// CodeMirror, copyright (c) by Marijn Haverbeke and others
// Distributed under an MIT license: https://codemirror.net/LICENSE

// declare global: DOMRect

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

    CodeMirror.defineExtension('showHint', function (options) {
        options = parseOptions(this, this.getCursor('start'), options)
        var selections = this.listSelections()
        if (selections.length > 1) return
        // By default, don't allow completion when something is selected.
        // A hint function can have a `supportsSelection` property to
        // indicate that it can handle selections.
        if (this.somethingSelected()) {
            if (!options.hint.supportsSelection) return
            // Don't try with cross-line selections
            for (var i = 0; i < selections.length; i++) if (selections[i].head.line != selections[i].anchor.line) return
        }

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

        CodeMirror.signal(this, 'startCompletion', this)
        completion.update(true)
    })

    CodeMirror.defineExtension('closeHint', function () {
        if (this.state.completionActive) this.state.completionActive.close()
    })

    function Completion(cm, options) {
        this.cm = cm
        this.options = options
        this.widget = null
        this.debounce = 0
        this.tick = 0
        this.startPos = this.cm.getCursor('start')
        this.startLen = this.cm.getLine(this.startPos.line).length - this.cm.getSelection().length

        if (this.options.updateOnCursorActivity) {
            var self = this
            cm.on(
                'cursorActivity',
                (this.activityFunc = function () {
                    self.cursorActivity()
                })
            )
        }
    }

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

    Completion.prototype = {
        close: function () {
            if (!this.active()) return
            this.cm.state.completionActive = null
            this.tick = null
            if (this.options.updateOnCursorActivity) {
                this.cm.off('cursorActivity', this.activityFunc)
            }

            if (this.widget && this.data) CodeMirror.signal(this.data, 'close')
            if (this.widget) this.widget.close()
            CodeMirror.signal(this.cm, 'endCompletion', this.cm)
        },

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

        pick: function (data, i) {
            var completion = data.list[i],
                self = this
            this.cm.operation(function () {
                if (completion.hint) completion.hint(self.cm, data, completion)
                else self.cm.replaceRange(getText(completion), completion.from || data.from, completion.to || data.to, 'complete')
                CodeMirror.signal(data, 'pick', completion)
                self.cm.scrollIntoView()
            })
            if (this.options.closeOnPick) {
                this.close()
            }
        },

        cursorActivity: function () {
            if (this.debounce) {
                cancelAnimationFrame(this.debounce)
                this.debounce = 0
            }

            var identStart = this.startPos
            if (this.data) {
                identStart = this.data.from
            }

            var pos = this.cm.getCursor(),
                line = this.cm.getLine(pos.line)
            if (
                pos.line != this.startPos.line ||
                line.length - pos.ch != this.startLen - this.startPos.ch ||
                pos.ch < identStart.ch ||
                this.cm.somethingSelected() ||
                !pos.ch ||
                this.options.closeCharacters.test(line.charAt(pos.ch - 1))
            ) {
                this.close()
            } else {
                var self = this
                this.debounce = requestAnimationFrame(function () {
                    self.update()
                })
                if (this.widget) this.widget.disable()
            }
        },

        update: function (first) {
            if (this.tick == null) return
            var self = this,
                myTick = ++this.tick
            fetchHints(this.options.hint, this.cm, this.options, function (data) {
                if (self.tick == myTick) self.finishUpdate(data, first)
            })
        },

        finishUpdate: function (data, first) {
            if (this.data) CodeMirror.signal(this.data, 'update')

            var picked = (this.widget && this.widget.picked) || (first && this.options.completeSingle)
            if (this.widget) this.widget.close()

            this.data = data

            if (data && data.list.length) {
                if (picked && data.list.length == 1) {
                    this.pick(data, 0)
                } else {
                    this.widget = new Widget(this, data)
                    CodeMirror.signal(data, 'shown')
                }
            }
        },
    }

    function parseOptions(cm, pos, options) {
        var editor = 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]
        if (out.hint.resolve) out.hint = out.hint.resolve(cm, pos)
        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 mac = /Mac/.test(navigator.platform)

        if (mac) {
            baseMap['Ctrl-P'] = function () {
                handle.moveFocus(-1)
            }
            baseMap['Ctrl-N'] = function () {
                handle.moveFocus(1)
            }
        }

