# Generate list of LaTeX tab-completions supported by the Julia REPL
# as documented in doc/manual/unicode-input-table.rst
# The output will be rendered as a reStructuredText document to STDOUT
# Note: This script will download a file called UnicodeData.txt from the Unicode
# Consortium

include("../base/latex_symbols.jl")
include("../base/emoji_symbols.jl")

# Create list of different tab-completions for a given character
# Sometimes there is more than one way
vals = Dict()
for symbols in [latex_symbols, emoji_symbols], (k, v) in symbols
    vals[v] = push!(get!(vals, v, String[]), "\\"*k)
end

# Join with Unicode names to aid in lookup
isfile("UnicodeData.txt") || download(
    "http://www.unicode.org/Public/UCD/latest/ucd/UnicodeData.txt", "UnicodeData.txt")
unicodenames = Dict()
open("UnicodeData.txt") do unidata
    for line in readlines(unidata)
        tokens = split(line, ";")
        codepoint = parse(UInt32, "0x"tokens[1])
        name = tokens[ 2]=="" ? tokens[11] :
               tokens[11]=="" ? tokens[ 2] :
               tokens[ 2]*" / "*tokens[11]
        unicodenames[codepoint] = name
    end
end

# Render list
# Need to do this in two passes since ReST complains if the tables aren't exactly aligned
# Pass 1. Generate strings
entries = Any[("Code point(s)", "Character(s)", "Tab completion sequence(s)", "Unicode name(s)")]
maxlen = [map(length, entries[1])...]

# Prepend a non-breakable space to combining characters
# (ranges obtained from https://en.wikipedia.org/wiki/Combining_character)
function fix_combining_chars(uni)
    u = uni[1]
    isc = ('\u0300' ≤ u ≤ '\u036F') ||
          ('\u1AB0' ≤ u ≤ '\u1AFF') ||
          ('\u1DC0' ≤ u ≤ '\u1DFF') ||
          ('\u20D0' ≤ u ≤ '\u20FF') ||
          ('\uFE20' ≤ u ≤ '\uFE2F')
    return isc ? string('\u00A0', uni) : uni
end

for (chars, inputs) in sort!([x for x in vals], by=first)
    # Find all keys with this value
    entry = (
            join(map(c->"U+"*uppercase(hex(c, 5)), collect(chars)), " + "),
            fix_combining_chars(chars),
            join(inputs, ", "),
            join(map(c->get(unicodenames, UInt32(c), "(No Unicode name)"), collect(chars)), " + ")
        )

    currentlength = map(length, entry)
    for i=1:length(entry)
        maxlen[i] = max(maxlen[i], currentlength[i])
    end

    push!(entries, entry)
end

# Pass 2. Print table in ReST simple table format
function underline(str, maxlen)
    join(map(n->str^n, maxlen), " ")
end

isheader = true
println(underline("=", maxlen))
for entry in entries
    thisline = ""
    for (i, col) in enumerate(entry)
        thisline *= rpad(col, maxlen[i], " ") * " "

        # Hack round JuliaLang/julia#10825
        if i==2 && any(x->charwidth(x)==2, collect(col))
            thisline *=" "
        end
    end
    println(rstrip(thisline))

    if isheader
        println(underline("-", maxlen))
        isheader = false
    end
end
println(underline("=", maxlen))
