import streamlit as st  # 🌐 Streamlit magic
import streamlit.components.v1 as components  # 🖼️ Embed custom HTML/JS
import os  # 📂 File operations
import json  # 🔄 JSON encoding/decoding
import pandas as pd  # 📊 DataFrame handling
import uuid  # 🆔 Unique IDs
import math  # ➗ Math utils
import time  # ⏳ Time utilities

from gamestate import GameState  # 💼 Shared game-state singleton

# 🚀 Page setup
st.set_page_config(page_title="Infinite World Builder", layout="wide")

# 📏 Constants for world dimensions & CSV schema
SAVE_DIR = "saved_worlds"
PLOT_WIDTH = 50.0  # ↔️ Plot width in world units
PLOT_DEPTH = 50.0  # ↕️ Plot depth in world units
CSV_COLUMNS = [
    'obj_id', 'type',
    'pos_x', 'pos_y', 'pos_z',
    'rot_x', 'rot_y', 'rot_z', 'rot_order'
]

# 🗂️ Ensure directory for plots exists
os.makedirs(SAVE_DIR, exist_ok=True)

@st.cache_data(ttl=3600)  # 🕒 Cache for 1h
def load_plot_metadata():
    # 🔍 Scan SAVE_DIR for plot CSVs
    try:
        plot_files = [f for f in os.listdir(SAVE_DIR)
                      if f.endswith(".csv") and f.startswith("plot_X")]
    except FileNotFoundError:
        st.error(f"Folder '{SAVE_DIR}' missing! 🚨")
        return []
    except Exception as e:
        st.error(f"Error reading '{SAVE_DIR}': {e}")
        return []

    parsed = []
    for fn in plot_files:
        try:
            parts = fn[:-4].split('_')  # strip .csv
            gx = int(parts[1][1:])  # X index
            gz = int(parts[2][1:])  # Z index
            name = " ".join(parts[3:]) if len(parts)>3 else f"Plot({gx},{gz})"
            parsed.append({
                'id': fn[:-4],
                'filename': fn,
                'grid_x': gx,
                'grid_z': gz,
                'name': name,
                'x_offset': gx * PLOT_WIDTH,
                'z_offset': gz * PLOT_DEPTH
            })
        except Exception:
            st.warning(f"Skip invalid file: {fn}")
    parsed.sort(key=lambda p: (p['grid_x'], p['grid_z']))
    return parsed


def load_plot_objects(filename, x_offset, z_offset):
    # 📥 Load objects from a plot CSV and shift by offsets
    path = os.path.join(SAVE_DIR, filename)
    try:
        df = pd.read_csv(path)
        # 🛡️ Ensure essentials exist
        if not all(c in df.columns for c in ['type','pos_x','pos_y','pos_z']):
            st.warning(f"Missing cols in {filename} 🧐")
            return []
        # 🆔 Guarantee obj_id
        df['obj_id'] = df.get('obj_id', pd.Series([str(uuid.uuid4()) for _ in df.index]))
        # 🔄 Fill missing rotation
        for col, default in [('rot_x',0.0),('rot_y',0.0),('rot_z',0.0),('rot_order','XYZ')]:
            if col not in df.columns:
                df[col] = default

        objs = []
        for _, row in df.iterrows():
            o = row.to_dict()
            o['pos_x'] += x_offset
            o['pos_z'] += z_offset
            objs.append(o)
        return objs
    except FileNotFoundError:
        st.error(f"CSV not found: {filename}")
        return []
    except pd.errors.EmptyDataError:
        return []
    except Exception as e:
        st.error(f"Load error {filename}: {e}")
        return []


def save_plot_data(filename, objects_list, px, pz):
    # 💾 Save list of new objects relative to plot origin
    path = os.path.join(SAVE_DIR, filename)
    if not isinstance(objects_list, list):
        st.error("👎 Invalid data format for save")
        return False

    rel = []
    for o in objects_list:
        pos = o.get('position', {})
        rot = o.get('rotation', {})
        typ = o.get('type','Unknown')
        oid = o.get('obj_id', str(uuid.uuid4()))
        # 🛑 Skip bad objects
        if not all(k in pos for k in ['x','y','z']) or typ=='Unknown':
            continue
        rel.append({
            'obj_id': oid, 'type': typ,
            'pos_x': pos['x']-px, 'pos_y': pos['y'], 'pos_z': pos['z']-pz,
            'rot_x': rot.get('_x',0.0), 'rot_y': rot.get('_y',0.0),
            'rot_z': rot.get('_z',0.0), 'rot_order': rot.get('_order','XYZ')
        })
    try:
        pd.DataFrame(rel, columns=CSV_COLUMNS).to_csv(path, index=False)
        st.success(f"🎉 Saved {len(rel)} to {filename}")
        return True
    except Exception as e:
        st.error(f"Save failed: {e}")
        return False

