window.requestAnimFrame = (function () {
  return window.requestAnimationFrame
    || window.webkitRequestAnimationFrame
    || window.mozRequestAnimationFrame
    || function (callback) { window.setTimeout(callback, 1000 / 60); };
})();

(() => {
  let video;
  if (elem = document.querySelector("#my-video")) {
    video = new v0ck(elem);
    document.addEventListener("keydown", e => {
      if (e.key === " " && e.target.tagName !== "INPUT" && e.target.tagName !== "TEXTAREA") {
        video[video.paused ? 'play' : 'pause']();
        document.querySelector('.v0ck_overlay').classList[video.paused ? 'remove' : 'add']('v0ck_hidden');
      }
    });

    const toggleBg = document.getElementById('togglebg');
    if (toggleBg) {
      toggleBg.addEventListener('click', function (e) {
        e.preventDefault();
        background = !background;
        localStorage.setItem('background', background.toString());
        var canvas = document.getElementById('bg');
        if (background) {
          canvas.classList.add('fader-in');
          canvas.classList.remove('fader-out');
        } else {
          canvas.classList.add('fader-out');
          canvas.classList.remove('fader-in');
        }
        animationLoop();
      });
    }

    if (elem !== null) {
      if (localStorage.getItem('background') == undefined) {
        localStorage.setItem('background', 'true');
      }

      var background = localStorage.getItem('background') === 'true';
      var canvas = document.getElementById('bg');
      if (canvas) {
        var context = canvas.getContext('2d');
        var cw = canvas.width = canvas.clientWidth | 0;
        var ch = canvas.height = canvas.clientHeight | 0;

        function animationLoop() {
          if (video.paused || video.ended || !background)
            return;
          context.drawImage(video, 0, 0, cw, ch);
          window.requestAnimFrame(animationLoop);
        }

        elem.addEventListener('play', animationLoop);
      }
    }
  }

  let tt = false;
  const stimeout = 500;

  const setupMedia = () => {
    if (elem = document.querySelector("#my-video")) {
      video = new v0ck(elem);
    }
  };

  const loadItemAjax = async (url, inheritContext = true) => {
    console.log("loadItemAjax called with:", url, "inheritContext:", inheritContext);
    // Show loading indicator
    const navbar = document.querySelector("nav.navbar");
    if (navbar) navbar.classList.add("pbwork");

    // Extract item ID from URL. Regex now handles query params, hashes, and trailing slashes.
    const match = url.match(/\/(\d+)(?:\/|#|\?|$)/);

    if (!match) {
      console.warn("loadItemAjax: No ID match found in URL", url);
      // fallback for weird/external links
      window.location.href = url;
      return;
    }
    const itemid = match[1];

    // <context-preservation>
    // Extract context from Target URL first
    let tag = null, user = null;
    const tagMatch = url.match(/\/tag\/([^/]+)/);
    if (tagMatch) tag = decodeURIComponent(tagMatch[1]);

    const userMatch = url.match(/\/user\/([^/]+)/);
    if (userMatch) user = decodeURIComponent(userMatch[1]); // Note: "user" variable shadowed? No, block scope or different name? let user defined above.

    // If missing and inheritContext is true, check Window Location
    if (inheritContext) {
      if (!tag) {
        const wTagMatch = window.location.href.match(/\/tag\/([^/]+)/);
        if (wTagMatch) tag = decodeURIComponent(wTagMatch[1]);
      }
      if (!user) {
        const wUserMatch = window.location.href.match(/\/user\/([^/]+)/);
        if (wUserMatch) user = decodeURIComponent(wUserMatch[1]);
      }
    }
    // </context-preservation>

    try {
      // Construct AJAX URL
      let ajaxUrl = `/ajax/item/${itemid}`;

      const params = new URLSearchParams();
      if (tag) params.append('tag', tag);
      if (user) params.append('user', user);

      if ([...params].length > 0) {
        ajaxUrl += '?' + params.toString();
      }

      console.log("Fetching:", ajaxUrl);
      const response = await fetch(ajaxUrl);
      if (!response.ok) throw new Error(`Network response was not ok: ${response.status}`);

      const rawText = await response.text();
      let html, paginationHtml;

      try {
        // Optimistically try to parse as JSON first
        const data = JSON.parse(rawText);
        if (data && typeof data.html === 'string') {
          html = data.html;
          paginationHtml = data.pagination;
        } else {
          html = rawText;
        }
      } catch (e) {
        // If JSON parse fails, assume it's HTML text
        html = rawText;
      }

      let container = document.querySelector('.container');

      if (!container && document.querySelector('.index-container')) {
        // Transition from Index to Item View
        const main = document.getElementById('main');
        main.innerHTML = '<div class="container"></div>';
        container = main.querySelector('.container');
      } else if (container) {
        // Already in Item View, clear usage
        const oldContent = container.querySelector('.content');
        const oldMetadata = container.querySelector('.metadata');
        const oldHeader = container.querySelector('._204863');
        if (oldHeader) oldHeader.remove();
        if (oldContent) oldContent.remove();
        if (oldMetadata) oldMetadata.remove();
      }

      container.insertAdjacentHTML('beforeend', html);

