// dump_json <kv|rows|manifest|csv> <file>
// Emits the parse result as JSON in the same shape as tests/mars_text/oracle/dump.py
// so the two can be compared structurally. Bytes >= 0x80 are written as
// \u00XX (one escape per byte) on both sides.
#include <cstdio>
#include <fstream>
#include <iterator>
#include <map>
#include <string>

#include "mars/text/csv.h"
#include "mars/text/flat_kv.h"
#include "mars/text/manifest.h"

using namespace mars::text;

namespace {

void json_string(std::string_view s, std::string& out) {
    out.push_back('"');
    for (unsigned char c : s) {
        switch (c) {
        case '"': out += "\\\""; break;
        case '\\': out += "\\\\"; break;
        case '\n': out += "\\n"; break;
        case '\r': out += "\\r"; break;
        case '\t': out += "\\t"; break;
        default:
            if (c < 0x20 || c >= 0x7f) {
                char buf[8];
                std::snprintf(buf, sizeof buf, "\\u%04x", c);
                out += buf;
            } else {
                out.push_back(static_cast<char>(c));
            }
        }
    }
    out.push_back('"');
}

void json_token(const Token& t, std::string& out) {
    switch (t.kind()) {
    case ValueKind::Int: out += std::to_string(*t.as_int()); break;
    case ValueKind::Float: {
        char buf[64];
        std::snprintf(buf, sizeof buf, "%.17g", *t.as_float());
        std::string s = buf;
        if (s.find_first_of(".eEn") == std::string::npos) s += ".0";  // keep it a JSON float
        out += s;
        break;
    }
    case ValueKind::Bool: out += *t.as_bool() ? "true" : "false"; break;
    case ValueKind::Bareword:
    case ValueKind::String: json_string(t.text, out); break;
    }
}

void json_tokens(const std::vector<Token>& toks, std::string& out) {
    out.push_back('[');
    for (std::size_t i = 0; i < toks.size(); ++i) {
        if (i) out.push_back(',');
        json_token(toks[i], out);
    }
    out.push_back(']');
}

// kv value: null / scalar / list, matching the reference reader's shape
void json_kv_value(const std::vector<Token>& toks, std::string& out) {
    if (toks.empty()) out += "null";
    else if (toks.size() == 1) json_token(toks[0], out);
    else json_tokens(toks, out);
}

std::string dump_kv(const FlatKV& kv) {
    std::map<std::string, const KvEntry*> last;  // exact key, last wins
    for (const KvEntry& e : kv.entries()) last[e.key] = &e;
    std::string out = "{\"values\":{";
    bool first = true;
    for (const auto& [key, e] : last) {
        if (!first) out.push_back(',');
        first = false;
        json_string(key, out);
        out.push_back(':');
        json_kv_value(e->values, out);
    }
    out += "},\"duplicates\":{";
    first = true;
    for (const auto& [key, lines] : kv.duplicates()) {
        if (!first) out.push_back(',');
        first = false;
        json_string(key, out);
        out += ":[";
        for (std::size_t i = 0; i < lines.size(); ++i) out += (i ? "," : "") + std::to_string(lines[i]);
        out.push_back(']');
    }
    out += "}}";
    return out;
}

std::string dump_rows(const Rows& rows) {
    std::string out = "{\"rows\":[";
    for (std::size_t i = 0; i < rows.size(); ++i) {
        if (i) out.push_back(',');
        json_tokens(rows[i].tokens, out);
    }
    out += "]}";
    return out;
}

const char* problem_kind(Problem::Kind k) {
    switch (k) {
    case Problem::Kind::Unrecognised: return "unrecognised";
    case Problem::Kind::DuplicateId: return "duplicate_id";
    case Problem::Kind::DeletedAndAssigned: return "deleted_and_assigned";
    case Problem::Kind::UnbalancedQuote: return "unbalanced_quote";
    case Problem::Kind::UnterminatedQuotedCell: return "unterminated_quoted_cell";
    }
    return "?";
}

std::string dump_manifest(const Result<Manifest>& r) {
    std::string out = "{\"entries\":[";
    bool first = true;
    for (const ManifestEntry& e : r.value.entries()) {
        if (!first) out.push_back(',');
        first = false;
        out += "[" + std::to_string(e.id) + ",";
        json_string(e.name, out);
        out.push_back(']');
    }
    out += "],\"deleted\":[";
    const auto& del = r.value.deleted();
    for (std::size_t i = 0; i < del.size(); ++i) out += (i ? "," : "") + std::to_string(del[i]);
    out += "],\"problems\":[";
    first = true;
    for (const Problem& p : r.problems) {
        if (!first) out.push_back(',');
        first = false;
        out += "{\"line\":" + (p.line ? std::to_string(p.line) : std::string("null")) + ",\"kind\":\"" + problem_kind(p.kind) +
               "\",\"id\":" + (p.id >= 0 ? std::to_string(p.id) : std::string("null")) + "}";
    }
    out += "]}";
    return out;
}

std::string dump_csv(const Csv& csv) {
    std::string out = "{\"header\":";
    if (csv.header) {
        out.push_back('[');
        for (std::size_t i = 0; i < csv.header->size(); ++i) {
            if (i) out.push_back(',');
            json_string((*csv.header)[i], out);
        }
        out.push_back(']');
    } else {
        out += "null";
    }
    out += ",\"rows\":[";
    for (std::size_t i = 0; i < csv.rows.size(); ++i) {
        if (i) out.push_back(',');
        out.push_back('[');
        for (std::size_t j = 0; j < csv.rows[i].cells.size(); ++j) {
            if (j) out.push_back(',');
            json_string(csv.rows[i].cells[j], out);
        }
        out.push_back(']');
    }
    out += "]}";
    return out;
}

} // namespace

int main(int argc, char** argv) {
    if (argc != 3) {
        std::fprintf(stderr, "usage: dump_json <kv|rows|manifest|csv> <file>\n");
        return 2;
    }
    std::ifstream in(argv[2], std::ios::binary);
    if (!in) {
        std::fprintf(stderr, "cannot read %s\n", argv[2]);
        return 2;
    }
    std::string text((std::istreambuf_iterator<char>(in)), std::istreambuf_iterator<char>());
    std::string kind = argv[1];
    std::string out;
    if (kind == "kv") out = dump_kv(parse_flat_kv(text).value);
    else if (kind == "rows") out = dump_rows(parse_rows(text).value);
    else if (kind == "manifest") out = dump_manifest(parse_manifest(text));
    else if (kind == "csv") out = dump_csv(parse_csv(text).value);
    else {
        std::fprintf(stderr, "unknown kind %s\n", argv[1]);
        return 2;
    }
    std::fwrite(out.data(), 1, out.size(), stdout);
    std::fputc('\n', stdout);
    return 0;
}