        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.id = 'cm-complete-' + Math.floor(Math.random(1e6))
        this.completion = completion
        this.data = data
        this.picked = false
        var widget = this,
            cm = completion.cm
        var ownerDocument = cm.getInputField().ownerDocument
        var parentWindow = ownerDocument.defaultView || ownerDocument.parentWindow

        var hints = (this.hints = ownerDocument.createElement('ul'))
        hints.setAttribute('role', 'listbox')
        hints.setAttribute('aria-expanded', 'true')
        hints.id = this.id
        var theme = completion.cm.options.theme
        hints.className = 'CodeMirror-hints ' + theme
        this.selectedHint = data.selectedHint || 0

        var completions = data.list
        for (var i = 0; i < completions.length; ++i) {
            var elt = hints.appendChild(ownerDocument.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 (i == this.selectedHint) elt.setAttribute('aria-selected', 'true')
            elt.id = this.id + '-' + i
            elt.setAttribute('role', 'option')
            if (cur.render) cur.render(elt, data, cur)
            else elt.appendChild(ownerDocument.createTextNode(cur.displayText || getText(cur)))
            elt.hintId = i
        }

        var container = completion.options.container || ownerDocument.body
        var pos = cm.cursorCoords(completion.options.alignWithWord ? data.from : null)
        var left = pos.left,
            top = pos.bottom,
            below = true
        var offsetLeft = 0,
            offsetTop = 0
        if (container !== ownerDocument.body) {
            // We offset the cursor position because left and top are relative to the offsetParent's top left corner.
            var isContainerPositioned = ['absolute', 'relative', 'fixed'].indexOf(parentWindow.getComputedStyle(container).position) !== -1
            var offsetParent = isContainerPositioned ? container : container.offsetParent
            var offsetParentPosition = offsetParent.getBoundingClientRect()
            var bodyPosition = ownerDocument.body.getBoundingClientRect()
            offsetLeft = offsetParentPosition.left - bodyPosition.left - offsetParent.scrollLeft
            offsetTop = offsetParentPosition.top - bodyPosition.top - offsetParent.scrollTop
        }
        hints.style.left = left - offsetLeft + 'px'
        hints.style.top = top - offsetTop + '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 = parentWindow.innerWidth || Math.max(ownerDocument.body.offsetWidth, ownerDocument.documentElement.offsetWidth)
        var winH = parentWindow.innerHeight || Math.max(ownerDocument.body.offsetHeight, ownerDocument.documentElement.offsetHeight)
        container.appendChild(hints)
        cm.getInputField().setAttribute('aria-autocomplete', 'list')
        cm.getInputField().setAttribute('aria-owns', this.id)
        cm.getInputField().setAttribute('aria-activedescendant', this.id + '-' + this.selectedHint)

        var box = completion.options.moveOnOverlap ? hints.getBoundingClientRect() : new DOMRect()
        var scrolls = completion.options.paddingForScrollbar ? hints.scrollHeight > hints.clientHeight + 1 : false

        // Compute in the timeout to avoid reflow on init
        var startScroll
        setTimeout(function () {
            startScroll = cm.getScrollInfo()
        })

        var 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 - offsetTop) + 'px'
                below = false
            } else if (height > winH) {
                hints.style.height = winH - 5 + 'px'
                hints.style.top = (top = pos.bottom - box.top - offsetTop) + 'px'
                var cursor = cm.getCursor()
                if (data.from.ch != cursor.ch) {
                    pos = cm.cursorCoords(cursor)
                    hints.style.left = (left = pos.left - offsetLeft) + 'px'
                    box = hints.getBoundingClientRect()
                }
            }
        }
        var overlapX = box.right - winW
        if (scrolls) overlapX += cm.display.nativeBarWidth
        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 - offsetLeft) + 'px'
        }
        if (scrolls) for (var node = hints.firstChild; node; node = node.nextSibling) node.style.paddingRight = cm.display.nativeBarWidth + '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)
                })
            )
        }

        cm.on(
            'scroll',
            (this.onScroll = function () {
                var curScroll = cm.getScrollInfo(),
                    editor = cm.getWrapperElement().getBoundingClientRect()
                if (!startScroll) startScroll = cm.getScrollInfo()
                var newTop = top + startScroll.top - curScroll.top
                var point = newTop - (parentWindow.pageYOffset || (ownerDocument.documentElement || ownerDocument.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)
        })

        // The first hint doesn't need to be scrolled to on init
        var selectedHintRange = this.getSelectedHintRange()
        if (selectedHintRange.from !== 0 || selectedHintRange.to !== 0) {
            this.scrollToActive()
        }

