import os

from fastapi import FastAPI, Query
from fastapi.middleware.cors import CORSMiddleware
from fastapi.responses import HTMLResponse
from fastapi.staticfiles import StaticFiles

from app.services.data_service import data_service
from app.services.count_converter import (
    convert_count,
    get_available_standard_counts,
    get_available_ply_counts,
    nearest_standard_counts,
    parse_count_string,
)
from app.services.reed_calculator import get_reed_range

app = FastAPI(title="PDC Intelligence API", version="2.0.0")

app.add_middleware(
    CORSMiddleware,
    allow_origins=["*"],
    allow_credentials=True,
    allow_methods=["*"],
    allow_headers=["*"],
)


@app.on_event("startup")
async def startup_event() -> None:
    print("Loading data...")
    data_service.load_data()
    print("Warming up API caches...")
    data_service.get_dashboard_summary()
    data_service.get_filters()
    data_service.get_relativity_analytics()
    data_service.get_validation_report(sample_size=100, seed=42)
    print("Cache warming complete.")


@app.get("/api/health")
def health() -> dict:
    return data_service.get_health()


@app.get("/api/dashboard")
def dashboard() -> dict:
    return data_service.get_dashboard_summary()


@app.get("/api/filters")
def filters() -> dict:
    return data_service.get_filters()


@app.get("/api/articles")
def articles(
    page: int = Query(1, ge=1),
    limit: int = Query(25, ge=1, le=200),
    search: str = "",
    weave: str = "",
    blend: str = "",
    loom_type: str = "",
    dataset: str = "",
    count_band: str = "",
) -> dict:
    return data_service.get_articles(
        page, limit, search, weave, blend, loom_type, dataset, count_band,
    )


@app.get("/api/article/{master_article}")
def article(master_article: str) -> dict:
    return data_service.get_article_detail(master_article)


@app.get("/api/analytics/relativity")
def relativity() -> dict:
    return data_service.get_relativity_analytics()


@app.get("/api/process-flow")
def process_flow() -> dict:
    return data_service.get_process_flow()


@app.get("/api/documentation")
def documentation() -> dict:
    return data_service.get_documentation()


@app.get("/api/data-source/audit")
def data_source_audit() -> dict:
    return data_service.get_data_source_audit()


@app.get("/api/validation/report")
def validation_report(
    sample_size: int = Query(250, ge=30, le=2000), seed: int = 42,
) -> dict:
    return data_service.get_validation_report(sample_size=sample_size, seed=seed)


@app.post("/api/predictions/construction")
def predict(payload: dict) -> dict:
    return data_service.predict_construction(payload)


# ============== New endpoints ==============

@app.get("/api/count/available")
def available_counts() -> dict:
    return {
        "standard_ne": get_available_standard_counts(),
        "ply_yarns": get_available_ply_counts(),
    }


@app.get("/api/count/convert")
def count_convert(
    value: float = Query(...),
    from_unit: str = Query("ne"),
    to_unit: str = Query("denier"),
) -> dict:
    result = convert_count(value, from_unit, to_unit)
    return {
        "input": {"value": value, "unit": from_unit},
        "output": {"value": result, "unit": to_unit},
    }


@app.get("/api/count/nearest")
def nearest_counts(
    value: float = Query(...),
    n: int = Query(3, ge=1, le=10),
) -> dict:
    nearest = nearest_standard_counts(value, n)
    return {
        "input_value": value,
        "nearest_standard_ne": nearest,
    }


@app.get("/api/count/parse")
def parse_count(count_string: str = Query(...)) -> dict:
    result = parse_count_string(count_string)
    if result is None:
        return {"error": f"Could not parse: {count_string}"}
    return {"input": count_string, "parsed": result}


@app.get("/api/reed/ranges")
def reed_ranges(loom_type: str = Query("airjet")) -> dict:
    return {
        "loom_type": loom_type,
        "reed_counts": get_reed_range(loom_type),
        "all_airjet": get_reed_range("airjet"),
        "all_rapier": get_reed_range("rapier"),
    }


@app.post("/api/predictions/export-xml")
def export_xml(payload: dict):
    import io
    import xml.etree.ElementTree as ET
    from fastapi.responses import Response

    rec = payload.get("recommendation", {})
    inp = payload.get("input", {})

    def gv(key: str, fallback=0):
        val = rec.get(key)
        if val:
            try:
                return round(float(val), 2)
            except (ValueError, TypeError):
                return fallback
        return fallback

    w_cnt = gv("warp_count", inp.get("normalized_warp_count") or inp.get("raw_warp_count") or 0)
    wt_cnt = gv("weft_count", inp.get("normalized_weft_count") or inp.get("raw_weft_count") or 0)
    reed = gv("reed_count", 0)
    e_dent = gv("ends_per_dent", 0)
    r_space = gv("reed_space", 0)
    g_epi = gv("greige_epi", 0)
    g_ppi = gv("greige_ppi", 0)
    f_epi = gv("finish_epi", 0)
    f_ppi = gv("finish_ppi", 0)
    f_width = gv("finish_width", 0)

    blend = str(inp.get("blend", ""))
    weave = str(inp.get("weave", ""))

    root = ET.Element("PenelopeDesigns", Version="v1.12")
    fabric = ET.SubElement(root, "Fabric", Name="construction")
    fabric.set("Folder1", "BA")
    fabric.set("Folder2", "DS")
    fabric.set("Folder3", "2026")

