import os
import tempfile
import hashlib
import gradio as gr

from embedding_manager import EmbeddingManager
from summarizer import PatientChartSummarizer
from hedis_engine import HedisComplianceEngine

APP_TITLE = "ChartWise AI"
DEFAULT_MEASURE_YEAR = 2024

# --- Simple in-process cache (per Space runtime) ---
# Maps content_hash -> vectordb
_VDB_CACHE = {}
_LAST_HASH = None  # optional: for quick reuse/debug

def _pdf_hash(pdf_bytes: bytes) -> str:
    return hashlib.sha256(pdf_bytes).hexdigest()

def _get_vectordb_from_bytes(pdf_bytes: bytes):
    """
    Return a cached vectordb for this PDF content if available,
    otherwise build it once and cache it for subsequent calls.
    """
    global _VDB_CACHE, _LAST_HASH

    content_hash = _pdf_hash(pdf_bytes)
    _LAST_HASH = content_hash

    if content_hash in _VDB_CACHE:
        print(f"[CACHE] Using cached vectordb for hash {content_hash[:12]}...")
        return _VDB_CACHE[content_hash]

    # Not cached yet: create temp file, build embeddings once, then cache
    with tempfile.NamedTemporaryFile(delete=False, suffix=".pdf") as tmp:
        tmp.write(pdf_bytes)
        pdf_path = tmp.name

    try:
        manager = EmbeddingManager(pdf_path)  # persists under ./embeddings/<temp_stem>
        vectordb = manager.get_or_create_embeddings()
        _VDB_CACHE[content_hash] = vectordb
        print(f"[CACHE] Cached vectordb for hash {content_hash[:12]}.")
        return vectordb
    finally:
        # Remove only the temp PDF; embeddings are persisted separately by EmbeddingManager
        try:
            os.unlink(pdf_path)
        except Exception:
            pass

# --- Handlers ---
def generate_patient_summary(pdf_file):
    try:
        if pdf_file is None:
            return "⚠️ Please upload a PDF file first."

        # Reuse embeddings if already built for this file
        vectordb = _get_vectordb_from_bytes(pdf_file)

        summarizer = PatientChartSummarizer(vectordb)
        result = summarizer.summarize_chart()
        return result
    except Exception as e:
        return f"❌ Error processing chart: {e}"

def generate_hedis_analysis(pdf_file, measure_name, measurement_year):
    try:
        if pdf_file is None:
            return "⚠️ Please upload a PDF file first."
        if not measure_name:
            return "⚠️ Please enter a HEDIS measure code (e.g., COL, BCS, CCS)."
        if not measurement_year:
            return "⚠️ Please enter a measurement year."

        # Reuse embeddings if already built for this file
        vectordb = _get_vectordb_from_bytes(pdf_file)

        hedis = HedisComplianceEngine(vectordb, measure_name, int(measurement_year))
        result = hedis.run()
        return result
    except Exception as e:
        return f"❌ Error processing HEDIS analysis: {e}"

# --- Gradio Theme ---
simple_theme = gr.themes.Soft(
    primary_hue=gr.themes.colors.blue,
    secondary_hue=gr.themes.colors.slate,
    neutral_hue=gr.themes.colors.slate,
).set(
    button_primary_background_fill="#1e40af",
    button_primary_background_fill_hover="#1d4ed8",
    button_primary_text_color="white",
    background_fill_primary="white",
    background_fill_secondary="#f8fafc",
)

# --- Interface ---
with gr.Blocks(theme=simple_theme, title="ChartWise AI") as interface:
    gr.HTML("<h1 style='text-align:center;color:#1e40af;'>🏥 ChartWise AI</h1>")
    gr.HTML("<p style='text-align:center;color:#64748b;'>Patient Chart Analysis &amp; HEDIS Compliance</p>")

    with gr.Row(equal_height=True):
        # Left: Patient Summary
        with gr.Column():
            gr.HTML("<h3 style='color:#1e40af;'>📋 Patient Chart Analysis</h3>")
            pdf_upload = gr.File(label="Upload Patient Chart (PDF)", file_types=[".pdf"], type="binary")
            summary_btn = gr.Button("📊 Generate Patient Summary", variant="primary")
            summary_output = gr.Markdown(
                label="Patient Summary Results",
                value="Upload a patient chart and click 'Generate Patient Summary' to see results here.",
                height=400
            )

        # Right: HEDIS
        with gr.Column():
            gr.HTML("<h3 style='color:#1e40af;'>🎯 HEDIS Measure Analysis</h3>")
            hedis_measure = gr.Textbox(
                label="HEDIS Measure Code",
                placeholder="e.g., COL, BCS, CCS, AAB",
                info="Measure code per NCQA HEDIS"
            )
            measurement_year = gr.Number(
                label="Measurement Year",
                value=DEFAULT_MEASURE_YEAR,
                precision=0,
                info="e.g., 2024"
            )
            hedis_btn = gr.Button("🎯 Run HEDIS Analysis", variant="secondary")
            hedis_output = gr.Markdown(
                label="HEDIS Analysis Results",
                value="Enter measure and year, then click 'Run HEDIS Analysis'.",
                height=400
            )

    # Wire events
    summary_btn.click(fn=generate_patient_summary, inputs=[pdf_upload], outputs=[summary_output])
    hedis_btn.click(fn=generate_hedis_analysis, inputs=[pdf_upload, hedis_measure, measurement_year], outputs=[hedis_output])

# Spaces auto-runs the script; these hints are fine, too:
if __name__ == "__main__":
    interface.queue().launch(server_name="0.0.0.0", server_port=int(os.environ.get("GRADIO_SERVER_PORT", "7860")))