#include <execinfo.h>
#include <stddef.h>
#include <string.h>
#include <sys/errno.h>
#include <limits.h>
#include <unistd.h>
#include "assert.h"
#include "cstring.h"
#include "errors/errors.h"
#include "errors/exceptions.h"
#include "errors/report.h"
#include "object.h"

boolean stacktrace = false;

#ifdef BSDBACKTRACE
#define backtrace_symbols(FRAMES, LENGTH) \
    backtrace_symbols_fmt((FRAMES), (LENGTH), "%a <%n%D>")
#else
#define backtrace_symbols(FRAMES, LENGTH) \
    backtrace_symbols((FRAMES), (assert((LENGTH) <= INT_MAX), (int)(LENGTH)))
#endif

void reportexception(const struct exception caught, cstring const from, const int line, cstring const file)
{
    cstring systemerrormessage = errno ? strerror(errno): 0;
    cstring exceptionname = (
        caught.thrown < 0 ? (
            "invalid"
        ) : caught.thrown == 0 ? (
            "abort"
        ) : caught.thrown >= allerrors ? (
            "unknown"
        ) : (
            errorstring((error)caught.thrown).string[errorstring((error)caught.thrown).length] == '\0' ?
                (cstring)errorstring((error)caught.thrown).string : "-string-"
        )
    );
    report(
        "Debug",
        "%s; Thrown from %s() near '%s +%d'",
        exceptionname,
        caught.function,
        caught.file,
        caught.line
    );
    report(
        "Debug",
        "%s; Reported by %s() near '%s +%d'",
        exceptionname,
        from,
        file,
        line
    );
    if (systemerrormessage) {
        report(
            "Debug",
            "%s; strerror(errno): %s",
            exceptionname,
            systemerrormessage
        );
    }
    if (stacktrace) {
        cstring * const symbols = (cstring *)backtrace_symbols(
            caught.stacktrace.frames,
            caught.stacktrace.length
        );
        if (symbols == NULL) {
            report(
                "Debug",
                "%s; backtrace_symbols() failed near '" __FILE__ " +%d': %s",
                exceptionname,
                __LINE__,
                strerror(errno)
            );
        } else {
            const size_t frames = (
                sizeof caught.stacktrace.frames / sizeof *caught.stacktrace.frames
            );
            if (frames && caught.stacktrace.length >= frames - 1) {
                report(
                    "Debug",
                    "%s; Stacktrace (Warning: May have been truncated.)",
                    exceptionname
                );
            }
            for (size_t index = 0; index < caught.stacktrace.length; ++index) {
                report(
                    "Debug",
                    "%s; Stacktrace: %s",
                    exceptionname,
                    symbols[index]
                );
            }
            free(symbols);
        }
    }
    errno = 0;
}