tiny.termtex.flat

1const std = @import("std");2const alloc_arena = @import("alloc_arena");3const ast = @import("ast.zig");4const layout = @import("layout.zig");5const parse = @import("parse.zig");67pub fn renderAlloc(allocator: std.mem.Allocator, source: []const u8) ![]u8 {8    var arena = alloc_arena.Arena.init(allocator);9    defer arena.deinit();10    const expr = try parse.parse(arena.allocator(), source);11    var out: std.ArrayListUnmanaged(u8) = .empty;12    errdefer out.deinit(allocator);13    try appendFlat(allocator, arena.allocator(), &out, expr);14    return out.toOwnedSlice(allocator);15}1617fn appendFlat(18    allocator: std.mem.Allocator,19    scratch: std.mem.Allocator,20    out: *std.ArrayListUnmanaged(u8),21    expr: *const ast.Expr,22) std.mem.Allocator.Error!void {23    switch (expr.*) {24        .row => |items| for (items) |item| try appendFlat(allocator, scratch, out, item),25        .text => |value| try out.appendSlice(allocator, value),26        .operator => |value| try appendFlat(allocator, scratch, out, value.body),27        .space => |value| try appendFlatSpace(allocator, out, value),28        .fraction => |value| {29            try appendFlatGrouped(allocator, scratch, out, value.numerator);30            try out.appendSlice(allocator, "⁄");31            try appendFlatGrouped(allocator, scratch, out, value.denominator);32        },33        .sqrt => |value| {34            try out.appendSlice(allocator, "√");35            if (value.index) |index| {36                try out.append(allocator, '[');37                try appendFlat(allocator, scratch, out, index);38                try out.append(allocator, ']');39            }40            try appendFlatGrouped(allocator, scratch, out, value.body);41        },42        .scripts => |value| {43            try appendFlat(allocator, scratch, out, value.base);44            if (value.sub) |sub| try appendScript(allocator, scratch, out, sub, .sub);45            if (value.sup) |sup| try appendScript(allocator, scratch, out, sup, .sup);46        },47        .accent => |value| {48            switch (value.mark) {49                .bar => try out.appendSlice(allocator, "bar"),50                .hat => try out.appendSlice(allocator, "hat"),51                .vec => try out.appendSlice(allocator, "vec"),52                .dot => try out.appendSlice(allocator, "dot"),53                .underline => try out.appendSlice(allocator, "underline"),54                .tilde => try out.appendSlice(allocator, "tilde"),55                .check => try out.appendSlice(allocator, "check"),56                .breve => try out.appendSlice(allocator, "breve"),57                .ddot => try out.appendSlice(allocator, "ddot"),58                .acute => try out.appendSlice(allocator, "acute"),59                .grave => try out.appendSlice(allocator, "grave"),60                .ring => try out.appendSlice(allocator, "ring"),61                .overleft => try out.appendSlice(allocator, "overleftarrow"),62                .overleftright => try out.appendSlice(allocator, "overleftrightarrow"),63            }64            try appendFlatGrouped(allocator, scratch, out, value.body);65        },66        .grid => |value| try appendFlatGrid(allocator, scratch, out, value),67        .annotation => |value| try appendFlatAnnotation(allocator, scratch, out, value),68        .delimited => |value| try appendFlatDelimited(allocator, scratch, out, value),69    }70}7172fn appendFlatSpace(73    allocator: std.mem.Allocator,74    out: *std.ArrayListUnmanaged(u8),75    value: ast.Space,76) std.mem.Allocator.Error!void {77    if (out.items.len == 0) return;78    for (0..layout.spaceCells(value)) |_| try out.append(allocator, ' ');79}8081fn appendFlatDelimited(82    allocator: std.mem.Allocator,83    scratch: std.mem.Allocator,84    out: *std.ArrayListUnmanaged(u8),85    value: ast.Delimited,86) std.mem.Allocator.Error!void {87    if (flatDelimiter(value.left)) |delimiter| try out.appendSlice(allocator, delimiter);88    try appendFlat(allocator, scratch, out, value.body);89    if (flatDelimiter(value.right)) |delimiter| try out.appendSlice(allocator, delimiter);90}9192fn appendFlatAnnotation(93    allocator: std.mem.Allocator,94    scratch: std.mem.Allocator,95    out: *std.ArrayListUnmanaged(u8),96    