// Video management: loading, unloading, first frame capture, depth handling
APP.core.video = {};

APP.core.video.captureFirstFrame = async function () {
    const { state } = APP.core;
    const { $ } = APP.core.utils;
    const videoHidden = $("#videoHidden");

    if (!videoHidden || !state.videoUrl) return;

    videoHidden.src = state.videoUrl;
    videoHidden.load();

    await new Promise((resolve, reject) => {
        videoHidden.onloadeddata = resolve;
        videoHidden.onerror = () => reject(new Error("Video failed to load"));
        setTimeout(() => reject(new Error("Video load timeout")), 10000);
    });

    // Seek to first frame
    videoHidden.currentTime = 0;
    await new Promise(r => {
        videoHidden.onseeked = r;
        setTimeout(r, 500);
    });

    state.frame.w = videoHidden.videoWidth || 1280;
    state.frame.h = videoHidden.videoHeight || 720;
};

APP.core.video.drawFirstFrame = function () {
    const { state } = APP.core;
    const { $ } = APP.core.utils;
    const frameCanvas = $("#frameCanvas");
    const frameOverlay = $("#frameOverlay");
    const videoHidden = $("#videoHidden");
    const frameEmpty = $("#frameEmpty");

    if (!frameCanvas || !videoHidden) return;

    const ctx = frameCanvas.getContext("2d");
    frameCanvas.width = state.frame.w;
    frameCanvas.height = state.frame.h;
    ctx.drawImage(videoHidden, 0, 0, state.frame.w, state.frame.h);

    // Also resize overlay to match so bbox coordinates align
    if (frameOverlay) {
        frameOverlay.width = state.frame.w;
        frameOverlay.height = state.frame.h;
    }

    if (frameEmpty) frameEmpty.style.display = "none";
};

APP.core.video.frameToBitmap = async function (videoEl) {
    const w = videoEl.videoWidth || 1280;
    const h = videoEl.videoHeight || 720;
    const canvas = document.createElement("canvas");
    canvas.width = w;
    canvas.height = h;
    const ctx = canvas.getContext("2d");
    ctx.drawImage(videoEl, 0, 0, w, h);
    return canvas;
};

APP.core.video.seekTo = function (videoEl, time) {
    return new Promise((resolve) => {
        if (!videoEl) { resolve(); return; }
        videoEl.currentTime = Math.max(0, time);
        videoEl.onseeked = () => resolve();
        setTimeout(resolve, 600);
    });
};

APP.core.video.unloadVideo = async function (options = {}) {
    const { state } = APP.core;
    const { $, $$ } = APP.core.utils;
    const { log, setStatus, setHfStatus } = APP.ui.logging;
    const preserveInput = !!options.preserveInput;

    // Stop polling if running
    if (state.hf.asyncPollInterval) {
        clearInterval(state.hf.asyncPollInterval);
        state.hf.asyncPollInterval = null;
    }

    // Revoke blob URLs
    if (state.videoUrl && state.videoUrl.startsWith("blob:")) {
        URL.revokeObjectURL(state.videoUrl);
    }
    if (state.hf.processedUrl && state.hf.processedUrl.startsWith("blob:")) {
        try { URL.revokeObjectURL(state.hf.processedUrl); } catch (_) { }
    }
    if (state.hf.depthVideoUrl && state.hf.depthVideoUrl.startsWith("blob:")) {
        try { URL.revokeObjectURL(state.hf.depthVideoUrl); } catch (_) { }
    }
    if (state.hf.depthFirstFrameUrl && state.hf.depthFirstFrameUrl.startsWith("blob:")) {
        try { URL.revokeObjectURL(state.hf.depthFirstFrameUrl); } catch (_) { }
    }

    // Reset state
    state.videoUrl = null;
    state.videoFile = null;
    state.videoLoaded = false;
    state.useProcessedFeed = false;
    state.useDepthFeed = false;
    state.useFrameDepthView = false;

    state.hf.missionId = null;
    state.hf.plan = null;
    state.hf.processedUrl = null;
    state.hf.processedBlob = null;
    state.hf.depthVideoUrl = null;
    state.hf.depthBlob = null;
    state.hf.depthFirstFrameUrl = null;
    state.hf.depthFirstFrameBlob = null;
    state.hf.summary = null;
    state.hf.busy = false;
    state.hf.lastError = null;
    state.hf.asyncJobId = null;
    state.hf.asyncStatus = "idle";
    state.hf.firstFrameUrl = null;
    state.hf.videoUrl = null;

    setHfStatus("idle");
    state.hasReasoned = false;
    state.firstFrameReady = false;
    state.isReasoning = false;

