// realistic_system.js - Global Realistic Lighting, Shadows, and Water Effects for ALL elements (including addons)
// Features:
// - Dynamic colored light propagation from fire, lights, hot pixels, etc.
// - Realistic occlusion shadows (darker in crevices/caves), modulated by light intensity
// - Wavy foam on ALL liquids (water, oils, mod liquids)
// - Works with any mods/addons automatically (liquids get waves, all get lit/shadowed)
// Performance: Low-res lightmap + cached shadows = smooth even on large views
// Install: Save as realistic_system.js in mods folder, load via Mod Manager

// === LIGHTMAP SYSTEM (Dynamic Glow/Light Propagation) ===
var lightmap = [];
var nextLightmap = [];
var lightmapScale = 4; // Higher = lower quality/faster (2-8 recommended)
var lightSourceBoost = 3;
var falloff = 0.85;

// Helper functions
function rgbToArray(colorString) {
  if (typeof colorString !== "string") return [255,255,255];
  if (colorString.startsWith("rgb")) {
    return colorString.slice(4, -1).split(",").map(val => parseInt(val.trim()));
  } else if (colorString.startsWith("#")) {
    let hex = colorString.slice(1);
    if (hex.length === 3) hex = hex.split("").map(char => char + char).join("");
    let r = parseInt(hex.slice(0, 2), 16);
    let g = parseInt(hex.slice(2, 4), 16);
    let b = parseInt(hex.slice(4, 6), 16);
    return [r, g, b];
  }
  return [255,255,255];
}

function scaleList(numbers, scale) {
  return numbers.map(number => number * scale);
}

function rgbToHsv(r, g, b) {
  r /= 255; g /= 255; b /= 255;
  let max = Math.max(r, g, b), min = Math.min(r, g, b);
  let h, s, v = max;
  let d = max - min;
  s = max === 0 ? 0 : d / max;
  if (max === min) h = 0;
  else {
    switch (max) {
      case r: h = (g - b) / d + (g < b ? 6 : 0); break;
      case g: h = (b - r) / d + 2; break;
      case b: h = (r - g) / d + 4; break;
    }
    h /= 6;
  }
  return [h, s, v];
}

function hsvToRgb(h, s, v) {
  let i = Math.floor(h * 6);
  let f = h * 6 - i;
  let p = v * (1 - s);
  let q = v * (1 - f * s);
  let t = v * (1 - (1 - f) * s);
  let r, g, b;
  switch (i % 6) {
    case 0: r = v; g = t; b = p; break;
    case 1: r = q; g = v; b = p; break;
    case 2: r = p; g = v; b = t; break;
    case 3: r = p; g = q; b = v; break;
    case 4: r = t; g = p; b = v; break;
    case 5: r = v; g = p; b = q; break;
  }
  return [Math.round(r * 255), Math.round(g * 255), Math.round(b * 255)];
}

function initializeLightmap(w, h) {
  let lw = Math.ceil(w / lightmapScale) + 1;
  let lh = Math.ceil(h / lightmapScale) + 1;
  function createArray(width_, height_) {
    return Array.from({length: height_}, () => Array.from({length: width_}, () => ({color: [0, 0, 0]})));
  }
  lightmap = createArray(lw, lh);
  nextLightmap = createArray(lw, lh);
}

function propagateLightmap() {
  if (!lightmap[0]) return;
  let width = lightmap[0].length;
  let height = lightmap.length;
  let neighbors = [{dx:1,dy:0},{dx:-1,dy:0},{dx:0,dy:1},{dx:0,dy:-1}];
  for (let y = 0; y < height; y++) {
    for (let x = 0; x < width; x++) {
      let totalColor = [0,0,0];
      let neighborCount = 0;
      neighbors.forEach(n => {
        let nx = x + n.dx, ny = y + n.dy;
        if (nx >= 0 && ny >= 0 && nx < width && ny < height) {
          totalColor[0] += lightmap[ny][nx].color[0];
          totalColor[1] += lightmap[ny][nx].color[1];
          totalColor[2] += lightmap[ny][nx].color[2];
          neighborCount++;
        }
      });
      nextLightmap[y][x] = {
        color: [
          Math.min(765, Math.max(0, (totalColor[0] / neighborCount) * falloff)),
          Math.min(765, Math.max(0, (totalColor[1] / neighborCount) * falloff)),
          Math.min(765, Math.max(0, (totalColor[2] / neighborCount) * falloff))
        ]
      };
    }
  }
  // Copy next to current
  for (let y = 0; y < height; y++) {
    for (let x = 0; x < width; x++) {
      lightmap[y][x] = {...nextLightmap[y][x]};
    }
  }
}