value: ast.Annotation,97) std.mem.Allocator.Error!void {98    switch (value.kind) {99        .plain => {100            if (value.over) |over| {101                try out.appendSlice(allocator, "overset(");102                try appendFlat(allocator, scratch, out, over);103                try out.append(allocator, ',');104                try appendFlat(allocator, scratch, out, value.base);105                try out.append(allocator, ')');106            } else if (value.under) |under| {107                try out.appendSlice(allocator, "underset(");108                try appendFlat(allocator, scratch, out, under);109                try out.append(allocator, ',');110                try appendFlat(allocator, scratch, out, value.base);111                try out.append(allocator, ')');112            } else {113                try appendFlat(allocator, scratch, out, value.base);114            }115        },116        .overbrace => {117            try out.appendSlice(allocator, "overbrace");118            try appendFlatGrouped(allocator, scratch, out, value.base);119        },120        .underbrace => {121            try out.appendSlice(allocator, "underbrace");122            try appendFlatGrouped(allocator, scratch, out, value.base);123        },124        .boxed => {125            try out.append(allocator, '[');126            try appendFlat(allocator, scratch, out, value.base);127            try out.append(allocator, ']');128        },129    }130}131132fn appendFlatGrid(133    allocator: std.mem.Allocator,134    scratch: std.mem.Allocator,135    out: *std.ArrayListUnmanaged(u8),136    value: ast.Grid,137) std.mem.Allocator.Error!void {138    if (flatLeftFence(value.fence)) |fence| try out.appendSlice(allocator, fence);139    for (value.rows, 0..) |row, row_index| {140        if (row_index != 0) try out.append(allocator, ';');141        for (row.cells, 0..) |cell, cell_index| {142            if (cell_index != 0) try out.append(allocator, ',');143            try appendFlat(allocator, scratch, out, cell);144        }145    }146    if (flatRightFence(value.fence)) |fence| try out.appendSlice(allocator, fence);147}148149fn appendFlatGrouped(150    allocator: std.mem.Allocator,151    scratch: std.mem.Allocator,152    out: *std.ArrayListUnmanaged(u8),153    expr: *const ast.Expr,154) std.mem.Allocator.Error!void {155    const grouped = switch (expr.*) {156        .text => false,157        .operator => false,158        .space => false,159        .scripts => false,160        else => true,161    };162    if (grouped) try out.append(allocator, '(');163    try appendFlat(allocator, scratch, out, expr);164    if (grouped) try out.append(allocator, ')');165}166167fn flatLeftFence(fence: ast.GridFence) ?[]const u8 {168    return switch (fence) {169        .none => null,170        .paren => "(",171        .bracket => "[",172        .brace, .left_brace => "{",173        .bar => "|",174        .double_bar => "‖",175    };176}177178fn flatRightFence(fence: ast.GridFence) ?[]const u8 {179    return switch (fence) {180        .none, .left_brace => null,181        .paren => ")",182        .bracket => "]",183        .brace => "}",184        .bar => "|",185        .double_bar => "‖",186    };187}188189fn flatDelimiter(delimiter: ast.Delimiter) ?[]const u8 {190    return switch (delimiter) {191        .none => null,192        .shape => |shape| flatDelimiterShape(shape),193        .text => |value| value,194    };195}196197fn flatDelimiterShape(shape: ast.DelimiterShape) []const u8 {198    return switch (shape) {199        .left_paren => "(",200        .right_paren => ")",201        .left_bracket => "[",202        .right_bracket => "]",203        .left_brace => "{",204        .right_brace => "}",205        .bar => "|",206        .double_bar => "‖",207        .left_angle => "⟨",208        .right_angle => "⟩",209        .left_double_angle => "⟪",210        .right_double_angle => "⟫",211        .left_double_bracket => "⟦",212        .right_double_bracket => "⟧",213        .left_floor => "⌊",214        .right_floor => "⌋",215        .left_ceil => "⌈",216        .right_ceil => "⌉",217    };218}219220const ScriptMode = enum {221    sub,222    sup,223};224225fn appendScript(226    allocator: std.mem.Allocator,227    scratch: std.mem.Allocator,228    