/*
 Copyright (C) 2015 by Marijn Haverbeke <marijnh@gmail.com> and others

 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal
 in the Software without restriction, including without limitation the rights
 to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 copies of the Software, and to permit persons to whom the Software is
 furnished to do so, subject to the following conditions:

 The above copyright notice and this permission notice shall be included in
 all copies or substantial portions of the Software.

 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 THE SOFTWARE.
 */

(function (mod) {
    if (typeof exports == "object" && typeof module == "object") // CommonJS
        mod(require("codemirror"));
    else if (typeof define == "function" && define.amd) // AMD
        define(["codemirror"], mod);
    else // Plain browser env
        mod(CodeMirror);
})(function (CodeMirror) {
    "use strict";

    var HINT_ELEMENT_CLASS = "CodeMirror-hint";
    var ACTIVE_HINT_ELEMENT_CLASS = "CodeMirror-hint-active";

    // This is the old interface, kept around for now to stay
    // backwards-compatible.
    CodeMirror.showHint = function (cm, getHints, options) {
        if (!getHints) return cm.showHint(options);
        if (options && options.async) getHints.async = true;
        var newOpts = {hint: getHints};
        if (options) for (var prop in options) newOpts[prop] = options[prop];
        return cm.showHint(newOpts);
    };

    var asyncRunID = 0;

    function retrieveHints(getter, cm, options, then) {
        if (getter.async) {
            var id = ++asyncRunID;
            getter(cm, function (hints) {
                if (asyncRunID == id) then(hints);
            }, options);
        } else {
            then(getter(cm, options));
        }
    }

    CodeMirror.defineExtension("showHint", function (options) {
        // We want a single cursor position.
        if (this.listSelections().length > 1 || this.somethingSelected()) return;

        if (this.state.completionActive) this.state.completionActive.close();
        var completion = this.state.completionActive = new Completion(this, options);
        var getHints = completion.options.hint;
        if (!getHints) return;

        CodeMirror.signal(this, "startCompletion", this);
        return retrieveHints(getHints, this, completion.options, function (hints) {
            completion.showHints(hints);
        });
    });

    function Completion(cm, options) {
        this.cm = cm;
        this.options = this.buildOptions(options);
        this.widget = this.onClose = null;
    }

    Completion.prototype = {
        close: function () {
            if (!this.active()) return;
            this.cm.state.completionActive = null;

            if (this.widget) this.widget.close();
            if (this.onClose) this.onClose();
            CodeMirror.signal(this.cm, "endCompletion", this.cm);
        },

        active: function () {
            return this.cm.state.completionActive == this;
        },

        pick: function (data, i) {
            var completion = data.list[i];
            if (completion.hint) completion.hint(this.cm, data, completion);
            else this.cm.replaceRange(getText(completion), completion.from || data.from,
                completion.to || data.to, "complete");
            CodeMirror.signal(data, "pick", completion);
            this.close();
        },

        showHints: function (data) {
            if (!data || !data.list.length || !this.active()) return this.close();

            if (this.options.completeSingle && data.list.length == 1)
                this.pick(data, 0);
            else
                this.showWidget(data);
        },

        showWidget: function (data) {
            this.widget = new Widget(this, data);
            CodeMirror.signal(data, "shown");

            var debounce = 0, completion = this, tick = 0;
            var closeOn = this.options.closeCharacters;
            var startPos = this.cm.getCursor(), startLen = this.cm.getLine(startPos.line).length;

            var requestAnimationFrame = window.requestAnimationFrame || function (fn) {
                    return setTimeout(fn, 1000 / 60);
                };
            var cancelAnimationFrame = window.cancelAnimationFrame || clearTimeout;

            function done() {
                if (tick == null) return;
                tick = null;
                completion.close();
                completion.cm.off("cursorActivity", activity);
                if (data) CodeMirror.signal(data, "close");
            }

            function update(myTick) {
                if (tick == null) return;
                var myTick = ++tick;
                if (data) CodeMirror.signal(data, "update");
                retrieveHints(completion.options.hint, completion.cm, completion.options,
                    function (d) {
                        finishUpdate(d, myTick);
                    });
            }

