// === GRAPH VIEW ===

let gSvg, gG, gZoom, gSim;

function renderGraphSidebar() {
    const el = document.getElementById("graph-sidebar");
    const nc = filterTags().length;
    const ec = state.graphEdges.length + state.treeEdges.length;

    el.innerHTML = `
        <div class="graph-stats">
            <div class="graph-stat">
                <div class="graph-stat-val">${nc}</div>
                <div class="graph-stat-label">Nodos</div>
            </div>
            <div class="graph-stat">
                <div class="graph-stat-val">${ec}</div>
                <div class="graph-stat-label">Edges</div>
            </div>
        </div>
        <h4>Categorias</h4>
        <div class="graph-filters">
            ${Object.entries(CATS).map(([k,v]) =>
                `<div class="graph-filter ${state.graphFilters.cats.has(k) ? "active" : ""}" data-cat="${k}">
                    <span class="dot" style="background:${v.color}"></span>${v.name}
                </div>`
            ).join("")}
        </div>
        <h4>Relaciones</h4>
        <div class="graph-filters">
            ${Object.entries(EDGE_COLORS).map(([k,v]) =>
                `<div class="graph-filter ${state.graphFilters.edges.has(k) ? "active" : ""}" data-edge="${k}">
                    <span class="dot" style="background:${v}"></span>${k}
                </div>`
            ).join("")}
        </div>
        <h4>Visualizacion</h4>
        <div style="margin:8px 0">
            <label><input type="checkbox" id="graph-show-img" ${state.graphSettings.showImg ? "checked" : ""}> Imagenes</label>
        </div>
        <div style="margin:8px 0">
            <label><input type="checkbox" id="graph-show-lbl" ${state.graphSettings.showLbl ? "checked" : ""}> Etiquetas</label>
        </div>
        <div style="margin:12px 0">
            <div style="color:var(--text-muted);margin-bottom:6px">Nodo: ${state.graphSettings.nodeSize}px</div>
            <input type="range" class="graph-slider" id="graph-node-size" min="10" max="50" value="${state.graphSettings.nodeSize}">
        </div>
        <div style="margin:12px 0">
            <div style="color:var(--text-muted);margin-bottom:6px">Distancia: ${state.graphSettings.linkDist}px</div>
            <input type="range" class="graph-slider" id="graph-link-dist" min="40" max="200" value="${state.graphSettings.linkDist}">
        </div>`;

    // Bind category filters
    el.querySelectorAll("[data-cat]").forEach(f => {
        f.onclick = () => {
            const c = f.dataset.cat;
            state.graphFilters.cats.has(c) ? state.graphFilters.cats.delete(c) : state.graphFilters.cats.add(c);
            initGraph();
        };
    });

    // Bind edge filters
    el.querySelectorAll("[data-edge]").forEach(f => {
        f.onclick = () => {
            const e = f.dataset.edge;
            state.graphFilters.edges.has(e) ? state.graphFilters.edges.delete(e) : state.graphFilters.edges.add(e);
            initGraph();
        };
    });

    // Bind settings
    document.getElementById("graph-show-img").onchange = e => {
        state.graphSettings.showImg = e.target.checked;
        updateGraphVisuals();
    };
    document.getElementById("graph-show-lbl").onchange = e => {
        state.graphSettings.showLbl = e.target.checked;
        updateGraphVisuals();
    };
    document.getElementById("graph-node-size").oninput = e => {
        state.graphSettings.nodeSize = +e.target.value;
        updateGraphVisuals();
    };
    document.getElementById("graph-link-dist").oninput = e => {
        state.graphSettings.linkDist = +e.target.value;
        if (gSim) {
            gSim.force("link").distance(state.graphSettings.linkDist);
            gSim.alpha(0.3).restart();
        }
    };
}

function renderGraphLegend() {
    document.getElementById("graph-legend").innerHTML = Object.entries(CATS)
        .filter(([k]) => state.graphFilters.cats.has(k))
        .map(([k,v]) => `<div class="legend-item"><div class="legend-color" style="background:${v.color}"></div>${v.name}</div>`)
        .join("");
}

function updateGraphVisuals() {
    if (!gG) return;
    const ns = state.graphSettings.nodeSize;

    gG.selectAll(".node circle").attr("r", ns);
    gG.selectAll(".node image")
        .attr("x", -ns+5)
        .attr("y", -ns+5)
        .attr("width", (ns-5)*2)
        .attr("height", (ns-5)*2)
        .style("display", state.graphSettings.showImg ? "block" : "none");
    gG.selectAll(".node text")
        .attr("dx", ns+5)
        .style("display", state.graphSettings.showLbl ? "block" : "none");

    renderGraphSidebar();
}

async function initGraph() {
    const container = document.getElementById("graph-view");
    const svg = document.getElementById("graph-svg");
    const w = container.clientWidth - 230;
    const h = container.clientHeight;

    if (gSim) gSim.stop();

    gSvg = d3.select(svg).attr("width", w + 230).attr("height", h);
    gSvg.selectAll("*").remove();
    gG = gSvg.append("g").attr("transform", "translate(230, 0)");

    gZoom = d3.zoom()
        .scaleExtent([0.05, 4])
        .on("zoom", e => gG.attr("transform", `translate(230, 0) ${e.transform}`));
    gSvg.call(gZoom);

    renderGraphSidebar();
    renderGraphLegend();

