/*

 * Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>

 *

 * SPDX-License-Identifier: BSD-2-Clause

 */

#pragma once

#include <AK/ByteString.h>

#include <AK/CharacterTypes.h>

#include <AK/RefCounted.h>

#include <AK/RefPtr.h>

#include <AK/Types.h>

#include <AK/Vector.h>

#include <LibCore/MappedFile.h>

#include <LibCore/Resource.h>

#include <LibGfx/Font/Font.h>

#include <LibGfx/Size.h>

namespace Gfx {

class BitmapFont final : public Font {

public:

    virtual NonnullRefPtr<Font> clone() const override;

    virtual ErrorOr<NonnullRefPtr<Font>> try_clone() const override;

    static ErrorOr<NonnullRefPtr<BitmapFont>> create(u8 glyph_height, u8 glyph_width, bool fixed, size_t glyph_count);

    virtual FontPixelMetrics pixel_metrics() const override;

    ErrorOr<NonnullRefPtr<BitmapFont>> masked_character_set() const;

    ErrorOr<NonnullRefPtr<BitmapFont>> unmasked_character_set() const;

    static NonnullRefPtr<BitmapFont> load_from_uri(StringView);

    static ErrorOr<NonnullRefPtr<BitmapFont>> try_load_from_uri(StringView);

    static ErrorOr<NonnullRefPtr<BitmapFont>> try_load_from_resource(NonnullRefPtr<Core::Resource>);

    static ErrorOr<NonnullRefPtr<BitmapFont>> try_load_from_mapped_file(NonnullOwnPtr<Core::MappedFile>);

    static ErrorOr<NonnullRefPtr<BitmapFont>> try_load_from_stream(FixedMemoryStream&);

    ErrorOr<void> write_to_file(ByteString const& path);

    ErrorOr<void> write_to_file(NonnullOwnPtr<Core::File> file);

    ~BitmapFont();

    Bytes rows() { return m_rows; }

    Span<u8> widths() { return m_glyph_widths; }

    virtual float point_size() const override { return m_presentation_size; }

    u8 presentation_size() const override { return m_presentation_size; }

    void set_presentation_size(u8 size) { m_presentation_size = size; }

    virtual float pixel_size() const override { return m_glyph_height; }

    virtual int pixel_size_rounded_up() const override { return m_glyph_height; }

    u16 width() const override { return FontWidth::Normal; }

    u16 weight() const override { return m_weight; }

    void set_weight(u16 weight) { m_weight = weight; }

    virtual u8 slope() const override { return m_slope; }

    void set_slope(u8 slope) { m_slope = slope; }

    Optional<Glyph> glyph(u32 code_point) const override;

    Optional<Glyph> glyph(u32 code_point, GlyphSubpixelOffset) const override { return glyph(code_point); }

    Optional<Glyph> glyph_for_postscript_name(StringView, GlyphSubpixelOffset) const override { return {}; }

    float glyph_left_bearing(u32) const override { return 0; }

    Optional<float> glyph_left_bearing_for_postscript_name(StringView) const override { return {}; }

    Glyph raw_glyph(u32 code_point) const;

    bool contains_glyph(u32 code_point) const override;

    bool contains_glyph_for_postscript_name(StringView) const override { return false; }

    bool contains_raw_glyph(u32 code_point) const { return m_glyph_widths[code_point] > 0; }

    virtual float glyph_or_emoji_width(Utf8CodePointIterator&) const override;

    virtual float glyph_or_emoji_width(Utf32CodePointIterator&) const override;

    float glyphs_horizontal_kerning(u32, u32) const override { return 0.f; }

    u8 glyph_height() const { return m_glyph_height; }

    int x_height() const override { return m_x_height; }

    virtual float preferred_line_height() const override { return glyph_height() + m_line_gap; }

    virtual float glyph_width(u32 code_point) const override;

    virtual Optional<float> glyph_width_for_postscript_name(StringView) const override { return {}; }

    u8 raw_glyph_width(u32 code_point) const { return m_glyph_widths[code_point]; }

    u8 min_glyph_width() const override { return m_min_glyph_width; }

    u8 max_glyph_width() const override { return m_max_glyph_width; }

    u8 glyph_fixed_width() const override { return m_glyph_width; }

    u8 baseline() const override { return m_baseline; }

    void set_baseline(u8 baseline)

    {

        m_baseline = baseline;

        update_x_height();

    }

    u8 mean_line() const override { return m_mean_line; }

    void set_mean_line(u8 mean_line)

    {

        m_mean_line = mean_line;

        update_x_height();

    }

    virtual float width(StringView) const override;

    virtual float width(Utf8View const&) const override;

    virtual float width(Utf32View const&) const override;

    virtual int width_rounded_up(StringView) const override;

    virtual String name() const override { return m_name; }

    void set_name(String name) { m_name = move(name); }

    bool is_fixed_width() const override { return m_fixed_width; }

    void set_fixed_width(bool b) { m_fixed_width = b; }

    u8 glyph_spacing() const override { return m_glyph_spacing; }

    void set_glyph_spacing(u8 spacing) { m_glyph_spacing = spacing; }

    void set_glyph_width(u32 code_point, u8 width)

    {

        m_glyph_widths[code_point] = width;

    }

    size_t glyph_count() const override { return m_glyph_count; }

    Optional<size_t> glyph_index(u32 code_point) const;

    bool is_range_empty(u32 code_point) const { return !(m_range_mask[code_point / 256 / 8] & 1 << (code_point / 256 % 8)); }

    virtual String family() const override { return m_family; }

    void set_family(String family) { m_family = move(family); }

    virtual String variant() const override;

    virtual String qualified_name() const override;

    virtual String human_readable_name() const override { return MUST(String::formatted("{} {} {}", family(), variant(), presentation_size())); }

    virtual NonnullRefPtr<Font> with_size(float point_size) const override;

private:

    BitmapFont(String name, String family, Bytes rows, Span<u8> widths, bool is_fixed_width,

        u8 glyph_width, u8 glyph_height, u8 glyph_spacing, Bytes range_mask,

        u8 baseline, u8 mean_line, u8 presentation_size, u16 weight, u8 slope, bool owns_arrays = false);

    template<typename T>

    int unicode_view_width(T const& view) const;

    void update_x_height() { m_x_height = m_baseline - m_mean_line; }

    virtual bool has_color_bitmaps() const override { return false; }

    String m_name;

    String m_family;

    size_t m_glyph_count { 0 };

    Bytes m_range_mask;

    Vector<Optional<size_t>> m_range_indices;

    Bytes m_rows;

    Span<u8> m_glyph_widths;

    Variant<Empty, NonnullOwnPtr<Core::MappedFile>, NonnullRefPtr<Core::Resource>> m_owned_data = Empty {};

    u8 m_glyph_width { 0 };

    u8 m_glyph_height { 0 };

    u8 m_x_height { 0 };

    u8 m_min_glyph_width { 0 };

    u8 m_max_glyph_width { 0 };

    u8 m_glyph_spacing { 0 };

    u8 m_baseline { 0 };

    u8 m_mean_line { 0 };

    u8 m_presentation_size { 0 };

    u16 m_weight { 0 };

    u8 m_slope { 0 };

    u8 m_line_gap { 4 };

    bool m_fixed_width { false };

    bool m_owns_arrays { false };

};

}