import { announce, apiJson, createLocalState, setActiveButton } from "./core.js";
import {
  clamp,
  hexToRgb,
  hsvToRgb,
  normalizeHex,
  rgbToHex,
  rgbToHsv,
  updateRecentColors,
} from "./color-math.js";
import { setControlBusy, setControlReady } from "./interaction-feedback.js";

const localState = createLocalState("colors", 1);
const savedState = localState.load({});
let recentColors = Array.isArray(savedState.recentColors)
  ? savedState.recentColors.map(normalizeHex).filter(Boolean).slice(0, 10)
  : [];
let mode = savedState.mode === "rgb" ? "rgb" : "hsv";
let palette = [];
let activeTrigger = null;
let originalColor = "#000000";
let currentRgb = hexToRgb(originalColor);
let currentHsv = rgbToHsv(currentRgb);
let paletteEditing = false;
let pickerReadonly = false;

const overlay = document.createElement("div");
overlay.id = "color-picker-overlay";
overlay.className = "color-picker-overlay";
overlay.hidden = true;
overlay.innerHTML = `
  <section class="color-picker-panel" role="dialog" aria-modal="true" aria-labelledby="color-picker-title">
    <header class="color-picker-header">
      <div><p class="eyebrow">软件自有控件</p><h2 id="color-picker-title">选择颜色</h2></div>
      <button class="compact-button" type="button" data-color-action="cancel" aria-label="关闭颜色选择器">关闭</button>
    </header>
    <div class="color-comparison" aria-label="原颜色与新颜色对比">
      <div><span>原颜色</span><i id="color-original-preview"></i></div>
      <div><span>新颜色</span><i id="color-current-preview"></i></div>
    </div>
    <div class="color-mode-tabs segmented" role="tablist" aria-label="颜色模式">
      <button type="button" role="tab" data-color-mode="hsv">HSV</button>
      <button type="button" role="tab" data-color-mode="rgb">RGB</button>
    </div>
    <div id="color-hsv-panel" class="color-mode-panel" role="tabpanel">
      <div id="color-sv-field" class="color-sv-field" role="slider" tabindex="0" aria-label="饱和度和明度" aria-valuemin="0" aria-valuemax="100">
        <span id="color-sv-handle" class="color-track-handle"></span>
      </div>
      <div id="color-hue-track" class="color-linear-track color-hue-track" role="slider" tabindex="0" aria-label="色相" aria-valuemin="0" aria-valuemax="360">
        <span id="color-hue-handle" class="color-track-handle"></span>
      </div>
      <div class="color-number-grid">
        <label>H<input id="color-h" type="number" min="0" max="360" inputmode="numeric"></label>
        <label>S<input id="color-s" type="number" min="0" max="100" inputmode="numeric"></label>
        <label>V<input id="color-v" type="number" min="0" max="100" inputmode="numeric"></label>
      </div>
    </div>
    <div id="color-rgb-panel" class="color-mode-panel" role="tabpanel" hidden>
      <div class="rgb-channel"><span>R</span><div class="color-linear-track" data-rgb-track="r" role="slider" tabindex="0" aria-label="红色通道" aria-valuemin="0" aria-valuemax="255"><span class="color-track-handle"></span></div><input id="color-r" type="number" min="0" max="255" inputmode="numeric"></div>
      <div class="rgb-channel"><span>G</span><div class="color-linear-track" data-rgb-track="g" role="slider" tabindex="0" aria-label="绿色通道" aria-valuemin="0" aria-valuemax="255"><span class="color-track-handle"></span></div><input id="color-g" type="number" min="0" max="255" inputmode="numeric"></div>
      <div class="rgb-channel"><span>B</span><div class="color-linear-track" data-rgb-track="b" role="slider" tabindex="0" aria-label="蓝色通道" aria-valuemin="0" aria-valuemax="255"><span class="color-track-handle"></span></div><input id="color-b" type="number" min="0" max="255" inputmode="numeric"></div>
    </div>
    <label class="color-hex-field">HEX<input id="color-hex" type="text" maxlength="7" autocapitalize="characters" spellcheck="false" inputmode="text"></label>
    <section class="color-collection" aria-labelledby="recent-colors-title">
      <div class="color-collection-heading"><h3 id="recent-colors-title">最近颜色</h3></div>
      <div id="recent-colors" class="color-swatch-grid"></div>
    </section>
    <section class="color-collection" aria-labelledby="palette-colors-title">
      <div class="color-collection-heading"><h3 id="palette-colors-title">设备收藏色</h3><div><button type="button" class="compact-button" data-color-action="favorite">收藏当前</button><button type="button" class="compact-button" data-color-action="edit-palette">编辑</button></div></div>
      <div id="palette-colors" class="color-swatch-grid"></div>
      <p id="palette-status" class="hint" aria-live="polite"></p>
    </section>
    <footer class="color-picker-actions">
      <button type="button" data-color-action="cancel">取消</button>
      <button type="button" class="primary-button" data-color-action="confirm">使用此颜色</button>
    </footer>
  </section>`;
document.body.appendChild(overlay);

