/*
Copyright 2014 matrix.org

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/

angular.module('RoomController', ['ngSanitize', 'mUtilities'])
.controller('RoomController', ['$scope', '$http', '$timeout', '$routeParams', '$location', 'matrixService', 'eventStreamService', 'eventHandlerService', 'mFileUpload', 'mUtilities',
                               function($scope, $http, $timeout, $routeParams, $location, matrixService, eventStreamService, eventHandlerService, mFileUpload, mUtilities) {
   'use strict';
    var MESSAGES_PER_PAGINATION = 30;
    var THUMBNAIL_SIZE = 320;

    // Room ids. Computed and resolved in onInit
    $scope.room_id = undefined;
    $scope.room_alias = undefined;

    $scope.state = {
        user_id: matrixService.config().user_id,
        events_from: "END", // when to start the event stream from.
        earliest_token: "END", // stores how far back we've paginated.
        first_pagination: true, // this is toggled off when the first pagination is done
        can_paginate: true, // this is toggled off when we run out of items
        paginating: false, // used to avoid concurrent pagination requests pulling in dup contents
        stream_failure: undefined, // the response when the stream fails
        // FIXME: sending has been disabled, as surely messages should be sent in the background rather than locking the UI synchronously --Matthew
        sending: false // true when a message is being sent. It helps to disable the UI when a process is running
    };
    $scope.members = {};
    $scope.autoCompleting = false;
    $scope.autoCompleteIndex = 0;    
    $scope.autoCompleteOriginal = "";

    $scope.imageURLToSend = "";
    $scope.userIDToInvite = "";
    
    var scrollToBottom = function() {
        console.log("Scrolling to bottom");
        $timeout(function() {
            var objDiv = document.getElementById("messageTableWrapper");
            objDiv.scrollTop = objDiv.scrollHeight;
        }, 0);
    };
    
    $scope.$on(eventHandlerService.MSG_EVENT, function(ngEvent, event, isLive) {
        if (isLive && event.room_id === $scope.room_id) {
            scrollToBottom();
            
            if (window.Notification) {
                // FIXME: we should also notify based on a timer or other heuristics
                // rather than the window being minimised
                if (document.hidden) {
                    var notification = new window.Notification(
                        ($scope.members[event.user_id].displayname || event.user_id) +
                        " (" + ($scope.room_alias || $scope.room_id) + ")", // FIXME: don't leak room_ids here
                    {
                        "body": event.content.body,
                        "icon": $scope.members[event.user_id].avatar_url,
                    });
                    $timeout(function() {
                        notification.close();
                    }, 5 * 1000);
                }
            }
        }
    });
    
    $scope.$on(eventHandlerService.MEMBER_EVENT, function(ngEvent, event, isLive) {
        updateMemberList(event);
    });
    
    $scope.$on(eventHandlerService.PRESENCE_EVENT, function(ngEvent, event, isLive) {
        updatePresence(event);
    });
    
    $scope.paginateMore = function() {
        if ($scope.state.can_paginate) {
            // console.log("Paginating more.");
            paginate(MESSAGES_PER_PAGINATION);
        }
    };
        
    var paginate = function(numItems) {
        // console.log("paginate " + numItems);
        if ($scope.state.paginating || !$scope.room_id) {
            return;
        }
        else {
            $scope.state.paginating = true;
        }
        // console.log("paginateBackMessages from " + $scope.state.earliest_token + " for " + numItems);
        var originalTopRow = $("#messageTable>tbody>tr:first")[0];
        matrixService.paginateBackMessages($scope.room_id, $scope.state.earliest_token, numItems).then(
            function(response) {
                eventHandlerService.handleEvents(response.data.chunk, false);
                $scope.state.earliest_token = response.data.end;
                if (response.data.chunk.length < MESSAGES_PER_PAGINATION) {
                    // no more messages to paginate. this currently never gets turned true again, as we never
                    // expire paginated contents in the current implementation.
                    $scope.state.can_paginate = false;
                }
                