function renderLightmap(ctx) {
  if (!lightmap[0]) return;
  let lw = lightmap[0].length;
  let lh = lightmap.length;
  for (let y = 0; y < lh; y++) {
    for (let x = 0; x < lw; x++) {
      let color = lightmap[y][x].color;
      let r = color[0], g = color[1], b = color[2];
      if (r > 16 || g > 16 || b > 16) {
        let hsv = rgbToHsv(r, g, b);
        let newColor = hsvToRgb(hsv[0], hsv[1], 1);
        let alpha = hsv[2];
        ctx.globalAlpha = 1;
        ctx.fillStyle = `rgba(${newColor[0]},${newColor[1]},${newColor[2]},${alpha * 0.4})`;
        ctx.fillRect(x * pixelSize * lightmapScale, y * pixelSize * lightmapScale, pixelSize * lightmapScale, pixelSize * lightmapScale);
        ctx.fillStyle = `rgba(${newColor[0]},${newColor[1]},${newColor[2]},${alpha * 0.25})`;
        ctx.fillRect((x * pixelSize - pixelSizeHalf) * lightmapScale, (y * pixelSize - pixelSizeHalf) * lightmapScale,
                     pixelSize * lightmapScale * 2, pixelSize * lightmapScale * 2);
      }
    }
  }
}

function glowItsOwnColor(pixel) {
  if (!pixel.color) return;
  let x = Math.floor(pixel.x / lightmapScale);
  let y = Math.floor(pixel.y / lightmapScale);
  if (x < 0 || y < 0 || x >= lightmap[0]?.length || y >= lightmap?.length) return;
  lightmap[y][x].color = scaleList(rgbToArray(pixel.color), lightSourceBoost);
}

function glowPowered(pixel) {
  if (!pixel.charge || pixel.charge <= 0 || !pixel.color) return;
  glowItsOwnColor(pixel);
}

// Override ticks for common light sources (works with addons if they use these elements)
let lightEmitters = [
  "fire", "cold_fire", "plasma", "lava", "magma", "sun", "light", "liquid_light", "laser", "flash", "rainbow",
  "ember", "fw_ember", "explosion", "n_explosion", "supernova", "fireball", "blaster", "lightning", "electric",
  "positron", "neutron", "proton", "radiation", "fallout", "rad_cloud", "rad_steam", "uranium", "molten_uranium"
];
lightEmitters.forEach(elName => {
  let el = elements[elName];
  if (el && el.tick) {
    let origTick = el.tick;
    el.tick = function(pixel) {
      origTick(pixel);
      glowItsOwnColor(pixel);
    };
  }
});
["neon", "led", "light_bulb"].forEach(elName => {
  let el = elements[elName];
  if (el && el.tick) {
    let origTick = el.tick;
    el.tick = function(pixel) {
      origTick(pixel);
      glowPowered(pixel);
    };
  }
});

// Temp-based glow for hot pixels (metals, etc.)
function glowTemp(pixel) {
  let t = pixel.temp;
  if (t < 500) return;
  let intensity = Math.min(1, (t - 500) / 2000);
  let r = Math.min(255, 100 + 155 * intensity);
  let g = Math.min(255, 50 * intensity);
  let b = Math.min(255, 10 * intensity);
  let x = Math.floor(pixel.x / lightmapScale);
  let y = Math.floor(pixel.y / lightmapScale);
  if (x < 0 || y < 0 || x >= lightmap[0]?.length || y >= lightmap?.length) return;
  lightmap[y][x].color = scaleList([r, g, b], lightSourceBoost * intensity);
}
runPerPixel(glowTemp);

// Lightmap render hook
renderPrePixel(function(ctx) {
  if (!paused) propagateLightmap();
  renderLightmap(ctx);
});

// Init lightmap
if (typeof runAfterReset !== 'undefined') {
  runAfterReset(() => initializeLightmap(width, height));
} else {
  setTimeout(() => initializeLightmap(width, height), 100);
}

// === SHADOWS / OCCLUSION (Realistic Darkness in Shadows) ===
const DEFAULT_LIGHT_FACTOR = 0.8;
const MIN_LIGHT_INTENSITY = 0.4;
const MAX_DIRECT_NEIGHBORS = 4;
const FOLLOWUP_COORDS_TO_CHECK = [
  [-1,-1],[-1,1],[1,-1],[1,1], [-2,0],[2,0],[0,-2],[0,2],
  [-3,0],[3,0],[0,-3],[0,3], [-4,0],[4,0],[0,-4],[0,4]
];
let transparentElements = [];
function initTransparent() {
  transparentElements = [];
  Object.keys(elements).forEach(name => {
    let el = elements[name];
    if (el.state === "gas" || el.category === "special" || el.putInTransparentList) {
      transparentElements.push(name);
    }
  });
  // Add common transparents
  ["glass","stained_glass","glass_shard","ice","led"].forEach(t => transparentElements.includes(t) || transparentElements.push(t));
}
initTransparent();