            function finishUpdate(data_, myTick) {
                if (tick != myTick) return;
                data = data_;
                var picked = completion.widget && completion.widget.picked;
                if (completion.widget) completion.widget.close();
                if (data && data.list.length) {
                    if (picked && data.list.length == 1) completion.pick(data, 0);
                    else completion.widget = new Widget(completion, data);
                }
            }

            function clearDebounce() {
                if (debounce) {
                    cancelAnimationFrame(debounce);
                    debounce = 0;
                }
            }

            function activity() {
                clearDebounce();
                var pos = completion.cm.getCursor(), line = completion.cm.getLine(pos.line);
                if (pos.line != startPos.line || line.length - pos.ch != startLen - startPos.ch ||
                    pos.ch < startPos.ch || completion.cm.somethingSelected() ||
                    (pos.ch && closeOn.test(line.charAt(pos.ch - 1)))) {
                    completion.close();
                } else {
                    debounce = requestAnimationFrame(update);
                    if (completion.widget) completion.widget.disable();
                }
            }

            this.cm.on("cursorActivity", activity);
            this.onClose = done;
        },

        buildOptions: function (options) {
            var editor = this.cm.options.hintOptions;
            var out = {};
            for (var prop in defaultOptions) out[prop] = defaultOptions[prop];
            if (editor) for (var prop in editor)
                if (editor[prop] !== undefined) out[prop] = editor[prop];
            if (options) for (var prop in options)
                if (options[prop] !== undefined) out[prop] = options[prop];
            return out;
        }
    };

    function getText(completion) {
        if (typeof completion == "string") return completion;
        else return completion.text;
    }

    function buildKeyMap(completion, handle) {
        var baseMap = {
            Up: function () {
                handle.moveFocus(-1);
            },
            Down: function () {
                handle.moveFocus(1);
            },
            PageUp: function () {
                handle.moveFocus(-handle.menuSize() + 1, true);
            },
            PageDown: function () {
                handle.moveFocus(handle.menuSize() - 1, true);
            },
            Home: function () {
                handle.setFocus(0);
            },
            End: function () {
                handle.setFocus(handle.length - 1);
            },
            Enter: handle.pick,
            Tab: handle.pick,
            Esc: handle.close
        };
        var custom = completion.options.customKeys;
        var ourMap = custom ? {} : baseMap;

        function addBinding(key, val) {
            var bound;
            if (typeof val != "string")
                bound = function (cm) {
                    return val(cm, handle);
                };
            // This mechanism is deprecated
            else if (baseMap.hasOwnProperty(val))
                bound = baseMap[val];
            else
                bound = val;
            ourMap[key] = bound;
        }

        if (custom)
            for (var key in custom) if (custom.hasOwnProperty(key))
                addBinding(key, custom[key]);
        var extra = completion.options.extraKeys;
        if (extra)
            for (var key in extra) if (extra.hasOwnProperty(key))
                addBinding(key, extra[key]);
        return ourMap;
    }

    function getHintElement(hintsElement, el) {
        while (el && el != hintsElement) {
            if (el.nodeName.toUpperCase() === "LI" && el.parentNode == hintsElement) return el;
            el = el.parentNode;
        }
    }

    function Widget(completion, data) {
        this.completion = completion;
        this.data = data;
        this.picked = false;
        var widget = this, cm = completion.cm;

        var hints = this.hints = document.createElement("ul");
        hints.className = "CodeMirror-hints";
        this.selectedHint = data.selectedHint || 0;

        var completions = data.list;
        for (var i = 0; i < completions.length; ++i) {
            var elt = hints.appendChild(document.createElement("li")), cur = completions[i];
            var className = HINT_ELEMENT_CLASS + (i != this.selectedHint ? "" : " " + ACTIVE_HINT_ELEMENT_CLASS);
            if (cur.className != null) className = cur.className + " " + className;
            elt.className = className;
            if (cur.render) cur.render(elt, data, cur);
            else elt.appendChild(document.createTextNode(cur.displayText || getText(cur)));
            elt.hintId = i;
        }