const panel = overlay.querySelector(".color-picker-panel");
const hsvPanel = document.getElementById("color-hsv-panel");
const rgbPanel = document.getElementById("color-rgb-panel");
const svField = document.getElementById("color-sv-field");
const hueTrack = document.getElementById("color-hue-track");
const modeButtons = Array.from(overlay.querySelectorAll("[data-color-mode]"));
const rgbTracks = Array.from(overlay.querySelectorAll("[data-rgb-track]"));

function persistLocalColors() {
  localState.save({ recentColors, mode });
}

function renderTrigger(trigger) {
  const value = normalizeHex(trigger.value) || "#000000";
  trigger.value = value;
  trigger.querySelector(".color-trigger-swatch").style.background = value;
  trigger.querySelector(".color-trigger-value").textContent = value;
}

function setMode(nextMode) {
  mode = nextMode === "rgb" ? "rgb" : "hsv";
  setActiveButton(modeButtons, modeButtons.find((button) => button.dataset.colorMode === mode));
  modeButtons.forEach((button) => button.setAttribute("aria-selected", String(button.dataset.colorMode === mode)));
  hsvPanel.hidden = mode !== "hsv";
  rgbPanel.hidden = mode !== "rgb";
  persistLocalColors();
}

function setCurrentRgb(rgb) {
  if (pickerReadonly) return;
  currentRgb = {
    r: Math.round(clamp(rgb.r, 0, 255)),
    g: Math.round(clamp(rgb.g, 0, 255)),
    b: Math.round(clamp(rgb.b, 0, 255)),
  };
  currentHsv = rgbToHsv(currentRgb);
  renderPicker();
}

function setCurrentHsv(hsv) {
  if (pickerReadonly) return;
  currentHsv = {
    h: Math.round(clamp(hsv.h, 0, 360)),
    s: Math.round(clamp(hsv.s, 0, 100)),
    v: Math.round(clamp(hsv.v, 0, 100)),
  };
  currentRgb = hsvToRgb(currentHsv);
  renderPicker();
}

function renderPicker() {
  const hex = rgbToHex(currentRgb);
  document.getElementById("color-original-preview").style.background = originalColor;
  document.getElementById("color-current-preview").style.background = hex;
  document.getElementById("color-hex").value = hex;
  for (const channel of ["r", "g", "b"]) document.getElementById(`color-${channel}`).value = currentRgb[channel];
  for (const channel of ["h", "s", "v"]) document.getElementById(`color-${channel}`).value = currentHsv[channel];