      // Update pagination if present
      if (paginationHtml) {
        const pagWrappers = document.querySelectorAll('.pagination-wrapper');
        pagWrappers.forEach(el => el.innerHTML = paginationHtml);
      }

      // Construct proper History URL (Context Aware)
      // If we inherited context, we should reflect it in the URL
      let pushUrl = `/${itemid}`;
      // Logic from ajax.mjs context reconstruction:
      if (user) pushUrl = `/user/${user}/${itemid}`; // User takes precedence usually? Or strictly mutually exclusive in UI
      else if (tag) pushUrl = `/tag/${tag}/${itemid}`;

      // We overwrite proper URL even if the link clicked was "naked"
      history.pushState({}, '', pushUrl);

      setupMedia();
      // Try to extract ID from response if possible or just use itemid
      document.title = `f0bm - ${itemid}`;
      if (navbar) navbar.classList.remove("pbwork");
      console.log("AJAX load complete");

    } catch (err) {
      console.error("AJAX load failed:", err);
    }
  };

  const changePage = (e, pbwork = true) => {
    if (e.tagName === 'A') {
      e.preventDefault();
      loadItemAjax(e.href);
    } else {
      pbwork && document.querySelector("nav.navbar").classList.add("pbwork");
      !tt && (tt = setTimeout(() => e.click(), stimeout));
    }
  };

  // Intercept clicks
  document.addEventListener('click', (e) => {

    // Check for thumbnail links on index page
    const thumbnail = e.target.closest('.posts > a');
    if (thumbnail && !e.ctrlKey && !e.shiftKey && !e.altKey && !e.metaKey) {
      e.preventDefault();
      // Thumbnails inherit context (e.g. from Tag Index)
      loadItemAjax(thumbnail.href, true);
      return;
    }

    const link = e.target.closest('#next, #prev, #random, .id-link, .nav-next, .nav-prev');
    if (link && link.href && link.hostname === window.location.hostname && !e.ctrlKey && !e.shiftKey && !e.altKey && !e.metaKey) {
      // Special check for random
      if (link.id === 'random') {
        e.preventDefault();
        const nav = document.querySelector("nav.navbar");
        if (nav) nav.classList.add("pbwork");

        // Extract current context from window location
        let randomUrl = '/api/v2/random';
        const params = new URLSearchParams();

        const wTagMatch = window.location.href.match(/\/tag\/([^/]+)/);
        if (wTagMatch) params.append('tag', decodeURIComponent(wTagMatch[1]));

        const wUserMatch = window.location.href.match(/\/user\/([^/]+)/);
        if (wUserMatch) params.append('user', decodeURIComponent(wUserMatch[1]));

        if ([...params].length > 0) {
          randomUrl += '?' + params.toString();
        }

        fetch(randomUrl)
          .then(r => r.json())
          .then(data => {
            if (data.success && data.items && data.items.id) {
              // Inherit context so URL matches current filter
              loadItemAjax(`/${data.items.id}`, true);
            } else {
              window.location.href = link.href;
            }
          })
          .catch(() => window.location.href = link.href);
        return;
      }

      // Standard item links
      e.preventDefault();
      loadItemAjax(link.href, true);
    }
  });

  window.addEventListener('popstate', (e) => {
    loadItemAjax(window.location.href, true);
  });

  // <keybindings>
  const clickOnElementBinding = selector => () => (elem = document.querySelector(selector)) ? elem.click() : null;
  const keybindings = {
    "ArrowLeft": clickOnElementBinding("#next"),
    "a": clickOnElementBinding("#next"),
    "ArrowRight": clickOnElementBinding("#prev"),
    "d": clickOnElementBinding("#prev"),
    "r": clickOnElementBinding("#random"),
    " ": clickOnElementBinding("#f0ck-image")
  };
  document.addEventListener("keydown", e => {
    if (e.key in keybindings && e.target.tagName !== "INPUT" && e.target.tagName !== "TEXTAREA") {
      if (e.shiftKey || e.ctrlKey || e.metaKey || e.altKey)
        return;
      e.preventDefault();
      keybindings[e.key]();
    }
  });
  // </keybindings>