        var pos = cm.cursorCoords(completion.options.alignWithWord ? data.from : null);
        var left = pos.left, top = pos.bottom, below = true;
        hints.style.left = left + "px";
        hints.style.top = top + "px";
        // If we're at the edge of the screen, then we want the menu to appear on the left of the cursor.
        var winW = window.innerWidth || Math.max(document.body.offsetWidth, document.documentElement.offsetWidth);
        var winH = window.innerHeight || Math.max(document.body.offsetHeight, document.documentElement.offsetHeight);
        (completion.options.container || document.body).appendChild(hints);
        var box = hints.getBoundingClientRect(), overlapY = box.bottom - winH;
        if (overlapY > 0) {
            var height = box.bottom - box.top, curTop = pos.top - (pos.bottom - box.top);
            if (curTop - height > 0) { // Fits above cursor
                hints.style.top = (top = pos.top - height) + "px";
                below = false;
            } else if (height > winH) {
                hints.style.height = (winH - 5) + "px";
                hints.style.top = (top = pos.bottom - box.top) + "px";
                var cursor = cm.getCursor();
                if (data.from.ch != cursor.ch) {
                    pos = cm.cursorCoords(cursor);
                    hints.style.left = (left = pos.left) + "px";
                    box = hints.getBoundingClientRect();
                }
            }
        }
        var overlapX = box.right - winW;
        if (overlapX > 0) {
            if (box.right - box.left > winW) {
                hints.style.width = (winW - 5) + "px";
                overlapX -= (box.right - box.left) - winW;
            }
            hints.style.left = (left = pos.left - overlapX) + "px";
        }

        cm.addKeyMap(this.keyMap = buildKeyMap(completion, {
            moveFocus: function (n, avoidWrap) {
                widget.changeActive(widget.selectedHint + n, avoidWrap);
            },
            setFocus: function (n) {
                widget.changeActive(n);
            },
            menuSize: function () {
                return widget.screenAmount();
            },
            length: completions.length,
            close: function () {
                completion.close();
            },
            pick: function () {
                widget.pick();
            },
            data: data
        }));

        if (completion.options.closeOnUnfocus) {
            var closingOnBlur;
            cm.on("blur", this.onBlur = function () {
                closingOnBlur = setTimeout(function () {
                    completion.close();
                }, 100);
            });
            cm.on("focus", this.onFocus = function () {
                clearTimeout(closingOnBlur);
            });
        }

        var startScroll = cm.getScrollInfo();
        cm.on("scroll", this.onScroll = function () {
            var curScroll = cm.getScrollInfo(), editor = cm.getWrapperElement().getBoundingClientRect();
            var newTop = top + startScroll.top - curScroll.top;
            var point = newTop - (window.pageYOffset || (document.documentElement || document.body).scrollTop);
            if (!below) point += hints.offsetHeight;
            if (point <= editor.top || point >= editor.bottom) return completion.close();
            hints.style.top = newTop + "px";
            hints.style.left = (left + startScroll.left - curScroll.left) + "px";
        });

        CodeMirror.on(hints, "dblclick", function (e) {
            var t = getHintElement(hints, e.target || e.srcElement);
            if (t && t.hintId != null) {
                widget.changeActive(t.hintId);
                widget.pick();
            }
        });

        CodeMirror.on(hints, "click", function (e) {
            var t = getHintElement(hints, e.target || e.srcElement);
            if (t && t.hintId != null) {
                widget.changeActive(t.hintId);
                if (completion.options.completeOnSingleClick) widget.pick();
            }
        });

        CodeMirror.on(hints, "mousedown", function () {
            setTimeout(function () {
                cm.focus();
            }, 20);
        });

        CodeMirror.signal(data, "select", completions[0], hints.firstChild);
        return true;
    }

    Widget.prototype = {
        close: function () {
            if (this.completion.widget != this) return;
            this.completion.widget = null;
            this.hints.parentNode.removeChild(this.hints);
            this.completion.cm.removeKeyMap(this.keyMap);

            var cm = this.completion.cm;
            if (this.completion.options.closeOnUnfocus) {
                cm.off("blur", this.onBlur);
                cm.off("focus", this.onFocus);
            }
            cm.off("scroll", this.onScroll);
        },

        disable: function () {
            this.completion.cm.removeKeyMap(this.keyMap);
            var widget = this;
            this.keyMap = {
                Enter: function () {
                    widget.picked = true;
                }
            };
            this.completion.cm.addKeyMap(this.keyMap);
        },