  svField.style.background = `linear-gradient(to top, #000, transparent), linear-gradient(to right, #fff, hsl(${currentHsv.h} 100% 50%))`;
  const svHandle = document.getElementById("color-sv-handle");
  svHandle.style.left = `${currentHsv.s}%`;
  svHandle.style.top = `${100 - currentHsv.v}%`;
  svField.setAttribute("aria-valuenow", String(currentHsv.s));
  svField.setAttribute("aria-valuetext", `饱和度 ${currentHsv.s}%，明度 ${currentHsv.v}%`);
  document.getElementById("color-hue-handle").style.left = `${currentHsv.h / 3.6}%`;
  hueTrack.setAttribute("aria-valuenow", String(currentHsv.h));

  rgbTracks.forEach((track) => {
    const channel = track.dataset.rgbTrack;
    const start = { ...currentRgb, [channel]: 0 };
    const end = { ...currentRgb, [channel]: 255 };
    track.style.background = `linear-gradient(to right, ${rgbToHex(start)}, ${rgbToHex(end)})`;
    track.querySelector(".color-track-handle").style.left = `${(currentRgb[channel] / 255) * 100}%`;
    track.setAttribute("aria-valuenow", String(currentRgb[channel]));
  });
  renderSwatches();
}

function swatchButton(color, label) {
  const button = document.createElement("button");
  button.type = "button";
  button.className = "color-swatch";
  button.style.background = color;
  button.title = color;
  button.setAttribute("aria-label", `${label} ${color}`);
  button.addEventListener("click", () => setCurrentRgb(hexToRgb(color)));
  return button;
}

function renderSwatches() {
  const recentContainer = document.getElementById("recent-colors");
  recentContainer.replaceChildren(...recentColors.map((color) => swatchButton(color, "最近颜色")));
  if (!recentColors.length) recentContainer.textContent = "还没有最近颜色";

  const paletteContainer = document.getElementById("palette-colors");
  paletteContainer.replaceChildren(...palette.map((color) => {
    const wrapper = document.createElement("span");
    wrapper.className = "palette-swatch";
    wrapper.appendChild(swatchButton(color, "收藏颜色"));
    if (paletteEditing) {
      const remove = document.createElement("button");
      remove.type = "button";
      remove.className = "palette-remove";
      remove.textContent = "×";
      remove.setAttribute("aria-label", `删除收藏颜色 ${color}`);
      remove.addEventListener("click", () => deleteFavorite(color, remove));
      wrapper.appendChild(remove);
    }
    return wrapper;
  }));
  if (!palette.length) paletteContainer.textContent = "收藏色板为空";
}

async function loadPalette() {
  const status = document.getElementById("palette-status");
  status.textContent = "正在读取设备收藏色…";
  try {
    const response = await apiJson("/api/colors/palette");
    palette = response.colors.map(normalizeHex).filter(Boolean);
    status.textContent = `${palette.length} / ${response.limit}`;
    renderSwatches();
  } catch (error) {
    status.textContent = `收藏色读取失败：${error.message}`;
  }
}

async function addFavorite(control) {
  setControlBusy(control, { label: "正在收藏…", message: "正在收藏当前颜色…" });
  try {
    const response = await apiJson("/api/colors/palette", {
      method: "POST",
      body: JSON.stringify({ color: rgbToHex(currentRgb) }),
    });
    palette = response.colors;
    document.getElementById("palette-status").textContent = `${palette.length} / ${response.limit}`;
    renderSwatches();
  } catch (error) {
    announce(`收藏颜色失败：${error.message}`, true);
  } finally {
    setControlReady(control);
  }
}

async function deleteFavorite(color, control) {
  setControlBusy(control, { message: `正在删除收藏颜色 ${color}…` });
  try {
    const response = await apiJson(`/api/colors/palette/${color.slice(1)}`, { method: "DELETE" });
    palette = response.colors;
    document.getElementById("palette-status").textContent = `${palette.length} / ${response.limit}`;
    renderSwatches();
  } catch (error) {
    announce(`删除收藏颜色失败：${error.message}`, true);
  } finally {
    setControlReady(control);
  }
}

