/*
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
 *
 * Copyright 2017 Olaf Wintermann. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 *   1. Redistributions of source code must retain the above copyright
 *      notice, this list of conditions and the following disclaimer.
 *
 *   2. Redistributions in binary form must reproduce the above copyright
 *      notice, this list of conditions and the following disclaimer in the
 *      documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdarg.h>

#include "../common/context.h"
#include "../common/object.h"
#include "container.h"

#include "tree.h"


void* ui_strmodel_getvalue(void *elm, int column) {
    return column == 0 ? elm : NULL;
}


UIWIDGET ui_listview_str(UiObject *obj, UiList *list, ui_callback f, void *udata) {
    return ui_listview(obj, list, ui_strmodel_getvalue, f, udata);
}

UIWIDGET ui_listview_var(UiObject *obj, UiVar *var, ui_getvaluefunc getvalue, ui_callback f, void *udata) {
    // create treeview
    GtkWidget *view = gtk_tree_view_new();
    GtkCellRenderer *renderer = gtk_cell_renderer_text_new();
    GtkTreeViewColumn *column = gtk_tree_view_column_new_with_attributes(NULL, renderer, "text", 0, NULL);
    gtk_tree_view_append_column(GTK_TREE_VIEW(view), column);
    
    gtk_tree_view_set_headers_visible(GTK_TREE_VIEW(view), FALSE);
#ifdef UI_GTK3
#if GTK_MINOR_VERSION >= 8
    gtk_tree_view_set_activate_on_single_click(GTK_TREE_VIEW(view), TRUE);
#else
    // TODO: implement for older gtk3
#endif
#else
    // TODO: implement for gtk2
#endif
    
    UiModel *model = ui_model(obj->ctx, UI_STRING, "", -1);
    model->getvalue = getvalue;
    UiList *list = var->value;
    UiListModel *listmodel = ui_list_model_new(obj, var, model);
    gtk_tree_view_set_model(GTK_TREE_VIEW(view), GTK_TREE_MODEL(listmodel));
    
    UiListView *listview = malloc(sizeof(UiListView));
    listview->obj = obj;
    listview->widget = view;
    listview->var = var;
    listview->model = model;
    g_signal_connect(
                view,
                "destroy",
                G_CALLBACK(ui_listview_destroy),
                listview);
    
    // bind var
    list->update = ui_listview_update;
    list->obj = listview;
    
    // add callback
    if(f) {
        UiTreeEventData *event = ui_malloc(obj->ctx, sizeof(UiTreeEventData));
        event->obj = obj;
        event->userdata = udata;
        event->activate = f;
        event->selection = NULL;

        g_signal_connect(
                view,
                "row-activated",
                G_CALLBACK(ui_listview_activate_event),
                event);
    }
    
    // add widget to the current container
    GtkWidget *scroll_area = gtk_scrolled_window_new(NULL, NULL);
    gtk_scrolled_window_set_policy(
            GTK_SCROLLED_WINDOW(scroll_area),
            GTK_POLICY_AUTOMATIC,
            GTK_POLICY_AUTOMATIC); // GTK_POLICY_ALWAYS  
    gtk_container_add(GTK_CONTAINER(scroll_area), view);
    
    UiContainer *ct = uic_get_current_container(obj);
    ct->add(ct, scroll_area, TRUE);
    
    // ct->current should point to view, not scroll_area, to make it possible
    // to add a context menu
    ct->current = view;
    
    return scroll_area;
}

UIWIDGET ui_listview(UiObject *obj, UiList *list, ui_getvaluefunc getvalue, ui_callback f, void *udata) {
    UiVar *var = malloc(sizeof(UiVar));
    var->value = list;
    var->type = UI_VAR_SPECIAL;
    return ui_listview_var(obj, var, getvalue, f, udata);
}

UIWIDGET ui_listview_nv(UiObject *obj, char *varname, ui_getvaluefunc getvalue, ui_callback f, void *udata) {
    UiVar *var = uic_create_var(obj->ctx, varname, UI_VAR_LIST);
    if(var) {
        return ui_listview_var(obj, var, getvalue, f, udata);
    } else {
        // TODO: error
    }
    return NULL;
}

static void drag_begin(GtkWidget *widget, GdkDragContext *context, gpointer udata) {
    printf("drag begin\n");
    
}

static void drag_end(
        GtkWidget *widget,
        GdkDragContext *context,
        guint time,
        gpointer udata)
{
    printf("drag end\n");
    
}

static GtkTargetEntry targetentries[] =
    {
      { "STRING",        0, 0 },
      { "text/plain",    0, 1 },
      { "text/uri-list", 0, 2 },
    };

