gsichtl 0.4.0

//! Realms: a small world for a group, a floating island, a planet or a
//! floating patch of sea, with a landmark, a sky detail and sometimes a
//! waterfall or a ring.
//!
//! Realms reuse the shared inks with their own colors: body (`#`) is the
//! biome's ground, the grass or the top; dark (`d`) its soil; pupil (`p`)
//! its stone and the shadow on the right; frame (`g`) its flora; field2
//! (`t`) its liquid. Hair (`h`) is wood, white (`w`) is white, metal (`e`)
//! is a warm glow, and accent (`a`) is the realm's accent.

use crate::draws::Draws;
use crate::grid::{ACCENTS, BACKGROUNDS, Canvas, Ink, Layer, WHITE, hex};
use crate::{Avatar, Kind, Rgb};

pub(crate) const CONTEXT: &str = "gsichtl 2026-10-03 realm v1";
pub(crate) const SIDE: u8 = 20;

const WOOD: Rgb = hex(0x6f4e37);
const GLOW: Rgb = hex(0xffd43b);

/// The colors a biome gives the ground, soil, stone, flora and liquid inks.
#[derive(Clone, Copy)]
struct Biome {
    ground: Rgb,
    soil: Rgb,
    stone: Rgb,
    flora: Rgb,
    liquid: Rgb,
}

const BIOMES: [Biome; 6] = [
    // meadow
    Biome {
        ground: hex(0x51cf66),
        soil: hex(0x8c5a2b),
        stone: hex(0x5c3d1e),
        flora: hex(0x2f9e44),
        liquid: hex(0x4dabf7),
    },
    // snow
    Biome {
        ground: hex(0xf1f3f5),
        soil: hex(0x868e96),
        stone: hex(0x495057),
        flora: hex(0x2b8a3e),
        liquid: hex(0x74c0fc),
    },
    // desert
    Biome {
        ground: hex(0xf4c97a),
        soil: hex(0xd9a05b),
        stone: hex(0xa0522d),
        flora: hex(0x5c940d),
        liquid: hex(0x22b8cf),
    },
    // lava
    Biome {
        ground: hex(0x5c5f66),
        soil: hex(0x7a3b2e),
        stone: hex(0x4a2520),
        flora: hex(0xc92a2a),
        liquid: hex(0xff6b00),
    },
    // mushroom
    Biome {
        ground: hex(0xbe4bdb),
        soil: hex(0x5f3dc4),
        stone: hex(0x3b2a6b),
        flora: hex(0xf03e3e),
        liquid: hex(0x63e6be),
    },
    // crystal
    Biome {
        ground: hex(0xc5f6fa),
        soil: hex(0x3b5bdb),
        stone: hex(0x2b3a8c),
        flora: hex(0x3bc9db),
        liquid: hex(0xe599f7),
    },
];

#[derive(Clone, Copy)]
enum Shape {
    Island,
    Planet,
    Floe,
}

/// Islands twice, so half of all realms are islands.
const SHAPES: [Shape; 4] = [Shape::Island, Shape::Island, Shape::Planet, Shape::Floe];

/// Landmarks per shape; every landmark uses the accent.
const LANDMARKS: usize = 5;
/// Sky details per shape, the first of them empty.
const DETAILS: usize = 4;

// A grassy top dripping over a clod of earth, shaded on its right, with roots.
const ISLAND: Layer = Layer::at(
    10,
    1,
    &[
        "...############...",
        ".################.",
        "##################",
        "#d###dd####d###d#p",
        ".dd#ddddd#dddd#dpp",
        ".dddddddddddddddpp",
        "..ddppddddddpdppp.",
        "...ddddddppdpppp..",
        "....hdddddddpph...",
        "....h...ddpp..h...",
    ],
    false,
);

// The island's clod with a pool of water in a rim of ground.
const FLOE: Layer = Layer::at(
    10,
    1,
    &[
        "...#tttttttttt#...",
        ".#tttttttttttttt#.",
        "#ttwwttttttttwwtt#",
        "#d###dd####d###d#p",
        ".dd#ddddd#dddd#dpp",
        ".dddddddddddddddpp",
        "..ddppddddddpdppp.",
        "...ddddddppdpppp..",
        "....hdddddddpph...",
        "....h...ddpp..h...",
    ],
    false,
);

// A globe with seas and a shadowed lower right.
const PLANET: Layer = Layer::at(
    7,
    4,
    &[
        "....####....",
        "..##tt####..",
        ".##ttt#####.",
        ".#ttt####dd.",
        "#tt#####dddd",
        "##########dd",
        "####tt#####d",
        "###tttt###dd",
        ".##ttt###dd.",
        ".#######ddd.",
        "..####ddd...",
        "....dddd....",
    ],
    false,
);