    // Fetch data if needed
    if (!state.graphEdges.length) await fetchGraphEdges();
    if (!state.treeEdges.length) await fetchTreeEdges();

    // Build nodes
    const filtered = filterTags();
    const nodes = filtered.map(t => {
        const grupo = t.set_hst || "hst";
        const groupInfo = state.groups.find(g => g.mrf === grupo);
        const cat = groupInfo?.ref || "hst";
        return { id: t.mrf, ref: t.ref || "", name: getName(t), img: getImg(t), cat };
    }).filter(n => state.graphFilters.cats.has(n.cat) || state.graphFilters.cats.has("hst"));

    if (!nodes.length) {
        gG.append("text")
            .attr("x", w/2)
            .attr("y", h/2)
            .attr("text-anchor", "middle")
            .attr("fill", "#666")
            .text("Sin datos - activa categorias");
        return;
    }

    // Build edges
    const nodeIds = new Set(nodes.map(n => n.id));
    const edges = [];

    state.graphEdges.forEach(e => {
        const t = e.edge_type || "relation";
        if (state.graphFilters.edges.has(t) && nodeIds.has(e.mrf_a) && nodeIds.has(e.mrf_b)) {
            edges.push({source: e.mrf_a, target: e.mrf_b, type: t, weight: e.weight || 0.5});
        }
    });

    if (state.graphFilters.edges.has("hierarchy")) {
        state.treeEdges.forEach(e => {
            if (nodeIds.has(e.mrf_parent) && nodeIds.has(e.mrf_child)) {
                edges.push({source: e.mrf_parent, target: e.mrf_child, type: "hierarchy", weight: 0.8});
            }
        });
    }

    // Create simulation
    const ns = state.graphSettings.nodeSize;
    gSim = d3.forceSimulation(nodes)
        .force("link", d3.forceLink(edges).id(d => d.id).distance(state.graphSettings.linkDist))
        .force("charge", d3.forceManyBody().strength(-150))
        .force("center", d3.forceCenter(w/2, h/2))
        .force("collision", d3.forceCollide(ns + 4));

    // Draw links
    const link = gG.append("g")
        .selectAll("line")
        .data(edges)
        .enter()
        .append("line")
        .attr("stroke", d => EDGE_COLORS[d.type] || "#333")
        .attr("stroke-width", d => Math.max(1.5, d.weight * 3))
        .attr("class", "link");

    // Draw nodes
    const node = gG.append("g")
        .selectAll("g")
        .data(nodes)
        .enter()
        .append("g")
        .attr("class", d => `node ${state.selected.has(d.id) ? "selected" : ""}`)
        .call(d3.drag()
            .on("start", (e,d) => {
                if (!e.active) gSim.alphaTarget(0.3).restart();
                d.fx = d.x; d.fy = d.y;
            })
            .on("drag", (e,d) => { d.fx = e.x; d.fy = e.y; })
            .on("end", (e,d) => {
                if (!e.active) gSim.alphaTarget(0);
                d.fx = null; d.fy = null;
            })
        );

    node.append("circle")
        .attr("r", ns)
        .attr("fill", d => CATS[d.cat]?.color || "#7c8aff")
        .attr("stroke", d => state.selected.has(d.id) ? "var(--accent)" : "#1a1a24")
        .attr("stroke-width", d => state.selected.has(d.id) ? 4 : 2);

    node.filter(d => d.img && state.graphSettings.showImg)
        .append("image")
        .attr("href", d => d.img)
        .attr("x", -ns+5)
        .attr("y", -ns+5)
        .attr("width", (ns-5)*2)
        .attr("height", (ns-5)*2)
        .attr("clip-path", "circle(50%)");

    node.append("text")
        .attr("dx", ns+5)
        .attr("dy", 4)
        .text(d => d.ref)
        .style("display", state.graphSettings.showLbl ? "block" : "none");

    node.on("click", (e,d) => state.selectionMode ? toggleSel(d.id) : showDetail(d.id));

    // Tick handler
    gSim.on("tick", () => {
        link
            .attr("x1", d => d.source.x)
            .attr("y1", d => d.source.y)
            .attr("x2", d => d.target.x)
            .attr("y2", d => d.target.y);
        node.attr("transform", d => `translate(${d.x},${d.y})`);
    });

    // Controls
    document.getElementById("graph-fit").onclick = () => {
        const b = gG.node().getBBox();
        if (b.width) {
            const s = Math.min((w-100)/b.width, (h-100)/b.height, 2);
            gSvg.transition().call(gZoom.transform,
                d3.zoomIdentity
                    .translate(w/2-(b.x+b.width/2)*s+230, h/2-(b.y+b.height/2)*s)
                    .scale(s)
            );
        }
    };
    document.getElementById("graph-zin").onclick = () => gSvg.transition().call(gZoom.scaleBy, 1.5);
    document.getElementById("graph-zout").onclick = () => gSvg.transition().call(gZoom.scaleBy, 0.67);
}