    // Reset button states
    const btnReason = $("#btnReason");
    const btnCancelReason = $("#btnCancelReason");
    const btnEngage = $("#btnEngage");

    if (btnReason) {
        btnReason.disabled = false;
        btnReason.style.opacity = "1";
        btnReason.style.cursor = "pointer";
    }
    if (btnCancelReason) btnCancelReason.style.display = "none";
    if (btnEngage) btnEngage.disabled = true;

    state.detections = [];
    state.selectedId = null;

    state.tracker.tracks = [];
    state.tracker.nextId = 1;
    state.tracker.running = false;
    state.tracker.selectedTrackId = null;
    state.tracker.beamOn = false;

    // Clear video elements
    const videoHidden = $("#videoHidden");
    const videoEngage = $("#videoEngage");
    const videoFile = $("#videoFile");

    if (videoHidden) {
        videoHidden.removeAttribute("src");
        videoHidden.load();
    }
    if (videoEngage) {
        videoEngage.removeAttribute("src");
        videoEngage.load();
    }
    if (!preserveInput && videoFile) {
        videoFile.value = "";
    }

    // Update UI
    const videoMeta = $("#videoMeta");
    const frameEmpty = $("#frameEmpty");
    const engageEmpty = $("#engageEmpty");
    const frameNote = $("#frameNote");
    const engageNote = $("#engageNote");

    if (!preserveInput && videoMeta) videoMeta.textContent = "No file";
    if (frameEmpty) frameEmpty.style.display = "flex";
    if (engageEmpty) engageEmpty.style.display = "flex";
    if (frameNote) frameNote.textContent = "Awaiting video";
    if (engageNote) engageNote.textContent = "Awaiting video";

    // Clear canvases
    APP.core.video.clearCanvas($("#frameCanvas"));
    APP.core.video.clearCanvas($("#frameOverlay"));
    APP.core.video.clearCanvas($("#engageOverlay"));

    // Re-render UI components
    if (APP.ui.radar.renderFrameRadar) APP.ui.radar.renderFrameRadar();
    if (APP.ui.cards.renderFrameTrackList) APP.ui.cards.renderFrameTrackList();
    if (APP.ui.trade.renderTrade) APP.ui.trade.renderTrade();

    setStatus("warn", "STANDBY · No video loaded");
    log("Video unloaded. Demo reset.", "w");
};

APP.core.video.clearCanvas = function (canvas) {
    if (!canvas) return;
    const ctx = canvas.getContext("2d");
    ctx.clearRect(0, 0, canvas.width, canvas.height);
};

APP.core.video.resizeOverlays = function () {
    const { state } = APP.core;
    const { $ } = APP.core.utils;

    const videoEngage = $("#videoEngage");
    const engageOverlay = $("#engageOverlay");
    const frameOverlay = $("#frameOverlay");

    if (videoEngage && engageOverlay) {
        const w = videoEngage.videoWidth || state.frame.w;
        const h = videoEngage.videoHeight || state.frame.h;
        engageOverlay.width = w;
        engageOverlay.height = h;
    }

    if (frameOverlay) {
        frameOverlay.width = state.frame.w;
        frameOverlay.height = state.frame.h;
    }
};

// Depth video handling
APP.core.video.fetchDepthVideo = async function () {
    const { state } = APP.core;
    const { log } = APP.ui.logging;