# 🔒 Singleton for global world state
@st.cache_resource
def get_game_state():
    return GameState(save_dir=SAVE_DIR, csv_filename="world_state.csv")

game_state = get_game_state()

# 🧠 Session state defaults
st.session_state.setdefault('selected_object','None')
st.session_state.setdefault('new_plot_name','')
st.session_state.setdefault('js_save_data_result',None)

# 🔄 Load everything
plots_metadata = load_plot_metadata()
all_initial_objects = []
for p in plots_metadata:
    all_initial_objects += load_plot_objects(p['filename'], p['x_offset'], p['z_offset'])

# 🖥️ Sidebar UI
with st.sidebar:
    st.title("🏗️ World Controls")
    st.header("📍 Navigate Plots")
    cols = st.columns(2)
    i = 0
    for p in sorted(plots_metadata, key=lambda x:(x['grid_x'],x['grid_z'])):
        label = f"➡️ {p['name']} ({p['grid_x']},{p['grid_z']})"
        if cols[i].button(label, key=f"nav_{p['id']}"):
            try:
                from streamlit_js_eval import streamlit_js_eval
                js = f"teleportPlayer({p['x_offset']+PLOT_WIDTH/2},{p['z_offset']+PLOT_DEPTH/2});"
                streamlit_js_eval(js_code=js, key=f"tp_{p['id']}")
            except Exception as e:
                st.error(f"TP fail: {e}")
        i = (i+1)%2

    st.markdown("---")
    st.header("🌲 Place Objects")
    opts = ["None","Simple House","Tree","Rock","Fence Post"]
    idx = opts.index(st.session_state.selected_object) if st.session_state.selected_object in opts else 0
    sel = st.selectbox("Select:", opts, index=idx, key="selected_object_widget")
    if sel != st.session_state.selected_object:
        st.session_state.selected_object = sel

    st.markdown("---")
    st.header("💾 Save Work")
    if st.button("💾 Save Current Work", key="save_button"):
        from streamlit_js_eval import streamlit_js_eval
        streamlit_js_eval(js_code="getSaveDataAndPosition();", key="js_save_processor")
        st.rerun()

# 📨 Handle incoming save data
raw = st.session_state.get("js_save_processor")
if raw:
    st.info("📬 Got save data!")
    ok=False
    try:
        pay = json.loads(raw) if isinstance(raw,str) else raw
        pos, objs = pay.get('playerPosition'), pay.get('objectsToSave')
        if isinstance(objs,list) and pos:
            gx, gz = math.floor(pos['x']/PLOT_WIDTH), math.floor(pos['z']/PLOT_DEPTH)
            fn = f"plot_X{gx}_Z{gz}.csv"
            if save_plot_data(fn, objs, gx*PLOT_WIDTH, gz*PLOT_DEPTH):
                load_plot_metadata.clear()
                try:
                    from streamlit_js_eval import streamlit_js_eval
                    streamlit_js_eval(js_code="resetNewlyPlacedObjects();", key="reset_js")
                except:
                    pass
                game_state.update_state(objs)
                ok=True
        if not ok:
            st.error("❌ Save error")
    except Exception as e:
        st.error(f"Err: {e}")
    st.session_state.js_save_processor=None
    if ok: st.rerun()

# 🏠 Main view
st.header("🌍 Infinite Shared 3D World")
st.caption("➡️ Explore, click to build, 💾 to save!")

# 🔌 Inject state into JS
state = {
    "ALL_INITIAL_OBJECTS": all_initial_objects,
    "PLOTS_METADATA": plots_metadata,
    "SELECTED_OBJECT_TYPE": st.session_state.selected_object,
    "PLOT_WIDTH": PLOT_WIDTH,
    "PLOT_DEPTH": PLOT_DEPTH,
    "GAME_STATE": game_state.get_state()
}

try:
    with open('index.html','r',encoding='utf-8') as f:
        html = f.read()
    script = f"""
<script>
    window.ALL_INITIAL_OBJECTS = {json.dumps(state['ALL_INITIAL_OBJECTS'])};
    window.PLOTS_METADATA   = {json.dumps(state['PLOTS_METADATA'])};
    window.SELECTED_OBJECT_TYPE = {json.dumps(state['SELECTED_OBJECT_TYPE'])};
    window.PLOT_WIDTH = {json.dumps(state['PLOT_WIDTH'])};
    window.PLOT_DEPTH = {json.dumps(state['PLOT_DEPTH'])};
    window.GAME_STATE = {json.dumps(state['GAME_STATE'])};
    console.log('👍 State injected!', {{
        objs: window.ALL_INITIAL_OBJECTS.length,
        plots: window.PLOTS_METADATA.length,
        gs: window.GAME_STATE.length
    }});
</script>
"""
    html = html.replace('</head>', script + '\n</head>', 1)
    components.html(html, height=750, scrolling=False)
except FileNotFoundError:
    st.error("❌ index.html missing!")
except Exception as e:
    st.error(f"😱 HTML inject failed: {e}")