UIWIDGET ui_table_var(UiObject *obj, UiVar *var, UiModel *model, UiListCallbacks cb) {
    // create treeview
    GtkWidget *view = gtk_tree_view_new();
    
    int addi = 0;
    for(int i=0;i<model->columns;i++) {
        GtkTreeViewColumn *column = NULL;
        if(model->types[i] == UI_ICON_TEXT) {
            column = gtk_tree_view_column_new();
            gtk_tree_view_column_set_title(column, model->titles[i]);
            
            GtkCellRenderer *iconrenderer = gtk_cell_renderer_pixbuf_new();
            GtkCellRenderer *textrenderer = gtk_cell_renderer_text_new();
            
            gtk_tree_view_column_pack_end(column, textrenderer, TRUE);
            gtk_tree_view_column_pack_start(column, iconrenderer, FALSE);
            
            
            gtk_tree_view_column_add_attribute(column, iconrenderer, "pixbuf", i);
            gtk_tree_view_column_add_attribute(column, textrenderer, "text", i+1);
            
            addi++;
        } else {
            GtkCellRenderer *renderer = gtk_cell_renderer_text_new();
            column = gtk_tree_view_column_new_with_attributes(
                model->titles[i],
                renderer,
                "text",
                i + addi,
                NULL);
        }
        gtk_tree_view_column_set_resizable(column, TRUE);
        gtk_tree_view_append_column(GTK_TREE_VIEW(view), column);
    }
    
    //gtk_tree_view_set_headers_visible(GTK_TREE_VIEW(view), FALSE);
#ifdef UI_GTK3
    //gtk_tree_view_set_activate_on_single_click(GTK_TREE_VIEW(view), TRUE);
#else
    
#endif
    
    UiList *list = var->value;
    UiListModel *listmodel = ui_list_model_new(obj, var, model);
    gtk_tree_view_set_model(GTK_TREE_VIEW(view), GTK_TREE_MODEL(listmodel));
    
    //g_signal_connect(view, "drag-begin", G_CALLBACK(drag_begin), NULL);
    //g_signal_connect(view, "drag-end", G_CALLBACK(drag_end), NULL);
       
    // add TreeView as observer to the UiList to update the TreeView if the
    // data changes
    UiListView *tableview = malloc(sizeof(UiListView));
    tableview->obj = obj;
    tableview->widget = view;
    tableview->var = var;
    tableview->model = model;
    g_signal_connect(
                view,
                "destroy",
                G_CALLBACK(ui_listview_destroy),
                tableview);
    
    // bind var
    list->update = ui_listview_update;
    list->obj = tableview;
    
    // add callback
    UiTreeEventData *event = ui_malloc(obj->ctx, sizeof(UiTreeEventData));
    event->obj = obj;
    event->activate = cb.activate;
    event->selection = cb.selection;
    event->userdata = cb.userdata;
    if(cb.activate) {
        g_signal_connect(
                view,
                "row-activated",
                G_CALLBACK(ui_listview_activate_event),
                event);
    }
    if(cb.selection) {
        GtkTreeSelection *selection = gtk_tree_view_get_selection(
                GTK_TREE_VIEW(view));
        g_signal_connect(
                selection,
                "changed",
                G_CALLBACK(ui_listview_selection_event),
                event);
    }
    // TODO: destroy callback

    
    GtkTreeSelection *selection = gtk_tree_view_get_selection (GTK_TREE_VIEW(view));
    gtk_tree_selection_set_mode(selection, GTK_SELECTION_MULTIPLE);
    
    // add widget to the current container
    GtkWidget *scroll_area = gtk_scrolled_window_new(NULL, NULL);
    gtk_scrolled_window_set_policy(
            GTK_SCROLLED_WINDOW(scroll_area),
            GTK_POLICY_AUTOMATIC,
            GTK_POLICY_AUTOMATIC); // GTK_POLICY_ALWAYS  
    gtk_container_add(GTK_CONTAINER(scroll_area), view);
    
    UiContainer *ct = uic_get_current_container(obj);
    ct->add(ct, scroll_area, TRUE);
    
    // ct->current should point to view, not scroll_area, to make it possible
    // to add a context menu
    ct->current = view;
    
    return scroll_area;
}

UIWIDGET ui_table(UiObject *obj, UiList *list, UiModel *model, UiListCallbacks cb) {
    UiVar *var = malloc(sizeof(UiVar));
    var->value = list;
    var->type = UI_VAR_SPECIAL;
    return ui_table_var(obj, var, model, cb);
}

UIWIDGET ui_table_nv(UiObject *obj, char *varname, UiModel *model, UiListCallbacks cb) {
    UiVar *var = uic_create_var(obj->ctx, varname, UI_VAR_LIST);
    if(var) {
        return ui_table_var(obj, var, model, cb);
    } else {
        // TODO: error
    }
    return NULL;
}

