import cytoscape from "cytoscape";
import cxtmenu from "cytoscape-cxtmenu";
import klay from "cytoscape-klay";

cytoscape.use(klay);
cytoscape.use(cxtmenu);

async function getGraphData(url, godfathersDepth, godchildrenDepth) {
  const data = await (
    await fetch(
      `${url}?godfathers_depth=${godfathersDepth}&godchildren_depth=${godchildrenDepth}`,
    )
  ).json();
  return [
    ...data.users.map((user) => {
      return { data: user };
    }),
    ...data.relationships.map((rel) => {
      return {
        data: { source: rel.godfather, target: rel.godchild },
      };
    }),
  ];
}

function createGraph(container, data, activeUserId) {
  const cy = cytoscape({
    boxSelectionEnabled: false,
    autounselectify: true,

    container,
    elements: data,
    minZoom: 0.5,

    style: [
      // the stylesheet for the graph
      {
        selector: "node",
        style: {
          label: "data(display_name)",
          "background-image": "data(profile_pict)",
          width: "100%",
          height: "100%",
          "background-fit": "cover",
          "background-repeat": "no-repeat",
          shape: "ellipse",
        },
      },

      {
        selector: "edge",
        style: {
          width: 5,
          "line-color": "#ccc",
          "target-arrow-color": "#ccc",
          "target-arrow-shape": "triangle",
          "curve-style": "bezier",
        },
      },

      {
        selector: ".traversed",
        style: {
          "border-width": "5px",
          "border-style": "solid",
          "border-color": "red",
          "target-arrow-color": "red",
          "line-color": "red",
        },
      },

      {
        selector: ".not-traversed",
        style: {
          "line-opacity": "0.5",
          "background-opacity": "0.5",
          "background-image-opacity": "0.5",
        },
      },
    ],
    layout: {
      name: "klay",
      nodeDimensionsIncludeLabels: true,
      fit: true,
      klay: {
        addUnnecessaryBendpoints: true,
        direction: "DOWN",
        nodePlacement: "INTERACTIVE",
        layoutHierarchy: true,
      },
    },
  });
  const activeUser = cy.getElementById(activeUserId).style("shape", "rectangle");
  /* Reset graph */
  const resetGraph = () => {
    cy.elements((element) => {
      if (element.hasClass("traversed")) {
        element.removeClass("traversed");
      }
      if (element.hasClass("not-traversed")) {
        element.removeClass("not-traversed");
      }
    });
  };

  const onNodeTap = (el) => {
    resetGraph();
    /* Create path on graph if selected isn't the targeted user */
    if (el === activeUser) {
      return;
    }
    cy.elements((element) => {
      element.addClass("not-traversed");
    });

    for (const traversed of cy.elements().aStar({
      root: el,
      goal: activeUser,
    }).path) {
      traversed.removeClass("not-traversed");
      traversed.addClass("traversed");
    }
  };

  cy.on("tap", "node", (tapped) => {
    onNodeTap(tapped.target);
  });
  cy.zoomingEnabled(false);

  /* Add context menu */
  cy.cxtmenu({
    selector: "node",

    commands: [
      {
        content: '<i class="fa fa-external-link fa-2x"></i>',
        select: (el) => {
          window.open(el.data().profile_url, "_blank").focus();
        },
      },

      {
        content: '<span class="fa fa-mouse-pointer fa-2x"></span>',
        select: (el) => {
          onNodeTap(el);
        },
      },

      {
        content: '<i class="fa fa-eraser fa-2x"></i>',
        select: (_) => {
          resetGraph();
        },
      },
    ],
  });

  return cy;
}

/**
 * @typedef FamilyGraphConfig
 * @param {string} apiUrl Base url for fetching the tree as a string
 * @param {string} activeUser Id of the user to fetch the tree from
 * @param {number} depthMin Minimum tree depth for godfathers and godchildren
 * @param {number} depthMax Maximum tree depth for godfathers and godchildren
 **/

/**
 * Create a family graph of an user
 * @param {FamilyGraphConfig} Configuration
 **/
window.loadFamilyGraph = (config) => {
  document.addEventListener("alpine:init", () => {
    const defaultDepth = 2;

    function getInitialDepth(prop) {
      // biome-ignore lint/correctness/noUndeclaredVariables: defined by script.js
      const value = Number.parseInt(initialUrlParams.get(prop));
      if (Number.isNaN(value) || value < config.depthMin || value > config.depthMax) {
        return defaultDepth;
      }
      return value;
    }

    Alpine.data("graph", () => ({
      loading: false,
      godfathersDepth: getInitialDepth("godfathersDepth"),
      godchildrenDepth: getInitialDepth("godchildrenDepth"),
      // biome-ignore lint/correctness/noUndeclaredVariables: defined by script.js
      reverse: initialUrlParams.get("reverse")?.toLowerCase?.() === "true",
      graph: undefined,
      graphData: {},

      async init() {
        const delayedFetch = Alpine.debounce(async () => {
          await this.fetchGraphData();
        }, 100);
        for (const param of ["godfathersDepth", "godchildrenDepth"]) {
          this.$watch(param, async (value) => {
            if (value < config.depthMin || value > config.depthMax) {
              return;
            }
            // biome-ignore lint/correctness/noUndeclaredVariables: defined by script.js
            updateQueryString(param, value, History.REPLACE);
            await delayedFetch();
          });
        }
        this.$watch("reverse", async (value) => {
          // biome-ignore lint/correctness/noUndeclaredVariables: defined by script.js
          updateQueryString("reverse", value, History.REPLACE);
          await this.reverseGraph();
        });
        this.$watch("graphData", async () => {
          this.generateGraph();
          if (this.reverse) {
            await this.reverseGraph();
          }
        });
        await this.fetchGraphData();
      },

      screenshot() {
        const link = document.createElement("a");
        link.href = this.graph.jpg();
        link.download = interpolate(
          gettext("family_tree.%(extension)s"),
          { extension: "jpg" },
          true,
        );
        document.body.appendChild(link);
        link.click();
        document.body.removeChild(link);
      },

      reset() {
        this.reverse = false;
        this.godfathersDepth = defaultDepth;
        this.godchildrenDepth = defaultDepth;
      },

      async reverseGraph() {
        this.graph.elements((el) => {
          el.position({ x: -el.position().x, y: -el.position().y });
        });
        this.graph.center(this.graph.elements());
      },

      async fetchGraphData() {
        this.graphData = await getGraphData(
          config.apiUrl,
          this.godfathersDepth,
          this.godchildrenDepth,
        );
      },

      generateGraph() {
        this.loading = true;
        this.graph = createGraph(
          $(this.$refs.graph),
          this.graphData,
          config.activeUser,
        );
        this.loading = false;
      },
    }));
  });
};