    // Depth is optional - skip silently if no URL
    if (!state.hf.depthVideoUrl) {
        return;
    }

    try {
        const resp = await fetch(state.hf.depthVideoUrl, { cache: "no-store" });

        if (!resp.ok) {
            // 404 = depth not enabled/available - this is fine, not an error
            if (resp.status === 404) {
                state.hf.depthVideoUrl = null;
                return;
            }
            // 202 = still processing
            if (resp.status === 202) {
                return;
            }
            throw new Error(`Failed to fetch depth video: ${resp.statusText}`);
        }

        const nullOrigin = (window.location && window.location.origin) === "null" || (window.location && window.location.protocol === "file:");
        if (nullOrigin) {
            state.hf.depthBlob = null;
            state.hf.depthVideoUrl = `${state.hf.depthVideoUrl}?t=${Date.now()}`;
            log("Depth video ready (streaming URL)");
            return;
        }

        const blob = await resp.blob();
        state.hf.depthBlob = blob;
        const blobUrl = URL.createObjectURL(blob);
        state.hf.depthVideoUrl = blobUrl;

        log(`Depth video ready (${(blob.size / 1024 / 1024).toFixed(1)} MB)`, "g");
        APP.core.video.updateDepthChip();
    } catch (err) {
        // Don't log as error - depth is optional
        state.hf.depthVideoUrl = null;
        state.hf.depthBlob = null;
    }
};

APP.core.video.fetchDepthFirstFrame = async function () {
    const { state } = APP.core;
    const { log } = APP.ui.logging;

    // Depth is optional - skip silently if no URL
    if (!state.hf.depthFirstFrameUrl) return;

    try {
        const resp = await fetch(state.hf.depthFirstFrameUrl, { cache: "no-store" });

        // 404 or other errors - depth not available, that's fine
        if (!resp.ok) {
            state.hf.depthFirstFrameUrl = null;
            return;
        }

        const blob = await resp.blob();
        state.hf.depthFirstFrameBlob = blob;
        state.hf.depthFirstFrameUrl = URL.createObjectURL(blob);
        log("First frame depth ready", "g");
    } catch (err) {
        // Silently clear - depth is optional
        state.hf.depthFirstFrameUrl = null;
        state.hf.depthFirstFrameBlob = null;
    }
};

APP.core.video.fetchProcessedVideo = async function () {
    const { state } = APP.core;
    const { log } = APP.ui.logging;
    const { $ } = APP.core.utils;

    const resp = await fetch(state.hf.videoUrl, { cache: "no-store" });

    if (!resp.ok) {
        if (resp.status === 202) {
            const err = new Error("Video still processing");
            err.code = "VIDEO_PENDING";
            throw err;
        }
        throw new Error(`Failed to fetch video: ${resp.statusText}`);
    }

    const nullOrigin = (window.location && window.location.origin) === "null" || (window.location && window.location.protocol === "file:");
    if (nullOrigin) {
        state.hf.processedBlob = null;
        state.hf.processedUrl = `${state.hf.videoUrl}?t=${Date.now()}`;
        const btnEngage = $("#btnEngage");
        if (btnEngage) btnEngage.disabled = false;
        log("Processed video ready (streaming URL)");
        return;
    }

    const blob = await resp.blob();

    if (state.hf.processedUrl && state.hf.processedUrl.startsWith("blob:")) {
        URL.revokeObjectURL(state.hf.processedUrl);
    }

    state.hf.processedBlob = blob;
    state.hf.processedUrl = URL.createObjectURL(blob);

    const btnEngage = $("#btnEngage");
    if (btnEngage) btnEngage.disabled = false;
    log(`Processed video ready (${(blob.size / 1024 / 1024).toFixed(1)} MB)`);
};

APP.core.video.updateDepthChip = function () {
    const { state } = APP.core;
    const { $ } = APP.core.utils;

    const chipDepth = $("#chipDepth");
    if (!chipDepth) return;

    if (state.hf.depthVideoUrl || state.hf.depthBlob) {
        chipDepth.style.cursor = "pointer";
        chipDepth.style.opacity = "1";
    } else {
        chipDepth.style.cursor = "not-allowed";
        chipDepth.style.opacity = "0.5";
    }
};

APP.core.video.toggleDepthView = function () {
    const { state } = APP.core;
    const { $, log } = APP.core.utils;
    const { log: uiLog } = APP.ui.logging;

    if (!state.hf.depthVideoUrl && !state.hf.depthBlob) {
        uiLog("Depth video not available yet. Run Reason and wait for processing.", "w");
        return;
    }

    state.useDepthFeed = !state.useDepthFeed;

    const videoEngage = $("#videoEngage");
    const chipDepth = $("#chipDepth");