  // <image-responsive>
  const imgSize = e => new Promise((res, _) => {
    const i = new Image();
    i.addEventListener('load', function () {
      res({ width: this.width, height: this.height });
    });
    i.src = e.src;
  });

  // <wheeler>
  const wheelEventListener = function (event) {
    if (event.target.closest('.media-object, .steuerung')) {
      if (event.deltaY < 0) {
        const el = document.getElementById('next');
        if (el && el.href && !el.href.endsWith('#')) el.click();
      } else if (event.deltaY > 0) {
        const el = document.getElementById('prev');
        if (el && el.href && !el.href.endsWith('#')) el.click();
      }
    }
  };

  window.addEventListener('wheel', wheelEventListener);
  // </wheeler>


  if (f0ckimage = document.querySelector("img#f0ck-image")) {
    const f0ckimagescroll = document.querySelector("#image-scroll");

    let isImageExpanded = false;
    console.log("entry point - image unclicked")

    f0ckimage.addEventListener("click", async e => {
      e.preventDefault();
      const img = await imgSize(f0ckimage);
      console.log("img clicked");
      if (isImageExpanded) {
        isImageExpanded = false;
        f0ckimagescroll.removeAttribute("style");
        f0ckimage.removeAttribute("style");
        console.log("image is not expanded")
        window.addEventListener('wheel', wheelEventListener);
      } else {
        if (img.width > img.height) return;
        isImageExpanded = true;
        window.removeEventListener('wheel', wheelEventListener);
        f0ckimagescroll.setAttribute("style", "overflow-y: scroll");
        f0ckimage.setAttribute("style", "max-height: none; height: auto; width: 100%; position: absolute; left: 0; border: var(--img-border-width) solid var(--img-border-color); border-top: none; border-bottom: none;");
      }
    });
  }
  // </image-responsive>

  // <scroller>
  let tts = 0;
  const scroll_treshold = 1;
  if ([...document.querySelectorAll("div.posts")].length === 1) {
    document.addEventListener("wheel", e => {
      if (!document.querySelector('#main')) return;

      if (Math.ceil(window.innerHeight + window.scrollY) >= document.querySelector('#main').offsetHeight && e.deltaY > 0) { // down
        if (elem = document.querySelector(".pagination > .next:not(.disabled)")) {
          if (tts < scroll_treshold) {
            const foot = document.querySelector("div#footbar");
            if (foot) {
              foot.style.boxShadow = "inset 0px 4px 0px var(--footbar-color)";
              foot.style.color = "var(--footbar-color)";
            }
            tts++;
          }
          else
            changePage(elem);
        }
      }
      else if (window.scrollY <= 0 && e.deltaY < 0) { // up
        if (elem = document.querySelector(".pagination > .prev:not(.disabled)")) {
          if (tts < scroll_treshold) {
            const nav = document.querySelector("nav.navbar");
            if (nav) {
              nav.style.boxShadow = "0px 2px 0px var(--loading-indicator-color)";
              nav.style.transition = ".2s ease-in-out";
            }
            tts++;
          }
          else
            changePage(elem);
        }
      }
      else {
        tts = 0;
        const foot = document.querySelector("div#footbar");
        if (foot) {
          foot.style.boxShadow = "unset";
          foot.style.color = "transparent";
        }
        const nav = document.querySelector("nav.navbar");
        if (nav) nav.style.boxShadow = "unset";
      }
    });
  }

  const rmatch = /\/p\/(\d+?)/;
  if (document.referrer.match(rmatch) && document.location.href.match(rmatch))
    if (document.location.href.match(rmatch) < document.referrer.match(rmatch))
      document.body.scrollTop = document.body.scrollHeight;
  // </scroller>

  // <swipe>
  const swipeRT = {
    xDown: null,
    yDown: null,
    xDiff: null,
    yDiff: null,
    timeDown: null,
    startEl: null
  };
  const swipeOpt = {
    treshold: 20, // 20px
    timeout: 500  // 500ms
  };

  document.addEventListener('touchstart', e => {
    swipeRT.startEl = e.target;
    swipeRT.timeDown = Date.now();
    swipeRT.xDown = e.touches[0].clientX;
    swipeRT.yDown = e.touches[0].clientY;
    swipeRT.xDiff = 0;
    swipeRT.yDiff = 0;
  }, false);

  document.addEventListener('touchmove', e => {
    if (!swipeRT.xDown || !swipeRT.yDown)
      return;
    swipeRT.xDiff = swipeRT.xDown - e.touches[0].clientX;
    swipeRT.yDiff = swipeRT.yDown - e.touches[0].clientY;
  }, false);

  document.addEventListener('touchend', e => {
    if (swipeRT.startEl !== e.target)
      return;

    const timeDiff = Date.now() - swipeRT.timeDown;
    let elem;

