#include "common.h"

// -----------------------------------------------------------------------
// input functions

int
parse(io·Stream *io, int nfield, char **field, int len, char *line)
{
    int n;
    if((n=io·readln(io, len, line)) <= 0)
        return ParseEOF;

    if(n == len)
        panicf("line too long");

    if(line[n-1] != '\n')
        panicf("invalid line: expected '\n', found '%c'", line[n]);

    line[n-1] = 0;

    if(line[0] == '#' || line[0] == 0)
        return ParseSkip;

    /* tokenize line into fields */
    n = 0;
    field[n] = line;
    while(*line){
        if(*line == ';'){
            *line = 0;
            field[++n] = line+1;
        }
        line++;
    }

    if(n != nfield-1)
        panicf("expected %d number of fields, got %d: %s", nfield, n, line);

    return ParseOK;
}

int
codepoint(char *s)
{
    int c, b;

    c = 0;
    while((b=*s++)){
        c <<= 4;
        if(b >= '0' && b <= '9')
            c += b - '0';
        else if(b >= 'A' && b <= 'F')
            c += b - 'A' + 10;
        else
            panicf("bad codepoint char '%c'", b);
    }

    return c;
}

void
codepointrange(io·Stream *utf8, char *field[NumFields], int *start,  int *stop)
{
    int e, c;
    char *other[NumFields], line[1024];

    // XXX: the stop variable passes in the previous stopping character
    e = *stop;
    c = codepoint(field[Fcode]);

    if(c >= NumRunes)
        panicf("unexpected large codepoint %x", c);
    if(c <= e)
        panicf("bad code sequence: %x then %x", e, c);
    e = c;

    if(strstr(field[Fname], ", First>") != nil){
        if(!parse(utf8, arrlen(other), other, arrlen(line), line))
            panicf("range start at end of file");
        if(strstr(other[Fname], ", Last>") == nil)
            panicf("range start not followed by range end");

        e = codepoint(other[Fcode]);

        if(e <= c)
            panicf("bad code sequence: %x then %x", c, e);
        if(strcmp(field[Fcategory], other[Fcategory]) != 0)
            panicf("range with mismatched category");
    }

    *start = c;
    *stop  = e;
}

// -----------------------------------------------------------------------
// output functions

void
putsearch(void)
{
    puts(
        "#include <u.h>\n"
        "#include <libutf.h>\n"
        "\n"
        "static\n"
        "rune*\n"
        "rangesearch(rune c, rune *t, int n, int ne)\n"
        "{\n"
        "   rune *p;\n"
        "   int m;\n"
        "   while(n > 1) {\n"
        "   m = n >> 1;\n"
        "   p = t + m*ne;\n"
        "   if(c >= p[0]){\n"
        "       t = p;\n"
        "       n = n-m;\n"
        "   }else\n"
        "       n = m;\n"
        "   }\n"
        "   if(n && c >= t[0])\n"
        "       return t;\n"
        "   return 0;\n"
        "}\n"
    );

}

int
putrange(char *ident, char *prop, int force)
{
    int l, r, start;

    start = 0;
    for(l = 0; l < NumRunes;) {
        if(!prop[l]){
            l++;
            continue;
        }

        for(r = l+1; r < NumRunes; r++){
            if(!prop[r])
                break;
            prop[r] = 0;
        }

        if(force || r > l + 1){
            if(!start){
                printf("static rune %s[] = {\n", ident);
                start = 1;
            }
            prop[l] = 0;
            printf("\t0x%.4x, 0x%.4x,\n", l, r-1);
        }

        l = r;
    }

    if(start)
        printf("};\n\n");

    return start;
}

int
putpair(char *ident, char *prop)
{
    int l, r, start;

    start = 0;
    for(l=0; l+2 < NumRunes; ){
        if(!prop[l]){
            l++;
            continue;
        }

        for(r = l + 2; r < NumRunes; r += 2){
            if(!prop[r])
                break;
            prop[r] = 0;
        }

        if(r != l + 2){
            if(!start){
                printf("static rune %s[] = {\n", ident);
                start = 1;
            }
            prop[l] = 0;
            printf("\t0x%.4x, 0x%.4x,\n", l, r - 2);
        }

        l = r;
    }

    if(start)
        printf("};\n\n");
    return start;
}

int
putsingle(char *ident, char *prop)
{
    int i, start;

    start = 0;
    for(i = 0; i < NumRunes; i++) {
        if(!prop[i])
            continue;

        if(!start){
            printf("static rune %s[] = {\n", ident);
            start = 1;
        }
        prop[i] = 0;
        printf("\t0x%.4x,\n", i);
    }

    if(start)
        printf("};\n\n");

    return start;
}