    if (state.useDepthFeed) {
        if (chipDepth) chipDepth.textContent = "VIEW:DEPTH";
        if (videoEngage) {
            const currentTime = videoEngage.currentTime;
            const wasPlaying = !videoEngage.paused;
            videoEngage.src = state.hf.depthVideoUrl;
            videoEngage.load();
            videoEngage.currentTime = currentTime;
            if (wasPlaying) videoEngage.play();
        }
    } else {
        if (chipDepth) chipDepth.textContent = "VIEW:DEFAULT";
        if (videoEngage) {
            const currentTime = videoEngage.currentTime;
            const wasPlaying = !videoEngage.paused;
            const feedUrl = state.useProcessedFeed ? state.hf.processedUrl : state.videoUrl;
            videoEngage.src = feedUrl;
            videoEngage.load();
            videoEngage.currentTime = currentTime;
            if (wasPlaying) videoEngage.play();
        }
    }
};

APP.core.video.toggleFirstFrameDepthView = function () {
    const { state } = APP.core;
    const { $ } = APP.core.utils;
    const { log } = APP.ui.logging;

    if (!state.hf.depthFirstFrameUrl) {
        log("First frame depth not available", "w");
        return;
    }

    state.useFrameDepthView = !state.useFrameDepthView;

    const frameCanvas = $("#frameCanvas");
    const chipFrameDepth = $("#chipFrameDepth");

    if (state.useFrameDepthView) {
        if (chipFrameDepth) chipFrameDepth.textContent = "VIEW:DEPTH";
        // Draw depth first frame
        const img = new Image();
        img.onload = () => {
            if (frameCanvas) {
                frameCanvas.width = state.frame.w;
                frameCanvas.height = state.frame.h;
                frameCanvas.getContext("2d").drawImage(img, 0, 0, state.frame.w, state.frame.h);
                APP.ui.overlays.renderFrameOverlay();
            }
        };
        img.src = state.hf.depthFirstFrameUrl;
    } else {
        if (chipFrameDepth) chipFrameDepth.textContent = "VIEW:DEFAULT";
        // Re-draw original first frame
        APP.core.video.drawFirstFrame();
        APP.ui.overlays.renderFrameOverlay();
    }
};

APP.core.video.toggleProcessedFeed = function () {
    const { state } = APP.core;
    const { $ } = APP.core.utils;
    const { log } = APP.ui.logging;

    if (!state.hf.processedUrl) {
        log("Processed video not available yet", "w");
        return;
    }

    state.useProcessedFeed = !state.useProcessedFeed;
    state.useDepthFeed = false; // Reset depth view when switching feeds

    const videoEngage = $("#videoEngage");
    const chipFeed = $("#chipFeed");
    const chipDepth = $("#chipDepth");

    if (state.useProcessedFeed) {
        if (chipFeed) chipFeed.textContent = "FEED:HF";
        if (videoEngage) {
            const currentTime = videoEngage.currentTime;
            const wasPlaying = !videoEngage.paused;
            videoEngage.src = state.hf.processedUrl;
            videoEngage.load();
            videoEngage.currentTime = currentTime;
            if (wasPlaying) videoEngage.play();
        }
    } else {
        if (chipFeed) chipFeed.textContent = "FEED:RAW";
        if (videoEngage) {
            const currentTime = videoEngage.currentTime;
            const wasPlaying = !videoEngage.paused;
            videoEngage.src = state.videoUrl;
            videoEngage.load();
            videoEngage.currentTime = currentTime;
            if (wasPlaying) videoEngage.play();
        }
    }

    if (chipDepth) chipDepth.textContent = "VIEW:DEFAULT";
};

// ========= Streaming Mode for Tab 2 (Live Backend Processing) =========

APP.core.video.setStreamingMode = function (url) {
    const { $ } = APP.core.utils;
    const videoEngage = $("#videoEngage");
    const engageEmpty = $("#engageEmpty");

    // Ensure stream image element exists
    let streamView = $("#streamView");
    if (!streamView) {
        streamView = document.createElement("img");
        streamView.id = "streamView";
        streamView.style.width = "100%";
        streamView.style.height = "100%";
        streamView.style.objectFit = "contain";
        streamView.style.position = "absolute";
        streamView.style.top = "0";
        streamView.style.left = "0";
        streamView.style.zIndex = "10"; // Above video
        streamView.style.backgroundColor = "#000";