    if (Math.abs(swipeRT.xDiff) > Math.abs(swipeRT.yDiff)) {
      if (Math.abs(swipeRT.xDiff) > swipeOpt.treshold && timeDiff < swipeOpt.timeout) {
        if (swipeRT.xDiff > 0) // left
          elem = document.querySelector(".pagination > .next:not(.disabled)");
        else // right
          elem = document.querySelector(".pagination > .prev:not(.disabled)");
      }
    }
    else {
      if (Math.abs(swipeRT.yDiff) > swipeOpt.treshold && timeDiff < swipeOpt.timeout) {
        if (navbar = document.querySelector("nav.navbar") && document.querySelector("div.posts")) {
          if (swipeRT.yDiff > 0 && (window.innerHeight + window.scrollY) >= document.body.offsetHeight) // up
            elem = document.querySelector(".pagination > .next:not(.disabled)");
          else if (swipeRT.yDiff <= 0 && window.scrollY <= 0 && document.querySelector("div.posts")) // down
            elem = document.querySelector(".pagination > .prev:not(.disabled)");
        }
      }
    }

    swipeRT.xDown = null;
    swipeRT.yDown = null;
    swipeRT.timeDown = null;

    if (elem)
      changePage(elem);
  }, false);
  // </swipe>

  // <visualizer>
  if (audioElement = document.querySelector("audio")) {
    const canvas = document.createElement("canvas");
    const ctx = canvas.getContext("2d");
    canvas.width = 1920;
    canvas.height = 1080;

    setTimeout(() => {
      document.querySelector(".v0ck").insertAdjacentElement("afterbegin", canvas);
    }, 400);

    const audioCtx = new AudioContext();
    const analyser = audioCtx.createAnalyser();
    analyser.fftSize = 2048;

    const source = audioCtx.createMediaElementSource(audioElement);
    source.connect(analyser);
    source.connect(audioCtx.destination);

    let data = new Uint8Array(analyser.frequencyBinCount);
    requestAnimationFrame(loopingFunction);

    function loopingFunction() {
      requestAnimationFrame(loopingFunction);
      analyser.getByteFrequencyData(data);
      draw(data);
    }
    function draw(data) {
      data = [...data];
      ctx.clearRect(0, 0, canvas.width, canvas.height);
      ctx.fillStyle = getComputedStyle(document.body).getPropertyValue("--accent");
      data.forEach((value, i) => {
        const percent = value / 256;
        const height = (canvas.height * percent / 2) - 40;
        const offset = canvas.height - height - 1;
        const barWidth = canvas.width / analyser.frequencyBinCount;
        ctx.fillRect(i * barWidth, offset, barWidth, height);
      });
    }
    audioElement.onplay = () => {
      audioCtx.resume();
    };
  }
  // </visualizer>

  // <mediakeys>
  if (elem = document.querySelector("#my-video") && "mediaSession" in navigator) {
    const playpauseEvent = () => {
      video[video.paused ? 'play' : 'pause']();
      document.querySelector('.v0ck_overlay').classList[video.paused ? 'remove' : 'add']('v0ck_hidden');
    };
    navigator.mediaSession.setActionHandler('play', playpauseEvent);
    navigator.mediaSession.setActionHandler('pause', playpauseEvent);
    navigator.mediaSession.setActionHandler('stop', playpauseEvent);
    navigator.mediaSession.setActionHandler('previoustrack', () => {
      if (link = document.querySelector(".pagination > .prev:not(.disabled)"))
        changePage(link);
    });
    navigator.mediaSession.setActionHandler('nexttrack', () => {
      if (link = document.querySelector(".pagination > .next:not(.disabled)"))
        changePage(link);
    });
  }
  // </mediakeys>

  // <scroller>

  // </scroller>
})();

// disable default scroll event when mouse is on content div
// this is useful for items that have a lot of tags for example: 12536
const targetSelector = '.content';
let isMouseOver = true;

function isPageScrollable() {
  return document.documentElement.scrollHeight > document.documentElement.clientHeight;
}

function onWheel(e) {
  if (isMouseOver && isPageScrollable()) {
    e.preventDefault();
  }
}

function init() {
  const el = document.querySelector(targetSelector);
  if (!el) return;
  el.addEventListener('mouseenter', () => isMouseOver = true);
  el.addEventListener('mouseleave', () => isMouseOver = false);
  window.addEventListener('wheel', onWheel, { passive: false });
}

window.addEventListener('load', init);

document.getElementById('sbtForm').addEventListener('submit', (e) => {
  e.preventDefault();
  const input = document.getElementById('sbtInput').value.trim();
  if (input) {
    window.location.href = `/tag/${encodeURIComponent(input)}`;
  }
});