let frameCounter = 0;
let pixelBrightnessCache = {};

function isOutOfBounds(x, y) {
  return x >= width || y >= height || x < 0 || y < 0;
}

function getOutOfBoundsNeighbors(pixel) {
  let out = [];
  [[-1,0],[1,0],[0,-1],[0,1]].forEach(([dx,dy]) => {
    let nx = pixel.x + dx, ny = pixel.y + dy;
    if (isOutOfBounds(nx, ny)) out.push({x:nx,y:ny});
  });
  return out;
}

function calculateBrightness(pixel) {
  let neighCount = getNeighbors(pixel).length + getOutOfBoundsNeighbors(pixel).length;
  if (neighCount >= MAX_DIRECT_NEIGHBORS) {
    let lightFactor = computeBrightnessFurther(pixel);
    return adjustBrightness(lightFactor);
  }
  return 1;
}

function computeBrightnessFurther(pixel) {
  let blockers = 0;
  FOLLOWUP_COORDS_TO_CHECK.forEach(([dx,dy]) => {
    let nx = pixel.x + dx, ny = pixel.y + dy;
    if (isOutOfBounds(nx, ny)) {
      blockers++;
      return;
    }
    let elName = pixelMap[nx]?.[ny]?.element;
    if (elName && !transparentElements.includes(elName)) blockers++;
  });
  return 1 - (blockers / FOLLOWUP_COORDS_TO_CHECK.length);
}

function adjustBrightness(factor) {
  return factor * DEFAULT_LIGHT_FACTOR + MIN_LIGHT_INTENSITY;
}

function applyShadows(ctx) {
  if (frameCounter % 2 === 0) {
    currentPixels.forEach(pixel => {
      let brightness = calculateBrightness(pixel);
      pixelBrightnessCache[`${pixel.x},${pixel.y}`] = brightness;
    });
  }
  currentPixels.forEach(pixel => {
    let brightness = pixelBrightnessCache[`${pixel.x},${pixel.y}`] || 1;
    // Sample local lightmap intensity
    let lx = Math.floor(pixel.x / lightmapScale);
    let ly = Math.floor(pixel.y / lightmapScale);
    let lightInt = 0;
    if (ly >= 0 && ly < lightmap?.length && lx >= 0 && lx < lightmap[0]?.length) {
      let lm = lightmap[ly][lx].color;
      lightInt = (lm[0] + lm[1] + lm[2]) / (255 * 3);
    }
    let shadeAlpha = (1 - brightness) * 0.7 * Math.max(0.2, 1 - lightInt * 0.8);
    ctx.globalAlpha = shadeAlpha;
    ctx.fillStyle = "#000";
    ctx.fillRect(pixel.x * pixelSize, pixel.y * pixelSize, pixelSize, pixelSize);
  });
  frameCounter++;
}

renderPostPixel(applyShadows);

// === REALISTIC WATER / LIQUIDS (Waves & Foam on ALL Liquids) ===
renderEachPixel(function(pixel, ctx) {
  let el = elements[pixel.element];
  if (el && el.state === "liquid") {
    // Wavy foam surface
    let time = (pixelTicks * 0.01 + pixel.x * 0.15 + pixel.y * 0.03) % (Math.PI * 2);
    let waveOffset = Math.sin(time) * 0.35 - 0.15;
    let foamY = Math.floor(pixel.y + waveOffset);
    let foamAlpha = 0.6 + Math.sin(time * 1.5) * 0.3;
    let foamColor = "#e8f4ff"; // Light blue-white foam
    drawSquare(ctx, foamColor, pixel.x, foamY, 1, foamAlpha * 0.4);
    // Subtle caustic glow if lit (bonus realism)
    let lx = Math.floor(pixel.x / lightmapScale);
    let ly = Math.floor(pixel.y / lightmapScale);
    if (ly >= 0 && ly < lightmap?.length && lx >= 0 && lx < lightmap[0]?.length) {
      let lmBright = (lightmap[ly][lx].color[0] + lightmap[ly][lx].color[1] + lightmap[ly][lx].color[2]) / (255 * 3);
      if (lmBright > 0.2) {
        let causticAlpha = lmBright * 0.3;
        let causticX = pixel.x + Math.sin(time * 0.7) * 0.2;
        let causticY = pixel.y + 0.5 + Math.cos(time * 1.2) * 0.15;
        drawSquare(ctx, "#00ff88", causticX, causticY, 0.8, causticAlpha);
      }
    }
  }
});

// Re-init transparent on element changes (for mods)
if (typeof runEveryTick !== 'undefined') {
  runEveryTick(initTransparent);
}