;

    const rewards = {
      guaranteed: {
        xp: xpAmount,
        currency: {
          aether_shards: finalCurrency,
        },
      },
      faction_reputation: {
        [factionId]: reputation,
      },
    };

    // Add items if any
    if (items.length > 0) {
      rewards.guaranteed.items = items;
    }

    return rewards;
  }

  /**
   * Refreshes the mission board, filling it up to 5 entries and removing expired missions
   * @param {Array<MissionDefinition>} currentMissions - Current list of available missions
   * @param {number} tier - Current campaign tier
   * @param {Array<string>} unlockedRegions - Array of unlocked biome type IDs
   * @param {Array<string>} history - Array of completed mission titles or IDs
   * @param {boolean} isDailyReset - If true, decrements expiresIn for all missions
   * @returns {Array<MissionDefinition>} Updated mission list
   */
  static refreshBoard(
    currentMissions = [],
    tier,
    unlockedRegions,
    history = [],
    isDailyReset = false
  ) {
    // On daily reset, decrement expiresIn for all missions
    let validMissions = currentMissions;
    if (isDailyReset) {
      validMissions = currentMissions.map((mission) => {
        if (mission.expiresIn !== undefined) {
          const updated = { ...mission };
          updated.expiresIn = (mission.expiresIn || 3) - 1;
          return updated;
        }
        return mission;
      });
    }

    // Remove missions that have expired (expiresIn <= 0)
    validMissions = validMissions.filter((mission) => {
      if (mission.expiresIn !== undefined) {
        return mission.expiresIn > 0;
      }
      // Keep missions without expiration tracking
      return true;
    });

    // Fill up to 5 missions
    const targetCount = 5;
    const needed = Math.max(0, targetCount - validMissions.length);

    const newMissions = [];
    for (let i = 0; i < needed; i++) {
      const mission = this.generateSideOp(tier, unlockedRegions, history);
      newMissions.push(mission);
    }

    // Combine and return
    return [...validMissions, ...newMissions];
  }
}