                $scope.state.paginating = false;
                
                var wrapper = $("#messageTableWrapper")[0];
                var table = $("#messageTable")[0];
                // console.log("wrapper height=" + wrapper.clientHeight + ", table scrollHeight=" + table.scrollHeight);
                
                if ($scope.state.can_paginate) {
                    // check we don't have to pull in more messages
                    // n.b. we dispatch through a timeout() to allow the digest to run otherwise the .height methods are stale
                    $timeout(function() {
                        if (table.scrollHeight < wrapper.clientHeight) {
                            paginate(MESSAGES_PER_PAGINATION);
                            scrollToBottom();                            
                        }
                    }, 0);
                }
                
                if ($scope.state.first_pagination) {
                    scrollToBottom();
                    $scope.state.first_pagination = false;
                }
                else {
                    // lock the scroll position
                    $timeout(function() {
                        // FIXME: this risks a flicker before the scrollTop is actually updated, but we have to
                        // dispatch it into a function in order to first update the layout.  The right solution
                        // might be to implement it as a directive, more like
                        // http://stackoverflow.com/questions/23736647/how-to-retain-scroll-position-of-ng-repeat-in-angularjs
                        // however, this specific solution breaks because it measures the rows height before
                        // the contents are interpolated.
                        wrapper.scrollTop = originalTopRow ? (originalTopRow.offsetTop + wrapper.scrollTop) : 0;
                    }, 0);
                }
            },
            function(error) {
                console.log("Failed to paginateBackMessages: " + JSON.stringify(error));
                $scope.state.paginating = false;
            }
        );
    };

    var updateMemberList = function(chunk) {
        var isNewMember = !(chunk.target_user_id in $scope.members);
        if (isNewMember) {
            // FIXME: why are we copying these fields around inside chunk?
            if ("state" in chunk.content) {
                chunk.presenceState = chunk.content.state; // why is this renamed?
            }
            if ("mtime_age" in chunk.content) {
                chunk.mtime_age = chunk.content.mtime_age;
            }
            // Once the HS reliably returns the displaynames & avatar_urls for both
            // local and remote users, we should use this rather than the evalAsync block
            // below
            if ("displayname" in chunk.content) {
                chunk.displayname = chunk.content.displayname;
            }
            if ("avatar_url" in chunk.content) {
                chunk.avatar_url = chunk.content.avatar_url;
            }
            $scope.members[chunk.target_user_id] = chunk;

/*
            // Stale code for explicitly hammering the homeserver for every displayname & avatar_url
            
            // get their display name and profile picture and set it to their
            // member entry in $scope.members. We HAVE to use $timeout with 0 delay 
            // to make this function run AFTER the current digest cycle, else the 
            // response may update a STALE VERSION of the member list (manifesting
            // as no member names appearing, or appearing sporadically).
            $scope.$evalAsync(function() {
                matrixService.getDisplayName(chunk.target_user_id).then(
                    function(response) {
                        var member = $scope.members[chunk.target_user_id];
                        if (member !== undefined) {
                            member.displayname = response.data.displayname;
                        }
                    }
                ); 
                matrixService.getProfilePictureUrl(chunk.target_user_id).then(
                    function(response) {
                         var member = $scope.members[chunk.target_user_id];
                         if (member !== undefined) {
                            member.avatar_url = response.data.avatar_url;
                         }
                    }
                );
            });
*/            
        }
        else {
            // selectively update membership else it will nuke the picture and displayname too :/
            var member = $scope.members[chunk.target_user_id];
            member.content.membership = chunk.content.membership;
        }
    }

    var updatePresence = function(chunk) {
        if (!(chunk.content.user_id in $scope.members)) {
            console.log("updatePresence: Unknown member for chunk " + JSON.stringify(chunk));
            return;
        }
        var member = $scope.members[chunk.content.user_id];

        // XXX: why not just pass the chunk straight through?
        if ("state" in chunk.content) {
            member.presenceState = chunk.content.state;
        }

        if ("mtime_age" in chunk.content) {
            // FIXME: should probably keep updating mtime_age in realtime like FB does
            member.mtime_age = chunk.content.mtime_age;
        }

        // this may also contain a new display name or avatar url, so check.
        if ("displayname" in chunk.content) {
            member.displayname = chunk.content.displayname;
        }

        if ("avatar_url" in chunk.content) {
            member.avatar_url = chunk.content.avatar_url;
        }
    }

    $scope.send = function() {
        if ($scope.textInput == "") {
            return;
        }

        $scope.state.sending = true;
        
        // Send the text message
        var promise;
        // FIXME: handle other commands too
        if ($scope.textInput.indexOf("/me") == 0) {
            promise = matrixService.sendEmoteMessage($scope.room_id, $scope.textInput.substr(4));
        }
        else {
            promise = matrixService.sendTextMessage($scope.room_id, $scope.textInput);
        }
        
        promise.then(
            function() {
                console.log("Sent message");
                $scope.textInput = "";
                $scope.state.sending = false;
            },
            function(error) {
                $scope.feedback = "Failed to send: " + error.data.error;
                $scope.state.sending = false;
            });
    };

