const std = @import("std");
const App = @import("../app.zig");
const UI = @import("../ui.zig");
const srcery = @import("../srcery.zig");
const RangeF64 = @import("../range.zig").RangeF64;
const utils = @import("../utils.zig");
const NIDaq = @import("../ni-daq/root.zig");
const Assets = @import("../assets.zig");
const rl = @import("raylib");
const constants = @import("../constants.zig");
const Graph = @import("../graph.zig");
const UIViewRuler = @import("./view_ruler.zig");

const ViewControlsSystem = @import("./systems/view_controls.zig");

const Id = App.Id;
const remap = utils.remap;
const assert = std.debug.assert;

pub const ZoomStart = UIViewRuler.ZoomStart;

pub const Context = struct {
    ui: *UI,
    app: *App,

    view_controls: *ViewControlsSystem,
};

pub const Result = struct {
    box: *UI.Box,
};

fn createGraphBox(ctx: Context) *UI.Box {
    var ui = ctx.ui;

    return ui.createBox(.{
        .key = ui.keyFromString("Graph"),
        .size_x = UI.Sizing.initGrowFull(),
        .size_y = UI.Sizing.initGrowFull(),
        .background = srcery.black,
        .flags = &.{ .clickable, .draggable, .scrollable, .clip_view },
        .align_x = .center,
        .align_y = .center,
        .borders = .{
            .bottom = .{ .color = srcery.hard_black, .size = 4 }
        }
    });
}

fn showGraph(ctx: Context, graph_box: *UI.Box, view_id: Id) void {
    var ui = ctx.ui;
    const app = ctx.app;

    const view = app.getView(view_id).?;
    const view_opts = &view.graph_opts;


    graph_box.beginChildren();
    defer graph_box.endChildren();

    const graph_rect = graph_box.rect();

    const signal = ui.signal(graph_box);

    var sample_value_under_mouse: ?f64 = null;
    var sample_index_under_mouse: ?f64 = null;

    const mouse_x_range = RangeF64.init(0, graph_rect.width);
    const mouse_y_range = RangeF64.init(0, graph_rect.height);

    if (signal.hot) {
        sample_index_under_mouse = mouse_x_range.remapTo(view_opts.x_range, signal.relative_mouse.x);
        sample_value_under_mouse = mouse_y_range.remapTo(view_opts.y_range, signal.relative_mouse.y);
    }

    // if (ctx.view_controls.selected_tool == .move) {
        if (signal.dragged()) {
            const x_offset = mouse_x_range.remapTo(RangeF64.init(0, view_opts.x_range.size()), signal.drag.x);
            const y_offset = mouse_y_range.remapTo(RangeF64.init(0, view_opts.y_range.size()), signal.drag.y);

            ctx.view_controls.pushViewMove(
                view_id,
                view_opts.x_range.sub(x_offset),
                view_opts.y_range.add(y_offset)
            );
        }

        if (signal.scrolled() and sample_index_under_mouse != null and sample_value_under_mouse != null) {
            var scale_factor: f64 = 1;
            if (signal.scroll.y > 0) {
                scale_factor -= constants.zoom_speed;
            } else {
                scale_factor += constants.zoom_speed;
            }

            ctx.view_controls.pushViewMove(
                view_id,
                view_opts.x_range.zoom(sample_index_under_mouse.?, scale_factor),
                view_opts.y_range.zoom(sample_value_under_mouse.?, scale_factor)
            );
        }

        if (signal.flags.contains(.middle_clicked)) {
            ctx.view_controls.pushViewMove(view_id, view.available_x_range, view.available_y_range);
        }

        if (signal.flags.contains(.left_released)) {
            ctx.view_controls.pushBreakpoint();
        }
    // } else if (ctx.view_controls.selected_tool == .select) {
    //     // TODO:

    // } else if (ctx.view_controls.selected_tool == .marker) {
    //     // TODO:
    // }


    { // Render graph
        const sample_list = app.project.sample_lists.get(view.transformed_samples).?;
        Graph.drawCached(&view.graph_cache, graph_box.persistent.size, view_opts.*, sample_list);
        if (view.graph_cache.texture) |texture| {
            graph_box.texture = texture.texture;
        }
    }

    if (view_opts.x_range.size() == 0 or view_opts.y_range.size() == 0) {
        graph_box.setText("<Empty>");
        graph_box.text_color = srcery.hard_black;
        graph_box.font = .{
            .variant = .bold_italic,
            .size = ui.rem(3)
        };
    }
}

fn showToolbar(ctx: Context, view_id: Id) void {
    var ui = ctx.ui;

    const toolbar = ui.createBox(.{
        .layout_direction = .left_to_right,
        .background = srcery.hard_black,
        .size_x = UI.Sizing.initGrowFull(),
        .size_y = UI.Sizing.initFixed(.{ .pixels = ui.rem(2) })
    });
    toolbar.beginChildren();
    defer toolbar.endChildren();

    const view = ctx.app.getView(view_id).?;
    var view_name: ?[]const u8 = null;