        CodeMirror.signal(data, 'select', completions[this.selectedHint], hints.childNodes[this.selectedHint])
        return true
    }

    Widget.prototype = {
        close: function () {
            if (this.completion.widget != this) return
            this.completion.widget = null
            if (this.hints.parentNode) this.hints.parentNode.removeChild(this.hints)
            this.completion.cm.removeKeyMap(this.keyMap)
            var input = this.completion.cm.getInputField()
            input.removeAttribute('aria-activedescendant')
            input.removeAttribute('aria-owns')

            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]
            if (node) {
                node.className = node.className.replace(' ' + ACTIVE_HINT_ELEMENT_CLASS, '')
                node.removeAttribute('aria-selected')
            }
            node = this.hints.childNodes[(this.selectedHint = i)]
            node.className += ' ' + ACTIVE_HINT_ELEMENT_CLASS
            node.setAttribute('aria-selected', 'true')
            this.completion.cm.getInputField().setAttribute('aria-activedescendant', node.id)
            this.scrollToActive()
            CodeMirror.signal(this.data, 'select', this.data.list[this.selectedHint], node)
        },

        scrollToActive: function () {
            var selectedHintRange = this.getSelectedHintRange()
            var node1 = this.hints.childNodes[selectedHintRange.from]
            var node2 = this.hints.childNodes[selectedHintRange.to]
            var firstNode = this.hints.firstChild
            if (node1.offsetTop < this.hints.scrollTop) this.hints.scrollTop = node1.offsetTop - firstNode.offsetTop
            else if (node2.offsetTop + node2.offsetHeight > this.hints.scrollTop + this.hints.clientHeight)
                this.hints.scrollTop = node2.offsetTop + node2.offsetHeight - this.hints.clientHeight + firstNode.offsetTop
        },

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

        getSelectedHintRange: function () {
            var margin = this.completion.options.scrollMargin || 0
            return {
                from: Math.max(0, this.selectedHint - margin),
                to: Math.min(this.data.list.length - 1, this.selectedHint + margin),
            }
        },
    }

    function applicableHelpers(cm, helpers) {
        if (!cm.somethingSelected()) return helpers
        var result = []
        for (var i = 0; i < helpers.length; i++) if (helpers[i].supportsSelection) result.push(helpers[i])
        return result
    }

    function fetchHints(hint, cm, options, callback) {
        if (hint.async) {
            hint(cm, callback, options)
        } else {
            var result = hint(cm, options)
            if (result && result.then) result.then(callback)
            else callback(result)
        }
    }

    function resolveAutoHints(cm, pos) {
        var helpers = cm.getHelpers(pos, 'hint'),
            words
        if (helpers.length) {
            var resolved = function (cm, callback, options) {
                var app = applicableHelpers(cm, helpers)
                function run(i) {
                    if (i == app.length) return callback(null)
                    fetchHints(app[i], cm, options, function (result) {
                        if (result && result.list.length > 0) callback(result)
                        else run(i + 1)
                    })
                }
                run(0)
            }
            resolved.async = true
            resolved.supportsSelection = true
            return resolved
        } else if ((words = cm.getHelper(cm.getCursor(), 'hintWords'))) {
            return function (cm) {
                return CodeMirror.hint.fromList(cm, { words: words })
            }
        } else if (CodeMirror.hint.anyword) {
            return function (cm, options) {
                return CodeMirror.hint.anyword(cm, options)
            }
        } else {
            return function () {}
        }
    }

    CodeMirror.registerHelper('hint', 'auto', {
        resolve: resolveAutoHints,
    })

    CodeMirror.registerHelper('hint', 'fromList', function (cm, options) {
        var cur = cm.getCursor(),
            token = cm.getTokenAt(cur)
        var term,
            from = CodeMirror.Pos(cur.line, token.start),
            to = cur
        if (token.start < cur.ch && /\w/.test(token.string.charAt(cur.ch - token.start - 1))) {
            term = token.string.substr(0, cur.ch - token.start)
        } else {
            term = ''
            from = cur
        }
        var found = []
        for (var i = 0; i < options.words.length; i++) {
            var word = options.words[i]
            if (word.slice(0, term.length) == term) found.push(word)
        }

        if (found.length) return { list: found, from: from, to: to }
    })

    CodeMirror.commands.autocomplete = CodeMirror.showHint

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

    CodeMirror.defineOption('hintOptions', null)
})