    $scope.onInit = function() {
        console.log("onInit");
        
        // Does the room ID provided in the URL?
        var room_id_or_alias;
        if ($routeParams.room_id_or_alias) {
            room_id_or_alias = decodeURIComponent($routeParams.room_id_or_alias);
        }

        if (room_id_or_alias && '!' === room_id_or_alias[0]) {
            // Yes. We can start right now
            $scope.room_id = room_id_or_alias;
            $scope.room_alias = matrixService.getRoomIdToAliasMapping($scope.room_id);
            onInit2();
        }
        else {
            // No. The URL contains the room alias. Get this alias.
            if (room_id_or_alias) {
                // The room alias was passed urlencoded, use it as is
                $scope.room_alias = room_id_or_alias;
            }
            else  {
                // Else get the room alias by hand from the URL
                // ie: extract #public:localhost:8080 from http://127.0.0.1:8000/#/room/#public:localhost:8080
                if (3 === location.hash.split("#").length) {
                    $scope.room_alias = "#" + location.hash.split("#")[2];
                }
                else {
                    // In case of issue, go to the default page
                    console.log("Error: cannot extract room alias");
                    $location.path("/");
                    return;
                }
            }
            
            // Need a room ID required in Matrix API requests
            console.log("Resolving alias: " + $scope.room_alias);
            matrixService.resolveRoomAlias($scope.room_alias).then(function(response) {
                $scope.room_id = response.data.room_id;
                console.log("   -> Room ID: " + $scope.room_id);

                // Now, we can start
                onInit2();
            },
            function () {
                // In case of issue, go to the default page
                console.log("Error: cannot resolve room alias");
                $location.path("/");
            });
        }
    };

    var onInit2 = function() {
        // Join the room
        matrixService.join($scope.room_id).then(
            function() {
                console.log("Joined room "+$scope.room_id);

                // Get the current member list
                matrixService.getMemberList($scope.room_id).then(
                    function(response) {
                        for (var i = 0; i < response.data.chunk.length; i++) {
                            var chunk = response.data.chunk[i];
                            updateMemberList(chunk);
                        }
                        eventStreamService.resume();
                    },
                    function(error) {
                        $scope.feedback = "Failed get member list: " + error.data.error;
                    }
                );
                
                paginate(MESSAGES_PER_PAGINATION);
            },
            function(reason) {
                $scope.feedback = "Can't join room: " + reason;
            });
    }; 
    
    $scope.inviteUser = function(user_id) {
        
        matrixService.invite($scope.room_id, user_id).then(
            function() {
                console.log("Invited.");
                $scope.feedback = "Request for invitation succeeds";
            },
            function(reason) {
                $scope.feedback = "Failure: " + reason;
            });
    };

    // Open the user profile page
    $scope.goToUserPage = function(user_id) {
        $location.url("/user/" + user_id);
    };

    $scope.leaveRoom = function() {
        
        matrixService.leave($scope.room_id).then(
            function(response) {
                console.log("Left room ");
                $location.path("rooms");
            },
            function(error) {
                $scope.feedback = "Failed to leave room: " + error.data.error;
            });
    };

    $scope.sendImage = function(url, body) {
        $scope.state.sending = true;

        matrixService.sendImageMessage($scope.room_id, url, body).then(
            function() {
                console.log("Image sent");
                $scope.state.sending = false;
            },
            function(error) {
                $scope.feedback = "Failed to send image: " + error.data.error;
                $scope.state.sending = false;
            });
    };
    
    $scope.imageFileToSend;
    $scope.$watch("imageFileToSend", function(newValue, oldValue) {
        if ($scope.imageFileToSend) {

            $scope.state.sending = true;

            // Upload this image with its thumbnail to Internet
            mFileUpload.uploadImageAndThumbnail($scope.imageFileToSend, THUMBNAIL_SIZE).then(
                function(imageMessage) {
                    // imageMessage is complete message structure, send it as is
                    matrixService.sendMessage($scope.room_id, undefined, imageMessage).then(
                        function() {
                            console.log("Image message sent");
                            $scope.state.sending = false;
                        },
                        function(error) {
                            $scope.feedback = "Failed to send image message: " + error.data.error;
                            $scope.state.sending = false;
                        });
                },
                function(error) {
                    $scope.feedback = "Can't upload image";
                    $scope.state.sending = false;
                }
            );
        }
    });
    
    $scope.loadMoreHistory = function() {
        paginate(MESSAGES_PER_PAGINATION);
    };
}]);