        pick: function () {
            this.completion.pick(this.data, this.selectedHint);
        },

        changeActive: function (i, avoidWrap) {
            if (i >= this.data.list.length)
                i = avoidWrap ? this.data.list.length - 1 : 0;
            else if (i < 0)
                i = avoidWrap ? 0 : this.data.list.length - 1;
            if (this.selectedHint == i) return;
            var node = this.hints.childNodes[this.selectedHint];
            node.className = node.className.replace(" " + ACTIVE_HINT_ELEMENT_CLASS, "");
            node = this.hints.childNodes[this.selectedHint = i];
            node.className += " " + ACTIVE_HINT_ELEMENT_CLASS;
            if (node.offsetTop < this.hints.scrollTop)
                this.hints.scrollTop = node.offsetTop - 3;
            else if (node.offsetTop + node.offsetHeight > this.hints.scrollTop + this.hints.clientHeight)
                this.hints.scrollTop = node.offsetTop + node.offsetHeight - this.hints.clientHeight + 3;
            CodeMirror.signal(this.data, "select", this.data.list[this.selectedHint], node);
        },

        screenAmount: function () {
            return Math.floor(this.hints.clientHeight / this.hints.firstChild.offsetHeight) || 1;
        }
    };

    CodeMirror.registerHelper("hint", "auto", function (cm, options) {
        var helpers = cm.getHelpers(cm.getCursor(), "hint"), words;
        if (helpers.length) {
            for (var i = 0; i < helpers.length; i++) {
                var cur = helpers[i](cm, options);
                if (cur && cur.list.length) return cur;
            }
        } else if (words = cm.getHelper(cm.getCursor(), "hintWords")) {
            if (words) return CodeMirror.hint.fromList(cm, {words: words});
        } else if (CodeMirror.hint.anyword) {
            return CodeMirror.hint.anyword(cm, options);
        }
    });

    CodeMirror.registerHelper("hint", "fromList", function (cm, options) {
        var cur = cm.getCursor(), token = cm.getTokenAt(cur);
        var found = [];
        for (var i = 0; i < options.words.length; i++) {
            var word = options.words[i];
            if (word.slice(0, token.string.length) == token.string)
                found.push(word);
        }

        if (found.length) return {
            list: found,
            from: CodeMirror.Pos(cur.line, token.start),
            to: CodeMirror.Pos(cur.line, token.end)
        };
    });

    var WORD = /[\w$]+/g, RANGE = 500;

    CodeMirror.registerHelper("hint", "anyword", function (editor, options) {
        var word = options && options.word || WORD;
        var range = options && options.range || RANGE;
        var cur = editor.getCursor(), curLine = editor.getLine(cur.line);
        var start = cur.ch, end = start;
        while (end < curLine.length && word.test(curLine.charAt(end))) ++end;
        while (start && word.test(curLine.charAt(start - 1))) --start;
        var curWord = start != end && curLine.slice(start, end);

        var list = [], seen = {};

        function scan(dir) {
            var line = cur.line, end = Math.min(Math.max(line + dir * range, editor.firstLine()), editor.lastLine()) + dir;
            for (; line != end; line += dir) {
                var text = editor.getLine(line), m;
                word.lastIndex = 0;
                while (m = word.exec(text)) {
                    if ((!curWord || m[0].indexOf(curWord) == 0) && !seen.hasOwnProperty(m[0])) {
                        seen[m[0]] = true;
                        list.push(m[0]);
                    }
                }
            }
        }

        scan(-1);
        scan(1);
        return {list: list, from: CodeMirror.Pos(cur.line, start), to: CodeMirror.Pos(cur.line, end)};
    });

    CodeMirror.commands.autocomplete = CodeMirror.showHint;

    var defaultOptions = {
        hint: CodeMirror.hint.auto,
        completeSingle: true,
        alignWithWord: true,
        closeCharacters: /[\s()\[\]{};:>,]/,
        closeOnUnfocus: true,
        completeOnSingleClick: false,
        container: null,
        customKeys: null,
        extraKeys: null
    };

    CodeMirror.defineOption("hintOptions", null);
});