function trackRatio(event, track) {
  const rect = track.getBoundingClientRect();
  return clamp((event.clientX - rect.left) / rect.width, 0, 1);
}

function bindHorizontalTrack(track, update) {
  let activePointer = null;
  const move = (event) => {
    if (activePointer !== event.pointerId) return;
    update(trackRatio(event, track));
  };
  track.addEventListener("pointerdown", (event) => {
    activePointer = event.pointerId;
    track.setPointerCapture(event.pointerId);
    update(trackRatio(event, track));
  });
  track.addEventListener("pointermove", move);
  const finish = (event) => { if (activePointer === event.pointerId) activePointer = null; };
  track.addEventListener("pointerup", finish);
  track.addEventListener("pointercancel", finish);
}

bindHorizontalTrack(hueTrack, (ratio) => setCurrentHsv({ ...currentHsv, h: ratio * 360 }));
rgbTracks.forEach((track) => bindHorizontalTrack(track, (ratio) => {
  setCurrentRgb({ ...currentRgb, [track.dataset.rgbTrack]: ratio * 255 });
}));

let svPointer = null;
function updateSvFromPointer(event) {
  if (event.pointerId !== svPointer) return;
  const rect = svField.getBoundingClientRect();
  setCurrentHsv({
    ...currentHsv,
    s: clamp(((event.clientX - rect.left) / rect.width) * 100, 0, 100),
    v: clamp((1 - ((event.clientY - rect.top) / rect.height)) * 100, 0, 100),
  });
}
svField.addEventListener("pointerdown", (event) => {
  svPointer = event.pointerId;
  svField.setPointerCapture(event.pointerId);
  updateSvFromPointer(event);
});
svField.addEventListener("pointermove", updateSvFromPointer);
svField.addEventListener("pointerup", () => { svPointer = null; });
svField.addEventListener("pointercancel", () => { svPointer = null; });

function sliderKeyDelta(event, large = 10) {
  if (["ArrowRight", "ArrowUp"].includes(event.key)) return event.shiftKey ? large : 1;
  if (["ArrowLeft", "ArrowDown"].includes(event.key)) return event.shiftKey ? -large : -1;
  if (event.key === "PageUp") return large;
  if (event.key === "PageDown") return -large;
  return 0;
}
hueTrack.addEventListener("keydown", (event) => {
  const delta = sliderKeyDelta(event, 10);
  if (!delta) return;
  event.preventDefault();
  setCurrentHsv({ ...currentHsv, h: clamp(currentHsv.h + delta, 0, 360) });
});
rgbTracks.forEach((track) => track.addEventListener("keydown", (event) => {
  const delta = sliderKeyDelta(event, 10);
  if (!delta) return;
  event.preventDefault();
  const channel = track.dataset.rgbTrack;
  setCurrentRgb({ ...currentRgb, [channel]: currentRgb[channel] + delta });
}));
svField.addEventListener("keydown", (event) => {
  const delta = event.shiftKey ? 10 : 1;
  const next = { ...currentHsv };
  if (event.key === "ArrowLeft") next.s -= delta;
  else if (event.key === "ArrowRight") next.s += delta;
  else if (event.key === "ArrowDown") next.v -= delta;
  else if (event.key === "ArrowUp") next.v += delta;
  else return;
  event.preventDefault();
  setCurrentHsv(next);
});

for (const channel of ["r", "g", "b"]) {
  document.getElementById(`color-${channel}`).addEventListener("input", (event) => {
    setCurrentRgb({ ...currentRgb, [channel]: event.target.value });
  });
}
for (const channel of ["h", "s", "v"]) {
  document.getElementById(`color-${channel}`).addEventListener("input", (event) => {
    setCurrentHsv({ ...currentHsv, [channel]: event.target.value });
  });
}
document.getElementById("color-hex").addEventListener("input", (event) => {
  const hex = normalizeHex(event.target.value);
  if (hex) setCurrentRgb(hexToRgb(hex));
});