// Spills from the top's right edge; island and floe.
const WATERFALL: Layer = Layer::at(
    11,
    16,
    &[
        "tt..", "ttt.", "..t.", "..t.", "..t.", "..t.", "..t.", "..t.", ".w.w",
    ],
    false,
);

// Passes behind the planet in its middle row, in front below.
const RING: Layer = Layer::new(
    12,
    &[
        "ee................ee",
        ".eee............eee.",
        "...eeeeeeeeeeeeee...",
    ],
    false,
);

const GROUND_LANDMARKS: [Layer; LANDMARKS] = [
    // tree
    Layer::at(
        1,
        4,
        &[
            "....ggg......",
            "..gggggag....",
            ".ggaggggggg..",
            "gggggggggagg.",
            "ggggggggggggg",
            ".gaggggggggg.",
            "..gggghggag..",
            "....ghhg.....",
            ".....hh......",
            ".....hhp.....",
            "....hhhpp....",
        ],
        false,
    ),
    // hut
    Layer::at(
        2,
        4,
        &[
            "........pp...",
            "...aaaaapp...",
            "..aaaaaaaaa..",
            ".aaaaaaaaaaa.",
            "aaaaaaaaaaaaa",
            ".hhhhhhhhhpp.",
            ".heehhhhhhpp.",
            ".heehhppphpp.",
            ".hhhhhppphpp.",
            ".hhhhhppphpp.",
        ],
        false,
    ),
    // tower
    Layer::at(
        1,
        6,
        &[
            "...a....", "..aaa...", ".aaaaa..", "aaaaaaa.", ".ddddpp.", ".ddeedp.", ".ddeedp.",
            ".ddddpp.", ".ddddpp.", ".dpppdp.", "ddpppddp",
        ],
        false,
    ),
    // windmill
    Layer::at(
        1,
        6,
        &[
            "ww.....ww",
            ".ww...ww.",
            "..whhhw..",
            "...hah...",
            "..whhhw..",
            ".ww.h.ww.",
            "ww.hhp.ww",
            "...hhp...",
            "..hhhpp..",
            "..heehp..",
            "..hhhpp..",
        ],
        false,
    ),
    // tent
    Layer::at(
        3,
        1,
        &[
            "......h.........",
            "......haa.......",
            "......h.........",
            ".....aaa........",
            "....aaaaa.......",
            "...aaaapaa......",
            "..aaaapppaa...e.",
            ".aaaaapppaaa.eee",
            "aaaaaapppaaa.hph",
        ],
        false,
    ),
];

const SEA_LANDMARKS: [Layer; LANDMARKS] = [
    // ship
    Layer::at(
        0,
        3,
        &[
            "......h.......",
            "......haa.....",
            "......h.......",
            ".....wh.......",
            "....wwhw......",
            "...wwwhww.....",
            "..wwwwhwww....",
            ".wwwwwhwwww...",
            "......h.......",
            "hhhhhhhhhhhhp.",
            ".hhahhahhhpp..",
            ".tthhhhhhhpptt",
        ],
        false,
    ),
    // lighthouse
    Layer::at(
        0,
        6,
        &[
            "...pp...", "..pppp..", "..weew..", "..pppp..", "...wa...", "...aa...", "..wwwa..",
            "..aaaa..", "..wwwa..", "..aaaa..", ".dpppppp", "ddpppppp",
        ],
        false,
    ),
    // serpent
    Layer::at(
        5,
        2,
        &[
            ".............gg..",
            "............gggp.",
            "............gwgaa",
            "..ggg.......gg...",
            ".gg.gg...ggg.gg..",
            "gg...gg.gg.gg.g..",
            "ww...ww.ww..wwg..",
            ".............w...",
        ],
        false,
    ),
    // palm
    Layer::at(
        1,
        4,
        &[
            "..ggg..ggg..",
            ".gg.gggg.gg.",
            "g...gggg...g",
            "....gaah....",
            ".....ah.....",
            ".....h......",
            "......h.....",
            "......h.....",
            "..#####hd...",
            ".#######dd..",
        ],
        false,
    ),
    // whale
    Layer::at(
        4,
        3,
        &[
            "....w.w........",
            ".....w.........",
            "....aaaa.......",
            "..aaaaaaaa..a.a",
            ".apaaaaaaaa.aaa",
            ".aaaaaaaaaaaa..",
            ".awwwwaaaaaa...",
            "ttwwwwwwwttt...",
        ],
        false,
    ),
];