    {
        const btn = ui.textButton("Settings");
        btn.background = srcery.hard_black;
        if (ctx.view_controls.isViewSettingsOpen(view_id)) {
            btn.borders.bottom = .{
                .color = srcery.green,
                .size = 4
            };
        }

        if (ui.signal(btn).clicked()) {
            ctx.view_controls.toggleViewSettings(view_id);
        }
    }

    switch (view.reference) {
        .channel => |channel_id| {
            const channel = ctx.app.getChannel(channel_id).?;
            const channel_name = utils.getBoundedStringZ(&channel.name);
            // const channel_type = NIDaq.getChannelType(channel_name).?;

            {
                const follow = ui.textButton("Follow");
                follow.background = srcery.hard_black;
                if (view.follow) {
                    follow.borders = UI.Borders.bottom(.{
                        .color = srcery.green,
                        .size = 4
                    });
                }
                if (ui.signal(follow).clicked()) {
                    view.follow = !view.follow;
                }
            }

            // if (channel_type == .analog_output) {
            //     const button = ui.button(ui.keyFromString("Output generation"));
            //     button.texture = Assets.output_generation;
            //     button.size.y = UI.Sizing.initGrowFull();

            //     const signal = ui.signal(button);
            //     if (signal.clicked()) {
            //         if (ctx.app.isChannelOutputing(channel_id)) {
            //             ctx.app.pushCommand(.{
            //                 .stop_output = channel_id
            //             });
            //         } else {
            //             ctx.view_controls.view_protocol_modal = view_id;
            //         }
            //     }

            //     var color = rl.Color.white;
            //     if (ctx.app.isChannelOutputing(channel_id)) {
            //         color = srcery.red;
            //     }

            //     if (signal.active) {
            //         button.texture_color = color.alpha(0.6);
            //     } else if (signal.hot) {
            //         button.texture_color = color.alpha(0.8);
            //     } else {
            //         button.texture_color = color;
            //     }
            // }

            view_name = channel_name;
        },
        .file => |file_id| {
            const file = ctx.app.getFile(file_id).?;

            view_name = std.fs.path.stem(file.path);
        },
        .mirror => |sample_list_id| {
            _ = sample_list_id;
            view_name = "Proportional";
        }
    }

    if (view.name.len > 0) {
        view_name = view.name.constSlice();
    }

    if (view_name) |text| {
        _ = ui.createBox(.{
            .size_x = UI.Sizing.initGrowFull()
        });

        _ = ui.createBox(.{
            .size_x = UI.Sizing.initFixedPixels(ui.rem(1))
        });

        const label = ui.label("{s}", .{text});
        label.size.y = UI.Sizing.initGrowFull();
        label.alignment.x = .center;
        label.alignment.y = .center;
        // TODO:
        // label.padding = UI.Padding.horizontal(ui.rem(1));

        _ = ui.createBox(.{
            .size_x = UI.Sizing.initFixedPixels(ui.rem(1))
        });
    }
}

pub fn show(ctx: Context, view_id: Id, height: UI.Sizing) !Result {
    var ui = ctx.ui;

    const view_box = ui.createBox(.{
        .key = UI.Key.initUsize(view_id.asInt()),
        .layout_direction = .top_to_bottom,
        .size_x = UI.Sizing.initGrowFull(),
        .size_y = height,
    });
    view_box.beginChildren();
    defer view_box.endChildren();

    const result = Result{
        .box = view_box
    };

    showToolbar(ctx, view_id);

    const ruler_ctx = UIViewRuler.Context{
        .ui = ctx.ui,
        .project = &ctx.app.project,
        .view_controls = ctx.view_controls
    };

    var graph_box: *UI.Box = undefined;
    var x_ruler: *UI.Box = undefined;
    var y_ruler: *UI.Box = undefined;

    {
        const container = ui.createBox(.{
            .layout_direction = .left_to_right,
            .size_x = UI.Sizing.initGrowFull(),
            .size_y = UI.Sizing.initGrowFull(),
        });
        container.beginChildren();
        defer container.endChildren();

        y_ruler = UIViewRuler.createBox(ruler_ctx, ui.keyFromString("Y ruler"), .Y);

        graph_box = createGraphBox(ctx);
    }

    {
        const container = ui.createBox(.{
            .layout_direction = .left_to_right,
            .size_x = UI.Sizing.initGrowFull(),
            .size_y = UIViewRuler.ruler_size_y,
        });
        container.beginChildren();
        defer container.endChildren();

        _ = ui.createBox(.{
            .size_x = UIViewRuler.ruler_size_x,
            .size_y = UIViewRuler.ruler_size_y,
            .background = srcery.hard_black,
        });

        x_ruler = UIViewRuler.createBox(ruler_ctx, ui.keyFromString("X ruler"), .X);
    }

    try UIViewRuler.show(ruler_ctx, x_ruler, graph_box, view_id, .X);
    try UIViewRuler.show(ruler_ctx, y_ruler, graph_box, view_id, .Y);
    showGraph(ctx, graph_box, view_id);

    return result;
}