GtkWidget* ui_get_tree_widget(UIWIDGET widget) {
    GList *c = gtk_container_get_children(GTK_CONTAINER(widget));
    if(c) {
        return c->data;
    }
    return NULL;
}

static char** targets2array(char *target0, va_list ap, int *nelm) {
    int al = 16;
    char **targets = calloc(16, sizeof(char*));
    targets[0] = target0;
    
    int i = 1;
    char *target;
    while((target = va_arg(ap, char*)) != NULL) {
        if(i >= al) {
            al *= 2;
            targets = realloc(targets, al*sizeof(char*));
        }
        targets[i] = target;
        i++;
    }
    
    *nelm = i;
    return targets;
}

static GtkTargetEntry* targetstr2gtktargets(char **str, int nelm) {
    GtkTargetEntry *targets = calloc(nelm, sizeof(GtkTargetEntry));
    for(int i=0;i<nelm;i++) {
        targets[i].target = str[i];
    }
    return targets;
}

void ui_table_dragsource(UIWIDGET tablewidget, int actions, char *target0, ...) { 
    va_list ap;
    va_start(ap, target0);
    int nelm;
    char **targets = targets2array(target0, ap, &nelm);
    va_end(ap);
    ui_table_dragsource_a(tablewidget, actions, targets, nelm);
    free(targets);
}

void ui_table_dragsource_a(UIWIDGET tablewidget, int actions, char **targets, int nelm) {
    GtkTargetEntry* t = targetstr2gtktargets(targets, nelm);
    gtk_tree_view_enable_model_drag_source(
            GTK_TREE_VIEW(ui_get_tree_widget(tablewidget)),
            GDK_BUTTON1_MASK,
            t,
            nelm,
            GDK_ACTION_COPY|GDK_ACTION_MOVE|GDK_ACTION_LINK);
    free(t);
}

void ui_table_dragdest(UIWIDGET tablewidget, int actions, char *target0, ...) {
    va_list ap;
    va_start(ap, target0);
    int nelm;
    char **targets = targets2array(target0, ap, &nelm);
    va_end(ap);
    ui_table_dragdest_a(tablewidget, actions, targets, nelm);
    free(targets);
}

void ui_table_dragdest_a(UIWIDGET tablewidget, int actions, char **targets, int nelm) {
    GtkTargetEntry* t = targetstr2gtktargets(targets, nelm);
    gtk_tree_view_enable_model_drag_dest(
            GTK_TREE_VIEW(ui_get_tree_widget(tablewidget)),
            t,
            nelm,
            GDK_ACTION_COPY|GDK_ACTION_MOVE|GDK_ACTION_LINK);
    free(t);
}

void ui_listview_update(UiList *list, int i) {
    UiListView *view = list->obj;
    UiListModel *model = ui_list_model_new(view->obj, view->var, view->model);
    gtk_tree_view_set_model(GTK_TREE_VIEW(view->widget), GTK_TREE_MODEL(model));
    g_object_unref(G_OBJECT(model));
    // TODO: free old model
}

void ui_listview_destroy(GtkWidget *w, UiListView *v) {
    gtk_tree_view_set_model(GTK_TREE_VIEW(w), NULL);
    ui_destroy_boundvar(v->obj->ctx, v->var);
    // TODO: destroy model?
    free(v);
}

void ui_combobox_destroy(GtkWidget *w, UiListView *v) {
    gtk_combo_box_set_model(GTK_COMBO_BOX(w), NULL);
    ui_destroy_boundvar(v->obj->ctx, v->var);
    // TODO: destroy model?
    free(v);
}


void ui_listview_activate_event(
        GtkTreeView *treeview,
        GtkTreePath *path,
        GtkTreeViewColumn *column,
        UiTreeEventData *event)
{
    UiListSelection *selection = ui_listview_selection(
            gtk_tree_view_get_selection(treeview),
            event);
    
    UiEvent e;
    e.obj = event->obj;
    e.window = event->obj->window;
    e.document = event->obj->ctx->document;
    e.eventdata = selection;
    e.intval = selection->count > 0 ? selection->rows[0] : -1;
    event->activate(&e, event->userdata);
    
    if(selection->count > 0) {
        free(selection->rows);
    }
    free(selection);
}

void ui_listview_selection_event(
        GtkTreeSelection *treeselection,
        UiTreeEventData *event)
{
    UiListSelection *selection = ui_listview_selection(treeselection, event);
    
    UiEvent e;
    e.obj = event->obj;
    e.window = event->obj->window;
    e.document = event->obj->ctx->document;
    e.eventdata = selection;
    e.intval = selection->count > 0 ? selection->rows[0] : -1;
    event->selection(&e, event->userdata);
    
    if(selection->count > 0) {
        free(selection->rows);
    }
    free(selection);
}