out: *std.ArrayListUnmanaged(u8),229    expr: *const ast.Expr,230    mode: ScriptMode,231) std.mem.Allocator.Error!void {232    var raw: std.ArrayListUnmanaged(u8) = .empty;233    defer raw.deinit(scratch);234    try appendFlat(scratch, scratch, &raw, expr);235    if (try appendMappedScript(allocator, out, raw.items, mode)) return;236    try out.append(allocator, switch (mode) {237        .sup => '^',238        .sub => '_',239    });240    try out.append(allocator, '(');241    try out.appendSlice(allocator, raw.items);242    try out.append(allocator, ')');243}244245fn appendMappedScript(246    allocator: std.mem.Allocator,247    out: *std.ArrayListUnmanaged(u8),248    raw: []const u8,249    mode: ScriptMode,250) std.mem.Allocator.Error!bool {251    var index: usize = 0;252    while (index < raw.len) {253        const len = std.unicode.utf8ByteSequenceLength(raw[index]) catch return false;254        const end = index + @min(len, raw.len - index);255        if (scriptGlyph(raw[index..end], mode) == null) return false;256        index = end;257    }258    index = 0;259    while (index < raw.len) {260        const len = std.unicode.utf8ByteSequenceLength(raw[index]) catch unreachable;261        const end = index + @min(len, raw.len - index);262        try out.appendSlice(allocator, scriptGlyph(raw[index..end], mode).?);263        index = end;264    }265    return true;266}267268fn scriptGlyph(value: []const u8, mode: ScriptMode) ?[]const u8 {269    return switch (mode) {270        .sup => superscriptGlyph(value),271        .sub => subscriptGlyph(value),272    };273}274275fn superscriptGlyph(value: []const u8) ?[]const u8 {276    if (std.mem.eql(u8, value, "0")) return "⁰";277    if (std.mem.eql(u8, value, "1")) return "¹";278    if (std.mem.eql(u8, value, "2")) return "²";279    if (std.mem.eql(u8, value, "3")) return "³";280    if (std.mem.eql(u8, value, "4")) return "⁴";281    if (std.mem.eql(u8, value, "5")) return "⁵";282    if (std.mem.eql(u8, value, "6")) return "⁶";283    if (std.mem.eql(u8, value, "7")) return "⁷";284    if (std.mem.eql(u8, value, "8")) return "⁸";285    if (std.mem.eql(u8, value, "9")) return "⁹";286    if (std.mem.eql(u8, value, "+")) return "⁺";287    if (std.mem.eql(u8, value, "-")) return "⁻";288    if (std.mem.eql(u8, value, "=")) return "⁼";289    if (std.mem.eql(u8, value, "(")) return "⁽";290    if (std.mem.eql(u8, value, ")")) return "⁾";291    if (std.mem.eql(u8, value, "n")) return "ⁿ";292    if (std.mem.eql(u8, value, "i")) return "ⁱ";293    return null;294}295296fn subscriptGlyph(value: []const u8) ?[]const u8 {297    if (std.mem.eql(u8, value, "0")) return "₀";298    if (std.mem.eql(u8, value, "1")) return "₁";299    if (std.mem.eql(u8, value, "2")) return "₂";300    if (std.mem.eql(u8, value, "3")) return "₃";301    if (std.mem.eql(u8, value, "4")) return "₄";302    if (std.mem.eql(u8, value, "5")) return "₅";303    if (std.mem.eql(u8, value, "6")) return "₆";304    if (std.mem.eql(u8, value, "7")) return "₇";305    if (std.mem.eql(u8, value, "8")) return "₈";306    if (std.mem.eql(u8, value, "9")) return "₉";307    if (std.mem.eql(u8, value, "+")) return "₊";308    if (std.mem.eql(u8, value, "-")) return "₋";309    if (std.mem.eql(u8, value, "=")) return "₌";310    if (std.mem.eql(u8, value, "(")) return "₍";311    if (std.mem.eql(u8, value, ")")) return "₎";312    if (std.mem.eql(u8, value, "a")) return "ₐ";313    if (std.mem.eql(u8, value, "e")) return "ₑ";314    if (std.mem.eql(u8, value, "h")) return "ₕ";315    if (std.mem.eql(u8, value, "i")) return "ᵢ";316    if (std.mem.eql(u8, value, "j")) return "ⱼ";317    if (std.mem.eql(u8, value, "k")) return "ₖ";318    if (std.mem.eql(u8, value, "l")) return "ₗ";319    if (std.mem.eql(u8, value, "m")) return "ₘ";320    if (std.mem.eql(u8, value, "n")) return "ₙ";321    if (std.mem.eql(u8, value, "o")) return "ₒ";322    if (std.mem.eql(u8, value, "p")) return "ₚ";323    if (std.mem.eql(u8, value, "r")) return "ᵣ";324    if (std.mem.eql(u8, value, "s")) return "ₛ";325    if (std.mem.eql(u8, value, "t")) return "ₜ";326    if (std.mem.eql(u8, value, "u")) return "ᵤ";327    if (std.mem.eql(u8, value, "v")) return "ᵥ";328    if (std.mem.eql(u8, value, "x")) return "ₓ";329    return null;330}

1pub const flat = @import("flat.zig");