const SPACE_LANDMARKS: [Layer; LANDMARKS] = [
    // baobab
    Layer::at(
        1,
        5,
        &[
            ".gggggggg.",
            "ggaggggagg",
            ".gg.hh.gg.",
            "....hh....",
            "...hhhh...",
            "..hhhhhh..",
        ],
        false,
    ),
    // rocket
    Layer::at(
        0,
        7,
        &[
            "..w...", ".wwa..", ".wew..", ".www..", "awwwa.", "a.e.a.", "..e...",
        ],
        false,
    ),
    // flag
    Layer::at(
        1,
        9,
        &["haaa", "haaa", "haa.", "h...", "h...", "h..."],
        false,
    ),
    // rose
    Layer::at(
        1,
        7,
        &[".www..", "w.aa.w", "w.aa.w", "w.g..w", "wgg..w", "w.g..w"],
        false,
    ),
    // dish
    Layer::at(
        1,
        6,
        &[
            "w......", ".ww..a.", ".wwwh..", "..wwww.", "...h...", "..hhh..",
        ],
        false,
    ),
];

const SKY_DETAILS: [Layer; DETAILS] = [
    // none
    Layer::new(0, &[], false),
    // cloud
    Layer::at(0, 11, &["...www..", ".wwwwww.", "wwwwwwww"], false),
    // birds
    Layer::new(
        1,
        &["ww.ww.....", "..w.......", ".......w.w", "........w."],
        false,
    ),
    // sun
    Layer::at(
        0,
        13,
        &[
            "e.....e", "..eee..", ".eeeee.", ".eeeee.", ".eeeee.", "..eee..", "e.....e",
        ],
        false,
    ),
];

const SPACE_DETAILS: [Layer; DETAILS] = [
    // none
    Layer::new(0, &[], false),
    // moon
    Layer::at(1, 1, &[".ww", "ww.", "ww.", ".ww"], false),
    // stars
    Layer::new(
        0,
        &[
            "..............e.....",
            ".e..................",
            ".................e..",
            "....................",
            "....................",
            "....................",
            "..e.................",
            "....................",
            "..................e.",
            "....................",
            "....................",
            "....................",
            "....................",
            "....................",
            "....................",
            "....................",
            "....................",
            ".e..................",
            ".................e..",
            "....................",
        ],
        false,
    ),
    // comet
    Layer::at(
        1,
        14,
        &[".....w", "....w.", "..ww..", "ee....", "ee...."],
        false,
    ),
];

#[cfg(test)]
pub(crate) const PARTS: &[&[Layer]] = &[
    &[ISLAND, FLOE, PLANET],
    &[WATERFALL, RING],
    &GROUND_LANDMARKS,
    &SEA_LANDMARKS,
    &SPACE_LANDMARKS,
    &SKY_DETAILS,
    &SPACE_DETAILS,
];

/// Indices into the palettes and part tables.
#[derive(Clone, Copy, Debug, Default)]
pub(crate) struct RealmChoice {
    bg: usize,
    shape: usize,
    biome: usize,
    landmark: usize,
    accent: usize,
    /// A waterfall on an island or a floe, a ring around a planet.
    flourish: bool,
    detail: usize,
}

pub(crate) fn draw(draws: &mut Draws) -> RealmChoice {
    RealmChoice {
        bg: draws.pick(BACKGROUNDS.len()),
        shape: draws.pick(SHAPES.len()),
        biome: draws.pick(BIOMES.len()),
        landmark: draws.pick(LANDMARKS),
        accent: draws.pick(ACCENTS.len()),
        flourish: draws.chance(50),
        detail: draws.pick(DETAILS),
    }
}

pub(crate) fn build(choice: RealmChoice) -> Avatar {
    let background = BACKGROUNDS[choice.bg % BACKGROUNDS.len()];
    let biome = BIOMES[choice.biome % BIOMES.len()];
    let accent = ACCENTS[choice.accent % ACCENTS.len()];
    let (body, flourish, details, landmarks) = match SHAPES[choice.shape % SHAPES.len()] {
        Shape::Island => (&ISLAND, &WATERFALL, &SKY_DETAILS, &GROUND_LANDMARKS),
        Shape::Planet => (&PLANET, &RING, &SPACE_DETAILS, &SPACE_LANDMARKS),
        Shape::Floe => (&FLOE, &WATERFALL, &SKY_DETAILS, &SEA_LANDMARKS),
    };
    let mut canvas = Canvas::new(SIDE);
    canvas.paint(body);
    if choice.flourish {
        canvas.paint(flourish);
    }
    canvas.paint(&details[choice.detail % DETAILS]);
    // Last, so the landmark stands in front of the sky detail.
    canvas.paint(&landmarks[choice.landmark % LANDMARKS]);
    canvas.finish(Kind::Realm, background, |ink| match ink {
        Ink::Body => biome.ground,
        Ink::Dark => biome.soil,
        Ink::Pupil => biome.stone,
        Ink::Frame => biome.flora,
        Ink::Field2 => biome.liquid,
        Ink::Hair => WOOD,
        Ink::White => WHITE,
        Ink::Metal => GLOW,
        Ink::Accent => accent,
    })
}