UiListSelection* ui_listview_selection(
        GtkTreeSelection *selection,
        UiTreeEventData *event)
{
    GList *rows = gtk_tree_selection_get_selected_rows(selection, NULL);
    
    UiListSelection *ls = malloc(sizeof(UiListSelection));
    ls->count = g_list_length(rows);
    ls->rows = calloc(ls->count, sizeof(int));
    GList *r = rows;
    int i = 0;
    while(r) {
        GtkTreePath *path = r->data;
        ls->rows[i] = ui_tree_path_list_index(path);
        r = r->next;
        i++;
    }
    return ls;
}

int ui_tree_path_list_index(GtkTreePath *path) {
    int depth = gtk_tree_path_get_depth(path);
    if(depth == 0) {
        fprintf(stderr, "UiError: treeview selection: depth == 0\n");
        return -1;
    }
    int *indices = gtk_tree_path_get_indices(path);
    return indices[depth - 1];
}


/* --------------------------- ComboBox ---------------------------  */

UIWIDGET ui_combobox_str(UiObject *obj, UiList *list, ui_callback f, void *udata) {
    return ui_combobox(obj, list, ui_strmodel_getvalue, f, udata);
}

UIWIDGET ui_combobox(UiObject *obj, UiList *list, ui_getvaluefunc getvalue, ui_callback f, void *udata) {
    UiVar *var = malloc(sizeof(UiVar));
    var->value = list;
    var->type = UI_VAR_SPECIAL;
    return ui_combobox_var(obj, var, getvalue, f, udata);
}

UIWIDGET ui_combobox_nv(UiObject *obj, char *varname, ui_getvaluefunc getvalue, ui_callback f, void *udata) {
    UiVar *var = uic_create_var(obj->ctx, varname, UI_VAR_LIST);
    if(var) {
        return ui_combobox_var(obj, var, getvalue, f, udata);
    } else {
        // TODO: error
    }
    return NULL;
}

UIWIDGET ui_combobox_var(UiObject *obj, UiVar *var, ui_getvaluefunc getvalue, ui_callback f, void *udata) {
    UiModel *model = ui_model(obj->ctx, UI_STRING, "", -1);
    model->getvalue = getvalue;
    UiListModel *listmodel = ui_list_model_new(obj, var, model);
    
    GtkWidget *combobox = ui_create_combobox(obj, listmodel, f, udata);
    UiContainer *ct = uic_get_current_container(obj);
    ct->add(ct, combobox, FALSE);
    return combobox;
}

GtkWidget* ui_create_combobox(UiObject *obj, UiListModel *model, ui_callback f, void *udata) {
    GtkWidget *combobox = gtk_combo_box_new_with_model(GTK_TREE_MODEL(model));
    
    UiListView *uicbox = malloc(sizeof(UiListView));
    uicbox->obj = obj;
    uicbox->widget = combobox;
    uicbox->var = model->var;
    uicbox->model = model->model;
    
    g_signal_connect(
                combobox,
                "destroy",
                G_CALLBACK(ui_combobox_destroy),
                uicbox);
    
    // bind var
    UiList *list = model->var->value;
    list->update = ui_combobox_modelupdate;
    list->obj = uicbox;
    
    GtkCellRenderer *renderer = gtk_cell_renderer_text_new();
    gtk_cell_layout_pack_start(GTK_CELL_LAYOUT(combobox), renderer, TRUE);
    gtk_cell_layout_set_attributes(
            GTK_CELL_LAYOUT(combobox),
            renderer,
            "text",
            0,
            NULL);
    gtk_combo_box_set_active(GTK_COMBO_BOX(combobox), 0);
    
    // add callback
    if(f) {
        UiEventData *event = ui_malloc(obj->ctx, sizeof(UiEventData));
        event->obj = obj;
        event->userdata = udata;
        event->callback = f;
        event->value = 0;

        g_signal_connect(
                combobox,
                "changed",
                G_CALLBACK(ui_combobox_change_event),
                event);
    }
    
    return combobox;
}

void ui_combobox_change_event(GtkComboBox *widget, UiEventData *e) {
    UiEvent event;
    event.obj = e->obj;
    event.window = event.obj->window;
    event.document = event.obj->ctx->document;
    event.eventdata = NULL;
    event.intval = gtk_combo_box_get_active(widget);
    e->callback(&event, e->userdata);
}

void ui_combobox_modelupdate(UiList *list, int i) {
    UiListView *view = list->obj;
    UiListModel *model = ui_list_model_new(view->obj, view->var, view->model);
    gtk_combo_box_set_model(GTK_COMBO_BOX(view->widget), GTK_TREE_MODEL(model));
}