        // Insert into the wrapper (parent of videoEngage)
        if (videoEngage && videoEngage.parentNode) {
            videoEngage.parentNode.appendChild(streamView);
            // Ensure container is relative for absolute positioning
            if (getComputedStyle(videoEngage.parentNode).position === "static") {
                videoEngage.parentNode.style.position = "relative";
            }
        }
    }

    if (streamView) {
        // Reset state
        streamView.style.display = "block";
        streamView.onerror = () => {
            // If stream fails (404 etc), silently revert
            streamView.style.display = "none";
            if (videoEngage) videoEngage.style.display = "block";
            if (engageEmpty && !videoEngage.src) engageEmpty.style.display = "flex";
        };
        streamView.src = url;

        if (videoEngage) videoEngage.style.display = "none";

        // Also hide empty state
        if (engageEmpty) engageEmpty.style.display = "none";
    }
};

APP.core.video.stopStreamingMode = function () {
    const { $ } = APP.core.utils;
    const videoEngage = $("#videoEngage");

    const streamView = $("#streamView");
    if (streamView) {
        streamView.src = ""; // Stop connection
        streamView.style.display = "none";
    }
    if (videoEngage) videoEngage.style.display = "block";
};

// ========= Display Processed First Frame (from backend) =========

APP.core.video.displayProcessedFirstFrame = function () {
    const { state } = APP.core;
    const { $ } = APP.core.utils;
    const { log } = APP.ui.logging;

    const frameCanvas = $("#frameCanvas");
    const frameOverlay = $("#frameOverlay");
    const frameEmpty = $("#frameEmpty");
    const frameNote = $("#frameNote");

    if (!state.hf.firstFrameUrl) {
        log("Processed first frame URL not available", "w");
        return;
    }

    const img = new Image();
    img.crossOrigin = "anonymous";
    img.onload = () => {
        if (frameCanvas) {
            // Update frame dimensions from image
            state.frame.w = img.naturalWidth || 1280;
            state.frame.h = img.naturalHeight || 720;

            // Resize both canvas and overlay to match frame dimensions
            frameCanvas.width = state.frame.w;
            frameCanvas.height = state.frame.h;
            frameCanvas.getContext("2d").drawImage(img, 0, 0, state.frame.w, state.frame.h);

            // CRITICAL: Resize frameOverlay to match so bbox coordinates align
            if (frameOverlay) {
                frameOverlay.width = state.frame.w;
                frameOverlay.height = state.frame.h;
            }

            // Hide empty state
            if (frameEmpty) frameEmpty.style.display = "none";
            if (frameNote) frameNote.textContent = "Processed (from backend)";

            // Re-render overlay on top (now with matching dimensions)
            if (APP.ui.overlays.renderFrameOverlay) {
                APP.ui.overlays.renderFrameOverlay();
            }

            log("Processed first frame displayed", "g");
        }
    };
    img.onerror = () => {
        log("Failed to load processed first frame", "e");
        // Fallback to local first frame
        APP.core.video.drawFirstFrame();
    };
    img.src = state.hf.firstFrameUrl;
};

// ========= Display First Frame with Depth Overlay (if available) =========

APP.core.video.displayFirstFrameWithDepth = function () {
    const { state } = APP.core;
    const { $ } = APP.core.utils;

    // Check if we're in depth view mode and depth is available
    if (state.useFrameDepthView && state.hf.depthFirstFrameUrl) {
        const frameCanvas = $("#frameCanvas");
        const img = new Image();
        img.crossOrigin = "anonymous";
        img.onload = () => {
            if (frameCanvas) {
                frameCanvas.width = state.frame.w;
                frameCanvas.height = state.frame.h;
                frameCanvas.getContext("2d").drawImage(img, 0, 0, state.frame.w, state.frame.h);
                if (APP.ui.overlays.renderFrameOverlay) {
                    APP.ui.overlays.renderFrameOverlay();
                }
            }
        };
        img.onerror = () => {
            // Fallback to processed or raw first frame
            APP.core.video.displayProcessedFirstFrame();
        };
        img.src = state.hf.depthFirstFrameUrl;
    } else if (state.hf.firstFrameUrl) {
        // Show processed first frame
        APP.core.video.displayProcessedFirstFrame();
    } else {
        // Fallback to local video first frame
        APP.core.video.drawFirstFrame();
    }
};