function closePicker() {
  overlay.hidden = true;
  document.body.classList.remove("color-picker-open");
  const trigger = activeTrigger;
  activeTrigger = null;
  trigger?.focus();
}

function confirmPicker() {
  if (!activeTrigger || pickerReadonly) return;
  setColorValue(activeTrigger, rgbToHex(currentRgb), { recordHistory: true });
  closePicker();
}

function openPicker(trigger) {
  activeTrigger = trigger;
  pickerReadonly = trigger.dataset.colorReadonly === "true";
  originalColor = normalizeHex(trigger.value) || "#000000";
  currentRgb = hexToRgb(originalColor);
  currentHsv = rgbToHsv(currentRgb);
  paletteEditing = false;
  overlay.querySelector("[data-color-action='edit-palette']").classList.remove("active");
  setMode(mode);
  renderPicker();
  panel.classList.toggle("color-picker-readonly", pickerReadonly);
  document.getElementById("color-picker-title").textContent = pickerReadonly ? "查看颜色" : "选择颜色";
  panel.querySelectorAll(".color-collection, .color-picker-actions").forEach((element) => {
    element.hidden = pickerReadonly;
  });
  for (const id of ["color-h", "color-s", "color-v", "color-r", "color-g", "color-b", "color-hex"]) {
    document.getElementById(id).readOnly = pickerReadonly;
  }
  [svField, hueTrack, ...rgbTracks].forEach((track) => {
    track.setAttribute("aria-disabled", String(pickerReadonly));
    track.tabIndex = pickerReadonly ? -1 : 0;
  });
  overlay.hidden = false;
  document.body.classList.add("color-picker-open");
  if (!pickerReadonly) loadPalette();
  window.requestAnimationFrame(() => panel.querySelector("[data-color-action='cancel']").focus());
}

export function setColorValue(trigger, value, { recordHistory = true } = {}) {
  const color = normalizeHex(value);
  if (!color) throw new TypeError("颜色必须是 #RRGGBB");
  trigger.value = color;
  renderTrigger(trigger);
  if (recordHistory) {
    recentColors = updateRecentColors(recentColors, color, 10);
    persistLocalColors();
  }
  trigger.dispatchEvent(new Event("input", { bubbles: true }));
  trigger.dispatchEvent(new Event("change", { bubbles: true }));
}

export function refreshColorTrigger(trigger) {
  renderTrigger(trigger);
}

modeButtons.forEach((button) => button.addEventListener("click", () => setMode(button.dataset.colorMode)));
overlay.addEventListener("click", (event) => {
  if (event.target === overlay) closePicker();
  const action = event.target.closest("[data-color-action]")?.dataset.colorAction;
  if (action === "cancel") closePicker();
  else if (action === "confirm") confirmPicker();
  else if (action === "favorite") addFavorite(event.target.closest("[data-color-action='favorite']"));
  else if (action === "edit-palette") {
    paletteEditing = !paletteEditing;
    event.target.classList.toggle("active", paletteEditing);
    renderSwatches();
  }
});
window.addEventListener("keydown", (event) => {
  if (overlay.hidden) return;
  if (event.key === "Escape") {
    event.preventDefault();
    closePicker();
    return;
  }
  if (event.key !== "Tab") return;
  const focusable = Array.from(panel.querySelectorAll("button:not(:disabled), input:not(:disabled), [tabindex='0']"))
    .filter((element) => !element.closest("[hidden]") && element.getClientRects().length > 0);
  const first = focusable[0];
  const last = focusable[focusable.length - 1];
  if (event.shiftKey && document.activeElement === first) {
    event.preventDefault();
    last.focus();
  } else if (!event.shiftKey && document.activeElement === last) {
    event.preventDefault();
    first.focus();
  }
});

document.querySelectorAll("[data-color-picker]").forEach((trigger) => {
  renderTrigger(trigger);
  trigger.addEventListener("click", () => openPicker(trigger));
});