    yarns = ET.SubElement(fabric, "Yarns")
    for yname, count, ylabel in [
        ("WARP_YARN", w_cnt, "WARP"),
        ("WEFT_YARN", wt_cnt, "WEFT"),
    ]:
        yarn = ET.SubElement(yarns, "Yarn", DataBaseId="0", Name=yname, Set="construction")
        ET.SubElement(yarn, "SecondName").text = ylabel
        ET.SubElement(yarn, "Count").text = f"{count} ne" if count else ""
        ET.SubElement(yarn, "Material").text = blend

    ends_total = int(g_epi * r_space * 0.0254 * 100) if g_epi and r_space else 0

    warp = ET.SubElement(fabric, "Warp", NEndsRepeat=str(ends_total), NColorWays="1", NColors="1", NBeams="1")
    cw_warp = ET.SubElement(warp, "ColorWay", Name="A")
    ET.SubElement(cw_warp, "Yarn", Id="0", DataBaseId="0", Set="construction", Name="WARP_YARN", NEnds=str(ends_total))

    weft = ET.SubElement(fabric, "Weft", NEndsRepeat="0", NColorWays="1", NColors="1")
    cw_weft = ET.SubElement(weft, "ColorWay", Name="A")
    ET.SubElement(cw_weft, "Yarn", Id="0", DataBaseId="0", Set="construction", Name="WEFT_YARN")

    ET.SubElement(fabric, "Weave", Name=f"{weave}.", Folder1="WEAVE", NEndsRepeat="0", NPicksRepeat="0")

    denting = ET.SubElement(fabric, "Denting", NDents=str(int(e_dent)), NEnds="4")
    ET.SubElement(denting, "Dents").text = f"{int(e_dent)}x{int(e_dent)}" if e_dent else "0"

    tech = ET.SubElement(fabric, "TechnicalData")
    reed_dens_cm = round(reed / 39.37, 1) if reed else 0
    ET.SubElement(tech, "ReedDensity", Value=str(reed), Unit="inch", ValueCm=str(reed_dens_cm))
    reed_width_cm = round(r_space * 2.54, 2) if r_space else 0
    ET.SubElement(tech, "ReedWidth", Value=str(r_space), Unit="inch", ValueCM=str(reed_width_cm))
    fin_wid_cm = round(f_width * 2.54, 2) if f_width else 0
    ET.SubElement(tech, "FinishedWidth", Value=str(f_width), Unit="inch", ValueCM=str(fin_wid_cm))
    ET.SubElement(tech, "FinishedWarpDensity", Value=str(f_epi), Unit="inch", ValueCm=str(round(f_epi / 39.37, 1)))
    ET.SubElement(tech, "WovenWarpDensity", Value=str(g_epi), Unit="inch", ValueCm=str(round(g_epi / 39.37, 1)))
    ET.SubElement(tech, "WeftDensity", Value=str(g_ppi), Unit="inch", ValueCm=str(round(g_ppi / 39.37, 1)))
    ET.SubElement(tech, "Composition", Warp=blend, Weft=blend, Total=blend)
    ET.SubElement(tech, "Comment", Weave=weave)

    tree = ET.ElementTree(root)
    ET.indent(tree, space="    ", level=0)
    out = io.BytesIO()
    tree.write(out, encoding="utf-8", xml_declaration=True)

    return Response(
        content=out.getvalue(),
        media_type="application/xml",
        headers={"Content-Disposition": "attachment; filename=construction.xml"},
    )


# Serve Next.js static frontend
FRONTEND_BUILD_DIR = os.path.join(
    os.path.dirname(os.path.abspath(__file__)), "..", "frontend", "out"
)
FRONTEND_BUILD_DIR = os.path.abspath(FRONTEND_BUILD_DIR)

if os.path.isdir(FRONTEND_BUILD_DIR):
    app.mount(
        "/", StaticFiles(directory=FRONTEND_BUILD_DIR, html=True), name="frontend"
    )
else:
    @app.get("/")
    def serve_frontend():
        return HTMLResponse(
            content="""
        <!DOCTYPE html>
        <html>
        <head>
            <title>PDC Intelligence</title>
            <meta charset="utf-8">
            <meta name="viewport" content="width=device-width, initial-scale=1">
            <script src="https://cdn.tailwindcss.com"></script>
        </head>
        <body class="bg-slate-50">
            <div class="p-8">
                <h1 class="text-2xl font-bold text-slate-800">PDC Intelligence</h1>
                <p class="text-slate-600 mt-2">Backend is running. API available at /api/*</p>
                <div class="mt-4 p-4 bg-white rounded-lg border border-slate-200">
                    <h2 class="font-semibold">Available Endpoints:</h2>
                    <ul class="mt-2 space-y-1 text-sm">
                        <li><code class="bg-slate-100 px-2 py-1">GET /api/health</code> - Health check</li>
                        <li><code class="bg-slate-100 px-2 py-1">GET /api/dashboard</code> - Dashboard summary</li>
                        <li><code class="bg-slate-100 px-2 py-1">GET /api/filters</code> - Available filters</li>
                        <li><code class="bg-slate-100 px-2 py-1">GET /api/articles</code> - Article search</li>
                        <li><code class="bg-slate-100 px-2 py-1">POST /api/predictions/construction</code> - Construction prediction</li>
                    </ul>
                </div>
            </div>
        </body>
        </html>
        """,
            status_code=200,
        )