#!/usr/bin/env python3
"""
QuestFlow: Visual quest logic.
Player has X, needs Y, give Z. O(1) evaluation. No conversation tree.

No dependencies. Pure Python.
"""
import time

# === THE LATTICE: quest state evaluation ===
QUESTS = {
    "the_lost_sword": {
        "title": "The Lost Sword",
        "start": {"npc": "old_hermit", "level": 3},
        "requires": {
            "lost_sword_piece_1": "explore_forest",
            "lost_sword_piece_2": "defeat_goblin_king",
            "lost_sword_piece_3": "dungeon_ruins"
        },
        "rewards": {
            "gold": 500,
            "xp": 1000,
            "item": "legendary_blade"
        },
        "status_atoms": {
            "not_started": "Ask the old hermit about the lost sword.",
            "in_progress": "Find the three pieces of the lost sword.",
            "ready_to_complete": "Bring the pieces to the hermit.",
            "completed": "You wield the Legendary Blade!"
        }
    },
    "rescue_the_princess": {
        "title": "Rescue the Princess",
        "start": {"npc": "king", "level": 5},
        "requires": {
            "rescue_key": "defeat_dragon",
            "rescue_map": "buy_from_merchant",
            "rescue_potion": "brew_alchemist"
        },
        "rewards": {
            "gold": 2000,
            "xp": 5000,
            "item": "royal_favor"
        },
        "status_atoms": {
            "not_started": "The king begs for your help.",
            "in_progress": "Gather what you need to storm the tower.",
            "ready_to_complete": "Storm the dragon's tower!",
            "completed": "The princess is safe. You are a hero."
        }
    },
    "find_the_artifact": {
        "title": "Find the Ancient Artifact",
        "start": {"npc": "scholar", "level": 8},
        "requires": {
            "artifact_clue_1": "read_ancient_book",
            "artifact_clue_2": "interview_ghost",
            "artifact_clue_3": "solve_riddle"
        },
        "rewards": {
            "gold": 5000,
            "xp": 10000,
            "item": "ancient_artifact"
        },
        "status_atoms": {
            "not_started": "The scholar seeks the ancient artifact.",
            "in_progress": "Follow the three clues.",
            "ready_to_complete": "Claim the artifact!",
            "completed": "The artifact is yours. Power flows."
        }
    },
    "clear_the_dungeon": {
        "title": "Clear the Haunted Dungeon",
        "start": {"npc": "guard_captain", "level": 4},
        "requires": {
            "dungeon_boss_defeated": "explore_dungeon"
        },
        "rewards": {
            "gold": 300,
            "xp": 800,
            "item": "dungeon_key"
        },
        "status_atoms": {
            "not_started": "The dungeon is overrun.",
            "in_progress": "Descend and clear all monsters.",
            "ready_to_complete": "The boss awaits!",
            "completed": "The dungeon is safe."
        }
    },
    "master_the_forge": {
        "title": "Master the Forge",
        "start": {"npc": "blacksmith", "level": 2},
        "requires": {
            "forge_hammer": "buy_supplies",
            "forge_anvil": "complete_tutorial",
            "forge_bellows": "gather_coal"
        },
        "rewards": {
            "gold": 200,
            "xp": 500,
            "item": "master_smith_title"
        },
        "status_atoms": {
            "not_started": "Learn smithing from the master.",
            "in_progress": "Gather forge components.",
            "ready_to_complete": "Build the forge!",
            "completed": "You are a Master Smith."
        }
    }
}

def evaluate_quest(quest_id: str, player_items: set) -> dict:
    """O(1) quest evaluation. Returns status, missing items, and rewards."""
    quest = QUESTS.get(quest_id)
    if not quest:
        return {"status": "unknown_quest", "quest_id": quest_id}

    required = set(quest["requires"].keys())
    has = player_items & required
    missing = required - player_items

    if len(missing) == 0:
        status = "ready_to_complete"
        progress = "100%"
    elif len(has) == 0:
        status = "not_started"
        progress = "0%"
    else:
        status = "in_progress"
        progress = f"{len(has)}/{len(required)}"

    return {
        "quest_id": quest_id,
        "title": quest["title"],
        "status": status,
        "progress": progress,
        "missing": list(missing),
        "hint": quest["status_atoms"].get(status, ""),
        "rewards": quest["rewards"] if status == "ready_to_complete" else None
    }

def get_quest_atom(quest_id: str, status: str) -> str:
    """O(1) quest status -> flavor text."""
    quest = QUESTS.get(quest_id)
    if not quest:
        return "Quest not found."
    return quest["status_atoms"].get(status, "Status unknown.")

# === DEMO ===
def demo():
    print("=" * 50)
    print("  QuestFlow: Visual quest logic, O(1) eval")
    print("=" * 50)
    print()

    # Scenario: player has some quest items
    player_inventory = {
        "lost_sword_piece_1",
        "lost_sword_piece_2",
        "dungeon_boss_defeated",
        "forge_hammer"
    }

    print(f"  Player inventory: {sorted(player_inventory)}")
    print()

    for quest_id in QUESTS.keys():
        start = time.perf_counter_ns()
        result = evaluate_quest(quest_id, player_inventory)
        elapsed = time.perf_counter_ns() - start

        status_icon = {
            "not_started": "[ ]",
            "in_progress": "[~]",
            "ready_to_complete": "[!]",
            "completed": "[X]"
        }.get(result["status"], "[?]")

        print(f"  {status_icon} {result['title']:30s} [{result['progress']}]  [{elapsed}ns]")
        print(f"     Status: {result['status']}")
        print(f"     Hint:   {result['hint']}")
        if result['missing']:
            print(f"     Missing: {', '.join(result['missing'])}")
        if result['rewards']:
            print(f"     REWARD: {result['rewards']}")
        print()

    print("=" * 50)
    print("  5 quests. 1 file. O(1) evaluation.")
    print("=" * 50)

if __name__ == "__main__":
    demo()